Marine Plywood?

[SteveD]

Ok, got the plans for our V10. Kids and I are really excited about building the boat. <BR><BR>We went to three stores to get the plywood and are totally confused. One store (84 Lunber) had nothing but exterior grade plywood. One home depot did´nt have anything better than bcx. We went to a second Home depot that had everykind of plywood known to man. <BR><BR>What we got, not knowing the difference, was 2 sheets of 1/4" oak marine grade plywood at $19.89 per sheet, and one 3/8 " sheet of pine ACX plywood for $15.00. Will this work? <BR>They had Oak marine grade plywood, Fir marine grade plywood, but both of those only came in 1/4" or 1/2" or thicker. The Pine was the only one that had 3/8" inch. <BR><BR>We intend to Paint the boat so I´m not worried about the two different types of wood from that standpoint, but am concerned that using two different types of Plywood may screwup the engineering (boat being stronger in one place than another where it was´nt intended).<BR>Please Advise. Thanks.

[Wayne]

I have never heard of oak marine plywood. It will be heavier than fir or okume or even pine. Good exterior (no cores or few cores that are filled) is fine for a V10. The strength differences will not be a problem. Being a small v-hull, I have heard some builders talk about having some difficulty in bending the plywood. Perhaps someone else can respond to the bending characteristics of of oak plywood. I would doubt that it would be a problem. As long as that oak plywood has exterior glue (same as marine) then I would think you should have no problems.

[Skydad]

I go along with Wayne. I, too, have not heard of Oak marine plywood, but that doesn´t mean it doesn´t exist. Is it stamped marine? I think actually on the V10 that a good grade of exterior is allowed if there aren´t any voids. Maybe Jacques will chime in on this one. I bet that oak is heavy.

[SteveD]

I went and looked at the 1/4" sheets of oak and did not see any voids on the edge´s or on either side. When I look at a side I can see where it looks like planks glued together. When I look at the edge I see three distinct layers. I checked the reciept and it sure enough says 1/4 inch oak. The sticker on the board says "watergrade" which I guess does not mean marine. I´m getting nervous. I think I´ll take it back and just go with the 1/4" fir. <IMG SRC="images/forum/icons/icon_eek.gif">

[BillyV12]

Steve,<BR><BR>The only oak ply I´ve seen in Houston is interior. It also only has very thin oak veneers on the faces. The inner plies can be most any wood. If it is very thin faced, it is very easy to sand through.

[Skydad]

Steve, I think taking it back would be a wise decision. I´d be afraid of that stuff. I would bet that it is interior grade. <IMG SRC="images/forum/icons/icon_frown.gif">

[UncleRalph]

I would second the motion to take it back. A day or so ago someone posted on another board (I think it was the Bolger board on Yahoo) about some 1/4" oak plywood he bought at Lowes for $20 a sheet. It was supposed to be for exterior use, but he ran some tests and it definately was not waterproof. <BR>I see you are from Annapolis, if you want to go the expensive route, you can get marine grade Okume at Chesapeake Light Craft in Annapolis.

[jacquesmm]

Oak plywood (if it exists), will not bend.<BR>The V10 has tight curves: use Lauan exterior or Okume marine.<BR>Fir is difficult to bend but it has been done by around half of the V10 builders.<BR>Oak will be impossible to bend.<BR><BR><font size=1>[ This message was edited by: jacquesmm on 27-08-2002 20:40 ]</font>

[Mattchew]

Sorry to hear you´re having so much trouble finding decent marine plywood to use. My word of caution is to avoid the fir. I used marine grade fir plywood for my v10. Every source I asked reported that fir plywood will eventually "check", or develope fine cracks on the surface, and that the only way to prevent the checking is to glass both interior and exterior surfaces. Although I like having the extra protection the glass provides, when you consider the additional expense of glass cloth and epoxy, you could order good quality marine okume plywood. <BR><BR>Another thing I discovered is that the core of my marine fir plywood is very soft and dents easily. Even the plastic bed liner on my pickup has put dents in the wood. Not a good thing at all. No doubt, when i build my next boat I will invest in higher quality plywood.<BR><BR>And yes, the fir is difficult to bend too. I had to bathe my bottom panels in hot water to get them plyable enough to make them come together at the bow.<BR><BR>Don´t let this discourage you too much - I know how excited you are about getting started on your boat, but getting the best materials upfront will be worth it in the end.<BR><BR>Good luck and enjoy the process! <BR>Matt.

[SteveD]

Thanks Matt. I took the 1/4 inch Oak plywood back and did confirm that it was in fact Oak and that watergrade is not synonimous with "marine" grade. I had read in a number of articles that the fir would check and had opted to not use if for that reason. I decided I would use the ACX pine I think Jacques said would be fine in other posts, but went to get it and they were out. So the search continues...... I found a place here in Annapolis that sells stitch & glue boat materials but were way more expensive on everything. And for the expensive at $68.00 per sheet, I´ll keep looking for the ACX Pine.<BR><BR><font size=1>[ This message was edited by: SteveD on 27-08-2002 16:44 ]</font>