I spent a couple more hours on the twin screw this morning. I had a few details to straighten out.
I went ahead and split the vise. I decided that the front leg lamination should run top to bottom. So I pulled the vies and split the block. I mentioned slipping in my last entry. So when I remounted the blocks I used a liberal coating of 3M super77 spray adhesive. Seems to have done the trick. Now the blocks are rock solid to the bench top, yet if need be I can still remove them.
Next detail to attend to is the taper on the chock. I placed a thin scrap at the top of the vise and closed it down snug. I measured about .10” deflection top to bottom on the chock. So I transfered that measure to the bottom of the chock, struck a line, and then used my hand planes to remove the material.
I started with my no78 rabbit to establish a good depth on the low end. Then I swapped over to the no5 for bulk removal.
Winding sticks are your friend for an operation like this. I imagine it is pretty easy to introduce a twist doing this taper.
After getting roughly where we needed to be I pulled out the no608 and evened it all out.
Next up was the carrier pins. Not sure if that is what to call them or not. Basically a borrowed idea from the Veritas twin screw. These 3/8in steel pins keep your work piece from coming in contact with the vise screw. I had to run mine inboard of the screws, they would be better served outboard but my mounting bolts were in the way. Who the heck is in charge of this design anyways???
Note: I used the drill press to make the mounting holes. These holes should be tight tolerance so the pins press fit into them. They are also perpendicular to the tapered face. The easiest way for me to achieve this setup was to put the chock taper down on the DP and drill all the way through it.
I then used a transfer punch to mark the mounting block. I used an oversized brad point drill to make the mating clearance hole in the mounting blocks. Easy peasy.
That pretty much wraps up the twin screw. I will flush plane the mounting block to the leg and apron tomorrow. As it is, it is up and operational. The flush trim is for improved grip, aesthetics, and just a finishing touch.
time log: 35hr
-- Doug, woodworking in Alabama