what type and finish plywood is this? pics inside

[weider1717]

Curious if this exterior plywood in the pic looks to be bcx or cdx? Also is it pine or what?

is it marine plywood?

wanting to replace it with the same type finish and grade etc. and whatever type wood as in pine or whatever it is.

thanks

 

[kaferhaus]

Re: what type and finish plywood is this? pics inside

That is CDX plywood. It could have been made from any of several species of softwood. Usually some variety of fir or pine.

CDX is usually made from the least expensive wood that's closest to the mill producing it.

Some guys here will squawk but I think it's fine if you fill the surface voids and use some thinned epoxy to seal it well before using it.

It's also usually full of moisture off the shelf and requires a good deal of drying time while stacked properly before you can expect the epoxy to get good penetration. Most guys store it inside for a month or more before using it. And beware if you lay it flat on the floor it will never dry out... put some "stickers" (long skinny flat strips of wood) between it and the floor and between each sheet so that air can circulate under the wood. I would re-stack mine every week while shuffling the sheets.

 

[sschefer]

Re: what type and finish plywood is this? pics inside

That is CDX plywood. It could have been made from any of several species of softwood. Usually some variety of fir or pine.

CDX is usually made from the least expensive wood that's closest to the mill producing it.

Some guys here will squawk but I think it's fine if you fill the surface voids and use some thinned epoxy to seal it well before using it.

It's also usually full of moisture off the shelf and requires a good deal of drying time while stacked properly before you can expect the epoxy to get good penetration. Most guys store it inside for a month or more before using it. And beware if you lay it flat on the floor it will never dry out... put some "stickers" (long skinny flat strips of wood) between it and the floor and between each sheet so that air can circulate under the wood. I would re-stack mine every week while shuffling the sheets.

100% correct.

 

[Bondo]

Re: what type and finish plywood is this? pics inside

Ayuh,...

How many times are you going to ask this Same Question,..??..??

You started 2 threads about this Same question the other day,+ after they were combined by the Mod.s, it's danm near Unreadable....
Have you posted this Same Question elsewhere in the forums today,.?. Again,..??

 

[weider1717]

Re: what type and finish plywood is this? pics inside

Ayuh,...

How many times are you going to ask this Same Question,..??..??

You started 2 threads about this Same question the other day,+ after they were combined by the Mod.s, it's danm near Unreadable....
Have you posted this Same Question elsewhere in the forums today,.?. Again,..??

Because I can't get a consistant answer.

 

[weider1717]

Re: what type and finish plywood is this? pics inside

That is CDX plywood. It could have been made from any of several species of softwood. Usually some variety of fir or pine.

CDX is usually made from the least expensive wood that's closest to the mill producing it.

Some guys here will squawk but I think it's fine if you fill the surface voids and use some thinned epoxy to seal it well before using it.

It's also usually full of moisture off the shelf and requires a good deal of drying time while stacked properly before you can expect the epoxy to get good penetration. Most guys store it inside for a month or more before using it. And beware if you lay it flat on the floor it will never dry out... put some "stickers" (long skinny flat strips of wood) between it and the floor and between each sheet so that air can circulate under the wood. I would re-stack mine every week while shuffling the sheets.

You're fairly sure that it's not BCX plywood it sounds like...I wasn't sure. I've heard both but you're the 1st that sounds like that know for sure and fact what you're talking about.

is BCX a fair amount nicer looking wood than this? How can you be sure it's not BCX? Just curious, because I would like to know how to tell the difference.

Reason I have been thinking it's BCX is because online pictures of CDX are FULL of small to med size knots.

this board has some be spread out not packed full with them.

 

[Bondo]

Re: what type and finish plywood is this? pics inside

Because I can't get a consistant answer.

Ayuh,... That's because they're Opinions about a Picture....

 

[Utahboatnut]

Re: what type and finish plywood is this? pics inside

Not saying I'm a wood expert but do have 20 yrs experience as a carpenter for whatever its worth. Judging by the photo it does look like cdx with some type of sealer on it. One thing to keep in mind is that ANY lumber today is not what it was even ten years ago. If the knots are bothersome to you go through as many sheets as needed until you find one that is somewhat clear. Or go with the BCX or pay for the ACX, I don't think a higher grade would be warranted in that application but its up to you. Those outside plies are probably doug fir which is all speed grown now thus the increased number of knots. You may find whatever you use to seal with might raise the grain anyway, thats why I would suggest the CDX that you pick through to find a decent sheet. Good luck hope I'm not repeating what you already know...

 

[weider1717]

Re: what type and finish plywood is this? pics inside

thanks for the replies! but now I'm really confused which it is..I pulled the carpet off and on the side the carpet was on I atleast can't SEE any knots.

and look at the finish I can see what looks like fiberglass strands....and a hard finish on it what kind of finish is this? but the other side looks like just spar varnish on it.

here are some pics of the carpet side with the carpet off.

does this side not look of better quality? maybe it might be BCX.. this side being B quality and the other side with the knots the C quality side? or no?

 

[Utahboatnut]

Re: what type and finish plywood is this? pics inside

I agree the carpeted side looks to be much better finish quality, probably to avoid depressions in the carpet due to knots. It looks like they just put one layer of mat on that side to strenghen/waterproof the top(carpet) side and then just thinned or straight resin on the under side and edges to seal/waterproof the rest of it. One layer of mat flat like that doesn't add a ton more strength but you could do the same if you wanted when you re-build. Is the piece soft? it looks to be in pretty good shape just wondering why your re-building it? I think you will have better luck finding ACX readily avalable over the BCX, but might be different in your area. Its up to you but if you use epoxy resin instead of poly that project is not going to be cheap...

 

[weider1717]

Re: what type and finish plywood is this? pics inside

I agree the carpeted side looks to be much better finish quality, probably to avoid depressions in the carpet due to knots. It looks like they just put one layer of mat on that side to strenghen/waterproof the top(carpet) side and then just thinned or straight resin on the under side and edges to seal/waterproof the rest of it. One layer of mat flat like that doesn't add a ton more strength but you could do the same if you wanted when you re-build. Is the piece soft? it looks to be in pretty good shape just wondering why your re-building it? I think you will have better luck finding ACX readily avalable over the BCX, but might be different in your area. Its up to you but if you use epoxy resin instead of poly that project is not going to be cheap...

good reply, thanks

ok to start with after seeing both sides is it cdx, bcx or acx?

2nd what do you mean by "mat" and where do you buy it? something i can do myself?

and the finish is that epoxt resin of the "mat" or poly resin or what?

and yes on the under side some spots are a bit soft and the 5 ply layers are coming apart in some areas I just want to replace this middle pull out board only the rest of the floor is rock solid. I wouldn't think it would cost too much to redo this section the way this one was done with a new piece of plywood.

thanks man

 

[RyanSS]

Re: what type and finish plywood is this? pics inside

who cares what kind of wood it is? If you're replacing it, you should be asking what kind of wood you should replace it with.

 

[Utahboatnut]

Re: what type and finish plywood is this? pics inside

To me it looks like BCX or you could use ACX depends on avalability/price. If however you can find a nice piece of CDX might as well use it strength wise it makes no difference. Generally fiberglass construction consists of layered materials that are built up with resin as the binder of it all and then a finish coat of some sort. Usually you go a layer of mat(large strand fiberglass) then a layer of cloth(like fiberglass fabric) then repeat until you achieve the desired thickness. then top coat gelcoat paint etc. There are lots of different types of mat and cloth. The reason I said it isn't all that strong is because one layer of anything doesn't add much strength. In that application it would help with the ridigity of the plywood a bit and also waterproof it. Yes it is something you could do your self, any boat shop will have fiberglass repair kits or products to handle the job. Lastly there are two types of resin (binder) you can use poly or epoxy I would reccomend the poly for that job. It is much cheaper, more products are compatable with it, and boats have been built with it for MANY years with great success. If you get a kit that has everything included it will make the job easier plus give you step by step instructions on how to apply it all make sure you follow as closely as possible.

 

[ovrrdrive]

Re: what type and finish plywood is this? pics inside

who cares what kind of wood it is? If you're replacing it, you should be asking what kind of wood you should replace it with.

You know, I hate to thread crap and usually try to slam people that do, but you're absolutely right. Just replace it and go on with your life.

 

[kaferhaus]

Re: what type and finish plywood is this? pics inside

Well now after seeing both sides of it, it could be BCX... but the size of the surface voids on the first side you showed still make me believe that it was sold as CDX at the time.

BCX is a little better on one side than the other... but the other poster about the quality of recent lumber is correct... what they're calling "A" grade plywood now was "B" grade not many years ago.

In any event the long and short of it is this is for a deck..... who really gives a crap? You're not going to get any better service out of one or the other until you move up to cabinet grade wood and that's a total waste of money.

It was done on the cheap when first built and has lasted a good number of years... I'd buy come CDX or BCX, hit with some poly resin.... maybe it'll penetrate well maybe it won't and throw a sheet of mat on it.

If carpet is going over it no need to top coat it with anything.... UV is what breaks down the glass.

It'll likely last another 15-20yrs of normal use.

Personally I never use Poly on wood, but for a deck on a boat that you likely won't have 5yrs from now it'll save a bunch of money.

 

[weider1717]

Re: what type and finish plywood is this? pics inside

Well now after seeing both sides of it, it could be BCX... but the size of the surface voids on the first side you showed still make me believe that it was sold as CDX at the time.

BCX is a little better on one side than the other... but the other poster about the quality of recent lumber is correct... what they're calling "A" grade plywood now was "B" grade not many years ago.

In any event the long and short of it is this is for a deck..... who really gives a crap? You're not going to get any better service out of one or the other until you move up to cabinet grade wood and that's a total waste of money.

It was done on the cheap when first built and has lasted a good number of years... I'd buy come CDX or BCX, hit with some poly resin.... maybe it'll penetrate well maybe it won't and throw a sheet of mat on it.

If carpet is going over it no need to top coat it with anything.... UV is what breaks down the glass.

It'll likely last another 15-20yrs of normal use.

Personally I never use Poly on wood, but for a deck on a boat that you likely won't have 5yrs from now it'll save a bunch of money.

thanks to all and to the qouted above.

I went out and found some 5ply BCX plywood and bought a sheet of it. I cut it out identical to the original and tested the fit...works great!

now all I have to do is finish the wood, I'll just finish it like the original was finished since the original still looks dang decent considering this is a 1984 boat. Which I have taken good care of it and it was my late grandpa's boat which he also took very good care of.

question is we determined the carpet side has 1 layer of mat and some we assume poly resin on it. Do I put a layer of poly resin on it then while thats wet lay some a layer of fiberglass/mat on the wet resin right? then when that dries put another layer of resin on the mat correct? just wanting to know the sequence here..or do you just lay down the mat on dry plywood then put the resin.

that covers the carpet side...

the other side doesn't have mat on it and it actually doesn't look like that hard glassy looking resin. Instead it looks like just a clear varnish u agree?

I plan to just varnish that side OR I may just poly resin and mat that side as well. Not sure.

where is the best place to go that your normal town has to buy poly resin and mat? I live in a semi small town def. no major city.

thanks this forum rocks! I enjoy learning about this stuff and doing the work myself. I'm semi young 25 so just learning!

 

[grego]

Re: what type and finish plywood is this? pics inside

If you want the same finish,plus protect. you will need to give it 15 coats of clear polyeurothane,both sides, and edges! Then drill holes, and use a small paint brush to seal inside drilled holes with poly, "while still wet," Coat bolts with same and tighten. Hope I understood question!

 

[grego]

Re: what type and finish plywood is this? pics inside

If you want the same finish,plus protect. you will need to give it 15 coats of clear polyeurothane,both sides, and edges! Then drill holes, and use a small paint brush to seal inside drilled holes with poly, "while still wet," Coat bolts with same and tighten. Hope I understood question!

 

[Mark42]

Re: what type and finish plywood is this? pics inside

Why don't you just take a piece down to the lumber yard and ask someone who knows lumber and can see the piece in question.

Keep posting the same question and you will keep getting different opinions.

 

[weider1717]

Re: what type and finish plywood is this? pics inside

Why don't you just take a piece down to the lumber yard and ask someone who knows lumber and can see the piece in question.

Keep posting the same question and you will keep getting different opinions.

I've already bought the plywood and cut it to fit. u missed a post of mine a couple post above.

I went with bcx although on the better side of the original it was better compared to acx.

but they didn't have acx in 5ply so i went bcx, good enough for what amount i use the boat.

i just gotta finish it with mat and resin now and varnish which i have never used any of the 3 lol/