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View Full Version : Glue for Vacuum Press Veneer?



Tenson
02-09-2014, 05:17 PM
Hi guys,

I need to veneer some flat birch plywood panels with various species of veneer. I tried with PVA and then putting in the vac bag but it didn't glue very strongly at all. I left it in there for about 24 hours then took it out to cure for another 12 hours. It peeled off easily.

Can anyone recommend a glue that will work in the vac press? Hopefully one that is not super expensive. I've looked at Cascamite, Aerolite 306 and Extraphen.

Cascamite is strong and affordable but it is a powder mixed with water so I think it still relies on evaporation to set. Aerolite is also mixed with water to apply but has a separate hardener that is put on the other surface so I think it might set quickly even in a vacuum then I can take it out to cure once fixed. Extraphen looks super strong and is a 100% chemical reaction adhesive but damn it's pricey!

EddyCurrent
02-09-2014, 05:51 PM
There's only one glue I use now and that's Titebond Original

There's a tip about vacuum press use about halfway down this page.
http://www.titebond.com/application_tips.aspx

Also this but I've not tried any of it.
http://www.airpress.co.uk/99-adhesive-for-veneering-and-laminating/

mekanik
02-09-2014, 10:20 PM
Hi Tenson
I have used some glue i purchased from a guy on ebay and it has been fine for a few jobs i have done, one was a internal window sill, 3mm Iroko veneer onto a laminated softwood base this is holding up fine and Iroko is very oilly so I was quit impressed13263
Will check my records for the trader if your interested

mekanik
03-09-2014, 09:10 AM
Morning Tenson, this is the stuff.
http://www.ebay.co.uk/itm/502-ALL-PURPOSE-WEATHERPROOF-WOOD-ADHESIVE-GLUE-EVERBUILD-500ML-1LT-5LTR-/181328687963?pt=UK_Crafts_Cardmaking_Scrapbooking_ Glue_Tape_EH&var=&hash=item2a3808335b
Just out of interest did you have a breather mesh over the veneer ?13265

Tenson
03-09-2014, 02:18 PM
Hi,

I just had a piece of MDF on top of the veneer to help press it down and absorb some moisture but obviously it didn't do a lot.

What is a breather mesh? You mean like some kitchen towel or more like a wire mesh?

Isn't that glue just PVA?

EddyCurrent
03-09-2014, 03:39 PM
If you'd just followed my link to the airpress website there's everything you need to know :hopelessness:

Tenson
03-09-2014, 04:01 PM
If you'd just followed my link to the airpress website there's everything you need to know :hopelessness:

I did follow your links. The first one says put some wood in with it to absorb moisture. The second link has a PVA glue and a urea-formaldehyde glue. Both are water based so still need some evaporation to set.

The glue Mekanik linked to is a PVA like the 'EasyBond D3' in the Airpress website. I don't see how this is going to be any different than the PVA I already tried (Polyten).

I've ordered some powdered urea-formaldehyde glue. I think this breather mesh sounds like a good idea to provide a bit more air for the glue to set. I also wonder if some of those silica-gel packs would help.

EddyCurrent
03-09-2014, 05:44 PM
Yes, but not only that it tells you all about how to do the job with a breather mat etc.

mekanik
03-09-2014, 05:48 PM
Hi Tenson
If you look @ my setup you will see that the veneers are covered in a blue material, this is a plastic mesh that i use for doing vacuum infusion jobs, if you go to any online dealer that sells infusion resin you will find some there, the white tubing is spiral wrap. cheapest place to get this is Maplin(or it was when i bought mine) it's used for holding loose wires to tidy them up.
If you notice you will see the glue extruded through the joints between the veneers. This was a trial run to see if i could make a half decent job of it as i intend to do all my sills the same (the windows are Iroko also)
Hope that helps and good luck with your next shot.
Mike

mekanik
03-09-2014, 06:11 PM
This is what i used
http://www.ecfibreglasssupplies.co.uk/p-1885-vi1-knitted-infusion-mesh-1m-wide.aspx

Tenson
03-09-2014, 06:18 PM
So you are putting the breather mesh on the veneer side?

mekanik
03-09-2014, 08:32 PM
Yes, the veneer is then subject to full Atmospheric pressure.

Ger21
03-09-2014, 10:17 PM
Any PVA glue should work fine. I'm guessing that you either didn't use enough, glue, you didn't get it in the bag fast enough, or you didn't have enough pressure.

I generally use Titebond Cold Press veneer glue, as it gives a little longer working time. I only leave it in the bag for 90 minutes, and never use breather mesh. I always use a hard caul over the veneer, though.

I've also had good results with plastic resin glue, which comes in powder form and is mixed with water.

Tenson
05-09-2014, 01:10 PM
I've got some powdered urea-formaldehyde glue now (Resintite, aka Cascamite, Extramite) and done a few test glueings and it seems good to me. It needs very little water added to the mix and sets good and solid more like one would expect of a resin than PVA does (PVA is also a resin).

I've also got some fine wire mesh so I'll try putting that on top of the veneer and then some tissue paper on top of that to help absorb moisture.

One more question - what do you guys do for bags? AirPress bags are really expensive and I've tried those vacuum bags for putting duvets / clothes in storage and although they work, the plastic is very soft so it easily gets small holes from any sharp edges. Yes I know I need to tape over the edges etc.. but it till happens.

Ger21
05-09-2014, 01:40 PM
I made my own bag from sheet vinyl. See www.joewoodworker.com for examples.
Check marine supply shops for vinyl sheet, as it's used for windows in boat covers.

After a while, I got tired of slidin in and out of the bag, so I built a frame press using polyurethane sheet. Much easier than using a bag.

Tenson
05-09-2014, 02:01 PM
Thanks! I had no idea 'vinyl cement' existed :)

mekanik
05-09-2014, 03:42 PM
Yea I do the same as Gerry(sort of) i had some polythene sheet left over from my UFH job so used that, nothing fancy folded it in half and sealed the other edges with tape, get a waterproof grade as not sure if some tapes are air permiable.
Should be able to see it in the photo.If you doing a lot of veneering then go for a set up like Gerry's.
Mike