Boat Builder Central - Builder Forums

Many thanks for all the information presented by Boat Builder Central and the cadre of builders and fixers that provide so much help to those seeking it.
I have been reading here for many years, long before Cracker Larry left us. I even registered but cannot find my old registration data so just signed up again. I'm pretty certain that I never commented with the old registration anyway.

I am a young guy, approaching birthday number 70. Still working and always have some project. Lots of tools, some glass experience working on my formula race car.

In 1993 I purchased a 1983 Sea Ray 245 Cuddy Fish. The boat had been on Lake Erie from new and the owner had all the records. Basically it was taken from winter storage around June 1 and winterized and put back in the storage building sometime in September. The gentleman moved South (Charlotte, NC area) and traded the boat for a pontoon. I purchased it from the marina. My children (4) were age 5 to 15 at that point. We used the boat routinely on Lake Norman exclusively, keeping it in the marina dry storage building when not in use. Sometime around 2005 the gimbal ring (stern drive) broke which requires pulling the engine to replace. I figured I would do that myself since I am thrifty. As we were using the boat less, it languished and just stayed in storage several years. At some point I bought a trailer as I was tired of paying for storage on the boat I wasn't using. It then went to outside storage with a cover over it. A couple years back the cover deteriorated such that there was really nothing over it. I did keep the drains clear and the boat high in the front so that water did drain properly. Also, the cockpit cover was still good protecting that area and the cuddy stayed completely in the dry. Storage was cheap at $30 month. Last month new owners took over the storage and the price went up by a factor of 4 to $120, not out of line for the area, but I have 8 acres and the boat is now home. I was afraid it would be completely rotten. I have always thought that I would restore the boat and I'm getting that started.

Other than surveying and deciding what I want to do it will be next summer before I really get much done. I have a Motor home I am restoring currently and a house at the beach that needs off season attention.

However, from what I can see so far, I don't have any rot issues in the transom or stringers, which would make my restoration much easier and I could work on her before next summer. I have the boat parked on the trailer on my property. I'll have power and water at that location in a month or so and I have lots of battery powered tools.

So, I will post some pictures a bit later after I get a handle on that. I have the tutorial.

I would like to remove the stern drive and add a bracket, single engine for something in the 250-300hp range. Looks like the bracket is about 200 pounds (flotation and swim platform) and the motor another 600. If anyone knows the center of gravity location for the Mercruiser 5.7 liter that would be useful. Doing that gets rid of something I always hated, all the complexity of the stern drive and hole in the boat, plus it frees up a lot of space. Removing the transom width fish boxes and motor cover gives me right at 3 feet of additional length.

I do have two soft spots in the sole, but they seem weird in that I don't think it's related to the stringer structure. They are midway bewtween the transom and cockpit seating and to tje left and right of the gas tank. I'm guessing the gas tank cover caused water to get under the bottom side of the sole and cause some rot on the bottom of the sole but not below in the stringers. I'll show what I mean in pictures when I post those. What I will be asking for is some eyeballs on those pictures and what you experts think it might be, plus a course of action.

Thanks in advance for any help you can give me.

Barry

Do nothing until asking. Lotsa guys screw up stuff by doing it wrong.

Armstrong is the way to go on the bracket. They may even have done that boat.

CoG is basically meaningless. You only track your changes.

So, the CoG is a simple reference. Pick a point one foot ahead of the engine. Keep track of all moments in and out, or out and in, and you'll know the net effect from that point.

Getting the balance right can be tricky. I removed a Volvo 31 diesel with outdrive from a 22 foot Seasport and added a flotation bracket and a 200hp Suzuki. Also I built a 20 foot boat and put a bracket on it. Both boats ended up more tail heavy than I would have liked. Both boats need some trim tab to run close to level and that cuts down on mileage.
Try to find the balance point with the boat stock and try to match that when you add the bracket and outboard.

"Do nothing until asking."
Good advice and I will not.

"Try to find the balance point with the boat stock and try to match that when you add the bracket and outboard."
Also good advice, but I'm not real sure how I will figure out the current COG of the boat. I can't weigh the front and back like I can a race car or even an airplane. I recall that years ago when I first thought about this that there was some info I found, maybe on the Sea Ray website and I haven't visited that in years.

Alright, thanks for noticing my post, and I'm trying to figure out the pictures. I've created an album, I think. I'll try the next step and see if I can make it work.

Thanks again.

Let's see if I can get the pictures on here.

First try will just be the page from the 1983 Sea Ray brochure showing the 245CF and the smaller one:

OK, that works with a little experimentation

As she sits in my drive after some pressurized cleanup (the Bow railing is off)




The hornets nest that was under the engine cover. Rigged up a coat hanger and wire to pull the cover over after dark and then soaked the nest with hornet killer. Worked out with no stings.

The stern of the boat after I removed a bit of above deck rotten wood and the fish box that runs the width of the transom. Also removed is the sole surround of the engine. You can see a bit of the stringer on the starboard side. I see no rot below, in the stringer or transom.



The sole from the engine up to the cockpit, with the gas tank cover in place:


With the gas tank cover removed, and the red lines showing the "soft" area's, the port side being the worst:

Oops, the red lined pic has the cover in place, here is the picture sans cover:


To the left and right of the tank is what appears to be 1/2 inch plywood that forms the sides of the coffin and they are not continuous. They start at the bulkhead between the engine and gas tank area, and stop just short of the end (front) of the tank. Then they start again just past where the seat mounts are. The picture is the port side front, just under the sole. You can see the aluminium for the seat mount sticking down:

Ok, so with that initial group of pics -

The sole is solid around the engine and everywhere but the redlined area's. The softness I feel in those spots, with the port side the worst, is maybe an 1/8 inch when I jump up and down a bit. I weigh 230 pounds. I do not remember this flex being there originally. The plywood that fits under the walk around area will need to be replaced but it is solid enough to provide support for the walk around for now. The walk arounds are solid all around the boat.

That gas tank cover has no gasket. Water that went between the cover and the sole is supposed to drain to the stern end and then on out through the scupper. I am thinking that with the dirt built up in there it was not draining correctly and ran out under the sole, wetting the bottom and rotting the bottom of the sole. I'm assuming the bottom side of the sole is plywood, but I'm not sure about that. Looking down I see a pretty clean area, hard to take a picture.

Tomorrow I'll use a snake type camera to get under and take some pics. Forgot I had one of those until just now

Any thought? Assuming the problem is truly confined to these spots, just cut that area out? Cut the whole sole out and inspect/repair/replace?

Thanks!

Oh, and the gas tank really looks good, at least on top. I expect to remove it for inspection or replacement.

Cut the least amount, but all the rot.

Epoxy is your friend. It'll usually allow you to lay in cleats under the existing sole to patch to...

"Cut the least amount, but all the rot."

OK, gotcha. That was what I was hoping to hear. I'll do further inspection with the camera underneath and also further inspection of the stringers and transom. It all looks good and seems solid. I can't tell about the very bottom of the transom interior as the stern drive is in the way. Outside looks good. Since the gimbal ring is broken it's hard to use the drive to put stress on the transom, but what little I can do it seems solid. I have to pull the engine and drive anyway so it will get thoroughly inspected when I do that.

Thanks very much!

Once the gear is out, use an awl to probe around the transom and drain plugs out and such. Soft wood is rotten. Wet wood may be okay.

Yea, I've used a pick and found no problem with what I can get to inside, and I'll do the same when I get the sterndrive out of the way. I'm going to have to build a temporary a frame to get the motor out, so it's going to be a while. I have material on hand at least.

I got some pics from under the sole with my camera on a stalk. Not the best pics or good focus but good enough I think.

First picture is under the sole. It is just glass, no plywood. I think the boat is constructed from 3 molded parts; the hull, common to all 245 based boats in the lineup, then the sole, specific to the boat, and then the upper structure. I'm guessing the lay the molded sole in on the glued up cleats and that's it.

Since the soft spots are between the support along the tank (which feels solid) and the sides, and there is nothing between, I tried to take pics of the cleats along the hull. I have two, not the best as it's hard to hold the camera still on a stalk 2 foot out and manage the phone to take the pic at the same time. It looks to me as thought the cleat is the rotting part. In the pictures the hull is green area towards the bottom of the pic. See what you think:

OK, one more pic adding to my guess that the rot is on the top, under the sole. Between the engine bay and the gas tank bay there is a bulkhead. Not a very heavy bulkhead at maybe 1/2 inch, but it's there. At the stern end of the tank, port side there is a hole near the top which could only come from some crumbly/rotted wood. I don't see any black rot but the whole is visible. It is not soft under this spot however. Just looking at it, I think it could just be reinforced once the tank is out of the way, without pulling the sole up here. Or, I could just carefully cut the sole from here forward, check and repair the cleats and bulkhead, then put the original sole back in place. EDIT: I'm assuming I could cut the sole around the outside at the hull and get it off the good cleats without destroying it. That may not be a good assumption. Most of the cuts wouldn't even be seen. Opinions welcome.

Hard to tell until you get it apart some..

OK, understood. I'm not going to do any cutting until I get the engine out and take out the gas tank. Maybe that will provide better answers.
I might even consider going back with the stern drive and just use the boat like it was originally designed. We'll just wait until I can see what I am working with. It looks a lot better that what I was expecting, so far anyway

Thanks

My experience has been opening up the boat is a lot like opening Pandora's box. You are not going to know what you are working with until you get her opened up. For me I feel getting rid of the I/O and going bracket/outboard is a huge upgrade but it is not going to be cheap.

"...but it is not going to be cheap."

This is true. But going used/rebuilt on the engine makes it reasonable IMO. The darn bracket cost seems rather high, until I price the aluminum and figure the time it would take me to tig weld it (I can, and I have a tig welder, but I'm slow). Even at $3.5k to 5k it's not really worth my time.

I have considered just fixing what I have. The outdrive is probably OK, just the gimbal ring is broke and I already have one I bought years ago. The engine has been sitting and has the original manifolds, etc. It has to be rebuilt, which I can do, but the time is another issue. I just have too much to do as I get older I've looked at the price of rebuilt and new long blocks, manifolds, etc., so it remains a possibility.

In any event, if the structure on the bottom is good, and for now it seems as if it is, and if the transom isn't rotted, then the cost of the mechanical parts and the other stuff I will need to restore the boat is far cheaper than the equivalent from what I can see. In any event, the boat has a lot of meaning for me which makes some of the economic consideration moot. At the same time, I'm not going to sink 25K in a boat worth maybe 5k if in decent running condition. Whatever I spend on an engine is recoverable to some degree, so I'm not going to count that too highly.

I'll do some more investigation. I need to rig up my camera so I can get a clearer picture and also "see" to the bottom better. I'm still learning how to manipulate that thing.

At the moment I'm just happy that it's not a total rotten boat. Maybe it is and I've yet to discover it, but so far it's been a pleasant surprise from what I expected.

Thanks for looking!

Just to show how bad a boat can look and how it cleans up, a few pics. The first two are when it came home, before I pressure washed her with water only. The last picture is of a small section I test finished this morning. Using a porter cable DA polisher I first used Meguiars # 49 oxidation remover, a medium compound. Then Meguiars #45, a polishing compound. After that I applied some flagship wax. The wax I applied by hand as my backing pad crumbled. You can see the reflection of the motor home I'm restoring in the hull now. I did about 2x3 section. It will get done again when I do the whole boat. Now that I know for certain that I will save her, I'll invest some time and effort into getting her cleaned.

I'll get started building a gantry to pull the engine this week. It will be useful removing the tank as well.

I decided to go ahead and dismantle the port side cockpit walk around support. It need to be removed to access the floor if I decide to cut into that area, and there was rotten plywood at the beginning of the walk around.

The port side also has a built in tackle box which I would eliminate anyway. I never did like it as it partially blocked the cuddy entry.
First picture is as delivered by Sea Ray + 39 years
Then a pic with the tackle box out. The tackle box actually has supports built in that go under the walkway, since the plywood side panel ends at the box.

Last pic is with everything removed. Pretty easy to replace everything except the plywood has to be 1/2 and the local place here only carries 3/4 okoume. It takes one sheet to do both sides. Shipping 1 sheet would be ridiculous. Maybe I use a sheet of birch of something else, sealed with epoxy, then either painted or covered with fabric/vinyl. I never did like the plywood look there anyway.

The starboard side is the same, the plywood just goes to the cabin as the tackle box is not there.
I'll probably screw some temporary supports to be able to walk on the walk around while I'm waiting to do other work.

looks like a big project but the clean up was impressive. Will be nice when completed.

Thanks wp.

IF the transom is good and if the stringers are good, then the job will not be too bad. I really expected those parts to have some issues, and until I get the engine out and the drive mounting off I will not know for sure. I'm expecting to find some imperfection down at the bottom, but I'm hoping it is minor enough to just get repaired.

Tomorrow, well today now since it's 1am, I am building a structure to hold a tarp over the boat to keep it dry. And maybe I'll get the snake camera out and mounted to something for better inside pictures.

I managed to get better pictures from under the sole today. It appears that the cleats along the hull side were made from plywood and not coated for water protection. First pic is just the camera on my phone showing a clear picture of the side, sole and cleat. The next two with my snake camera, held steady for a better picture. Seems pretty clear there is rot present on the cleat, unless the glue they used is just black

So, it seems clear I have to do some cutting. Pictured is where I'm thinking but I need some opinion here. The stern area to the left and right of the engine is solid, but that is a short area width wise, might be rot in the cleats back there. The front is solid also, so I'm thinking of cutting across in front of the bulkhead where the gas tank starts. Picture is of the sole and the areas I propose to cut are shown in red. Or, I could try to remove the whole sole.

Should I try to save the sole and put it back down? Or just build a new one with plywood, glass, and epoxy? (edit) It dawns on me to ask, since the sole seems to be a chopper gun construct and the same for the gas tank cover, it is pretty heavy. Would there be a substantial weight savings using the ply and fiberglass cloth? ( I know the weight of the current sole is unknown)

Also, if you can imagine the sole and the white gelcoat sides are a single molded piece. Is there any reason that I should not try to cut along the sides where the cleats are? Cut through the glass and cleat at the same time? It will be somewhat difficult under the walk around which is the majority of the cutting. If I don't try to save the sole it doesn't matter and I can just cut it out a piece at a time. Would and oscillating cutter work? Or does it require a rotary cutting blade? I have tools. And if there is something better I'll buy it.

I see no foam for flotation. Second pic is of the area to the port side of the gas tank where the 1/2 ply is to hold up the sole there. It's very flat and I'm guessing the hull has a top and under that top there is foam. Just guessing, what do you think? (you can see the tank in the pic)

Thanks in advance for any advice!

Also, the width of the sole toward the stern is approximately 80 inches wide, and from the front proposed cut is about 130 inches to the stern. 3 sheets of plywood would cover this area, 4 - 5 if I do the whole sole replacement.

What thickness of plywood and what glass layup do you suggest? I have discovered I can get Okoume 1/2 and 3/4 locally (don't know what the quality is however) which avoids shipping cost. Glass and epoxy I'll order form Boat Builder Central. I have to put in an order for epoxy and glass anyway for the motor home restoration I'm doing, so I can just add it to that.

I'd first try to see what thickness was there first but if it's 1/2" or less from factory then it's up to you really. I personally am a fan of the 'go big or go home' motto but that's not always good, for vertical pieces it's less necessary but if that's where everyone will be standing and there's only 3 stringers or something then thicker should be better (assuming you glass both sides, etc.

Thanks WP.

I'm mainly thinking about weight and weight distribution. Best I can tell the Mercruiser has a horizontal COG of just about the back of the engine when the stern drive is accounted for. Weight is something around 900 pounds. I'll replace that with a bracket and outboard that will probably come in around 700 pounds, so I'll lose a couple hundred, but shift 700 roughly 2-3 foot back. I should be able to move my batteries pretty far forward since I now know there is plenty of room and height under the sole for them. The gas tank is about as far forward as possible now unless I change the front bulkhead location. All this is going to require the sole to come up anyway. The sole would be supported in 4 places if I hold to the current design, one on each side of the gas tank and then each side. The worst case span wise is about 30 inches.

So, just wondering if I can shed some weight with a new floor, which is impossible to know unless I know the weight of the existing. I can get that when it's removed. I can use 1/2 or 3/4 plus the glass and epoxy. I just don't know what is enough...

Have a water hose and a fire ex close by and then cut the deck with a 4 inch grinder and a thin cut off wheel. I have cut a lot of glass recently and not had any problems doing it this way. If that scares you use a skill saw with a carbide blade. The multi tools are great but there are better choices for this job.
For your deck I would order 7 foot sheets of NidaCore from BBC. One or one and a half inch thick. I do not think the cost will be any greater and you will get a stiffer deck. Thicker=stiffer.

I think you are correct Fuzz, and I appreciate the guidance. This afternoon I decided to get the seat pedestal/mounts out of the way, and I knew the port side seat mount would have a big hole so that I could see precisely how the sole was made. I'm not sure what made me think there was no plywood in the construction, probably the gas tank cover, but that was wrong.

Pictures, first showing the area I remove the seat mounts and the 2nd showing a close up of the sole construction. It measures 1.25 inches thick, 3/4 plywood and glass a quarter inch thick on each side.

I understand the stiffness increasing as we increase the distance between the glass. I'll have to get off the old first, and at this point I'll plan to remove it all, and then I can see what will work best. I did not realize the price of the Nida core was competitive (or better) than plywood so that's what I'll plan to do. What would you suggest for the glass layup on each side?

I assume that you glass one side of each sheet, then butt blocks below plus the cleats, and then glass the top after it's in the boat?

Thanks greatly!

I forgot to add, there was no sealant of any kind present on the seat mounting plate holes. The port side, which is a removable seat, was the worst since the hole was cut and no sealant around the cutout. From the day it left the factory every time the sole got wet there would have been water soaking into the plywood in those spots. There are a few other screws that have no sealant, like the ones that hold metal angles screwed to the soles to attach the walkaroud supports on the bottom along the sides. I'm guessing that is why the rot has occurred.

Plywood sourced locally is okay. Any composite core might require edgework. Plywood decored and recored is the ideal, but most are too lazy to recore or even epoxy seal edges.

Anything requires at least one layer of 1208 in epoxy to prevent ingress.

I'd go 1/2" plywood or 18mm core or 25mm honeycome with veil... the nice thing about ply is it doesn't require inserts for screws, but this is where guys get lazy and done decore and record with thickened epoxy..

You have the right idea about how to lay your deck down. As far as what amount of glass to use that depends on a couple of things. What bracing will there be, how far apart, what thickness is the core, what resin will be used? The gillnet boats up to 45 foot around here are using 1.5 core with two layers of 1708 each side. This is done with poly resin. Those are work boats and might have 10,000 lbs stacked on them at times. You will not need to be that heavy I am just showing what works for them.

Fallguy, Fuzz, thanks for the reply's.

I have to check my gas tank clearance to determine the thickness of the sole that I can go with and clear the tank. It's raining today or I would have done that already. I'm thinking 1.5 plus glass is doable, maybe a single layer on the bottom and two on top. I could also probably raise the sole a small amount if need be. Since the original is 1.25 total I would think even 1 inch nida core and glass would work. But I would prefer to go thicker if there is room.

Thinking ahead to the balance of the boat, if I have it correct, the Mercruiser Sterndrive engine/transmission weight is perhaps a shade under 1000 pounds with almost 700 of that engine weight (heavy manifolds). Assuming the engine horizontal COG is near the center of the engine, just back of the envelope calculations and rough measurements place the total COG at the rear of the engine, maybe 10 inches forward of the transom. With the bracket weight and an outboard of 250hp, I'm coming up with a total weight of approximately 700 pounds. That 700 will have a horizontal COG that is roughly 30 inches further aft of the original. I have two batteries, about 120 pounds, located at the rear next to the engine, that I should be able to move forward, at least 120 inches, probably more. the battery move has 4 times the effect of the engine move (120 / 30), so in effect I offset the COG engine move by a counter move of 480 pounds (4 x 120 pounds). While I know dimensions are not yet exact and the actual COG currently might be off, it would seem to be fairly easy to re-balance the boat, especially since I shave nearly 300 pounds on the powerplant and possibly more in the sole replacement.

Any error in my thinking that you can see?

Thanks!

The easiest way to redo a sole is to keep a 2" wide section of old sole around the outside and set the new on top.

I'll keep this reply short for conversation.

So, in that case, it's going to be higher by the thickness of the new sole, right?

In your COG calculation don't forget to take off the weight of the stern drive that was hanging off the stern before you took it off. 200lbs by whatever length helps you. Remember the COG of the boat is measured from the helm or slightly behind it on most boats. Good luck on your project. Tom

Thanks Tom. The 1000 pounds is the total, engine and stern drive, and just measuring where they are located I came up with a rough guess that the combo had the cog of that assembly at the rear of the engine, about 10 inches forward of the transom. So, I'm confusing the issue referencing COG, but what I meant was the COG of what I take out and put back in, figuring if I can end up close to where I started I'll be OK. I hope that makes sense...

fallguy1000 wrote: ↑Thu Aug 04, 2022 8:21 pm Do nothing until asking. Lotsa guys screw up stuff by doing it wrong.

Armstrong is the way to go on the bracket. They may even have done that boat.

CoG is basically meaningless. You only track your changes.

So, the CoG is a simple reference. Pick a point one foot ahead of the engine. Keep track of all moments in and out, or out and in, and you'll know the net effect from that point.

Re-reading your advice here. And that is what I'm attempting to do, just keep up with how I change it. I just picked the back of the engine since I *think* that is the COG of the sterndrive assembly.

Barry_CF wrote: ↑Tue Aug 16, 2022 8:38 pm So, in that case, it's going to be higher by the thickness of the new sole, right?

Yup

fallguy1000 wrote: ↑Tue Aug 16, 2022 10:04 pm

Barry_CF wrote: ↑Tue Aug 16, 2022 8:38 pm So, in that case, it's going to be higher by the thickness of the new sole, right?

Yup

Seemed clear, but just in case
Thanks!

This afternoon I started working on the outside of the transom, removing the swim platform, the cylinder for the trim tabs (I'll get the tabs off tomorrow), and the stern drive. With the drive out I can start disconnecting the engine to get it out. I still have to build my gantry but that should only take a few hours I hope.

Every screw I removed, and there are quite a few, came out cleanly, no water poured out nor did any rotten wood show up. Since I put all the screws back in I would torque them down and they all screwed in tightly. So, I'm hoping the evidence is the transom is good, at least it's better than what I could have found. I should get the final verdict when I get the engine out and the stern drive transom components out.

If all the screws were above the water line you might have got really lucky

Fuzz wrote: ↑Sat Aug 20, 2022 2:46 am If all the screws were above the water line you might have got really lucky

Some were below, there are two screws on each side of the outdrive that held the lower swim platform supports. They were submerged when in the water and came out clean, dry, and torqued back down. I'm going to keep believing until I can't

I finished removing parts on the transom, took off the trim tabs and removed the outer part of the scuppers. Still looking good. I had one screw in one trim tab that didn't get tight when I put it back in, but it didn't even try, so I think it was probably over tightened and stripped when installed.

I got the motor ready to pull with the exception of the throttle cable I think. Pretty easy actually. All the nuts seem to come loose pretty well. I had given them all a squirt or two of PB blaster prior to today. I probably missed something... The motor mount bolts are all easy to get to.

I designed my gantry for the motor removal this evening. It can do dual duty as I need something to hold a tarp over the front of the motor home I'm restoring. After I get the engine out I can use it there.

Once I get the engine out I'll do a better inspection on the transom and stringers. The stringers sure appear solid. I stood on them while I worked on the motor disconnections. Could be a problem at the transom if the transom is a problem. After I get the engine out I'll probably pressure wash the inside. It's not that bad but certainly could use a bit of cleanup.

Picture of the engine with the removable surround taken off. This is before I started disconnecting stuff. Th e battery's are sitting on top of the port side stringer. You can see the starboard side with paint missing due to getting blasted with the pressure washer earlier. There is no give standing on those. Of course the wood inside could be rotted and hidden by the glass work I guess. After I get the engine out and do a cursory inspection I'll ask for some specific instructions on how to check this stuff out. The transom hole should tell that story I'm guessing. Should I drill test holes in the stringers? And if so, how?

First, after getting engine out, visual inspection.

Then use an awl, by hand and see if the awl penetrates deep into any wood at any openings.

Then, if your hearing is good, take a plastic mallet or flip a decent sized screwdriver over and start banging on the stuff with a consistent swing, not too hard, and listen for a unique, hollow sound or rattle. If you hear variation, drill a test hole like 3/8" and then use the awl again or the drill and see if the wood is wet or mush.

Thanks Fallguy. I have done some tapping on the outside of the transom and it sounds good to me, solid sounding. But I'm not sure what I'm listening for to be honest. I get a sharp report that changes slightly as I get to what I know is a change due to construction, like at the bottom where the hull joins the transom or the side where the side and transom join together. I have done some poking with an awl but glass covers most everything and I have refrained from trying to poke to hard into the glass.

So far the only wood rot seems to all be topside on panels that were never protected (all removed now) and the plywood in the sole. On a couple bulkheads (maybe that's what they are, they are 1/2" thickness which seems thin) at the very top there is some crumbly wood, but as you go down it gets hard again. I think this supports my theory that the holes in the sole that were not sealed allowed water to slowly soak the plywood in the sole. Also, the gas tank cover was meant to drain freely down the length and eventually out the scuppers, but if that area gets contaminated it would run under the sole and towards the aft end, and then hit the top of the bulkheads.

So, just so I'm clear, if I have a suspicion or want to test, use a drill bit, say 1/4 and drill into an area and check the wood that comes out. Clean and dry is good. Black and or wet is bad. Then fill the hole with an epoxy glue. Is this how you guys would do it?

3/8" hole

Drill 1/2" in

Feel the shavings for moisture

Push the awl into the hole in 3/4 directions. Any penetration is fail. Not like 1/8", I mean real rot.

Repair immediately with epoxy putty.

Epoxy putty I use is 2.1-1 fumed silica to epoxy

Or your own with wood flour, I don't know that ratio.

I you have a small set of hole saws I like to use that to check the wood. The plug from the hole saw lets you get a real good look at what you have. I use wood flour/epoxy to fill the hole. You can butter up the plug good and put it back in the hole.

Fuzz wrote: ↑Sun Aug 21, 2022 11:06 pm I you have a small set of hole saws I like to use that to check the wood. The plug from the hole saw lets you get a real good look at what you have. I use wood flour/epoxy to fill the hole. You can butter up the plug good and put it back in the hole.

I like it as long as you don't do it on the transom!

Fuzz wrote: ↑Sun Aug 21, 2022 11:06 pm I you have a small set of hole saws I like to use that to check the wood. The plug from the hole saw lets you get a real good look at what you have. I use wood flour/epoxy to fill the hole. You can butter up the plug good and put it back in the hole.

So, for the stinger go all the way through? I'm not sure how wide the stringers are at this point. Everything is covered with a deck that exists under the sole. At least, I'm calling it a deck. It's pretty flat except where the gas tank sits. On top of that are the 1/2 sole supports that run alongside the gas tank, with the same running the boat width behind and in front of the tank.

I *think* Sea Ray built the hull and covered it with a deck*, then added the sole/liner supports. Then the liner went in that includes the sole, and finally the upper structure. That's how it appears to me anyway. Once I cut the existing sole out maybe I can see more, but it appears that there is a wide stringer on each side of the gas tank. Maybe there is something under the tank, or in front of the tank.

*I also am assuming there is foam under there since none is present under the sole.

Anyway, thinks greatly for taking the time to respond. Once I get the motor out and that area cleaned up I'll get some pictures and maybe that will help.
Fallguy, thanks for the guidance on the drill.

I should have explained it a little better. Start the cut with the pilot bit inserted. If doing the transom or some other place you do not want to cut through then remove the bit. Drill half way or so through and use a chisel to knock the plug lose. This way you get a real good look at what you have. I like this better than using a drill since all you have to look at is shavings. But shavings works too and is a little quicker.

Fuzz, thanks for the clarification. I thought about that, but I have never tried to knock a partially drilled hole saw plug loose before. I have plenty of hole saws and that would seem to be better than the drill bit only.

Either method, if it's really rotten it would be like drilling into a pile of wet toilet paper. It will go deep faster than hard wood.

Yeah, typically, an awl will punch polyester with rotten wood, no drill required.

OrangeQuest wrote: ↑Mon Aug 22, 2022 1:34 pm Either method, if it's really rotten it would be like drilling into a pile of wet toilet paper. It will go deep faster than hard wood.

Well, the transom is rotted. Some how my "testing" missed the area that is clearly an issue. As I got everything disconnected from the engine and did some cleanup to get stuff out of the way, I pushed on an area and discovered a clear issue. The first picture shows the area circled in red. It's pretty bad. As you get closer to the stern drive transom mounting it gets hard again, and the other side is fine.

Also noted is the yellow area. This transom is not completely flat. That yellow is an offset, bumps to the outside. I have a picture showing that bump on the outside as well. Also, notice that in the red area it gets thinner there, the transom is thicker by at least half an inch where the drive fastens.

So, the question is, does anyone know what that is? And how will I fabricate a new transom with that offset? For the transom area below the upper offset I'll clearly just make one thickness side to side, probably about 3 inches for a bracket and 300hp engine.

A 3rd pic shows the starboard side with two holes circled in green. There is one hole just like it on the port side. You can push into the hole and dig stuff out, rotted wood maybe, it wasn't real clear. I'll inspect further tomorrow. For now I'm guessing Sea Ray drilled those holes to fill the area with flotation foam. I bought the boat from the marina as a trade form the original owner, so I don't think they are any sort of inspection hole.

The port side seems to be the worst, which is the side the transom rot is real bad on. I don't know how I missed it earlier... The motor mounts lag into some blocks set to the inside. The port side lag bolts practically pulled out while the starboard side were firmly anchored.

So, we know the transom is toast, which I was originally expecting. Once I get the engine out I'll get the sole out and see what the stringers look like. As long as they are repairable within reason I'll fix it.

Do not cut into the transom from the outside.

Get the engine out and go from there.

Don't worry about the offset for now either.

I am sorry you found rot but I am not surprised. There is both good news and bad here. The bad is it all has to come out. The good news is the more rotten it is the easier the work will be. No matter what you are going to need to cut the stringers back 12-18 inches or more. This will allow you to have room to tab the transom in right and will give a good look at the stringers. When you get to the bump out part I do not think it will be a problem. That can be dealt with a little later on. For now work on getting every thing removed that can come out.

Dan and I cross posted but we are both thinking the same way

You may have to lift the cap for this repair, but let's have a look at things with the engine out. Lifting the cap sucks, but can be done. You have to put some spanners in so the boat doesn't shape shift and the cap won't go back down, so keeping it on is best, but sometimes, impossoble to work around.

fyi

Alright, I appreciate the help.

I am familiar with the basic transom and replacement guidelines, having read here for years. I do know I'll be cutting the glass off on the inside and removing all the transom plywood. And I know that I have to cut the stringers back as well and that will then expose what I have for structure.

Honestly, this is what I was expecting on a 40 year old boat that has been neglected the last 10 years or so. I let myself get fooled by appearances

Anyway, it will be a better boat than when it left the factory. I'm not really disappointed. I just have to keep in mind the value to some degree.

Thanks again!

fallguy1000 wrote: ↑Mon Aug 22, 2022 9:26 pm You may have to lift the cap for this repair, but let's have a look at things with the engine out. Lifting the cap sucks, but can be done. You have to put some spanners in so the boat doesn't shape shift and the cap won't go back down, so keeping it on is best, but sometimes, impossoble to work around.

fyi

I think lifting the cap on this one with the cuddy might be more difficult than most. I've considered that. It appears the liner is screwed in place all around the sides and at the transom. Then the cap is put in place. I suspect it is very heavy with the cuddy. I can cut the cap like I see typically done to gain access to the transom and the stringers. Since the sole has to be replaced anyway it will be pretty open.

I'll listen very closely to what you guys say as I'm a complete novice at this stuff.

If you only take out about 3 foot of the deck until you get the transom done that will help keep things in shape. And you will have a level spot to set things on and that is a huge help. Speaking of keeping things in shape make sure you have the boat well supported before cutting lots of stuff out.

Fuzz, good point. I'll do it like that, Only cut 3 foot of the deck and get the transom in place before going further.

I have the boat on the trailer, which has bunks, and a support up front for the bottom of the hull. I have to pull the trailer forward to get the motor out, but after that it can remain in place until I finish. I've been reading what I can to remind me how this is done. I *think* a bunk style trailer is pretty good, correct?

A good fitting bunk trailer might do the trick. I think I would go ahead and support the hull at the outside transom edges.

Fuzz wrote: ↑Tue Aug 23, 2022 1:32 pm A good fitting bunk trailer might do the trick. I think I would go ahead and support the hull at the outside transom edges.

Will do, Thanks!

OK, progress is slow the last several days. I did get started building a gantry to pull the motor. The height is 12 ft as I will need to lift the motor 6ft from the bottom, then pull the boat out from under, and drop the motor on a sled I have not built yet. Picture is one side. I have the beam built up, a pair of 2x10's with 1/2 ply in between, all glued and screwed together. So, just another side to build and the the beam racking supports. I hope to get the motor out this weekend.

Next picture is my proposed cut lines for the cap at the transom and initial floor cutting. Eventually the whole sole gets cut out and replaced, but per the earlier suggestion I'll leave it until the transom is complete. So, on the cap, how far from the transom should I cut? How much room to tab and work do I need? You'll notice the teak will cover the cut on the topside and I'll add bolsters that will cover it on the inside, so very little of the repair will show when I'm done. Assuming the stringers are good (I know they will not be), how much do I cut those? Knowing that I will have to cut out any and all rot. But, how much to get the transom done first?

Last, whats the best guess on the epoxy and filler I need to order from BBC? I'm planning on 3 inches of plywood, so 4 sheets of 3/4. Transom width at the top is about 92 inches wide and the depth to the bottom is about 46, so nearly full sheets will be used. I don't see any point on scrimping here as I'll hang a bracket off of it with a 300hp motor. How many layers of which fiberglass product? And how much and what kind of tape to purchase? I will not make the order until I check out the stringers so that I can make a guess on material for those. I also have some epoxy and glass needs for the motor home I'm restoring so I'd like to order it all at once. Anyway I'll get the motor out before I order.

Thanks in advance as I'm probably not going to get back online until late tomorrow evening.

I would cut the cap on the stern at the transistions.

Too tired to comment more.

Cut lines look good. Maybe cut the sides on the transitions as Dan said. When you get that cut and out of the way you will need to cu the stringers back and that will be a huge tell on what they are like.

Cut on purple I'd say, not red unless you have a problem with the purple being too little.

Inside the transistions. Easier to fix. Lots.

Fallguy, do you mean inside the corner and over the side? Or inside the corner and over the back? It's probably clear to anyone else

I appreciate the help. For the glass inside, I'm assuming using the biax 12 or 17 ounce without the mat. Which one and how many layers would you suggest? Need to see what's there first?

Thanks again!

Edit: Looking at the tutorial pics It seems the cut goes over the top and back, not the side. So I think I found the answer.

Nothing on the side on top if you can cut the insides; they are easier to repair. So, up the corner and over the back at the inside corner of the transistion.

Disregard extra lines.

Gonna have to put a stretcher across the hull. Probably give yourself ? 5'.

FG, thanks for the clarification. I agree that would be easier to repair. If it gives me room to work it should be fine.

By stretcher and 5', you mean a board (or something) stretching from port to starboard side on top of the cap to hold it all in alignment? And the 5' is the distance from the transom forward for the location or an amount that gives me enough room to work?

Room to work is all. Yes, something to keep things from canting..

If you can't fit the ply in this way; you just cut more relief in the back is all.

Thanks FG, I understand.
I'm hoping to get the motor out this weekend. If I can get the other gantry side built tomorrow I should be able to manage it.

Everything seems to slow down sometimes. I finally got the gantry built only to find I could not get the 10 foot wide beam up there to complete the bracing. I had an idea in the back of my mind that might be trouble...

Anyway, solution is pulleys mounted near the top and I'll lift the beam up so that I can then just lift it up and over into the saddle for it. Then I can add the braces and I'll be ready to pull the motor. Maybe this is the weekend We'll see.

Picture showing the two gantry sides sitting on each side of the boat, ready for the beam to get lifted in place. Maybe tomorrow. I have to work on my truck so we'll see if I get to it.

The gantry is up. Despite my planning, it was a pain in the rear. The beam is heavy and at the limits of my reach. I used the pulleys to get it near the top And then lifted it into position. Once in place I finished drilling for the bolts and added the bracing.

It's not bad, I could lift the motor as it sits I believe. But I'm not entirely happy with the lateral stability. Those long 4x4's have a bit more flex in them than I anticipated. So, I will add some bracing about 3/4 up to the ground to steady it up. Fore and aft it's pretty solid.

Maybe I get that motor out this week. Seems like a lot of work just to get the motor out, but I now have a reusable outdoor gantry for anything else I may have, like mounting an outboard eventually.

The rope you see across the top is just my temporary line to hold a tarp up.

Almost... Got the chain host hung and motor connected, lifted as a test and it looked good. Set it back down while I get everything else ready. Motor home had to be moved, battery dead, and not able to bring it back, so I discovered the price increase for batteries. Geez.

Trailer is hooked up to move the boat from under once I lift the motor up. It's going to be anti-climatic I think. The gantry seems more than capable. I plan to get the motor out tomorrow if some business thing doesn't pop up.

Motor is out, easy peasy once everything was ready.
I need to dismantle my gantry and drag the motor to it's storage spot, and get the boat back into it's home position. I'll get the rest of the assembly off the transom, check to see how bad the rot is*, clean up the whole thing and then it will be time to add additional support for the next step.

*I know the transom is toast and there is some stringer rot, just don't know how far the stinger problem goes. If I had to guess, the port side stringer is the bad one and the starboard side appears to be fine. Until I start cutting back I won't know the answers of course. Anyway, the stringer rot stops somewhere between the stern and the bow

Barry, please read the Plywood Transom Replacement artical by the Bateau Tech support team, I forgot to mention it is just above here the 3rd post down. It will walk you through replacing your transom. Tom

Good job! Now you can get a better look at things.

Fuzz wrote: ↑Thu Sep 22, 2022 2:35 pm Good job! Now you can get a better look at things.

I don't see a picture of a better look yet!

Anyway, the stringer rot stops somewhere between the stern and the bow

That is for sure! Let's hope closer to the stern than the bow. We may need a bigger shovel.

Tom, thanks, I've read it several times along with some of the threads on transom replacement. Good information for sure.

Orange, never fear, there will be pictures, eventually. I'm hoping to get the remaining parts off the transom and cleaned up this weekend.

Fuzz, thanks for the encouragement and we'll know more soon enough

Taking the gantry apart/getting the beam down was about as difficult as putting it up. I try to make things so that I can work on my own, even though my sons are close by and are happy to help. I think in the future I will mount the beam on the ground and then get help to stand the gantry up. All the holes are drilled for the braces so it should be doable now.

One remarkable thing, the hoses all look pretty good. They are at least 30 years old, perhaps 40. I removed one just to see how it looked inside and how pliable it was. I'd have guessed it was 3-4 years old, tops. I'd replace them all anyway if I were reusing the engine, but I'm stunned by how good they look.

I got to the transom stripping this afternoon. Hard to see those two bolts on the bottom of the exhaust Y I could feel them, and pictures taken showed they were there, but for whatever reason getting the socket on them was elusive. Eventually I wore it down however and off it came.

The rest was pretty straight forward. I still need to figure out how to remove the power steering from the transom plate.

As I already knew, the transom is toast. Bad enough that perhaps the stripping of the plywood will be easier, although the upper sections may not be so bad. Picture here with a screwdriver inserted about 1 inch into the ply...

So, now the pics from inside. The first pic shows the area that is thinner than the area the stern drive mounted to. It is outlined in red. The transom at the cutout is 2 inches thick and appears to be 2 sheets of 3/4 ply and 1/4 thick glass on the outside and inside. In that thin area I would guess they used only one sheet of 3/4 ply. Looking at how the stringers tie in I'm guessing Sea Ray engineered it to save plywood with adequate strength.

The width of the 2 inch thick part is 24 inches and the height of the transom from the very bottom to the top where the plywood appears to end (underlined in yellow) is 32 inches. Above the thin parts on each side is the same thickness as the center, 2 inches.

The 2nd pic shows where I propose to make the initial cut across the bottom to cut back from the transom and get a view of the stringer structure. I chose a position just short of the motor mount pads which is approximately 18-19 inches from the transom. Obviously if the stringers are rotted further than this I'll have to cut more eventually. Does this look light the right plan? Cut here, remove all the transom rot, restore the transom, then move on to the stringers and finally the sole.

If you need more pictures to advise just let me know. I appreciate all the help.

Also, in the picture, just inside what I assume will be the first stringers (from center), is a 3/4 strip of plywood that sticks up. You can see it has significant deterioration. It is just painted and has no structural purpose I can see except one, there were painted 2x4's that were mounted vertically to support the sole surround that has been removed.

Almost forgot, my plan at the moment is to use 4 sheets of 3/4 ply for the transom, which would result in a 3.5 inch total thickness with 1/4 glass inside and out. Alternatives are 3 sheets resulting 2.75 inch total thickness, or 2 sheets of 3/4, and 2 sheets of 1/2, resulting in 3 inch total thickness.

I will laminate the sheets together outside the boat.

I'm not seeing a downside to the thicker transom at 3.5, other than a small added expense, but maybe I've not thought of something. Anyone see a problem with that?

That rotted plywood was stringers of sorts. Crappy stringers but still stringers. I would go ahead with your plan and get things removed and cleaned up. 3.5 inch transom would be really thick not sure you need that much but there is time to think it over. Also if things are not totally straight 2-3.5 inches of plywood is not going to conform to the transom skin. I like putting in one layer at a time for that reason.

Barry_CF wrote: ↑Sun Sep 25, 2022 10:41 pm Almost forgot, my plan at the moment is to use 4 sheets of 3/4 ply for the transom, which would result in a 3.5 inch total thickness with 1/4 glass inside and out. Alternatives are 3 sheets resulting 2.75 inch total thickness, or 2 sheets of 3/4, and 2 sheets of 1/2, resulting in 3 inch total thickness.

I will laminate the sheets together outside the boat.

I'm not seeing a downside to the thicker transom at 3.5, other than a small added expense, but maybe I've not thought of something. Anyone see a problem with that?

Laminating all the ply outside is pretty hard..it is going to get to be too heavy to manipulate for the bond. It will be full of voids on the edges. Start off by buttering the existing skin with a 1/8" vee trowel, precoating the ply, then buttering it with a 1/16" vee trowel and pressing the thicker butter into the hull with pins and light bolt pressures. Edge squeezeout indicates good pressure; something you'd not see with a 3" lump.

Understood on the placing one sheet at a time. I considered the weight but hadn't considered how difficult the bonding would be at that weight. And good point on being able to see the squeeze out, makes sense.

When doing a sheet at a time, do you add the putty between the ply edges and the boat every sheet in order to make it easy to get it full without voids?

After posting I thought about that, trying to get putty all under 3+ inches of narrow space, probably impossible to do correctly.

So, I'll get it all cleaned up, cut the bottom back, and go from there. That might be a while as I'll be on the coast for a few weeks in Oct and then working a project in November. Maybe I get some of it done this week.

Thanks again for the help.

Yup. Add putty to the edges for each panel.

You can prefit all the panels. That way you can place say four pins on the corners and then spot the thru bolts for clamp pressures.

Also, make sure to precoat all the surfaces with mixed epoxy. It is ideal to do the precoats about an hour before the vee trowel work. It takes a surprising amount of epoxy to do well..

It might be wise to to the first two panels one day and then follow with a 2nd day for the next 2. ...precoating the sides to get buttered each day. But if you got enough mustard you could try all four. The problem is the first layer will be gelling before you finish, so, the pins would need to come through the back and the clamp pressure would be late.

FG, understood. I'll get all the panels ready and probably do it over two days, 2 panels at a time. I'm going to have to plan on the clamping bolts. It would be nice if I settled on a bracket and had it first since that will require holes for the through bolts. I plan to make larger holes when done and fill with epoxy, but I could start with bolt sized holes first and use them as clamps. I should probably plan it that way. Thanks!

Barry the first thing I would do is fill the hole from the stern drive. I would sand down all the edges around it so that when you tape it in the tape, and it was even with the rest of the transom. Tom

TomW1 wrote: ↑Tue Sep 27, 2022 12:15 am Barry the first thing I would do is fill the hole from the stern drive. I would sand down all the edges around it so that when you tape it in the tape, and it was even with the rest of the transom. Tom

Tom, I was thinking it would get filled after the new plywood was in place, but I had not really thought about it that much. I don't understand what you mean. Should I place something on the inside (after prep) before the plywood goes in to patch the hole against (something that the epoxy will not stick to), then start the plywood process?

Since the outside glass is about a quarter inch thick, I thought I would cut patches to fit the hole and laminate those in place and then cover the outside with another layer or two, then fair it all in. But I was thinking you did that after the plywood was in place. Since the hole repair is below the bracket it will not look too bad. I guess I'll have to read up on that, it's good that you point it out, thanks.

On further thought, should I cut a 1/4 inch thick piece of ply to fit the hole and epoxy it in place after the plywood is in place, then cover with cloth and fair in?

Is the transom dead straight side to side? If not when you try to pull the plywood up tight to the glass skin you will most likely pull the skin out of shape. 3/4 ply will be stiffer than 1/4 inch of glass. If it is not straight think about laying in a couple sheets of 1/4 plywood first. One layer at a time and let it go off.
If you fill the hole first make sure to grind a taper and do not let the inside glass end up higher than the skin.

Barry_CF wrote: ↑Tue Sep 27, 2022 12:39 am
Tom, I was thinking it would get filled after the new plywood was in place, but I had not really thought about it that much. I don't understand what you mean. Should I place something on the inside (after prep) before the plywood goes in to patch the hole against (something that the epoxy will not stick to), then start the plywood process?

Since the outside glass is about a quarter inch thick, I thought I would cut patches to fit the hole and laminate those in place and then cover the outside with another layer or two, then fair it all in. But I was thinking you did that after the plywood was in place. Since the hole repair is below the bracket it will not look too bad. I guess I'll have to read up on that, it's good that you point it out, thanks.

On further thought, should I cut a 1/4 inch thick piece of ply to fit the hole and epoxy it in place after the plywood is in place, then cover with cloth and fair in?

I would think this would be correct. Cutting a filler plug and glue it is after the transom plywood is up. Not sure if Fallguy or Fuzz seen this figured I would mention it again to see what they say.

Well, I would not bother with the keyhole until after.

For the concerns about the first skin distorting; the way to deal with this is to use a 1/8" vee trowel on each side and end up with a thicker glue seam, but it is a lot, so each job may vary. A clean and flat and good surface, maybe 1/8 on existing skin and then 1/16" on ply. I would also neat coat the skin and ply an hour before thixo. The harder bit is making sure the mud is thick enough so the hilltops of the vees do not sag. Fumed silica gets added and mixed in the pail. After mixing it and you feel it is about as stiff as possible, you lay it all flat on a board to prevent it from kicking off. Epoxy is rated in 100 gram masses. If you mix a ball of 12 oz of epoxy and silica; it is about 4 times thicker than the rating and will kick in 30 minutes. All my thickened mixes go on cardboard and get laid flat with a 3-6" flat hand trowel.

The keyhole glass should be taper repaired after the ply is in with a 12:1 ratio or 3" minimum, barring any odd thickness. So, say it is 1/4" thick. 12*1/4" is 3". That is about 4 layers of 1708 plus gelcoat or fairing. You will be sanding the entire transom for gc or paint, so stay low enough for fairing compound. This is done in reverse of typical lamination with the smallest piece laid in first. If you are worried about entraining air on the edges; you can apply 1/16" vee of epoxy on the taper. The repair can also be done with only csm. The way this is done is by taking a piece of plastic and laying it on the spot and sharpie marking the hole bottom. Cut the plastic out and then transfer the shape to the csm. Then add an inch to each of the next pieces. Csm is best torn and not cut using this method.

Anyhow, this would be my approach to the keyhole and concerns about distortion of the skin. The skin may distort slighly under clamp pressures, but this can also be faired and gives you a good guide to stopping the pressure.

By the way, in all my face lamination work, 12oz is my go to amount. I like mixing in a 1/2 gallon container. More epoxy becomes harder to homogenize and the extra time spent seems not worth it to me.

Ok, I'm getting what you've said and appreciate the guidance.
The transom is pretty straight. I think there may be a bit of bow that is due to the weakness from the rot. I checked it somewhat when I was gathering data for the bracket. I think it is supposed to be straight/flat. The upper part does have a bow to it, but I'm guessing it has no ply up there, above the step I pointed out in the picture. I'll check it again. If it's not straight enough then perhaps I'll use a 1/2 thick sheet (that is the thinnest I can get locally) for the first lamination with a bit of extra epoxy for insurance.

So, fill the hole after, which makes sense to me. I will plan on 1708 for that and fairing after. I've done some of that kind of work in the past, but with lighter stuff. I understand the progressively larger glass pieces here.

12 oz. I've never mixed that much before. But I'll give it a try, probably sneak up on it

"The harder bit is making sure the mud is thick enough so the hilltops of the vees do not sag. Fumed silica gets added and mixed in the pail. After mixing it and you feel it is about as stiff as possible, you lay it all flat on a board to prevent it from kicking off."

Got it. I'm sure I'll need some experience. I do have some work to do on the motor home that will involve epoxy, foam, and ply, so I'll try some of these principles on that to learn.

Rough estimates on epoxy usage...

Neat coating surfaces..

Use a 4" adhesive or mohair roller 1/8-3/16" thick. Adhesive rollers are sold in 9", I bandsaw them to 3". 2 oz for the roller and losses and 2 oz per sq yd of each surface

Thixotropic mixture...I've forgotten the numbers a bit..but let's say the mixed volume of resins is 3 times as much.

A vee trowel of 1/8" covers average of 1/16". A square yard of surface is thus 36x36x0.065" or 85 cubic inches. 1.73 cubic inches of volume per liquid ounce or 5.19 cubic inches per ounce epoxy using 3x. Let's round to 5 to make is easy. 85/5 is 17 ounces epoxy for a yard of troweled material. From memory; this is close. Then a 1/16" trowel would be about 8.5 or say 9 ounces epoxy.

For the first bond, if rough, you'd need 17 oz times 1.5 with 1/8 trowel on boat and 1/16 trowel on panel. All subsequent bonds are troweled at 1/16, but each side of each board, so the rate is 1. I am close-ish from memory.

Point is, it takes a surprising amount of epoxy. Make sure to precoat and butter both sides. After the first bond; you'll be tempted to use only the 1/8" on one side; don't.. The chance for it to end up with lumps and air
Gaps is greater I've found. You know this after tap testing or other ways.

It doesn't really matter the direction of the vees, but even coverage is important; no skimping.

FG, thanks very much. I've copied that for quick reference.

It helps a lot to have some experienced guidance, cuts the learning curve down. I've done some epoxy work with lighter glass and carbon, but I've never done anything quite like this.

Thanks again!