Finger joints and glue

[Jeff]

I built a jig to make finger joints on my router table. I'm using a

1/2" router bit and spacing the fingers 1/2" apart. It worked well. Probably too well. I had to dry join the wood with a rubber mallet and a vise. The fit is extremely tight. I suspect it is way too tight to glue. It seems to me that I'd want a couple thousands of an inch gap between the fingers to accommodate the glue. What's a good way to accomplish this? Should I just sand the fingers before joining?

[dadiOH]

Adjust your jig.

[cselby]

Move the jig a hair closer to the bit.

Pete

[Jeff]

You mean move the pin a couple thousands of an inch closer to the bit? I'm not going to be able to move the pin with that type of precision, but I can prolly make the adjustment by shaving wood off the runner that guides the jig along the router table. The jig straddles the table and I have a runner on each side.

Jeff

[Toller]

I use extended set glue on overly tight joints. It is thinner.

If you have more than one bit you might try another; it might be a little wider.

[George]

Pete gave the right answer. Makes the piece left behind a touch narrower, while the bit still takes the same amount.

Sounds like you made something similar to a tablesaw jig. You can try gluing some paper to the side of the pin and seeing how that does you. Should work.

Of course, you could make your next jig this way and have the microadjust built in. Works great.

[Jeff]

Mine was modeled after the table saw jig because I had been using the table saw to cut them. I was sick of changing to dado blades so I ported my table saw jig to the router table.

Thanks, Jeff

[Jeff]

make finger joints on my router table. I'm using a

Can you recommend a brand of extended set glue that you like?

Jeff

[digitect]

Yes you can. Here's a jig that illustrates a rather complex form of the adjuster

it doesn't explain it.

If you use a screw with a known pitch, you can calculate the exact amount of movement ("lead") each turn or portion will produce. The common example is a 10-32 scew--each turn produces 1/32"(0.3125") movement. So an eighth of a turn is 1/256" (0.0039"), a very fine adjustment indeed. Mark the screw head and use a paper marking circle with 10 degree increments to keep track of even more precise fractions of turns. 11.52 degrees equals 0.001" although that won't divide a circle evenly.

My own jig is simpler, I used oak for the moving face and an insert nut in a tailpiece glued onto face of the backboard. When set, I just clamp them together.

[Roy Smith]

There's something cool about an article that shows a beautiful walnut jig being used to make something out of "old dried up, splintery pine scrap", even if it is just a test piece. :-)

[Roy Smith]

I've got a fence for my router table I made like that. If you use a 1/4-20 bolt, the numbers work out easier. 1/5th of a turn is 0.01 inches, and with a little care, you can make 0.001 adjustments, which more than qualifies as an RCH when working with wood.

Compress a spring under the bolt head when you assemble it to reduce backlash.

[digitect]

Me too, sometimes jigs end up being more fun than the piece. (Actually, sometimes jigs are the whole reason to make the piece! :))