Recently I had a rather bad experience with the residual glue from veneer tape. I used the water based glue kind with a vacuum press. Removal was by wetting and scraping….no problem. There was no residue to be seen on the surface UNTIL we stained using a water dye. Then, wherever the tape was, the dye wasn’t. After much scraping, sanding, and wiping, the job was complete. The frustrating thing about it all was the glue residue could not be seen prior to dying. Four experienced people checked the surface and couldn’t see the residue. The wood is both figured and quarter sawn ash. Does anyone have a foolproof method of removing the glue residue? Any tricks?
I’ve searched this site and this subject has been covered before, but I’m hoping someone can offer advice that is new. Past comments have dealt with wetting and scraping only. Thanks for any help. There’s more veneering to do on this job and I really don’t want to go up the wall again!
Replies
Make up a wee test board tomorrow using your existing methods, up to and including the wetting, scraping, sanding etc., to get the same result prior to experiencing your staining (or dying?)problems. Then, before dying or staining get some hide glue and thin it out, about 8% to 10% hide glue, and the rest of water. Dip a rag into this mush, squeeze it out a bit, and do a glue wash by wiping all over to get the veneer nicely wet, but not soaking. Let it dry thoroughly, sand to knock back the raised grain, and try your dying/staining again. I tend to use hot hide glue for veneering, and for this trick.
This may, or may not work, but it's worth a go in a sample. It's a typical procedure for me. If your original glue was PVA, make a similar wash of PVA. If it was urea formaldehide, make a wash of this stuff, etc.. If you glued down with epoxy, er--- well--- I'm not sure of a suggestion, ha, ha. Slainte.
Thanks for the response, but I am thinking you misunderstand my problem. It is the glue from the veneer tape specifically that fouled me up, not the veneer to substrate glue (which was urea resin, Unibond). Actually I did experiment with a glue wash seal coat on this veneer, a curly ash. The purpose was for the control of the dye but it didn't help and I felt would be far too unpredictable over a large surface area.
Your suggestion seems to be a response to veneer to substrate glue bleed-through. Is that right? If not, I guess that I fail to comprehend how the glue wash will help.
Maybe I should have veneered with epoxy, then I could have sandblasted the whole bloody thing to remove the tape and glue residue. Better yet, do you have a source for curly ash plastic laminate?
Hi Jeff,
I use masking tape. Just peel it off carefully after the glue has dried. And I don't run the tape along the whole seam, just across every three or so inches.
Don Kondra - Furniture Designer/Maker
jeff, I didn't misunderstand your problem, realising it was the gum from the tape you were concerned with. I seldom have the problems you outlined. I usually manage to remove the tape and glue successfully-- my normal method is to dampen the tape for quite a long while, no hurrying at all and I peel it off in one long continuous strip. Then more water and patience to tear off the original short cross join pieces, and a bit of wiping with clean water to remove all the last of the gum. I wondered if you'd been hurrying the paper and removal, for that's the only time I've had trouble. My plan with the wash was in an effort to dilute and spread any tape residue over the whole.
I find Don Kondra's masking tape suggestion interesting. I've only used this once, and the failures that resulted from its use has caused me to never use it again. The failures were that the tape imprinted into the veneer leaving a severe dent, and the glue adhered so strongly that it tore out the veneer grain badly-- right down to the ground in places. I used it in a heated bag press, and I suspect that this was the primary cause of the problem . Slainte.Some stuff I've made.
OK, now I understand about the wash. You may be correct in guessing that I hurried the process. I let the water soak only long enough to easily strip the tape, but probably not long enough to thoroughly wet the glue that was really stuck to the surface. Daryl at Vacu-Press also has advised to wet and wipe more. He suggested the use of a scrubby sponge to scour the surface clean. I will be more diligent in the future.
I have considered masking tape as Don uses. However, I find that the vacuum bag press can really make masking tape, even the blue stuff, stick tight.
Thanks for the advise. I'd send you a homebrew (I make English ales) but .... boy howdy, what if it broke in transit? That would be a shame. So, I'll simply have to drink one for you!
Having had the same problems with veneer tape I tied masking tape a while back. I experimented with a couple of different brands of low tack masking and found that price = performance. With the real expensive stuff doing a great job. I figure it may cost a little more up front, but if it saves me an hour of cleanup everytime I veneer, then it more than pays for itself!
Morning,
Sorry for not being more precise. The tape I use comes from a cheque printing company and is specially formulated to not tear paper. The normal masking tape indeed does pull the wood fibres.
And, yes it does leave a "dent" in the wood but normal sanding removes it. In some cases I wet the spot and touch it with a hot iron, puffs it right back up....
But of course the main advantage is the tape sticks immediately and is easy to remove...
Don Kondra - Furniture Designer/Maker
I use painters masking tape - a low tack tape I buy at the paint store. I veneer cold so it doesn't bond. I never have problems with the thickness of the tape, but I only use thick bandsawn veneers - usually from the firewood pile. I've had similar problems with veneer tape and other water softened tapes - they all leave a residue. If I find a residue (by wetting lightly and looking quickly for light spots), I place a wet paper towel over the area for just a few minutes and then scrape.
I'm really sick of using oak cauls and 100 lbs of clamps, so I'm going to get a bag system as soon as I can find a used vacuum pump and some vinyl sheet. Anyone make their own bag? How'd you do it? (Did it work?)
Jeff,
Here is a little trick I learned from another woodworker that works much more commercial veneer than me. First joint the veneer so you have a nice tight fit then tape the pieces together like you would with veneer tape but instead use normal masking tape. The fold the two pieces together and run a small bead of glue down the seam. Then reopen the pieces and lay them on a flat surface and use a j roller to work the seam flat. In half an hour you can remove the tape and press the pieces as a single sheet. Of course this method is intended to be used on smaller pieces like door panels and such. I don't think it's practical for a burst or something along those lines but it work's well and you don't have to worry about any tape glue on you finished panel.
I've done the pre-glue thing before, but using the j roller is a good tip. In this past case, my largest panel was 5 by 9 feet. I'm still not sure that pregluing wouldn't be a bad idea, but that seems awfully big to have to flip and fold a lot.
Thanks for the help.
I sometimes have the same problem. The glue basically soaks down into the grain of the veneer, and it is hard to get out. To prevent the wood from absorbing the glue so much, I don't get the veneer tape real wet when applying it; I just run it over a damp sponge. If it gets too wet, I stick it to my bench to remove some of the glue before I tape up the veneer. When I remove the tape, I remove as much as I can with a card scraper before I apply any water. If you apply water, and allow it to dry, the wood will soak up the glue, so by removing as much tape beforehand, there is less glue there to absorb. I will also only wet down the tape that I will immediately remove, so the glue doesn't have the chance to soak into the wood.
To see is there is any glue left on the surface, try wetting the area around the glue line and holding it up to the light. You can usually see a change around where there is still glue.
Tom
Thanks to you and all others who have helped. I've been trying everything. The one method I've ruled out for sure is using masking tape under pressure. It really sticks and inevitabely leaves some glue residue. This cleans up with naptha, but I think I'd rather breath water fumes than naptha.
You might try 3M's paper tape, usually used for labeling or hinging. It's VERY low residue, but the tape itself is pretty thick. It would probably indent the veneer in a vacuum bag but it sure won't leave any glue behind.--
Lee in Cave Junction, Oregon
On the Redwood Highway
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