Replies

1. 
   Beasley7 | Aug 22, 2020 09:38pm | #1

   There is nothing wrong with your design as you described it. You are essentially laying down really thick veneer. A quarter inch seems about right. A good layer of a good glue should be able to overcome the stress from movement. The walnut feels like it should be OK. Four inches isn't so wide that you get a lot of movement but we can do the math. The dimensional change coefficient for flat sawn black walnut is .00274. Not sure where you live, but assuming the table will be in a climate controlled area the moisture content change will be 3 - 5% so lets call it 4%. So 4 inches X 4% (not .04) X .00274 = .04384 inches or about 1/25". It's your call if you think that's too much; I don't.

2. 
   Eideann | Aug 25, 2020 12:59pm | #2

   Hey dusty

   Actually 1/4 is likely too thick! At that thickness its not veneer anymore it's just thin stock. You are likely to have problems down the road with cupping. You still have a fair amount of movement happening at 1/4". I've personally made this mistake before using an mdf substrate.
   1/8 of an inch is really as thick as you should go with a veneer surface. You may also want to do the same to the underside. Not just for looks, but this will balance out the pressures of the wood as it moves. Rule of thumb is if you veneer over a substrate (mdf or ply) you should do both sides. However this would balance out your dimensions (3/4 ply +1/8 +1/8 =1")