Replies

1. 
   brad805 | Jul 22, 2008 11:38pm | #1

   Some questions:

   1.  What type of vacuum press?  I assume the press was reaching vacuum and it was not cycling due to a leak in the system somewhere.  Does your platten have air slots in both directions to allow the vacuum to extract all the air.

   2.  Did you roll the adhesive smooth so the veneer bonds properly? 

   3.  Was the birdseye maple flat when it arrived?  I suspect it was, but thought I would ask.  I am currently working with some Markore and Bubinga Swirl crotch woods that I have to flatten before attempting to press or cut.

   4.  Any chance of seeing a picture before or after so all can understand how wrinkled it is?

   Brad

1. 
   130Mike | Jul 28, 2008 03:49pm | #17

   Vacuumpress had good pressure and was not cycling

   adhesive was smooth and roled on sufficiently

   veneer was flat

   platten thad air hole however I did discove I had it in backwards (air hole in platten away fro exhaust valve.

   Switched to urea formaldehyde glue with better luck but still some rippling.

   will try to get some pictures tonight and post them

   Thanks

1. 
   brad805 | Jul 28, 2008 09:01pm | #18

   From your description of your platten it is not clear to me if you grooved the platten at approx 6 - 12" on center in both directions and the grooves are up in the bag to allow proper air flow?  If not, it will not work properly.  My first attempts at veneering some time ago went off without a hitch largely due to having great info from a DVD.  If you do not have any DVD's I would highly recommend one such as Darryl Kiels

   Ciao

1. 
   130Mike | Jul 28, 2008 09:09pm | #19

   Thanks...I will try the DVD.  My platten is grooved on both side and in both directions.  I think my problem may have been that I had ikt in backwards (i.e. the vent holes in one sie and one edge were away from the outflow valve and may have been blocked by the bag itself.  Am going to give it another try tonight

2. 
   MBerger | Jul 22, 2008 11:47pm | #2

   My first guess is that the bag didn't have enough clamping pressure, and the veneer didn't have enough pressure pressing it down.

   My second guess has to do with the glue application. I've experienced a similar result because I applied the glue inconsistently (thin on some areas and thick pools on others). Here's what happened: The veneer soaked up the moisture from the big pools of glue and expanded and bubbled in those areas. Meanwhile, the areas around the bubbles had a thin layer of glue and dried quickly, thus causing  bubbles and wrinkles to get stuck that way.

   Both guesses could be wrong, however... 

    

    

1. 
   130Mike | Jul 23, 2008 04:28pm | #5

   Thanks for your thoughts. I think I had pleanty of pressure but your second idea is very possible.  I tried another test last night with more even glue and it worked much better

3. 
   sapwood | Jul 22, 2008 11:52pm | #3

   I'm guessing that you didn't have a platen on the surface of the veneer. Rather, you relied on the bag to press the veneer directly. If I'm right, then that's the problem. One must have a rigid platen to press the veneer smoothly/evenly.

1. 
   130Mike | Jul 23, 2008 04:24pm | #4

   Thanks for the feedback, but, I did have an MDF Caul on top and it still wrinkled. 

4. 
   mapleman | Jul 24, 2008 07:32am | #6

   Mike,

   Go to Home depot or Lowes and get a plastic throw away trowel in the tile dept. Something along the lines of a 1/32 groove. Apply glue and then trowel away the excess going horizontally and then vertically across the substrate. This will keep the glue very even, less will squeeze through to the surface, and it will not pool and produce wrinkles.

   When I veneer I place an MDF or birch plywood platen in the press, followed by a few sheets of wax paper (keeps the veneer from sticking to the platen if the glue squeezes out). Then the veneer (glue side up) followed by the substrate with glue applied. I find this works out the best for me. I'm sure everyone has their own little tricks.

   Good luck,

   Lee

1. 
   DonC | Jul 24, 2008 08:09am | #7

   Lee,

   Your advice about the throw away tile trowel with 1/32" notches is really an important tip. I concur with your good advice. This tehnique is so good for large surface areas.

   For smaller glue application I use a very thin and flexible stainless steel handled bladed "knife". This "knife" is kind of like a frosting cake spreading knife. Even if I forget to put in in water, I can just scrape off the fried glue with a utility knife.

   I still use the acid brushes when I have too.

1. 
   mapleman | Jul 24, 2008 02:42pm | #8

   Hi Don,

   Thanks. Since I started using the trowel, I have not had any wrinkles or glue failures on my glue ups. If I forget to clean the trowel, an overnight soaking in a little warm water frees the dried glue up.

   Lee

2. 
   130Mike | Jul 24, 2008 06:22pm | #9

   Thanks...sounds like a great idea.  I'll stop at home depot on the way home tonight

3. 
   brad805 | Jul 24, 2008 07:07pm | #10

   The 9" foam paint rollers work well too for large surfaces.  I picked that up from Darryl Kiel's (Vacupress) DVD.

   Brad

1. 
   chaim | Jul 25, 2008 02:20am | #11

   Wow, I recently also experienced the same phenomenon with some walnut veneer (expensive where I am!) and was stuped as to why it occurred.

   I didn't think it was uneven clamping pressure, but couldn't be sure. I do not have a vacuume clamp but used plywood and hardwood cauls on the plywood and still ended up with ripples!

   I did use a foam roller to apply the glue, but I applied it to the veneer also. Was this possibly my mistake?

   Thanks for  a great (and apt) thread!

   Chaim 

1. 
   mapleman | Jul 25, 2008 05:36am | #12

   Chaim,

   It's best to always apply the glue to the substrate. Sometimes the glue can make the veneer curl, other times you can get those annoying wrinkles. Once you glue up your first perfect panel in a veneer vacuum press, you won't go back.

   As for the glue roller: I find that you can still apply too much glue with the roller. It's hard to get exact, perfect coverage.  That's why I prefer the trowel. There are times when I have to cover a large area with glue that I would roll the glue on but then I always trowel off the excess. I rarely have glue squeeze out the face side, I never have wrinkles, and I never have delaminations or spots that don't take (like a bubble).

   And here is a tip to try:

   If you join your veneer pieces with the perforated tape (with the re-moistenable glue) try gluing the tape down into the joint. In other words, don't leave the tape on the outside (show) face to be scraped or sanded off later. Everything you read will tell you not to do this, it will show, etc. I don't seem to have problems - and I don't have tape to clean up when my panels come out of the press dry. Do a test and see for yourself.

   Lee

1. 
   brad805 | Jul 25, 2008 08:47am | #13

   Lee

   thks for sharing your tape tip with all.  I have not had any problems thus far with the roller, but the trowel makes sense.

   Do you know the components of the softening solutions on the market?  The flattening solution I found and have been using to flatten some tricky veneers is composed of glycerine, alcohol, glue and water.   After flattening following the recommendations I found it seems the veneer may still be tricky to work with and am curious about the softening solutions I found on some websites. 

   Brad

    

   Edited 7/25/2008 1:29 pm ET by brad805

2. 
   mapleman | Jul 25, 2008 08:59pm | #14

   Brad,

   So far I have only used glycerine and water. Adding glue and alcohol seems like trouble to me.

   I have heard good reports about the flattening solution on the Joe Woodworker site (http://www.veneersupplies.com) but have yet to try it.

   Good luck,

   Lee

3. 
   brad805 | Jul 25, 2008 09:12pm | #15

   Thks for the reply.  This solution was one I found from Vacupress DVD's.  It gluesizes and helps to keep the veneer flat for a longer period of time, but I still have some edges that will be difficult to tape.  It is easy to flatten, but it takes a bit of time to get the sheets dry to avoid problem.  I found a softenening solution on a professional supply website, but have not found any info about it yet.

   Brad

5. 
   keithflknr | Jul 26, 2008 10:20am | #16

   i agree with Brad Joewoodworker is the best site for veneering