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Hate Your Pin Vise? Build a Better Mousetrap....


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This is my first tech thread, so any kind suggestions or constructive criticisms will be welcomed. I have had a German-made Mascot pin vise since the mid-1980's. It is still a serviceable unit, and works fine as pin vises go. My problem with it has always been its inability to hold a small bit straight in the infinity collet, not since day one has it done this to my satisfaction. IMG_2344_zps9asz401w.jpg 

Recently, upon re-entering the hobby and evaluating all of my tools, i decided that i would try to build something better. But first, a little more background.... A few years back i had a career change; for 25+ years i had been an auto parts counterman in dealerships, with a 9 year stint in the middle as an assembly mechanic in the paper-making-machinery industry. In 2010 after a layoff from a parts job, i decided to go back to school for CNC setup & programming. I now work as a programmer/setup machinist, running vertical machining centers in a toolroom for a local company that specializes in making deep-drawn metal stampings in progressive-die presses. This has afforded me a familiarity with various tooling systems and opportunities to do some things for myself. We use ER (Erickson) series collets at work for holding drills and endmills. ER16's go from about .030 up to about .437, and ER32 for larger shanks. They work nice and even the cheap import collets will hold .0002 total indicated runout in a good collet chuck with a good nut. I got to thinking about my pin vise one day and wondered how small the smallest ER series was and what the range was and if a collet chuck could be made into a pin vise.

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Enter the ER8 series. The collets go down to .2mm (.0078") and up to 5mm (.196); perfect!

more to follow....   

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I purchased a low-cost import ER8 collet chuck on Ebay for about $15.00, and 5 different size collets; .2mm, .5mm, 1mm, 1.5mm and .125" from various online sources.

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Since i don't operate the CNC lathes, i told Curt, the day-shift Mazak guy what i wanted. About 1.75" of length needed to be removed and the end turned and threaded for the knob from the old pin vise. 

The Mascot pin vise uses a 5/16-40 (pretty unusual) thread form. The threaded portion is about .200" long. The major and minor diameters as well as the thread pitch diameter were all found in Machinery's Handbook. This is essential information for the lathe programmer.  About 1/2" of length was turned down to the major diameter.

  

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One word of caution about using the collets; the collet "snaps" into the cap before screwing onto the chuck. The picture below shows the collet installed in the cap correctly.

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The collet can easily break if you attempt to place the collet and tool into the chuck and then try to screw the cap on.    

 

Mine also required a 9mm wrench and a 12mm wrench to tighten

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The finished product....

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Very nice work.

Also, don't overlook your local tech college. It's a one-class-period project for a reasonably bright and CNC functional student.    

Or...ummmm...some old geezer (like me) who can operate a freaking...I know this is scary blasphemy...MANUAL lathe without having to resort to CNC programming to make ONE part. Whole deal should only take a few minutes...maybe half an hour...with actual micrometers and dial indicators and stuff. B)

Nice conversion work, anyway, and a nice idea here. :D

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OK, maybe I'm a bit dense, but this thread is mystifying to me.

I have an el-cheapo pin vise from Hobbytown USA with two collets, one for small bits and the other for larger ones. They are the "infinite" type that grab the bit as you tighten down the end cap. I have never had any problem with the bit being held any other way than perfectly straight.

This seems to be a solution to a problem that doesn't exist. Or am I missing something? :blink:

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Why not knurl the nut so you don't need wrenches?

I have quite a few pin vices since it's easier to buy one with bits that just bits. All of them hold bits nicely, even the worst is good enough for hand work. Of course I also use a brace and bit in my hand wood working and I have no problems there either. The one I have like the picture in the original post is my favorite other than the fact that my two most used bits require me to flip the collet.

A manual lathe would be my preference for a one off part like this. 

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