Replies

1. 
   JeffHeath | Feb 24, 2009 06:17pm | #1

   Bending ply over a form in a vac bag is definately the easiest, but not the only way to skin that cat. 

   You could also build a top and bottom form from mdf, and make a 'press', with the thickness of the piece in question removed from the radius.  Bending ply for the substrate, with veneer on top and bottom.  Veneer the edges after. 

   Lots of clamps and cauls, and you'll need a glue with alot of open time, like plastic resin glue.

   If you do, or plan to do, more of these in the future, then the vac bag is the way to go.  Time is money.

   Jeff

1. 
   JBDesigns | Feb 24, 2009 07:55pm | #3

   Thanks Jeff,It's probably not even possible without the bag. If I did go with the bag, how would you make up the mdf part? 30 1" mdf arches screwed together? If the bottom is mdf with veneer, then the top would have to be also, right? Movement and all?Anybody with thoughts on a ballpark price?Thanks,
   Justin

1. 
   JeffHeath | Feb 24, 2009 08:46pm | #4

   Me......I take no chances.  I would build it solidly out of mdf, all the way across, and line it with cork.  That's what I do.  Other's will tell you to build a webbed frame, and attach several layers of bending ply over that to do the same.

   Just so you know, you can make it without the bag.  I've done it many times before I had the vac bag.  It's just more work.  With the vac bag, your jig is half the size (half as much work) and you can easily duplicate it for future orders.

   As far as price goes, whatever the market will bear, and then add 20% to 30% to that.  I'm expensive, but I'm a damned good salesman.  So, I can't help you much there.

   Jeff

2. 
   JiminFla | Feb 25, 2009 06:19pm | #5

   Jeff,I have never used bending ply. Would the veneers be enough to keep it from bending when weight is applied to the top of the table?Jim

1. 
   JeffHeath | Feb 25, 2009 06:27pm | #6

   The idea is that you will be layering a several layers of bending ply, completely laminated with a proper glue (I use plastic resin-urea formaldehyde glue).  It's just like doing a normal bent lamination out of resawn stock.  Once the glue dries, the bending ply and veneer is now dried in place, with the glue holding it. 

   It's hard to tell, but it looks in your picture like the thickness of those bent table components are between 1 1/2" to 2" thick.  That will be plenty of layers of bending ply to create enough strength, assuming you won't be sitting a concrete sculpture weighing 500 lbs on the table!

   Jeff

   Edited 2/25/2009 10:27 am ET by JeffHeath

1. 
   JiminFla | Feb 25, 2009 06:36pm | #7

   Thanks, now I understand.Jim

2. 
   curtg | Feb 24, 2009 06:17pm | #2

   Ignoring the customer's request for solid materials, I would build two torsion boxes and veneer the surfaces.