mdf core ply or vc ply

[Andrew Hughes]

I dont buy alot of sheet goods.So i am not sure what i a better choice top for a stand up drawing table.The top will be adjustable 60inch long 36 wide.The table is walnut so the ply will be banded with walnut.My suppler suggested his gold line mdf core walnut ply.My concerns are weight and flatness from sagging.The table is 43 inchs tall and weighs alot already.my other thought was A1 walnut ply.The A1 is about 40$ more.And i am at the end of the budget for materials.
What do you think?

[Tony Bilello]

Definitely go with the plywood.
Unfortunately, budgets and 'concerns' dont always agree. You just have to view it as a one time purchase that will span a lifetime.
You will feel better about the MDF at time of purchase and then resent it forever after.

[Chip Lindley]

For a drawing table, go with ply-core! Stronger and Lighter too! High-grade walnut veneered ply should be plenty flat for your purpose--Not like the BORG hardwood ply many encounter.

[Paul Ryan]

I personally dont like the MDF plywood because it makes a mess when you cut it. It dont think it glues decent. And it is stinkin heavy. But it is usually really flat you dont have to worry about warping as much.

[Frank Drew]

Either veneer core or fiber core would benefit from adequate support and bracing to prevent sagging or warping.

MDF is heavier than vc but does often arrive, and stay, flatter, at least in my experience; I don't particularly like working with it (mdf), but with the provisos stated above about support and bracing, I can't think of a strong reason not to use it for a drawing table.

[glenn bradley]

The A1 is about 40$ more.And i am at the end of the budget for materials. What do you think?

I think I would look at the time and money I already had into the thing and ask if $40 was worth not finishing it up well. I'm not being a pill. This is a question I have to ask myself from time to time when things go over budget. The times I have "made do" haunt me every time I see them :mad:. Go with the ply.

[Walter Plummer]

If the table is going to be used a lot you should consider using the normal green vinyl material for the drawing surface itself. Cover the field and show walnut around it. Google drawing board covering, they sell it in rolls,set sizes, and some suppliers will cut to fit. If it is more for show but still get used the mdf will be a lot smoother to draw on. No grain for the pencil to fall into and no plywood core telegraphing through the finish.

[Jim O'Dell]

I'm going to be the stinker here:rolleyes:....if the 43" span is not supported well, neither one is going to stay flat. But if that's the case, I'd go with a base of 3/4" ply for rigidity, and 1/4" MDF on top with what ever finish layer you choose. I agree that the special drawing surface would be best. Even the Walnut veneer will have some grain to it, and the pencil will try to follow it. The 1/4" won't add too much weight, and it should help with the flat drawing surface. You could bring the banding up to be flush with the top surface. Only think I don't know is if bonding the MDF to the ply will cause a problem. :confused::confused: Maybe let it float within the border of the Walnut trim? Just some off the hip ideas. Jim.

[Rob Fisher]

If the table is going to be used a lot you should consider using the normal green vinyl material for the drawing surface itself. Cover the field and show walnut around it. Google drawing board covering, they sell it in rolls,set sizes, and some suppliers will cut to fit. If it is more for show but still get used the mdf will be a lot smoother to draw on. No grain for the pencil to fall into and no plywood core telegraphing through the finish.

Vyco is one of the prominent board covers. It is great stuff, helps prevent broken pencil points and holes in your drawing paper.

Rob

[David DeCristoforo]

MDF = Most Definitely Funky (or any other word you want to put there that begins with the letter "F"). Why anyone would want to use this stuff for any quality woodworking project is beyond me. "Gold Line" MDF?!?! In the interests of maintaining civility, I will say no more about that. As Mark Twain said, the curtain of charity is drawn here. Besides, you would probably need a bumper jack to raise and lower the top.

[Andrew Hughes]

Thanks for the responses.I will go with the A1 vc ply and never mention mdf again.The customer will be using the table for estimating bids on measured drawings.But i will mention the drawing mat if he starts poking holes thru his papers.

Bye

[Rich Aldrich]

If you use pocket screws, MDF core will not hold pocket screws. You need plywood core for pocket screws.

[Frank Drew]

Why anyone would want to use this stuff for any quality woodworking project is beyond me.

I've use it as a substrate for veneer on "quality" work I've done.

[Joe Chritz]

I wouldn't rule out MDF core material for everything. For what it is designed for it is very good stuff. You do have to purchase a quality grade and that may or may not be what is available at the home center.

Essentially MDF core plywood is just a big veneered panel someone else lays up for you with really thin skins.

In your application proper sub structure is going to be important no matter what you use and either will serve fine.

That said I generally save MDF / PB core sheet stock to basic cabinets and try to use solid wood whenever possible.

Joe

[Sean Nagle]

My local supplier carries a combo-core product that uses veneers for the central core and then has a layer of MDF beneath the outer veneer. The MDF layer assures a very smooth substrate for the outer veneer. It also weighs less than an all-MDF core plywood. I've used combo-core plywood for case goods and I do like it.

[Frank Drew]

That's interesting, Sean, I've never seen that product. It might solve the issue of no grain strength with ordinary mdf, while, hopefully, not warping like so much vc.

On let's say a 3/4" panel, how thick would the inner veneers layer be?

[David Helm]

Just put a new top on my drawing table. I used 3/4 inch MDO (medium density overlay) plywood for the top. It's an excellent drawing surface and the ply is quite strong.

[Leo Graywacz]

My local supplier carries a combo-core product that uses veneers for the central core and then has a layer of MDF beneath the outer veneer. The MDF layer assures a very smooth substrate for the outer veneer. It also weighs less than an all-MDF core plywood. I've used combo-core plywood for case goods and I do like it.


That's interesting, Sean, I've never seen that product. It might solve the issue of no grain strength with ordinary mdf, while, hopefully, not warping like so much vc.

On let's say a 3/4" panel, how thick would the inner veneers layer be?

There are two companies producing such a product (probably more) Columbia and Norboard come to mind. Columbia produces Classic Core (http://www.columbiaforestproducts.com/Products.aspx/ClassicCore) and Norboard produced FX (http://www.packardforestproducts.com/pdf/FX_FX-P_Brochure.pdf). Both products can be bought with or without the a veneered layer on the outside. So you can have a lighter flatter substrate for doing a nice paint job. This is important as you go beyond satin. If you go to gloss I would still use straight MDF as the cores of the combo board can still show large waves.

[Jim Becker]

MDF Core is great for built-ins, etc., but I'd go with the VC for your stated project. Lighter in weight, too.

[Dennis Hook]

My local supplier carries a combo-core product that uses veneers for the central core and then has a layer of MDF beneath the outer veneer. The MDF layer assures a very smooth substrate for the outer veneer. It also weighs less than an all-MDF core plywood. I've used combo-core plywood for case goods and I do like it.

My supplier carries this same product and calls it "gold ply" which might be what Andrews supplier was suggesting. It is a great product, sort of a best of both worlds. I enjoy working with it. There is a product line that is a solid MDF core with veneers applied which I avoid at all costs.

[Sean Nagle]

That's interesting, Sean, I've never seen that product. It might solve the issue of no grain strength with ordinary mdf, while, hopefully, not warping like so much vc.

On let's say a 3/4" panel, how thick would the inner veneers layer be?

Frank, I searched my shop looking for a piece of scrap to photograph and measure the inner core, but I could find any and I'm not using any for my current projects. Sorry I don't have that information.

[Leo Graywacz]

That's interesting, Sean, I've never seen that product. It might solve the issue of no grain strength with ordinary mdf, while, hopefully, not warping like so much vc.

On let's say a 3/4" panel, how thick would the inner veneers layer be?

Just look at any normal plywood, it is comparable to that. The outer layers are replace by MDF instead of veneer core. Then it is veneered with your choice of species.