Plastic Resin Glue -- Alternative to Weldwood?

[Izzy Charo]

Hi All,
I was looking for some Weldwood PRG to glue up a bent lamination, and discovered that it is basically unavailable. Has anyone found an alternative plastic resin glue? My understanding is the yellow/white water based glues don't harden as well as PRG...Or perhaps the better question is what have folks used to glue up bent laminations that has worked well?
Thanks!
Izzy Charo

[Dennis Jarchow]

I use Unibond 800 for all my veneer work including curved laminations. Very rigid and very little creep.

[John TenEyck]

PRG is no longer manufactured. I switched to Unibond 800, but there are other UF glues available with essentially the same characteristics. FWIW, you can adjust the cure time of Unibond 800 by changing the mix ratio of catalyst to resin, it doesn't require high clamping pressure, it cures faster, and it cleans up easier than PRG. The only downside is it costs more, but that's a hollow argument since PRG is no longer available.

John

[Kevin Jenness]

Here's one option https://veneersystems.com/product/urea-plastic-powder-resin-ppr-5-gallon/

Also https://www.veneersupplies.com/products/Ultra-CAT-PPR-Veneer-Glue.html

Unibond has less water than ppr, an adjustable cure time and costs more

[Mark e Kessler]

I am actually doing an unscientific experiment with t2, t2 extend and t3. I just squirted some of each out, let it dry for a week or so and found that t3 was definitely more stiff than the others.

I have used t2 for 25yrs on raw veneer with no issues even bent laminations (with some spring back) and on shop sawn veneer when the edges are captured in a frame. I will be using t3 for raw veneer from now on and since i am 25 yrs older now and more risk adverse will ise unibond 800 or proglue which is a urea glue but with low formaldehyde.

There are also pva’s with higher solid content that claim to be more rigid but I read somewhere that higher solid content may affect bonding so who knows

[David Zaret]

unibond 800 for me. i like that there are different colors for the hardener, that i can thicken the glue to fit the particular application, and that it accepts transtint to dial in a dark color as needed.

[Kevin Jenness]

I am actually doing an unscientific experiment with t2, t2 extend and t3. I just squirted some of each out, let it dry for a week or so and found that t3 was definitely more stiff than the others.

I have used t2 for 25yrs on raw veneer with no issues even bent laminations (with some spring back) and on shop sawn veneer when the edges are captured in a frame. I will be using t3 for raw veneer from now on and since i am 25 yrs older now and more risk adverse will ise unibond 800 or proglue which is a urea glue but with low formaldehyde.

There are also pva’s with higher solid content that claim to be more rigid but I read somewhere that higher solid content may affect bonding so who knows

Interesting, and contrary to my own experience. Titebond 3 dries to the gummiest state of any Titebond product I have used (Original, Extend, Titebond 2 and T2 Extend). That plus its very poor heat resistance http://www.titebond.com/product/glues/e8d40b45-0ab3-49f7-8a9c-b53970f736af has lead me to steer clear of T3. Maybe they have changed the formulation since I tried it.

Titebond Extend cures to the most rigid glueline in the Titebond family, and they tout it as "ideal for complex assemblies and bent laminations". http://www.titebond.com/product/glues/d7c6f86b-93cc-4400-99ed-79f8a75a2e95 I use it for most veneer work that doesn't require moisture resistance or extended working time.

[Mark e Kessler]

Interesting, and contrary to my own experience. Titebond 3 dries to the gummiest state of any Titebond product I have used (Original, Extend, Titebond 2 and T2 Extend). That plus its very poor heat resistance http://www.titebond.com/product/glues/e8d40b45-0ab3-49f7-8a9c-b53970f736af has lead me to steer clear of T3. Maybe they have changed the formulation since I tried it.

Titebond Extend cures to the most rigid glueline in the Titebond family, and they tout it as "ideal for complex assemblies and bent laminations". http://www.titebond.com/product/glues/d7c6f86b-93cc-4400-99ed-79f8a75a2e95 I use it for most veneer work that doesn't require moisture resistance or extended working time.


So funny, you just posted this, i went back to my samples to confirm and I don’t know how i got mixed up but you are correct. The t2 is super flexible, the t3 is definitely more stiff but will completely bend over without breaking and the t2 extend bends but does yield and snaps.

One other thing I found that is maybe known is if the glue sits for awhile (don’t know how long) you definitely need to mix It, I hadn’t used the t2 extend or t3 in awhile and it was definitely softer more flexible then after mixed up. When i did the first test the t2 extend was softer than I remembered which I thought was weird so i mixed it up and it was stiffer more “snappy”


Hard to convey in a pic but here it is, I also made a video but not sure if you can post here, never seen one. I will probably post it on my IG
473578
473579

[Kevin Jenness]

T2 Extend has solids that settle out like Cold Press. Titebond Extend (non-water resistant) is what I keep on the shelf along with T2 which gives a faster tack and decent water resistance.

I don't keep UF adhesives on hand because of their short shelf life. (Unibond 800 can be kept for longer if refrigerated. That may be true for ppr as well.)If I need a UF glue I will order in some Unibond or ppr, but rarely. They are good where a very stiff bond with limited bleed-through is wanted like laying crotch or burl veneer. I used to find Weldwood on local shelves, but unfortunately no longer.

Epoxy has a virtually unlimited shelf life so I stock that and use it for applications requiring extended working time, water resistance and reasonable stiffness. It does bleed through veneer, but you can embrace that and use it as a sealer on the face.