Gluing primers

[Fred W. Hargis Jr]

Are we talking about the same thing? I've never heard that before. The problem I have is the glue ridges that appear on the seams after the wood moves a little. Does salt solve that?

 

 

PS, I did some searching on this and did come across this: (it was on the Wood site when someone asked about using salt to stop joint slip)

"Leave the salt in the kitchen, Herm. According to Jeff Loflin, glue specialist at Franklin International (maker of Titebond wood glues), salt (and sugar, too, by the way) can react with wood glue and alter its composition, resulting in a weakened joint."

Edited October 8, 2019 by Fred W. Hargis Jr

[FlGatorwood]

I meant to add this link last night but SWMBO had other objectives.  

 

https://www.familyhandyman.com/woodworking/woodworking-tips/thinning-glue/

 

 

[Gene Howe]

6 hours ago, Fred W. Hargis Jr said:

Are we talking about the same thing? I've never heard that before. The problem I have is the glue ridges that appear on the seams after the wood moves a little. Does salt solve that?

 

 

PS, I did some searching on this and did come across this: (it was on the Wood site when someone asked about using salt to stop joint slip)

"Leave the salt in the kitchen, Herm. According to Jeff Loflin, glue specialist at Franklin International (maker of Titebond wood glues), salt (and sugar, too, by the way) can react with wood glue and alter its composition, resulting in a weakened joint."

To be honest Fred, I've only tried it one time on some 8' long 5/8" thick pieces. It helped keep them aligned. It was a rifle case so, not much stress on the joints. In 32' of glue line, I might have used a 14 tsp or less of salt. I used one of those small cardboard shakers you might take camping. 

I'm not surprised at Mr. Loflin's response. CYA, ya know.

I get squeeze out every time. I just let them gel and scrape them off with a plastic Bondo applicator. 

 

[Fred W. Hargis Jr]

No doubt his comment was a CYA.....but it sounds like we were talking about 2 different circumstances.

[Gene Howe]

I'm confused, then. But, what else is new?

 

[Fred W. Hargis Jr]

"Glue creep", by my definition is the slight raised ridge you get along glue seems on an otherwise smooth surface. It's caused by (according to some, there are various explanations) the wood moving, and the glue doesn't. When the wood retracts, it eaves a slight ridge that can be felt, or sometimes even seen.....and is really annoying. For whatever reason, the UF glues don't "creep", so I use them in all table tops. My guess is you were using salt to stop the joined boards from sliding out of position when being clamped. Did I get that right? Maybe if someone has a different take on this, they''ll correct me.

Edited October 9, 2019 by Fred W. Hargis Jr

[Gene Howe]

Aha. I FINALLY understand...I think. Yeah, I was thinking of the misalignment that sometimes happens. So, is it that the moisture in the TB causes the wood to swell at the seam and, when it dries you get the glue ridge? Whereas, the UF lacks that moisture?

I've not experienced that problem. Maybe because it's so dry out here. 

 

[Fred W. Hargis Jr]

I've read a ton of stuff about glue creep and I'm not sure what causes it. I've read several explanations and all seemed credible. I just know it sometimes happens with PVA glues, and doesn't happen with (at all, IME) with plastic resin glues.

[Gerald]

The basis of the theory that the water in the glue causes the wood to swell at the joint is based on how quickly you remove the squeeze out. If you simply let the glue dry and then smooth the joint you can then get a depression at the glue line because you have also removed the wood that had swelled . Not actually creep but a result related to it.