Saturday, March 16, 2019

Parallels

I know you are supposed to use parallels to put a workpiece above the jaws of the vise.  I have never had any luck using the Sherline parallels.  They just keep falling over before I can get the has clamped on to the workpiece.  Why?  I found a very good YouTube video (actually several) about using parallels, and the problem is now obvious.  All the parallels were thick enough to stand on edge long enough to get the workpiece on top.  Like everything else about the Sherline mill, the vise is tiny and so are the parallels.  They are so thin that they will not stand up on end.  

One video showed a very clever alternative to parallels: put a twist drill or two under the workpiece.  The shank part is very consistently round and diameter.  If you have several identical worn out drill bits, you have a new use for what would otherwise go in the recycling bin.

I started thinking: why not magnetic parallels that will stick to the jaws?  Sure enough, they are made, but they are big, for manly mills, not ones still waiting for puberty like the Sherline.  But they are steel, and if you stock a piece of steel to a strong magnet for a while, it in turns becomes magnetic.  Tomorrow's  experiment!

Sherline's parallels will stick to a magnet but not hold the field.  Stainless steel?

6 comments:

  1. Hmm, I wonder if a strip of magnetic tape would hold a parallel to the vice?
    I'll check that tomorrow. I have a roll of the stuff. Might be 3/8" wide, maybe 1/2".

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  2. Good point.
    I knew there was a roll of small supermagnets stuck to the side of the refrigerator, and they were thin and around a half inch in diameter.
    One magnet stuck to the side of the parallel that doesn't touch the vise had enough pass through magnetism to keep the parallel against the vise, and when I put the magnet on the side of the parallel that touched the vise, it held the parallel upright very well.
    I couln't remember where I got the magnets, and I didn't measure them because your mill and your vise is going to be a bit smaller than mine.

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  3. Clayton,

    found the roll of mag tape. It's 1/2" wide x .058" thick. Has a peel-off backing covering sticky tape. Anyway, even with the paper cover, it holds a full size parallel to a drillpress size vise. (old stuff, so no guarantee the sticky side is still good, although it sticks to my finger)

    I'll throw some in an envelope, if you want. Also have a bunch of scrap pieces of magnetic signs, about half as thick, that I can send along.

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  4. Some stainless steel is magnetic. I don't recall the number. Maybe 304? Tends to be slightly weaker magnet holding than regular steel, IIRC.

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  5. Will: Thanks. 36 Sunburst Rd., Horseshoe Bend, ID 83629

    I am getting more competent with the parallels, but this would help a lot.

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  6. Will: Thanks, arrived. The Sherline vise turns out to be aluminum, but the new sine vise is steel and this should help greatly.

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