Glue Choice for Laminating Cedar

Polyurethane adhesives are reported to work well for exterior laminated cedar glue-ups. March 4, 2006

Question
We have a project coming up that will require some unusual sizes in western red cedar: 3x5x9' posts and some cantilevered "s" shaped pieces that will need to be bandsawn from 2x10s. The specs are for clear cedar throughout. As we can't find anything clear that can be cut to 3x5, and I have some concerns about the stability of the "s" curves, I'm wondering if anyone has experience and success laminating cedar. I'm thinking epoxy as a possibility.

Forum Responses
(Architectural Woodworking Forum)
From contributor M:
I am working with that same material now. I am making outside arch windows. I am using Titebond III, which seems to be working. Also, you might want to call Liberty Cedar in West Kingston. I was just there and they have all the sizes you need. I even saw 6x6x14' stock there.



From contributor J:
I've had great success using polyurethane glue (Excel). I did an exterior curved railing top with cedar strips (3/4") 8" wide. After 8 years, still looks great. You can't go wrong using this.


From contributor B:
Years ago, I did some testing with Titebond and Titebond II on cedar. Both failed and I was advised by Franklin Adhesives to wash the surfaces with acetone prior to glue up. The acetone test also failed. Since then, I've used polyurethane glue on cedar and had no failures. When Titebond 3 came out, I did a test with that and the joint held as the wood split apart. So TB3 is probably a good alternative. However, I will stay with the polyurethane. We do cedar jamb laminations with it on a regular basis.


From contributor J:
I should have added to my previous post that you need to check moisture content of wood when using poly glue. If above 15%, then glue only; if below, you need to dampen at least one surface with water. Glue lines are not a problem if strips of wood are prepared and clamped properly. Another good thing about polyurethane is it's a gap filler.


From contributor B:
You bring up some good points. I will add that with regard to gap filling, polyurethane will indeed fill gaps. However, there is no strength in that area the way there is with epoxy.