Choosing Glue for an RF Edge Gluer

Selecting suitable adhesives for fast application and curing. May 4, 2005

We recently purchased an L&L RF edge gluer. Does anyone know what kind of glue we should use for gluing pine panels? I've heard you have to use some kind of additive to mix in the glue specifically for an RF unit.

Forum Responses
(Adhesives Forum)
From Jeff Pitcher, forum technical advisor:
RF gluing equipment essentially heats the glue line in order to speed up the cure. Most adhesives intended to cure under heat will work fine. The two most commonly used adhesives are urea resin glues and cross-linking PVAs such as Titebond II or MPA II.

From the original questioner:
Thank you for your reply. We've tried Durolock from National Starch and they actually sold us some kind of hardener with it, so we mix it with the glue itself in some proportion. The problem is that it doesn't glue fast enough, not according to the L&L's specs, anyway. And we have a brand new RF tube so the power is certainly not the problem.

We've also been advised that in order to speed up the process we must use some kind of catalyst. Should I mix that into the glue or it is some kind of myth? Also it would be nice to know how much glue we should use for MBF of panels. We currently glue 2"X6/4" pieces into panels.

From Jeff Pitcher, forum technical advisor:
Durolock should work fine. Depending on the number, you shouldn't need to add additional catalyst. There are many cross linking PVAs that already have the catalyst in them. The biggest drawback to using this kind of glue is that you have to wait for it to cool before you can handle the piece being glued. A UF resin will give you a rock solid bond almost immediately. That might give you the additional speed you're looking for. A good rule of thumb for calculating glue spread is to figure 30-35 lbs per thousand square feet of glue line. This translates to about 300-350 square feet of glue line per gallon.

From the original questioner:
Thank you! Could you suggest any good UF resin glue for both regular and water resistant panels?

From contributor K:
I have an L&L GlueAll and have always used Titebond II with no problem. It's available everywhere and can be used all over the shop. We glue hardwood panels for doors (usually ash and oak) around 180 seconds, pullout and saw to size, then surface and raise. Sometimes the panels are still warm when we are raising them. Never any problems except with pine.