Tramming Issues

[aucran]

Hi all,
First all admit I'm still very much a newbie at this, but have been capable of making the parts I needed for awhile now.

After thinking I could improve the surface finish by fixing the tramming of my mill, I've been having a lot of trouble getting back to even as good as I had it.

For namesake, I'm going to call the 2 smooth bands of iron that the move-able jaw of the vise slides on as the "Bottom" of my vise.

>To start, I mount a Swiss Type Dial Indicator in a Drill Chuck and lower it deflect about 0.015" on the the Left side of the bottom of the vise and set the reading to Zero.
>Crank the hand wheel to move the DTI to the right side of my vise and take not of the reading.
>Loosen the 3 Bolts that secure the head of the mill to the Column and do my damndest to adjust 100lbs of iron to half the difference. Tighten up slightly on the bolts a bit, and move back to the Left side of the Vise.
>If there still an error in alignment, I try to adjust and go back and forth until I get an acceptable difference.

My trouble is, how can you tighten the 3 bolts without ruining your careful rotational adjustment of the Mill Head? I spent almost all night trying to get back to where I was before I gave up. I've only done this twice before, when I first got the mill and then when I got a new vise. I don't remember this being a issue before.
I do pretty simple hobby work and just want a surface I can slide my thumb smoothly over. Any advice would be greatly appreciated.


Also, I've considered purchasing a Spindle Square (the device with 2 Dial Indicators in it) that is supposed to make tramming quicker...but I imagine I would have the same problem with tightening the bolts as I'm having now. Only I'd have less hand wheel cranking to see it.

Thank you.

[dsdmax]

Assuming your column is square and you only need to adjust your head ... you need a couple things. First is a lead hammer (or a hard rubber one). Loosen the bolts but not all the way - there should be enough friction/pressure to hold it in place. You can then use the hammer to gentle nudge it in place. tighten the center bolt first but not all the way - work your way around clockwise - if your head still moves note by how much and the next time leave it our of tram that amount and tight the same way...

An even better method would be with the tramming aids originally proposed by machinechick (the design will have to be modified for the ihcnc ... ). you can find reference to them on this forum and in the CNC Cookbook: Software and Information for Machinists - you will also find more tramming tips there as well. Good luck.