# 8520 Owners, Tramming?



## 34_40 (Jan 2, 2016)

Have any of you owners of the 8520 Clausing (or Johansen) vertical mill completed a tramming of the head/table?  If so, can I ask you how youaccomplished this?

I know the basics and the theory but I don't seem able to hold it at zero.  When tightening  the fasteners at the ram it seems to move ever so slightly and leaving it out of zero, I tried compensating and while it's okay... I just want zero, not a half thou or thereabouts...

Hence the question. How do you guys set the head to zero?  Or do you?!?!?!


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## JPigg55 (Jan 2, 2016)

Mine's a bit of a pain, but able to do it. I've considered either buying or making a tramming tool to make it easier.
I snug the over arm locking blots just slightly and use a rubber mallet to gently tap it to bring it into tram.
It's a lot of back and forth sweep, tap, sweep, tap, sweep.....
Might check your gibs as well, make sure your table isn't loose. That can affect it staying in tram as well.
Been thinking of machining some sort of clamping collar for the over arm that has a foot that would rest on the column with an adjustment screw that could be used to bring into tram and hold it.


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## Terrywerm (Jan 2, 2016)

I do much the same as JPigg, but I do have a tramming tool on the drawing board, and have the twin dial indicators and stock on hand for it. Just have to get going and get it made.

I do like the idea of making an adjuster to clamp on the overarm, allowing a person to dial it in with a couple of set screws.

One other thing to check is your indicator mount. Make sure that any clamps on it are clamped solidly and are not allowing any movement. I had a similar experience one time and it drove me nuts. I finally took my indicator mount all apart and thoroughly cleaned it, then reassembled and tried again. It is possible for microscopic chips to get between the clamp and the shaft, allowing the clamp to move ever so slightly, causing problems with consistent readings.


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## 34_40 (Jan 2, 2016)

Thanks Guys, good to hear that I'm not the only one..  I do the back and forth..  tap tap tap... and re-read and tap tap tap....
But when I go to do a final snug. it seems to move ever so slightly.

I was also thinking of coming up with a clamped ring on the ram and an arm that would extend down each side with an adjusting bolt in it.


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