Plywood vs Plywood...

[sjbaines]

There are a bunch of threads on MDF vs. Plywood, but of course Plywood comes in many varieties...

I'm planning on going for plywood for my cab, but stuck on deciding which type of ply I should get.
The cab is going to be black (with no sideart). I'd prefer to stain it, but if that's going to be troublesome then I'll happily paint it instead.

I've considered veneer, but it costs a lot more, seems hard to obtain locally, and doesn't play well with T-molding due to the extra thickness, I believe. This being my first cab, I don't want to spend too much on the wood in case I make a total mess of it...

From what I've gathered so far, Hardwood Plywood is usually/(always?) birch, and birch is difficult to stain, so I'd probably have to paint it to get it black, so I wouldn't be able to see the grain anyway.

If I end up painting over the grain anyway, would I be just as good using Softwood Plywood?
Softwood ply is much cheaper, but is it tough enough?
Surface finish is not as fine, but again, if I end up painting it, will that matter?

And then there's 'Hardwood throughout' plywood. What's the different between this and normal Hardwood plywood?


My local building supplies place has the following:
1. Softwood Ply, marked: 'C+/C WBP CE2+', with 9 layers. £30
2. Hardwood Ply, marked: 'BB/CC WBP MVP SDN BHD EN 13986 MTCC', with 5 layers. £47

Another supplier has:
3. 'Hardwood thoughout' Ply (no further details). £29.

(All are 2440x1220x18mm sheets).

Any comments?

[drventure]

I'm in the US so things might be a little different here 

But generally, I see "plywood" and "furniture grade plywood", Which might be what you're calling soft and hardwood ply.

The regular plywood, is very rough. You'll likely need to use a spray putty filler and a lot of sanding to get it smooth.

The furniture grade ply is usually a much smoother finish, suitable for staining. Even so, if you plan on painting, I'd seriously consider using spray putty on it too, as the grain will usually show through even several coats of paint.

As for veneer, on something flat like cab sides and panels, it'd be pretty straightforward. Veneer is typically quite thin, so it shouldn't interfere with tmold. You +might+ need to camfer the bottom edge of the panel slightly (using a 45 deg router bit) so that the bottom of the panel fits flush with the bottom of the tmold.

[Spock]

If you can get a plywood that is AA/CC at least, that would be good.  The AA/CC stands for the grade of each surface, in this case the AA being the good side (CC sides are usually not that great with knots, etc.  Good for interior.).  If you really want some good plywood, see if you can find some marine grade plywood.  That's by far the best structurally, but about 3x as expensive (but then again, I doubt you'd have this thing outside very often ).  See if you can find some decorative plywood that has a color based on the one that you want it to look like at the end.  You can find plywood in red oak, and mahogany, for example.

[Donkbaca]

Get the hardwood ply, softwood is very, well soft.  You can dent it with your finger nail  I am currently wrestling with staining some birch.  I got a conditioner and then the all-in-one poly shades.  Apaprently this is not the way to go.  The best way to stain is to condition and get regular stain, and then coat with poly.  Trying to short-cut the process like I did, doesn't work too well.

There really isn't much of a difference, really between the work needed to stain or paint.  The only advantage to painting is that you can use wood filler and not worry about it matching, as you do when you stain.  In both instances you need to make sure that you are finishing a nice, smooth, even surface.  A common misconception is that the paint or stain will hide any imperfections.  They don't, in fact they tend to magnify any issues you have in the wood.

I would say go with the better grad plywood, its surface is already sanded smooth and will take a lot less work to finish.

[sjbaines]

I'm in the US so things might be a little different here 
But generally, I see "plywood" and "furniture grade plywood", Which might be what you're calling soft and hardwood ply.
The regular plywood, is very rough. You'll likely need to use a spray putty filler and a lot of sanding to get it smooth.

Hmm. Could be. At least to a visual inspection, the surface of the softwood looked decent, but maybe it's not so easy to tell just be looking.  There's also 'shuttering plywood', but that's really cheap stuff, which I believe is just to box in areas that you are going to pour concrete into. Hmm, concrete cab, there's an idea...  .

Anyway, sounds like a vote for the hardwood...

[sjbaines]

If you can get a plywood that is AA/CC at least, that would be good. 

Seems hard to find anything better than B/B, and I'm guessing that A is going to have a serious premium over B anyway.
My understanding is that B grade allows some small defects, whilst A allows none. Since I'll be cutting up the sheets then there's a fair chance (though no guarantee) of being able to avoid the bad bits anyway

If you really want some good plywood, see if you can find some marine grade plywood.  That's by far the best structurally, but about 3x as expensive (but then again, I doubt you'd have this thing outside very often ).

Yeah, the only place local that lists marine grade has it as 'price on application', which I take to mean 'expensive'...

[sjbaines]

Get the hardwood ply, softwood is very, well soft.  You can dent it with your finger nail  I am currently wrestling with staining some birch.  I got a conditioner and then the all-in-one poly shades.  Apaprently this is not the way to go.  The best way to stain is to condition and get regular stain, and then coat with poly.  Trying to short-cut the process like I did, doesn't work too well.

Ok, another vote for hardwood.  If I do end up with birch then I might want to exchange thoughts/experiences on staining, if that's ok.
Certainly it seems that I'd need to try out a bunch of test samples on scraps, at the least.

[Fursphere]

I just built three cabinets out of "cabinet grade" plywood from Home Depot.  I wouldn't use anything less.

To get a decent finish, it required about 6 coats of there most expensive paint ($15 / quart) and sanding inbetween coats.  And its still not perfect.

The wood grain will "lift" every coat, so you have to sand it back down after its dry.  A lot of paitence will be required. 

[shrunkenmaster]

I'm in the UK my man. Although ply is lighter, I'd go for MDF for a cab anytime. It's so much easier to work with, if you can withstand the dust when cutting.

It's so much smoother, although you'll still need to sand/prime/paint for a good finish. Otherwise, use self-adhesive vinyl (which is a cheaper and quicker alternative to lots of sanding and painting) if you just want a plain black finish. I've used this before and it looks as good as the day I applied it - after all, it's not gonna be in a real arcade and subjected to a right battering...

You only have to give the MDF a good high grit sanding (400-600grit) then apply the vinyl, no messing about priming and painting. Check the link in my sig (Mystery Machine) for a UK supplier of this vinyl on eBay.

Hope this helps.

[The Lumberjackass]

my reccomendation is to use with mdf. it'll work much better with your longterm plan.

using plywood for a cab is overkill, and not needed unless your building a cab which will be subjected to harsh treatment. also, if you do decide to stick with ply, dont use any softwood types. even if its a high quality, it still has the properties of a softwood.

mdf will work with either paint or vinyl , machines easily and has good strength. its the 1st option i always go for.
you can use the ply if you really want to, but i'd say go with mdf. so what if its dusty to work with, isnt that what vacumn cleaners are for

[sjbaines]

Ok guys, I think you've converted me back to MDF...

I have actually bought some hardwood plywood which I was planning to use - but the surface is somewhat 'lumpy' in places (quite a few small but noticeable ridges and ripples), plus its got an extremely thin surface veneer, so if I tried to sand them out then I would sand through the veneer. Hmm. (This is the 'Hardwood Throughout' option 3 from my original post). I think these sheets are now going to get used for shelving instead.

I was looking at some more expensive stuff (Option 2 from my original post) that I've actually had chance to inspect, and it looks a lot better.  But, it's pretty expensive, and I'm starting to get a bit concerned with the number of people saying that getting a good finish on ply is a lot of work, even with good wood.

So, since I've got minimal woodwork skills, this is my first cab, there are other complications to the design (rotating CRT monitor), and I need to be finished by June, I think that I just need to deal with the dust, and go with MDF after all.

I certainly like the idea of a nicely dark-stained wood cabinet, but it's increasingly looking like I'd struggle to get a good enough finish, and the MDF + paint or vinyl is now looking like the better (more realistic) option.

Thanks for your input.

   Cheers - Steve

P.S. Mystery Machine looks very nice - that's kind of similar to what I'm going for, except mine will be smaller!

[Woodshop Flunky]

I've not built an arcade cab, but I have used ply and MDF for quite a few projects.  For my build I'm most likely going to use ply and then laminate it with black Formica.

Don't hesitate to paint ply.

1. I stick with Baltic or Russian Birch (lots of plys, and next to no voids).  You will NOT find this in a big box store in the states, but a local cabinet shop should be able to set you up.
2. Put down a water based primer first.  This will "raise" the grain (the surface will feel rough).  The tiny wood fibers have actually curled up at this point.
3. Let the primer dry (water based primer dries really quick) completely and then sand with 220 grit.  Do this a couple more times and you're in good shape to start painting.
4. Between each coat, get your eye down really close to the wood, and look down the length of your work with a light source at the other end.  This will let you really see if there are any imperfections.
5. After this, your ready to start painting.  The finish you achieve at this point is dependent up how willing you are to apply coats and wet sand between.

Honestly, I would follow the same process with either MDF or ply, so it may boil down to cost or availability of materials.

Just my 2cents.

[deadmeat]

I used cabinet grade birch ply on my cab and it came out great.1 coat of primer, 3 coats of satin black paint with no visible grain. I was gonna use mdf but after a saw it in person it seemed too " wobbly" and its HEAVY.

[DNA Dan]

I am trying to decide between MDF or plywood as well. MDF is great to work with, but as others stated it's quite heavy. Also it's not really available in 5/8" in my area.

My concerns with plywood are the channel bit routing for the t-molding. Those that have done it, do you get layers interfering with the t-molding installation? Do the layers chew out on corners?

I looked at the Wilsonart laminates and home depot quoted me ~$50 a sheet of 4X8. I figure two sheets should just about do it. It's probably twice the cost of painting/sanding, but in terms of time, it's significantly less and might be more durable as well.

[Blanka]

Birch is no hardwood: it's very soft. The hardwood versions have much courser grain, so they paint badly, but they are also available pre-primed.
Best stuff is Poplar Plywood. Nicest stuff they make. Almost a pity to cover it.

[Donkbaca]

Birch is a hardwood. Hardwoods are any tree that loses it's leaves. It's Nat a measure of how dense the wood is. I am using 3/4 inch birch. You just need to be a little more picky when selecting the wood to make sure it's not warped. The t-slots route fine, and are easy to measure too, you just route the middle layer

[Blanka]

Did not know english use the term "hardwood" for "leaf-wood". Here hardwood is wood with a certain physical strength and durability. Azobe, Okume, Rubina, Oak, Bankirai, Meranti etc is what we call hardwood. Therefore the only "hard" plywood you can get here is Meranti or Okume. Okume comes in a pre-painted flavour too.

I wonder how you translate the campaign we have against "Fout hardhout" ? Bad "hardwood" from illegal harvesting in Indonesia and Brazil (non-FSC hardwood). Anyway, hardwood is a nice word to catch a bad translator! Dutch-German is easier, as we think the same about Hartholz.

[Donkbaca]

Haha, I didn't know that about hardwood either, I read about it in some wood working books I got.  It says that trees that lose their leaves, like oak, and birch are hardwood and that evergreen trees are soft wood, like pine.  Its just a way they classify the wood and has nothing to do with strength.

[Captain_Dingo]

Haha, I didn't know that about hardwood either, I read about it in some wood working books I got.  It says that trees that lose their leaves, like oak, and birch are hardwood and that evergreen trees are soft wood, like pine.  Its just a way they classify the wood and has nothing to do with strength.

This is correct.  As funny as this is going to sound, balsa wood is a hardwood...

[jimfath]

Haha, I didn't know that about hardwood either, I read about it in some wood working books I got.  It says that trees that lose their leaves, like oak, and birch are hardwood and that evergreen trees are soft wood, like pine.  Its just a way they classify the wood and has nothing to do with strength.

Yes. deciduous trees (Leaf bearing) and Coniferous (needle bearing or pine) trees grow at vastly different rates. Pine trees grow much much faster and the wood is less dense and much softer. And there you have all that I remember from 7th grade biology.

[Blanka]

If you want to paint, go MDF, MDF or just MDF.
Seriously, painting MDF compared to plywood is like sex in the nineties vs sex in the seventies.
Biggest problem with MDF: people use 18mm thickness all over, where 12 is right for most parts.
And if you want plywood: get plywood with MDF top layer!

Don't be fooled by wood-prices: PAINT IS ALWAYS MORE EXPENSIVE! So the crappier the wood, the more you spend on paint.

Always fun the hardwood thing between english nations and the dutch/french/german interpretation.
Hardwood in English is from a tree that looses its leaves. We call that leaf-wood.
Hardwood in NL/D/F is wood from a tree with a high stability against rot and micro organisms. Not birch, but oak and most tropical wood.

[apfelanni]

hardwood in germany is per definition wood with more than 550 kg / m³ , softwood with less than 550 kg / m³ . most coniferous wood is softwood , most deciduous is hardwood. hm .. im gonna ask my bro in canada how the newworlders handle the terms . hes working in a sawmill in houston b.c. , one of the biggest sawmills on this planet. i've been there 3 weeks ago .

btw. did u know that germany is the number 2 wood supplier ( after canada ) on the us market ?