Replies

1. 
   1woodmaster | Feb 22, 2009 12:01am | #1

   Hi Neil,

   What size is the piece of veneer that you are trying to flatten? The way to flatten veener or wood in general is to heat up the lignans so that the wood relaxes.  While the lignans are relaxed, sandwich them between two pieces of flat wood and let them cool.  It is the same principal that is used in steam bending.  There is a really good veneer guy in Minnesota by the name of Tom Schrunk.  I'm sure if you do a search for him either in FW or Google you will see his work and get contact info.  I've talked to him about flattening veneers and he uses a microwave for pieces that will fit inside.  Otherwise an iron works fine.

   I don't have all of the details of what you are trying to do, but from what I know, I would glue the veneer to a piece of 1/8 or 1/4" sheet goods and frame it from there.  I was at a demo about a month ago where they took hide glue and rolled it on a board.  They also rolled it on the veneer which was a little curled up.  Then they let the glue dry on each individual piece.  The veneer was placed on the board with the two glued surfaces against each other.  A lightly damped towel was placed over the veneer to protect it from direct contact with the iron.  It just took a minute or two of sliding the iron over the veneer before it was fastened securely to the board.  It was perfectly flat and the glue bond was perfect.  The nice thing about this is that you just have to iron the veneer to remove it or relocate it since hide glue is moisture and heat sensative.

   Scott

2. 
   DonStephan | Feb 22, 2009 01:54am | #2

   I have flattened veneer using flattening solution.  Can buy pre-mixed, or 3 parts water, 2 parts white or yellow glue, a part liquid glycerin (from pharmacy), 1 part denatured alcohol.  Wet veneer liberally.   Fiberglas screen on each side for the first 24 hours so drying paper doesn't stick.  Newspaper on each side, changing about 4 times first day, several times each additional day until the veneer dry.  Consider moisture meter to know when "dry". 

   If brittle, slowly apply pressure - may start simply with cover piece of 3/4" plywood, then gradually add weight until flat.  Vacuum bag can be great way to "clamp" or other means.

   Once dry, can glue to cross-band backer.  After adhesive cured, the two ply should be more than stiff enough to sand, even with random orbit sander.

1. 
   1woodmaster | Feb 22, 2009 03:01am | #3

   Hi Don,

   That's really interesting.  I havn't heard of it before.  I'm going to try it as soon as I get a chance to pick up some glycerin.  It's really kind of a neat concept.  The alcohol helps disolve the glycerin, the glue goes into solution with the water, and they all combine together to get your flattening solution.

   Glycerin is hygroscopic so it is continuously collecting water until it is saturated.  Through research, I found that if you leave a bottle of glycerin open in a room it will eventually absorb water until it is saturated.  At this point it is about 20% water and 80% glycerin. 

   It seems that what is happening with the flattening solution is that moisture is making the veneer plyable so that it can be forced flat.  The glycerin is added to draw in as much of the glue/water mixture as possible.  Once the veneer has had time to absorb as much of the glue/water mixture as possible, it is dried and the glue actually holds the veneer flat.  It works as stiffening agent.  I guess it's a pretty cool idea.

   Have you experienced any problems with the veneer not accepting stain with it being saturated with pva glue?  I'm going to keep this one in the files.  There may be an application that I can use it on in the future.  Thanks for sharing.

3. 
   tom77 | Feb 22, 2009 05:46am | #4

   Neil,

   There is a product called GF-20 from Veneer Systems, Inc. It is used to soften and flatten veneer. It contains the materials listed in the post about home brew softener, but the proportions listed don't sound right. I have used GF-20 and it works well. The process is very similar to the process listed in another post. Spray both sides of the veneer and let it soak in. Then place it between two flat boards with some absorbent paper next to the veneer. You will need to clamp the boards to flatten the veneer, but be careful not to crack the veneer. You may have to do it in stages. Change the paper in 30 minutes, again in an hour, again in 2 hours, and again in a few more hours. You can also use mdf without the paper, as it absorbs the moisture readily. You will need multiple pieces of mdf. (use both sides) You can usually tell when the veneer is dry, as it will feel cool when there is still moisture in it.

   This should give you another option. Good luck, Tom.

1. 
   Ron01960 | Feb 22, 2009 05:41pm | #5

   I use the same formula as Don, and have for approximately 2 dozen assorted batches of veneers. Without a problem. I always use shellac in refinishing and have never observed a color contrast between flattened and non-flattened veneer from the same lot on the same piece.I hope this helps!Ron

4. 
   brad805 | Feb 23, 2009 05:05am | #6

   I have also used the home brew flattening solution, GF-20 and Joe's version.  I have found the GF20 works the best and since there is no adhesive is a little easier to work with.  The GF20 will not keep the stock as flat as long, so timing is important.  What type of veneer are we talking?  A crotch, burl or just some wrinkly exotics?  I dont think the hanging solution will work all that great since many times the wrinkly stuff is quite brittle.  The glycerin is important since it softens the fibers and allows you to cut the veneer.

   Darryl Kiel's DVD is a great reference for flattening veneers.

   Brad