Different types of plywood... MDF core?

[Ben@FineWoodworking]

So I went down to Nashville Plywood today... surprisingly the only place in this city that has a fairly vast selection of plywood. I am looking to build to large bookcases for our dining room. I have the plans all done up in sketchup, cut list made up.

I figured for both cases I will need four sheets of 3/4 and two sheets of 1/2.

I had cherry in mind. Good Lord... plywood is expensive. They wanted $78 per sheet for cherry 3/4 and $61 per sheet for birch. They had Cherry MDF core for $63 and Birch MDF core for $45.

Keep in mind this is my first trip to a real lumber yard so I kinda felt like an idiot at the counter and that fear I was bugging the guy took over I probably didn't ask all of the questions I should have. They were incredibly nice... one of the warehouse guys even gave me a mini tour... I was just overwhelmed.

You guys don't scare me as much... so I'll start here.

So for just the plywood on these two cases we are looking at five hundred dollars if I went with Cherry. There is no way we can afford it... if we wait till we can... they'll never get built. I have waaayyy too much time into the design and building the jigs (had a blast doing it) to walk away with no bookcases.

Do you guys stray away from MDF core ply? If so why? I do know that I don't want to build temporary furniture. I want something I can be proud of and will be around for a long time.

Is there another type of plywood that I should be looking into? Maybe poplar?

I really just need to call them and ask them what the cheapest plywood is... that doesn't look like crap.

[bywc]

Baltic birch is my preferred choice but here is a good article on picking the right kind pretty good info really.

http://www.popularwoodworking.com/article/choose_the_right_plywood/

[Ben@FineWoodworking]

Baltic birch is my preferred choice but here is a good article on picking the right kind pretty good info really.

http://www.popularwoodworking.com/article/choose_the_right_plywood/

Great article... thanks for the link. It kinda makes me want to try the MDF core though. I am sure baltic birch would hold up better... there is just no way we would be able to afford it.

[Ben@FineWoodworking]

I should add... if it came down to having cases that would last and having to paint them and having cases that won't last but look nice... I'll paint.

[Bobby Slack]

Here is another article for you http://www.finehomebuilding.com/how-to/articles/build-better-cabinets-with-the-best-plywood.aspx?ac=fp

If you buy pre-finished plywood, no problem, if you are going to apply a stain is best if the last section prior to the veneer is MDF. That is called Classic Core. Somebody who knows about finishing can tell you why.

Good luck.

[Bobby Slack]

Thanks for this article I filed it under my "wood" folder in my computer. Is amazing how we can get great articles of magazines, the issue is to store them and find them. I try to keep my electronic files organized.

Baltic birch is my preferred choice but here is a good article on picking the right kind pretty good info really.

http://www.popularwoodworking.com/article/choose_the_right_plywood/

[Ben@FineWoodworking]

I filed it under my "wood" folder in my computer.

huh...

[Bobby Slack]

There is so much content online that I create folders like wood, joints, chairs, tables, etc. I knew about the Fine Homebuilding article but did not know about the Popular Woodworking one. I filed both articles on my database for future use.

Your question helped me improve my woodworking digital library.

Good luck tomorrow.

huh...

[Jerry_in_SD]

Except for some 1/4" MDF core ply, I generally stay away from the MDF core stuff as the veneer core is much more rigid (and lighter). I would think for bookcases you would want the rigidity of veneer core.

Your Cherry veneer ply is relatively good deal compared to what I pay in San Diego (have paid >$100 in some cases). I did purchase some pre-finished 3/4" birch ply for a built-in project I am working on now. I think the prices was around $40/sheet if I recall correctly.

[PaulMarcel]

The plywood with a thin layer of MDF under the show-side veneers has a smoother surface and won't telegraph the grain of the underlying plys. Depending on the species and thickness of the show veneer, applying a top coat might let you see the underlying veneer and that's not good. Think about it, it works like a wet tee-shirt. Well, don't think too long about a wet tee shirt

The thin layer of MDF doesn't appreciably increase the weight of a full-sized sheet or the holding power of screws since they quickly pierce the MDF into the veneer or classic core.

[Vic]

huh...

Under your "Favorites" create folders and subfolders. For instance, I have Tools >> Handtools, Veneer, Jigs, etc. and then some of those have more subfolders. Organization is your friend. I little time now, saves a ton of time later. My buddy Nabil, over on the Live Streaming/Chatroom is the king of links. I can only imagine how well organized HE is!

[Ben@FineWoodworking]

Under your "Favorites" create folders and subfolders. For instance, I have Tools >> Handtools, Veneer, Jigs, etc. and then some of those have more subfolders. Organization is your friend. I little time now, saves a ton of time later. My buddy Nabil, over on the Live Streaming/Chatroom is the king of links. I can only imagine how well organized HE is!

The pic above should show my bookmarks folder labeled "wood". It's a PNG image... might not show up on PCs. Oh ya... I am a bookmark organizing MONSTER. You should see my folder of ebay bookmarks.

[Ben@FineWoodworking]

I'm still kind of leaning towards the MDF core... I might regret it... dunno. I am going to dado the sides and backs for all of the shelves and put hardwood edging on the fronts. I think that should be sufficient for a 40" span.

Never having worked with it before I am can't tell if many just hate the idea of MDF out of principle or if it is really a bad product. I know it is messy and heavy but does it make bad furniture?

Right now it is about money. I haven't had a chance to go down there or call them. If I could find ply for $40 a sheet that would look decent we would be able to afford to build both cases. I would really prefer to build both at the same time.

Right now I have two options...

Build one... save up more money... build the other.

Or

Find another type of ply that is cheaper and paint them.

Ugg... choices.

[Vic]

I'm still kind of leaning towards the MDF core... I might regret it... dunno. I am going to dado the sides and backs for all of the shelves and put hardwood edging on the fronts. I think that should be sufficient for a 40" span.

Never having worked with it before I am can't tell if many just hate the idea of MDF out of principle or if it is really a bad product. I know it is messy and heavy but does it make bad furniture?

Right now it is about money. I haven't had a chance to go down there or call them. If I could find ply for $40 a sheet that would look decent we would be able to afford to build both cases. I would really prefer to build both at the same time.

Right now I have two options...

Build one... save up more money... build the other.

Or

Find another type of ply that is cheaper and paint them.

Ugg... choices.

The biggest problem you hit with MDF is using fasteners. Normally, you have maybe two times to screw and unscrew before the MDF is trashed. If you're using it as a panel in a piece, it should work quite well. It's very stable. Be sure to wear a respirator when you cut it. Nasty amount of dust and formaldehyde released when you start milling it.

[Pete Bennett]

I'm still kind of leaning towards the MDF core... I might regret it... dunno. I am going to dado the sides and backs for all of the shelves and put hardwood edging on the fronts. I think that should be sufficient for a 40" span.

Never having worked with it before I am can't tell if many just hate the idea of MDF out of principle or if it is really a bad product. I know it is messy and heavy but does it make bad furniture?

Right now it is about money. I haven't had a chance to go down there or call them. If I could find ply for $40 a sheet that would look decent we would be able to afford to build both cases. I would really prefer to build both at the same time.

Right now I have two options...

Build one... save up more money... build the other.

Or

Find another type of ply that is cheaper and paint them.

Ugg... choices.

MDF is a pretty nasty material if you spend too much time thinking about it in that way. Although I very rarely use it that has nothing to do with what it is. In the right circumstances and used in the right way it's very good. You've heard all the bits about it's stability etc. However until I read this last post I was concerned that one thing MDF is not good at long term is taking too much load unsupported. It sags. Books are usually much heavier in a collection than most people realize. However you are absolutely right in fitting the shelves in dados and try to make your hardwood lipping as large as you can get away with. You'll be amazed how much stiffer the shelves will be with say a 1" x 1" lip, especially if you t&g it in place.

Your question regarding people's attitudes to MDF is a bit like a lot of peoples attitude to 'veneered plywood'. I have an answer to any of my clients who disparage veneered plywood. I tell them the Great Thomas Chippendale himself often made plywood in order to make some his much raved about filligree decorations. And if that is not enough tell them the ancient Egyptians actually invented the stuff and even after four thousand years some of it is still around. That really shute 'em up.

All the best

Pete