Blue Dovetail Jig Problem

I have one of those generic dovetail jigs and need help. I have been using a 1/2" 14 degree bit and a 7/16 bushing with 1/2" template, and the fit is very tight, too tight to hammer together, but close. I have tried different depth and settings with no luck. Even tried different size bushings. I think this jig could produce reasonably good half blind dovetails but I haven't had any success. Gotta be a way! There are probably a lot of these jigs out there and someone must be able to use it to get good dovetails. Yeah, I know it is a piece of junk but I think if I can get it set up I will leave the bit in a spare router and just dedicate it for that purpose. No instructions came with the unit. What size bushing do you use and what bit? What depth of cut? Many thanks for any advice.
Regards
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Charlie Campney wrote:

If you will reduce your depth of cut a couple of thousandths, I think it will fit OK. Fred
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Charlie,
I have an old Craftsman half-blind dovetail jig which I have used for 35 plus years. I keep an old Sears router permanently setup just for this jig. My router bits don't give an angle, but I put a bevel gauge on one and it appears to be exactly 14 degrees, so I'm guessing that is correct -- they are marked 1/2" width, and that corresponds with my owner's manual (which is available on OWWM.com BTW).
My directions call for 7/16" OD template (collar), and the spacing of the combs on my jig are also 7/16". The manual says to start with 19/32" extension and adjust the fit by raising or lowering the bit. I have my bit currently just a fraction below 19/32", closer to 18/32".
--
Ken Vaughn
Visit My Workshop: http://home.earthlink.net/~kvaughn65 /
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Heighten to tighten (expose more of the bit) Lower to loosen (expose less of the bit)
charlie b
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