Among the Best Machining Tool Purchases Ever

About a year and half ago, I sang the praises of a very reasonably priced mill vise from Little Machine Shop.  

My love continues.  The Sherline mill vise is adequate to hold small workpieces but even then it does not have the grip required for even relatively unaggressive cuts.  This one does.  Being made of steel not aluminum, it has tolerated some excessive Z-feed errors that at a minimum made the Sherline vise pretty ugly.   

The SHCS that provides the force to hold down the jaws also kept rounding inside so I kept replacing it.  No problems so far with this vise, and I have really locked this vise down.

At the same time, I purchased a very nice set of parallels from them that have proved far superior to Sherline's parallels.  They are thick enough to stand on their own, which matters a lot when you are stacking them up to hold relatively thin workpieces high enough to stick above the jaws. Pretty much anything you need for a micro or mini mill is there.

Low-Profile Focuser

 I still cannot get the lathe chuck to hold the 1.5" OD tube.  Next step is probably disassembly, cleaning, and reassembly.  On the plus side, I found a source of 1.259" ID 1.375" OD tubing, so no need to do any turning.  The downside is that I still need a step to prevent the tube from falling through the base, and there are only a few threads to hold an 8-32 thumbscrew in place to prevent eyepiece motion.

Solution: Machine a sleeve about .25" long from that 1.5" OD tube into which the 1.375" tube slides.  (Such a short piece should be held adequately by the chuck, and I will be boring the inside, not turning the outside.)  Glue with epoxy to hold in place.  Now I have .25" of aluminum to hold the 8-32 thumbscrew.

No need for epoxy; I bored that .584" long piece of 1.5" OD to a diameter where it would just barely press onto the 1.375" OD tube.  Then I tapped it for a 6-32 knurled head thumbscrew (which I seem to have bought 10 of them, some years back).  I also bored the 1.259" ID tube just slightly larger so that all my eyepieces slide in, and only the thumbscrew holds them in place.  

I had thought of making a brass compression ring to prevent the thumbscrew from marring the barrels, but this is a plastic coated thumbscrew, so no need.  Those brass compression rings are a real pain.  You have to excavate a shallow (.050") channel with a reverse rake boring bit, then cut a very narrow piece of brass to fit in the channel.

Because the OD of most of the new tube is 1.374", I am making a new base with a 1 3/8" hole.  That is mostly waiting for the slotting program.