I have had this Leigh dovetail jig for more than a year and have yet to tune it so I can use it.

From wood stuff 2010

When I first got it it was an old D4R so I upgraded the clamp mechanism and added a bit of adhesive sandpaper to the clamp bars.
The first couple times that I tried this machine I found that the wood wanted to slide under the clamp bars so I put sandpaper strips to control that .
I also had difficulty the 1/4 inch shank bits that I had on hand wsliding out of the collet adapter and spoiling the joints.
I replaced the collet with a new one from Lee Valley and purchased *8mm shank* bits as well as an *8mm adapter*.
I'm surprised how much better this combination seems to work in my router.
It makes me wonder why the industry ever produced quarter inch bits as they have been a pain in the ass since I started woodworking.
My "go to" router has become a Triton three and a quarter horsepower machine which has all the right features but of course, with a large motor, becomes a bit of a behemoth to move back and forth on the job.

From wood stuff 2010

"So I decided to treat myself and purchased sliding vacuum system and extension table from Lee industries.":http://www.leighjigs.com/vrs.php

From wood stuff 2010

Essentially, it's a long smooth sheet of aluminum fixed in place by 4 rare earth magnets. On the underside they have attached a vacuum that slides along as you route. The end result is no more sawdust in my socks a convenient table to rest my router on and keep it level during the machining process. the two wire arms adjust to fit any router and the entire mechanism slides like silk with the addition of a bit of wax to the surfaces.

While setting the jig up to do a few test pieces I noticed that the fingers had several small imperfections from the casting process that made my router stall and catch in places in places making movements back-and-forth a bit jerky. I put a fresh piece of 180 grit sandpaper in my palm sander and gave all the mating surfaces a light buff. Just enough to remove imperfections.
I then gave the entire mating surfaces a light coat of Johnson paste wax to the base of my router.
The router slides on the table with one hand now!

From future projects 2010

Next I cut some pieces pine 1 x 4 and ran a couple of test joints shown here.

From wood stuff 2010

From wood stuff 2010

These joints are not perfect but they do show me that I'm on the right track.
The attached vacuum makes it extremely simple to rest the router between passes. I used to have to lift it over top of the jig and set it down between each pass.

From wood stuff 2010

From wood stuff 2010

Rather than try to hook up the Vacuum line to my central dust collection system from a 1 inch intake line I chose to use a small shop shopvac located on my storage shelf and operate the on/off switch with this auto switch so that each time I turn the router on the vacuum automatically goes on and runs for an a additional 10 seconds after I switch it off

From wood stuff 2010

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