Biscuit joiner question

[JohnnyC]

I have a weird situation with an window extension jamb. The extension jamb is a pre-built frame that goes all the way around the window. I cannot remove the extension jamb frame, but I want to install a stool piece to the jamb. ( I am upgrading the casing etc) My thought was using biscuits to join a bullnose piece to the jamb. The bullnose is about 1 1/2 inches wide.

The problem...I cannot lower the fence of the joiner all the way due to the jamb width (about 2 1/2 inches). What is the technique to ensure the biscuit cuts will line up between the jamb cut and the stool cut? Also, if this is the wrong way to attach the bullnose, please let me know.

Thanks for your time.

[Zz Yzx]

I can't answer your question, but you might try alt.home.repair. They're a knowledgeable group.

-Zz

[woodstuff]

Maybe use dowel pins?

woodstuff

[Swingman]

That'll work, if I understand you correctly.

Don't use the fence of the plate joiner at all.

You will probably have to use the jointer upside down to do this, but that's not a problem.

Hold/clamp a board wide enough to sit on top of the stool and extend beyond the front edge; use that as an "upside down" reference surface (a helper can exert enough downward force if you can't use clamps), it doesn't take much.

With your plate jointer upside down, cut your biscuit slots in the existing stool, using the extended reference surface as the base (upside down) for your plate jointer.

With your new bullnose piece right side up, hold it to the stool and mark the center of the slot locations already cut.

On another level surface as a reference surface (bench top?), flip the bullnose piece *upside down* and cut your slots on the marks, without using the fence.

Flip the bullnose piece right side up ... it should now match for alignment purposes. Hopefully you can put some clamping pressure for the glue-up by opening the window and clamping across the stool.

[JohnnyC]

Thank you, Swingman. Your explanation was excellent.