veneering an oval top

[Eric John]

good morning,

so latest project im working on is an oval coffee table. top is 23 by 48. i would like to do a sunburst veneer top.
but ive never glued down a top this big. im wondering if if its time to put down the veneer hammer.
im not sure if mdf platens and clamps are the way to go, or is it time to bite the bullet and get a vaccuum press.
or stick with the hot hide glue and use an iron if i get any bubbles. what would you guys do?

regards
eric

PS. thanking all of you for your help in past, what an awesome place to go for help and advice

[Phil Mueller]

I guess it depends on how much larger veneering you plan to do in the future. For less frequent projects, you may want to check out the veneer press systems by Roarockit. They offer a bag size that would accommodate your project. Several of us here at SMC have them and use them and they work very well at a fraction of the cost of a vacuum pump press system, and are easier to deal with than platens, cauls and clamps.

[Richard Coers]

A conference table I made was 4'x12'. I ordered the top sheet laid up from an architectural veneer shop. I made the top of the table as a torsion box and had to glue it all up. I built a 16" high grid on the shop floor to have a flat work surface. Then laid up the sandwich of two 3/4" sheets and the grid in the middle. To get clamping force in the center of the 4x12, I used 1x4s between the melamine cover sheet and the ceiling of my shop. The 1x4s were cut 3/8" long and I bowed them into place like long springs. I was in an old warehouse, so the concrete ceiling made it easy to just put the springs in randomly. But going up to ceiling joists would work equally as well. The glue up went perfectly.

[Mike Henderson]

One thing to watch for when laying a sunburst veneer is the glue you use. If you use a water based glue, and you're not really fast, the veneer will absorb some of the water and expand. And when the veneer of a sunburst expands you have a mess on your hands (it will no longer lay flat).

Make sure you use a glue that is not water based. I successfully laid a sunburst of waterfall bubinga on a table top with slow epoxy. This was after the first attempt failed using a water based glue.

Mike

[John TenEyck]

Make your own vacuum bag. I have two I made out of clear 20 mil PVC sheeting I buy from my local boat canvas place, but you can get it from McMaster Carr, too. You can glue PVC sheeting with pipe cement. Joe Woodworker sells bag penetrations for $10 - $15. You can have a giant bag for less than $100. The bag I made 20 years ago is still going strong after many, many, many pressings.

For anything very large a vacuum bag eliminates the gymnastics that Richard had to go through.

Mike, I don't understand why WB glue gave you problems with the starburst. With a starburst I would put that veneer panel down on my caul, apply glue to the substrate and then lay that on top of the veneer panel. Then I'd apply glue to the top of the substrate and then lay the other veneer panel on it, cover it with window mesh, and slide it into the bag. Epoxy definitely eliminates any water swelling issues, but I'm not sure it's necessary with this sequence. Can't argue with not wanting to take chances, however, after putting in all that time laying up a starburst. Hmm, maybe I've just talked myself out of using WB glue for that project!


John

[Kevin Jenness]

I've seen a failed starburst layup with WB glue that didn't get pressure fast enough-ugly, and that was in a shop that specialized in veneering. You definitely need to work quickly, maybe one side at a time. Unibond 800 has less water than most plastic resin formulations. Epoxy is water free, but often bleeds through and forces a full epoxy seal coat- not a bad thing, but a step that has to be accounted for. I suspect hot hide glue would court disaster if laying the entire face at once, but doing it in sections and trimming the overlap would probably work.

A vacuum press is an investment, but if you are doing much veneer work it is a worthwhile one. As John says, you can make a bag or frame press cheaply and used vacuum pumps can be found on ebay. Add some hose and fittings and you can have a basic setup for a few hundred ameros.

[Phil Mueller]

You may also want to consider this “iron on” method shown in this video:

https://youtu.be/7G9FLX2mMBA

[Don Stephan]

Later this summer I will be doing a 48" diameter 24 piece starburst, and will have a three ply on each side, to better stabilize the multiple grain directions of the starburst. But some use a 2 ply with starbursts, some just a single ply. I used yellow glue once, every other pressing was with urea formaldehyde, aka plastic resin glue.

[Mike Wilkins]

Never done a sunburst before, but I have laid up a veneer pattern in a piece meal way. Glue it up in sections and take some of the stress out of the equation. I have seen magazine articles in which it is done this way.
Never had a problem with water based adhesives, but likely because it was done in sections.
Good luck.

[Harold Patterson]

Another option would be to use liquid hide glue. You could use cauls and clamps or make the investment in a vacuum bag. You can make the bag yourself from 20 mil pvc as another creeker said. I think the sheeting I used for my bag was 54 or 56” wide. It was so long ago I would have to measure it. It is still going strong after about 10 years.

[Carroll Courtney]

Just for giggles & grins make your own bag just to see if you like it. HD sells clear plastic for doing slabs. Cut you piece over size and buy yourself some of that gorilla double sided tape and tape the seams together. Open end where you put your project in,just fold it over couple time then put 1/4 x 2" wood strips on both sides and squeeze clamps. I have vinyl bag I may sell, just can't make up my mind on it.Plus shipping I think may be killer