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Phil Winn
05-14-2006, 3:01 PM
For the Tressel/Trestle table I am making, I am using M & T joints--
I am worried about glue space---
1. How tight should the joints be, not to starve the joint of glue;
the glueing surfaces--4 sides around the tenon and the end grain
surface??? The joints are snug...
2. Glue to use--Tite-Bond 3, or Polyurethane glue?
3. Any suggestions on how to apply the glue?
Thanks,
Phil

Rich Fishel
05-14-2006, 4:26 PM
Not that I'm an expert on MT, but I apply the glue to all sides of the tenon and the end grain, and also on all sides of the mortise, all applied thinly and evenly with a paintbrush. If you are glueing multiple tenons across a solid table top, glue the center tenon as above, but lightly glue the end tenons to allow for movement. I use TB III, but I'm sure everyone has their favorites.

Mike Wenzloff
05-14-2006, 4:33 PM
Hi Phil,

The joint is an interference fit--it should be what I call pleasantly snug. I shoot for a joint I can push together but has no slop. The instant glue hit, the wood will begin to swell.

I do not put glue on the end of the tenon shoulders. Nothing to be gained as far as strength goes, and just one more area to clean squeeze-out. In fact, I apply glue usually only on the mortise walls. If I apply any to the tenon, I usually use a thinned version mostly as a glue size.

I usually use white glue vs TBIII. More open time and no need for the water proofing. I do use TBII sometimes, but never on large assemblies. More often than not I use hide glue. High tack, long open time.

I use a stiff brush of some sort for application [generally]. For hide glue, a good one I reuse. For anything else, a disposable one.

I usually glue up sub assemblies whenever possible. As I get older I move slower.

Take care, Mike

Kirk (KC) Constable
05-14-2006, 5:31 PM
If it's a 'closed' mortise and tenon, I use Gorilla glue in the mortise and just a 'scrubbing' of it on the tenon (so as to not use too much). On a properly fitting mortise and tenon, I've found it very nearly IMPOSSIBLE to 'undo' a MT in the glueup process when using PVA. The Gorilla (and all polys) is 'slicker' and you can still work with it a few minutes to correct a problem if you need to. I often do. :o

KC