Thursday, January 12, 2023

Current Frustration

The gratifying activity includes:

1. New semester starting.

2. Providing historical research for the California baton ban; the California assault weapons and large capacity magazine ban; Oregon Measure 114, and an upcoming case in Naperville's assault weapons ban.


I bought that wonderful Taiwanese cross-slide vise and having used it for a while had been very gratifying.   It works so much better than the PRC version.

However, the marvelous Tapmatic tapping tool requires a stop rod to catch the mechanism and causes it to start reversing direction and back the tap out of the hole.  With the old vise, I drilled a hole in the vise for a .5" steel rod but I do not want to drill holes in this beautiful vise.  Besides, depending on the position of the quill relative to the cross-slide vise, the rod did not always end up in a useful position. 

So, I decided to build something that would slide back and forth above the clamping screw.

I could I suppose have carved a U out of a block of aluminum but it was simply easier to cut a piece wide enough to cross over that clamping screw with two "legs" going down the side.  I will hold the legs in position on the ends of the bridge with 8-32 screws and then 1/4-20 thumbscrews in the legs to lock the bridge in position.   A 1/2" hole in the bridge for the stop rod with a thumbscrew to hold the rod in place.  The entire assembly can be repositioned on whatever position is most useful.

The hard part is how wide is the bridge.  Getting an accurate width was difficult because my micrometer cannot go low enough because of the clamping screw.  

I obviously mismeasured and ended up with a bridge just narrow enough that the legs will go down over the edges.  I then noticed that I could measure at the Jaws which are the required width: 5.78". Unfortunately while I can mill that bridge a bit smaller, I cannot mill it any wider.  So I need to recut that bridge from a existing piece of aluminum stock.  

Once cut to 5.85" or so, I only need to mill the ends to square then drill and tap 8-32 holes at .34" and .67" from the ends centered in the .5" thick bar.

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