Building Ash Table Using Plywood Core – Thick Veneer?
I’ve been reading about some of the techniques to do counter tops, putting hardwood on plywood, and getting predictable results. Likewise some companies building tables for restaurants, and it sounds like veneer but in a heavy duty way. It seems using plywood at the core of a table could provide some benefits as far as keeping it flat, reducing cost, and providing substantial strength, when you want a thick table top.
I’m planning to build a 6 foot table using 4/4 Ash over two layers of 3/4 inch birch plywood. On the bottom I’ll use some thinner ash. I’ll put a 1”x3” border around the entire table. I’m planning to use Titebond III but am wondering if it would be better to use contact cement to allow for a little movement. My questions are the following:
1. Is this all a bad idea? I couldn’t find any examples of this being done.
2. Would you use a different approach, or different glue to allow for wood movement?
3. Alternatives?
Ive built one this way, but I’m concerned about the long term performance. Here’s a couple pics.
Thanks in advance for your advice. I posted a wile back on a creative design for a waterfall kitchen island that came out fantastic. I’ll post pictures soon.
Replies
Veneer is just a term used for an outer covering, it can be any thickness or any material.
Now that that's said. If you want to cover a stable substrate like plywood or MDF, you can usually use any thickness of veneer up to 1/4" or sometimes 5/16" without having to worry about solid wood movement. The veneer being thin doesn't have enough potential energy to overcome the adhesive and move. When the veneer gets thicker, it can overcome the adhesive and move, resulting in swelling, cracking, etc.
If you use 4/4 ash, it doesn't matter what it's glued to, it's going to move. Probably pulling the top layer off the plywood.
You table looks to be about 32" wide. Ash that wide in the orientation you have it (has the potential) to move roughly 1/2" or more. it doesn't mean it will but it can. If the wood and the plywood core don't ever change humidity, you'll be fine but I would use a much thinner veneer to avoid issues.
Also, don't put edge banding the way you show it cross grain to the table top made of 4/4 material. It is a formula for disaster. Doing so will likely be OK if you use thin veneer. I'm surprised that Ed said 1/4" would be OK but I'm no expert on the limits on veneer thickness. I would have guessed that 1/8" is about the limit.
Thanks for the input. I’m not sure I follow on the edge banding. Are you referring to the ends where the grain is crossing over the grain of the boards that make up the top?
Ed,
Thank you for your input. So my only good option is to go to a thinner veneer it sounds like.
On the topic of wood movement, I’m planning to use the legs in the picture below. Now I’m concerned that if they are bonded to the rest of the table top I may run into problems there too. Sounds like I may need to use fasteners instead. I was hoping I could use some dominoes and glue it. Thoughts?
2 questions; why contact cement & what are you going to lift the table with - a block and tackle?
Fair points. The client wanted 3” thick solid boards end to end for a butcher block look and feel. I’ve done a number of them, however it’s not a great use of timber seeing is most is hidden from view and expensive. I suspect it will be quite heavy and I have used a block and tackle on a few of the larger builds. Not a great method. I’ve actually converted a motorcycle lift for use with some builds. It’s a cheap way of getting some hydraulic lift under the project. I’m always looking for a great solution that would let me pivot the build on its side as well as lift and lower. I’ve seen what Rockler and Woodcraft offer, and they aren’t sturdy enough. Those are really intended to move sheet goods. Moving the work is an issue when I’m alone in the shop.
On the contact cement, I’ve read where it’s widely used with veneer. I assume that’s to reduce bleed through as well as account for some movement but I may be wrong.
Below is a 6’ by 35” table top made from 6’ x 3” 4/4 boards in Ash, Jacobs, and Padauk. Finished with Odie’s Oil and Butter. That one weighed in at about 170lbs for the top. In one picture you can see the leg stretcher which was all Padauk. The kegs were solid ash 4” x 5” roughly. Each leg was about 30lbs.
Why bother with the plywood at all? Inch thick ash is plenty heavy for a tabletop, although the end skirts will fight with the tabletop and the butt-joined corners will fail. Nothing to stop you from brick-building the end grain ends to get to the depth of the side skirts.If you added 6 inches of blocking someone seated at the end of the table will never feel it.
MJ,
Thank you for the thoughtful reply. But you’ve surpassed my woodworking vernacular regarding blocking and building up the endgrain side skirts. I’m not sure what exactly you are suggesting. Also you mentioned the bug joints failing. Are you referring to the picture of the ash table? Thanks again and appreciate the schooling on this.
I was suggesting getting to your thickness at the ends by adding material in the same grain orientation as the body of the table so it would move with the table and not try to hold it from moving. Yes, I was referring to the image in your original post.
You'll be better off if you literally veneer the top/bottom with ash sliced to < 1/16th of an inch. It will do a few things for you. First it will lower the total weight. Unless the table needs to be so heavy for some reason. Second, you will avoid all the wood movement issues you are otherwise needing to be concerned about. Third, you won't need to use quite so much wood to get the net effect of an ash table.
Contact cement is generally not a great idea, although if you used paperbacked veneer it could be ok. Cauls or a vacuum press will always be a better solution but they are a potential investment.
Lets re-set a little.
If the goal is only the "look" of a thick table, then you can do all sorts of things. Does it need to be solid? Make a torsion box and veneer it with 1/16" or 1/8" or what ever. I agree with 6901980 and the ends can be done as MJ mentioned or make a faux bread board.
Contact cement is fine for store bought "paper-backed" veneers. These are 1/64" or less these days. The contact cement is usually to keep them from sliding when glue is curing since they are so thin and fragile. Set it, roll it and walk away.
As I said above, you could probably go up to 1/4" but 1/8 would be enough to give the look and have enough thickness to be able to sand and work as you would solid wood and use standard PVA glue.
At this point I am rethinking the whole approach. I have built the legs already (photo) so the question is on how to attach. I’m thinking I’ll use Festool connectors and dominos. Should allow for expansion
The goal is to have a thick strong top for the look, and function. One that a couple people could stand on frankly. In fact at one point two people will be standing on the table. It will be used in an undisclosed movie shoot, and then possibly auctioned off, I’m told. In the entertainment business, reality often falls short of the aspirational stories, none the less, strong and thick is a theme. So maybe I’ll look to use some 5/4 ash planks with a deep border on the sides aligned to the depth of the table legs. Maybe run a couple supporting boards end to end to seat the connectors into. That should meet the needs and have the integrity necessary.
Again thank you for taking the time to provide your input, it’s pretty awesome to se the effort people are willing to put forward for the average aspiring woodworker!
Used in a movie and then discarded… why go through all that trouble? Buy a sheet of ash plywood and build a skirt around just like in the picture.
I applaud your willingness to seek advice. It may be worthwhile to read more about veneering because there are ‘constraints’ as to the thickness and sometimes to the width of the veneer pieces. Unless you are using paper backed veneer the general consensus is to avoid contact cement and use a suitable veneer glue. Do you have a vacuum system and bag to clamp down on a surface as large as your table? As you can see, there are several areas of knowledge required. There are good alternate suggestions noted above. Live, work and learn.
Yes thank you very much. Certainly more research required on my part. I’ll stick to my more traditional table builds for now. The feedback has been great in helping me understand where more research is needed. Interestingly reading up on techniques used by people doing kitchen counter tops and islands, as well as companies doing restaurant tables has been interesting. Many are doing things that on the surface seem to conflict with long standing principles as discussed here. Hard to know the longevity of those builds, or if they are finished in such a way as to prevent any change in moisture but I doubt that. I’ll be sure to come back with anything worthwhile. Thank you again for the feedback!
Lets stop fo a munuite.What are you trying to achieve?A table you can sit at,move when necessary,and have a butcher block look.You can use 3/4 or 1 inch birch ply for the base.Decide the width of ash that provides the faux butcher block look/Rip it and plane it to 1/4 inch thickness,enough for top and bottom.Create the first and last pieces to the width you need to contribute to the look of the side.thickness.Miter the end of the top "veneer"so as to apply mitered pieces to the end the length of the side piece
In my estimation it seems like a project designed to use material on hand.Why not just glue up the wood you have like a butcher block?
Paul, check post #11, he states his intentions.
If you want to use a solid wood top, and pieces around the edge to make it look thinner, there are a couple ways to make the glue joint disappear and give a solid wood appearance. Many years ago we made several counter tops from a couple curly maple boards, by resawing them and sanding to 1/8" thickness. We applied them to 7/8" plain maple (and made the mistake of using water based Titebond, instead of epoxy; we got some distortion from the water hitting the solid maple.) We applied boards to the bottom edges of what would be the outside boards of the top when glued up, then applied veneer (edge banding) to the edge. Trimmed it flush. We also applied pieces of solid wood to the ends of all the boards, that were the desired final thickness, with the grain oriented the same as the long boards. They were rabbeted and glued to the ends of the 7/8" boards so there was no glue joint visible. (This made the boards longer, which we had planned for.) So now we had 6 maple boards with ends thickened, and two with edges thickened and veneered. We applied the 1/8" veneer to the tops of all the boards, jointed them, and glued them up, and trimmed the ends to final length. To make the glue joint between the top veneer and what was below it disappear, we put a larger ball bearing on a large round-over bit, and made a "thumbnail" edge (partial round over) with the resulting "hard edge" right at the glue line. Totally disappeared! In other circumstances, we have used a beading bit, with the inside corner right at the glue line, with equally good results.
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