|Project by Jeff||posted 2451 days ago||11274 views||27 times favorited||22 comments|
This design is from the Working with Tablesaws book from the “New Best of Fine Woodworking” series published by the Taunton Press. At the time, I was reading article after article and books specifically about jigs and fixtures. I’m a real geek that way I guess. Maybe I should have been an engineer or something of that nature…
Anyway, this is an MDF jig and is pretty substantial due to the density and size. It is ‘micro’ adjustable by virtue of the threaded rod and crank. The other advantage is the ability to lock down the movable part of the jig to the base that slides in the TS miter gauge slot once you have it where you want it.
1) Threaded brass inserts put into MDF require the workpiece you are threading the insert into to be sandwiched tightly between two other dense materials to eliminate swelling of the MDF. Thus, the use of a scrap of Padauk. Even at that, I threaded that insert slightly off from 90 degress and had to make a slight cut with the TS on the support to put the brass insert perpendicular to the base;
2) ensure, with much attention to detail, the face of the jig is perpendicular to the base (and your TS miter slot. Otherwise your tenons will not be square to your mortise;
3) ensure your material for the miter slot insert/slides are a snug but freely moving fit;
- 3/4” MDF
- “milkboard” or UHMW (found at Woodcraft, Rockler and other locations)
- Heavy-duty adjustable hold-down (I got mine at Rockler)
- Finely-threaded rod material
- Knob (design or your preference) and Crank handle.
- Misc nuts and washers per the design specifications
-- Jeff, St. Paul, MN