Hi ADFToolmaker:
If you're committed to grinding pins rather than wire cutting them, here's a way I used to use (in the days before wire for me)
I built a rough and dirty cutoff machine from a pedestal grinder, and put a swing arm on it basically like a Deckel single lip cutter grinder but without the fancy collet system.
I welded a pair of vise grips onto a bracket I could slide along the arm, aligned so the pins could be clamped parallel to the swing arm axis (give or take a smidge).
I made no attempt to build a rocket science device; it was just for cutoff, not for finish grinding.
I made the swing arm long, almost down to the floor, so a cutoff movement was a big arc; almost linear over the distance needed to cut a one inch pin.
I got a cheap throwaway digital scale and bolted it to an end stop bracket so I could move the end stop predictably and set my zero wherever I wanted it.
I made a fine adjust mechanism for the end stop just like you see on simple height gauges.
All was made to be used; not to be a work of art.
It took a weekend to make, and I used a cheap shitty Taiwanese bench grinder to power it
This cutoff system worked like a hot damn.
The beauty of it was that it was very fast; the vise grips, crude as they were, were perfect for this application.
You could adjust them so a skinny pin could be grabbed without locking them and then driven past the wheel by swinging the swing arm, then swinging it back and releasing the pin.
I could whang through a gazillion pins really fast, maybe 2 seconds per pin for a 1/8" pin.
Big pins could be clamped very securely just by adjusting the vise grips to lock on the pin.
That way a big pin could be cut by bouncing the pin into and out of the wheel to keep it from overheating.
I could control the pressure easily; in fact the whole affair was something like a chop saw except I moved the pin instead of the motor and wheel.
Even though I'm right handed, I mounted the affair on the left side of the grinder; that way I could put all my pins on a little table on my left side and grab them without even looking at them. (I'd sort them first, obviously, so all of the same size and length would be cut as a batch).
I could also hold them against the stop with my left hand while I squeezed the vise grips with my right hand, and then release the pin into my left hand without burning my fingers.
The beauty of this wonky contraption over a chop saw was its blazing speed; the clamping, cutoff and unclamping motion is all done with the same hand and it never leaves the vise grip handle.
You can set up a bucket with water underneath your cutoff station and just drop the pins in as you cut them.
You can cut bolts, dowel pins, barstock; all kinds of useful stuff (come to think of it, I'm kinda nostalgic for it now!!)
For grinding pins, I ALWAYS stood them up instead of sidewheeling them.
I'd grind them all to +.005" in one increment, using the grinder as if it was a shaper, and toss them in a water bucket.
They'd usually expand just enough from the heat that I'd have maybe 0.002" left for a finish pass by the time they cooled again.
Then I'd re-dress the wheel and finish grind them to length, putting the pin heads on the mag chuck so I always knew exactly where I was.
The pin grinding fixture was a pair of angle plates mounted back to back with a pair of keys between them so I could slide them up and down.
The upper angle plate had a vee ground into the end of the short leg (the horizontal one) and a Destaco over center toggle clamp bolted on.
I'd leave the mag chuck always on, pop a pin into the vee with the head a bit above the mag chuck and put a smidge of pressure on the clamp; enough to align the pin in the vee, but loose enough so I could still slide the pin up and down.
I'd give the chuck right under the pin head a quick wipe with my fingers and push the pin down until it sucked itself onto the magnet, then clamp the Destaco.
I found it best to load the pin before I did the wipe; that way the pin blocked all the shit on the fixture from falling onto the mag chuck when I pushed the pin down.
For shortie pins, I'd either use a mag block or I'd clamp a mag base from a dial indicator onto the upper angle plate at the proper height.
(I surface ground the top of the mag base to make it parallel to the bottom, and just blocked it up to the right height with 123 blocks and parallels).
Again it was simple and fast to set up on the surface grinder, and it was fast to use and very accurate, making nice smooth pin faces that were dead nuts square and dirt simple to control the length.
Then I got the wire EDM, and promptly abandoned the setup, so unfortunately I don't have pictures.
On a last note; a couple of points from my experience.
Some of my toolmaker buddies built enormously elaborate multi pin cutoff fixtures over the years.
All were slow and difficult to use; hard to load, hard to get all the pins down on their stops, hard to maintain with all the shit and corruption around grinders.
I also tried a DME pin grinder once; I was not super impressed even though I'd had a big boner for one before I got to try it for real.
Slow, not that accurate; just nothing to write home about. (besides did I mention I hate sidewheeling pins)
Cheers
Marcus
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