Stains and glue

[Bob Willson]

Why do all the books that I read insist that the joints should be taped before staining? I would have thought that it really didn't matter if the tenon or whatever was stained the same colour as the rest of the timber.

I am using a Wattyl Tradesman stain that is alcohol based (as opposed to water based). The pigment in the stain surely would not stop the glue from adhering properly, so as long as the stain is allowed to dry out thoroughly there should not be any problems. Or am I missing something? :confused:

[soundman]

you are missing something.

The issue is that stain will cont consistantly work over the glue.

so you tape the joint to prevent the glue marking the adjacent timber. Thus the stain will work consistantly right up to the joint.


cheers

[Bob Willson]

I am currently trying a test to see what sort of difference it makes. I have stained two pieces of maple with the Wattyl stain and allowed them to dry. I have then glued the two pieces together and clamped them. Later today I will try to rip them apart.

[Bob Willson]

Ok
The glue was allowed to cure for 24 hours then I smacked it on one end of the test piece with a mallet. The attached photo shows what happened. The timber gave way rather than the glued joint.

Still, overall I'd be inclined to go with soundmans advice that the glue would not give as consistent results when applied over stain.

Ah, just re-read soundman and what he was saying is not what I read him as saying. :) I am actually finishing the staining etc BEFORE assembling the pieces and BEFORE adding any glue into the problem. The reason for this is that whenever I have managed to leave a little bit of glue behind on the surface of the work the stain reacts differently and generally gives a nasty streak of darker stain. You can't see this until you apply the finish and by then it is too late

[soundman]

I could be considered smart to stain before assembly in many situations unless.

you are grain filling and or doing other surface treatments that could effect the penetration of the glue prior to staining.

If the stain is a a dye type stain It should not in its self effect the gluing performance at all. However if the carrier is oily (turps) or has othe solids or chemicals in it there could be a posible problem.

One thing I have learned to do is do as much surface preparation as early in the process as possible, providing it does not cause later problems or be damaged by handling.

cheers