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Me and a buddy are getting ready to build two GF16’s. We’d rather just head up to Lowe’s and pick up plywood rather than have it shipped. What’s a recommendation for plywood from them? Don’t want to break the bank but don’t want junk either. Thanks in advance for advise!

RickFenn

Neither of the Lowes by me sells much that is worth using. The only thing most guys will suggest is good exterior (not pressure treated) ply as a last resort, but the best you'll find there is usually BCX. It's ok for some decks, and bulkheads, but not much else, and it's much heavier.
You will end up paying more to get it right then the good ply would cost you to begin with. If you want to save on shipping try to source good ply locally, but lowes doesn't really carry any.

There is a reason you buy Marine Plywood....

25 years ago, you could find good exterior abx and bcx, not true today.

I built a Chalmette 14 (another designer), used Lowes and HD best ext ply, 80 % finished it started coming apart... Pulled it out front and put a sign on it "free fire wood"! As they say "pay now or pay later....

This is from BBC's site:

Welcome to our Marine Plywood Online store!

Why marine plywood?

Small boats:

While small stitch and glue boats can be successfully built with inexpensive exterior plywood, there are many advantages to using quality marine plywood.
•Marine plywood provides greater protection: A small scratch through the resin or glass, if not repaired immediately, may expose the plywood to water. Exterior plywood may not last long in that case.
•Marine plywood increases the resale value of your boat.
•Marine plywood is stronger and has consistent mechanical properties, with no voids.
•Marine plywood is easier to work with, especially when bending, and finishing.
•For small boats, quality 4 mm plywood is a good substitute for the ¼ inch exterior ply often specified.
•Marine plywood (except for Fir) will not check. That feature may by itself pay for the difference in cost. To get a good finish with Douglas Fir or Pine, the hull will require extra fiber glassing and large amounts of fairing compound. This is not necessary with Meranti or Okoume.

Larger boats:

The use of marine plywood is a must for larger boats.
Fast planning boats are subjected to serious bottom pressure and quality marine plywood should be used for the hull panels if only for mechanical reasons. The designer of your planning power boat probably specified marine grade plywood for that reason.
Large displacement type boats that spend all their time in the water, at the dock or at sea, should also use quality marine plywood. While the fiberglass and resin will protect plywood, any scratch or dent may allow moisture to creep in and damage cheaper plywood. Marine plywood will give you peace of mind in addition to all the advantages listed above.

Big box stores aren't going to have good ply in stock. Try calling around to lumber yards and see what they have or what they can get.
I should have taken my own advice and called around since there was a lumber yard that happened to have marine ply in stock. Instead I ordered it through Menards and had to wait 3 weeks for it to arrive. Shipping charge wasn't too bad. It was ship to store for around 13-15 bucks if I remember correctly and then I drove over and picked it up.

Besides I don't think I've seen 1/4" exterior ply in stock at any of the big box stores. Biggest I've seen is 4x4 panels.

I did find locally in DeLand Florida, American made Marine Fir plywood. I used one sheet as a sole (floor) in the FS14 SandPiper. It was covered with epoxy and a vinyl marine flooring. Never again, very thin veneers and just ugly looking ply!

Capt UB wrote: ↑Wed Feb 13, 2019 2:32 pm I did find locally in DeLand Florida, American made Marine Fir plywood. I used one sheet as a sole (floor) in the FS14 SandPiper. It was covered with epoxy and a vinyl marine flooring. Never again, very thin veneers and just ugly looking ply!

the marine ply I ordered through menards wasn't bad at all. Just took a long time for shipping.

RickFenn, take a little time and search out your local lumber yards to see if you can locate true marine plywood. If you are not successful, call me' as buying enough marine plywood for two GF16's will cost the same as shipping for one. Don't use Lowe's or HD, just poor quality and you will be disappointed in a short amount of time. Again, if you can't find good marine plywood, call us and we will price it out for you including Terminal shipping which is the most reasonable venue!! Jeff

Rick do like Jeff said. But while you are at it order all the building supplies needed and have them ship it to you guys all at once. I would highly recommend getting more epoxy than what it called for in the build notes, like double the amount or more. Narfi and I had BBC ship a good size order to us here in Alaska and it worked out very well cost wise. If they can make it work to us then shipping to you is no problem.

Fuzz wrote: ↑Wed Feb 13, 2019 3:06 pm Rick do like Jeff said. But while you are at it order all the building supplies needed and have them ship it to you guys all at once. I would highly recommend getting more epoxy than what it called for in the build notes, like double the amount or more. Narfi and I had BBC ship a good size order to us here in Alaska and it worked out very well cost wise. If they can make it work to us then shipping to you is no problem.

Good point! I've already gone through 2.5 gallons of epoxy and had to order 2 more. I just hope it's enough.....

piperdown wrote: ↑Wed Feb 13, 2019 1:09 pmBesides I don't think I've seen 1/4" exterior ply in stock at any of the big box stores. Biggest I've seen is 4x4 panels.

My HD has full sized 1/4" BCX that I'm using for the deck template of my MF14. Note I said "template". It's not actually going to be part of the boat.

I'm using cut offs from the template and the 3/4" BCX used to make the work table as shims and cleats while I assemble the MF14's framework. As I cut it up I'm discovering voids and delaminations all over the place. The BCX does a good job of laying flat and not causing any trouble if you screw it down. But it would cause all kinds of entertainment if you tried to put a bend in it, as one does building a boat.

The HD by me I noticed they had some very thin (3 or 4 mm?), very cheap 4' X 8' sheets that would work for making templates. I did a quick web search and found a Mom and Pop lumber yard a few miles from my work warehouse. They have a very good selection of marine ply that they have had a number of years so I would call it seasoned marine ply. But I was pleased with their price, very pleased. Will be getting my last few sheets soon.

Welcome to the group Rickfenn, Some good advice so far, and I'm in complete agreement with the others on not using junk ply. Since you'll be purchasing materials for 2 boats the shipping from BBC will be minimal, especially worthwhile if you can buy all, or at least the majority of your supplies on one order. If you can afford to buy the Meranti ply, while not as light weight as the Okoume, will still be an excellent quality marine ply guaranteed to never give you any future trouble, and also nice to work with. For the 2 boats, and being budget sensitive, I suggest using the Marine Epoxy brand, it's quite excellent. You won't have the benefit of using the corresponding System 3 products like Quick Fair, but you'll save a lot of money making your own fillers. My suggestion for the two boats is; One 4 1/2 gallon, and one 6 gallon kit of epoxy, Minimum 5 pounds wood flour, very cheap, so I'd order 10 to be sure, 6 pounds Micro Balloons, 4 pounds Glass Bubbles, 1 pound Silica, 1 pound non skid, if you plan on this type of deck finish, 1 pound Graphite powder, if you plan on using on the hull bottom, A few notched spreaders that work great for spreading and even film thickness of fairing compound, that you can trowel flat with a wide spreader, A metal fiberglass roller, graduated mixing cups, at least 1 gallon of primer, and paint if you know what color, and what brand you'll be using. 2 boxes of 100 extra large orange rubber gloves, the best gloves you'll find anywhere. They also sell some essential hardware, rub rails etc., so don't be shy, order away, and start building. Hope this helps. Good luck, Mike

seaslug wrote: ↑Wed Feb 13, 2019 8:38 pm You won't have the benefit of using the corresponding System 3 products like Quick Fair, but you'll save a lot of money making your own fillers.

Mike, forgive my ignorance, but I thought if you let the marinepoxy fairing coat cure fully, that you could use Quick Fair as the final coat? I was planning on using the marinepoxy and BBC fairing filler for the first couple of coats and then use Quick Fair for the (hopefully) last coat.

That's correct, as long as you give the epoxy time to cure fully you can switch brands, but I was just trying to help them out saving some money by using the less expensive epoxy and mixing fairing fillers and filleting mix, which would offset some of the shipping cost so they could buy quality plywood from BBC.

seaslug wrote: ↑Wed Feb 13, 2019 10:14 pm That's correct, as long as you give the epoxy time to cure fully you can switch brands, but I was just trying to help them out saving some money by using the less expensive epoxy and mixing fairing fillers and filleting mix, which would offset some of the shipping cost so they could buy quality plywood from BBC.

Whew! Glad to know!

Marine plywood is stronger and has consistent mechanical properties, with no voids.
Marine plywood is easier to work with, especially when bending, and finishing.

wrote: Marine plywood is stronger and has consistent mechanical properties, with no voids.
Marine plywood is easier to work with, especially when bending, and finishing.

and lighter. and epoxy grabs it more consistently.

I've built several little boats, mostly on the cheap, so I can speak to this from experience.

One I used 4mm Okume marine, one AC exterior, one Lauan/ mahogany/ meranti (not sure which they look close- not marine rated but passed a boil test), one BC exterior, and 3 cheap Canoes with 1/4" underlayment.


The exterior plywoods use a LOT more epoxy and take a lot more fairing. With pine plywood you need to finish all surfaces with light cloth rather than just sealing with resin, or the grain seems to "pop" loose in areas, breaking down the epoxy barrier. It's likely that you will spend in cloth and resin about what you save on plywood. And the boats are heavier. My son's 8' long AC plywood kayak weighs WAY more (nearly double) than my daughter's 12' lauan/meranti/mahogany boat- they are built the same width from a scaled down CC14 plan. In this case, it wasn't a huge deal- he's super light and I needed a little weight to get the chines in the water, but on a big boat it would be a big difference. It's also splintery to work with and doesn't bend real consistently (only 3 plies so stiffer one way than the other) or easily (it's real stiff and harder to pull bow seams together).

One of the 3 underlayment canoes has serious delamination in the plywood. These were taped seams, graphite bottoms, and wood sealed with 2-3 coats of epoxy plus paint. I haven't seen the other 2 for a couple years so I don't know what they look like. I sure wouldn't use that again. It's also rather fragile- doesn't take impact well and has some internal gaps that broke when bending, we had to recut those pieces.

The meranti/lauan/mahogany and the Okume was a whole different story. The plies are thinner and more numerous, it bends great. No internal gaps/ voids in the marine stuff. It's light. The surface finish is super smooth and easy to fair. And the panels I got were dead flat, not all bowed or warped like exterior.


I second the opinion above- have Jeff quote shipping it all with yor epoxy and cloth. Even the 6566 Meranti will be a HUGE improvement over exterior plywood, and when you net out the amount of epoxy and cloth you save, plus time, plus frustration in getting the lines fair, plus surface fairing and sanding, it's worth the extra $. I say this as a cheap guy who has put myself through way too much work to save a buck here and there. Also I really enjoyed the "good" plywood builds more than the cheap plywood builds, and I ended up with better boats.


Whatever you choose, build on!

Just to keep the record straight, Lowe’s actually does sell 11/16” and 7/16” fir marine ply, not that I would necessarily advocate it’s use.
They call it 3/4” and 1/2” but it’s a little thinner.
If it came down to not being able to build a gf16 due to a tight budget, use the fir and buy the glass and epoxy here.
Otherwise, do the better option and use all top quality materials.
I probably spend more money on consumables when I build a boat than on the ply that I always buy right here from this site.

Aripeka Angler wrote: ↑Thu Feb 14, 2019 7:34 pm Just to keep the record straight, Lowe’s actually does sell 11/16” and 7/16” fir marine ply, not that I would necessarily advocate it’s use.
They call it 3/4” and 1/2” but it’s a little thinner.
If it came down to not being able to build a gf16 due to a tight budget, use the fir and buy the glass and epoxy here.
Otherwise, do the better option and use all top quality materials.
I probably spend more money on consumables when I build a boat than on the ply that I always buy right here from this site.

Maybe Lowe's does in FL but it's not available in KS or MO, at least not online. It shows up in the search but says not available for in store pickup or delivery. Maybe it can be ordered at the pro-desk but I'm not sure.

No Lowes around here in Lakeland has marine ply. Think it's a very local thing in some areas.

silentneko wrote: ↑Fri Feb 15, 2019 10:22 am No Lowes around here in Lakeland has marine ply.

https://www.lowes.com/pd/3-4-CAT-PS1-09 ... 8/50254845

Fir marine ply is not hard to find, even if your local Lowe’s doesn’t stock it.
Like I said earlier, I wouldn’t use fir unless I was on a tight budget...

I recently saw some of the best looking fir 1/4” ACX that I have seen in years at a home depot here in Anchorage. Was tempted to get some just because, but factoring in cost of resin and glass plus the effort involved, it just doesn’t make a lot of sense to build a boat with it anymore.

Hi RickFenn,
You should listen to all above comments before You buy the plywood, I definitely agree it is worth to buy the best marine ply you can get and as you both need 14 sheets of plywood shipping cannot be the stumbling block. Your boats will last a lot longer with marine Okoume plywood.
Please let us know what you have decided.
Greetings from Karl

Jeff ships plywood at a very low cost...

Please be ware of buying so called Marine plywood from the big box stores. I have seen the quality go down significantly over the last 10 years. Unless your using it for a short term boat project that will not last more than 5 years or so buy the good ply here and have it shipped to you or find local sources of Meranti/Okume. Don't use CDX except for small test boats, but build on, build on, build on.

Tom

There is no "best" ply from any box store. I used some ply from Home Depot to make a console. It was made in Chile, don't remember the brand name. Anyway, I used a lot of this ply for house projects and scraps left outside never delaminated. It seemed like a good idea. It soaked up more epoxy than I've ever seen wood soak up. The expansion and contraction cracked the epoxy and soon failed. Turned out to be a bad idea.

Break the boat project down into its main parts. Hull, fiberglass and epoxy, engine, paint and fittings. The hull is the foundation on which all else is based. Don't hold me to these numbers, they are for example only. You will spend roughly $300 on box store good ply. The CNC kit here is $1400 and $650 for bulk goods. $7-800 fiberglass and epoxy. $2-3000 engine and systems (used), $3-400 paint and fittings. Another $1000 in things I can't think of. Now factor in all your time and effort. Lets say it cost $6500 to put the boat in the water. By going with cheap ply, you saved $1100 over the kit price and $300 over bulk sheets. The cheap ply will surely take way more epoxy than you planned (more cost), will need to be fully glassed (more cost and weight) for any hope of protection and weigh far more than Okoume. And it will fail in 5 years, tops.

You wasted all of your time and effort, which is the most valuable part of the project. You wasted epoxy, fiberglass, and paint. You should still have your engine and salvage fittings. Is it still worth it to save a few hundred dollars?

Looking at it from a different angle, using lesser plywood is skimping on something you can’t fix later on. If you skimp on the motor with a cheap, worn out unit, you can fix that later when more money becomes available.

Plywood for a boat floor is categorized by grade, and marine plywood is either A or B grade. The outer part is A grade, while the opposite side is B grade. The core can be a B grade or much better. It’s usually made with 7-ply lamination that is bound by waterproof glue. The thickness would be.75" or thicker because of this finishing.

Just a FYI this thread is years old. And 0.75" for just a boat floor on a small craft is insanely heavy. Even on a larger craft I would use maybe 1/2" at most. 3/8" is enough in most cases if properly done and braced.

I would also use a 4 or 6 oz ply fiberglass on both sides to prevent checking. Tom