OB19 in SW FL
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Re: OB19 in SW FL
its a short piece to replace. With you new grinder is should not take long at all to fix. Grinders are wonderful tools When you burn through the 80 grit pad you have now, invest in a grinding pad and 24 grit disks
Re: transucer
Even at plane you will be 3-5 ' forward of the transom. However you want easy access to it so that limits you to the access between the frame before the transom and the transom about 15" on most of these boats. So drill your hole and build a dam on the inside that allows the transducer to shoot straight down with in that 15". If you only slow troll and depend ony your tranducer for slow speed trolling you can put it forward on the hull. Lowrance actually allows you to place two transducers and read from either of them.wadestep wrote:Later this week I'm going to cut the hole for the shoot-through-hull transducer. Some things I've figured out with the SEARCH button(not quite as easy as the EASY button )
1) Have to drill about a 4" hole now before glassing the outside, then plug the hole from the inside, then fill with epoxy, glass, silica, and maybe a little wood flour
2) have to put it somewhere accessable. I'm guessing that's going to be beneath the motorwell. Any tips on placement would be much appreciated. I understand not to put in centerline, due to the future skeg, and yes to put in the the hull under the motorwell for access, but any other suggestions?
should it be all the way back towards the transom, or 1-3' forward of that?
For the mix only fiberglass and epoxy, please. Silica and wood can deflect the sonar beams. I go 33% milled glass fibers to epoxy. It's a medium mix but should not have any bubbles, which are a killer, and plenty strong. Remember you have a layer of fiberglass over and under it. I also tint it blue or yellow so I can find it after the fiberglass layers are on it. For addition strength taper it toward the inside, so that the inside is smaller than the outside. That way as the water pushes up it forces the patch into a smaller area making it stronger.
Tom
Good fishing and red skys at night sailors delight
C17ccx, Mirror Dinghy
C17ccx, Mirror Dinghy
Re: OB19 in SW FL
well, it's been a while since posting, but I've made only a little progress:
I ground off the bad fiberglass splice and fixed it. It is nice and flush and has no air pockets now. I was glad to do it because it was a nagging uncertainty. It was worth doing for piece of mind if nothing else - I now sleep at night without thinking about "is that splice strong enough"
So the next step I took is drilling the holes for the transducer, raw water pickup, and drain plug.
I spent about 30 mins chopping up scrap fiberglass into small bits, and also cut out some cloth into the size of the holes. I covered the holes from the inside with ply covered with painter's plastic, and then filled the holes. I did glass cloth plug, epoxy and chopped glass mix, and another glass cloth plug. The glass cloth on top really helped it to smooth out, and the cut up fibers were enough to "thicken" the epoxy and keep it in place. This was kept just shy of flush with the hull, and I'll fair it in before applying the cloth to the hull.
The transom drain plug was actually easier. I didn't have to worry about the type of filler I used, so wood flour + glass cloth worked well, and becasue of the size of it, I used Duct tape to hold the thickened epoxy in while it was curing. Also didn't have to worry about air bubbles. I was worried about too much exotherm causing bubbles and expansion in this large of a pour, but with slow hardner I had no problems.
The next step here is to glass the seams and cloth wet-on-wet all at once. Wish me luck!
I ground off the bad fiberglass splice and fixed it. It is nice and flush and has no air pockets now. I was glad to do it because it was a nagging uncertainty. It was worth doing for piece of mind if nothing else - I now sleep at night without thinking about "is that splice strong enough"
So the next step I took is drilling the holes for the transducer, raw water pickup, and drain plug.
I spent about 30 mins chopping up scrap fiberglass into small bits, and also cut out some cloth into the size of the holes. I covered the holes from the inside with ply covered with painter's plastic, and then filled the holes. I did glass cloth plug, epoxy and chopped glass mix, and another glass cloth plug. The glass cloth on top really helped it to smooth out, and the cut up fibers were enough to "thicken" the epoxy and keep it in place. This was kept just shy of flush with the hull, and I'll fair it in before applying the cloth to the hull.
The transom drain plug was actually easier. I didn't have to worry about the type of filler I used, so wood flour + glass cloth worked well, and becasue of the size of it, I used Duct tape to hold the thickened epoxy in while it was curing. Also didn't have to worry about air bubbles. I was worried about too much exotherm causing bubbles and expansion in this large of a pour, but with slow hardner I had no problems.
The next step here is to glass the seams and cloth wet-on-wet all at once. Wish me luck!
Completed : OB19, CC14, GV10.
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Re: OB19 in SW FL
nice job. Its sooooo much easier to make those plugs at this stage.
Re: OB19 in SW FL
Yeah, Shine, it it seems like doing this later during the build would just add to difficulty. Plus, I'm really confident in their strength given they'll have continuous layer of glass covering them. I'd bet these "holes" are stronger than any of the surrounding hull.
This is another moment of overthinking, but I layed down a small piece of light glass about 30-40% larger than the holes to distribute the stiffness so as to blend in the hard spot in the hull.
I spend at least as much time overthinking as I do thinking.
wade
This is another moment of overthinking, but I layed down a small piece of light glass about 30-40% larger than the holes to distribute the stiffness so as to blend in the hard spot in the hull.
I spend at least as much time overthinking as I do thinking.
wade
Completed : OB19, CC14, GV10.
- topwater
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Re: OB19 in SW FL
Wadestep how big of a hole did you drill for the transducer
Novi 23 finally launched !
Re: OB19 in SW FL
I faired in the transducer holes, and put down a light piece of cloth to even out the "stiffness". I really didn't need to do that, as I learned during the taping/glassing.
Then Sat was the big event: taping and glassing the hull wet-on-wet.
Taping seams -
Now taped and glassed:
I also cut the 50" cloth in half, so 25x16 feet, and that finished the glassing up to the chines, with overlap.
I put 1 extra layer of tape from the bow to 2/3 of the way back along the keel - for abrasion resistance only. That is the only addition I've made to the lamination schedule. The prow has 3 layers of tape, plus 2 overlapping layers of glass cloth. It's thick and strong!!
That's good, because I am planning on adding a tow eye for high-speed towing, with lots of reinforcement from the inside as well.
The next day, while still getting a chemical bond, I used epoxy filled with 2:1 woodflour:silica by weight to "fill the weave" or as Shine put it "spread butter on the waffle". Now I'll be able to sand it for the next layer of fairing without sorrying about sanding through the glass. I'm also going to switch to Marinepoxy next for the first fairning session, then back to Quick Fair for the final job. The next 2 weeks will ensure that this is completely cured.
Now I'll be out of town for 2 weeks, so no progress for a little while.
Then Sat was the big event: taping and glassing the hull wet-on-wet.
Taping seams -
Now taped and glassed:
I also cut the 50" cloth in half, so 25x16 feet, and that finished the glassing up to the chines, with overlap.
I put 1 extra layer of tape from the bow to 2/3 of the way back along the keel - for abrasion resistance only. That is the only addition I've made to the lamination schedule. The prow has 3 layers of tape, plus 2 overlapping layers of glass cloth. It's thick and strong!!
That's good, because I am planning on adding a tow eye for high-speed towing, with lots of reinforcement from the inside as well.
The next day, while still getting a chemical bond, I used epoxy filled with 2:1 woodflour:silica by weight to "fill the weave" or as Shine put it "spread butter on the waffle". Now I'll be able to sand it for the next layer of fairing without sorrying about sanding through the glass. I'm also going to switch to Marinepoxy next for the first fairning session, then back to Quick Fair for the final job. The next 2 weeks will ensure that this is completely cured.
Now I'll be out of town for 2 weeks, so no progress for a little while.
Completed : OB19, CC14, GV10.
Re: OB19 in SW FL
I used a 4" hole saw for the transducer, and 2" for both the raw water pickup and the drain plug. I'm planning on getting a 1" ID thru-hull, so with the screws, etc... I figured I'd go a little bigger. Also got one of these in bronze:topwater wrote:Wadestep how big of a hole did you drill for the transducer
http://boatbuildercentral.com/proddetai ... d=LM_714_1
which a filled 2" hole will allow the drainplug screws to bed into only epoxy.
Completed : OB19, CC14, GV10.
- Cracker Larry
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Re: OB19 in SW FL
That looks great Wade Wet on wet is the way to go. Is your garage air conditioned?
I did the same thing with mine. Having met your wife, the structural engineer, I'd bet you're getting some outside influence in that "thinking" departmentThis is another moment of overthinking, but I layed down a small piece of light glass about 30-40% larger than the holes to distribute the stiffness so as to blend in the hard spot in the hull.
Completed GF12 X 2, GF16, OD18, FS18, GF5, GF18, CL6
"Ships are the nearest things to dreams that hands have ever made." -Robert N. Rose
Re: OB19 in SW FL
Looks great so far Wade. I agree wet on wet is the way to go. Even if you are sore and exhausted for the next few days
Very clean work.
Will
Very clean work.
Will
GV15, D4 done! Dreaming about the next one
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