Fastening picture frame miters together

[JohnR]

[Sam Schmenk]

Wanted to add a suggestion I learned from FWW. Create a glue wash: half glue/half water. Apply to joints and do not assemble. Let dry to touch for 1/2 hr or so. Then glue and clamp as usual. I made a scratch frame to test for strength. WOW, very strong. Convinced me. The wash deepens the glue penetration and the drying time keeps the end grain from starving the joint. I also personally believe the slight rising of the grain of the wash allows some play when clamped to hide minor imperfections. SS

[Mike Marlow]

I like this idea - in theory. Seems like it ought to really work and stand as an improvement over just gluing the joint - but that's based on applying logic and principles from similar types of operations. This is one I'm going to try in the near future. First I have to get this '52 Dodge out of my garage so I can turn the woodshop bay back into a woodshop...

[George]

Well, don't like the theory - it's wrong. The thinned glue mixture is used as a sizing to _lessen_ the "penetration" of the glue, which is what starves the joint. Like the practice, because it works, of course, but is no substitute for a mechanical aid.

[Sam Schmenk]

My explanation or "theory" was an educated guess, there was no scientific method at work here. All I know is that it works for me. My frame "production" has been limited to milled up beefy shaker/craftsman style frames, so smaller stock where the glue surface area is minimal prolly will need mechanical aid. For reference, the technique was in FWW article on mitres a few months back by Gary Rogowski sp? I'll dig out specifics if some guys want it. BTW, I built the mitre sled in the article and have been mostly successful with it. SS

[George]

Good technique, old as glue, but the theory, as I'm sure you'll find, is incorrect. The end grain starves the joint because the glue is wicked in. The sizing keeps it from wicking in.

The mechanical fastener protects even a delicate frame from opening up if the brittle glue line is broken. Which is why you'd rather brad the corners while the glue is flexible. Doesn't even take a blow to do it, as you'll find if you research the miter joint. Movement of the wood with moisture changes can do it as well. Which is reason enough to insert a brad for shear strength in the load direction, or fasten the entire miter either decoratively or, with a monster frame, with gross-looking but hidden plates or gussets.

[oldsalt]

John: check out the following links. A lot of negative/popsitive comments have been posted regarding HF products, I have been a customer for many years and have rarely had problems with any of my purchases. Having a local store makes it easy to return any items I had problems with, I have never had any negative responses when I returned an item for replacement.

?itemnumber=46836Good Luck

Jamie