Tramming a Harbor Freight mini mill

There are some web pages describing how to align the head to the column on a mini mill. Here's one, and this one is a little more detailed. BTW, you don't need to remove the column in order to evaluate how bad (or good) the alignment is. I evaluated my mini mill and decided that it was good enough for most of my needs.

The author of the first first link talks about using a special test bar ordered from McMaster-Carr, but any accurately ground rod will do. The author of the second link used a rod scrounged from a printer. I have some linear shafting I use for this, it's available for cheap on ebay. 1/2" drill rod would work OK, too. You don't want a rod that is small enough to be significantly deflected by the force of the dial indicator plunger....but if using RDM that may not matter.

Unfortunately, the mini mill design doesn't have a built-in way to adjust the alignment. You have to use shims on one axis and hope there's enough rotational slop in the other to get to where you want to go.
 
Thanks for the response mickri. No, I'm not trying to tram the head to the table, I would have done that next, I'm trying to tram it to the column and I found that the head is tilted to my right. I put a dial indicator in a collet, swung it to my right, while facing the machine, turn it so its touching the left side of the column, swing it to the oppisite side and the indicator is .02" or .5mm lower/deeper or if I have the indicator barely touching the left side of the column swing to the right hand side of the machine its not touching the column.

Just to give more context, I took the machine apart to lift it onto my bench(hurt my back in the Army in the late 90's needed to split it to pick it up), I then tried tramming it. I could get head trammed to the table, that the column was not tilted left or right but if I moved the X or Y axis my measurements were way off not even close to being the same. So I started trying to tram every part that moved or I took apart, thats when I noticed that the head is not square to the column. If it was, I would have moved on to tramming the head to the table but I thought I should ask for some advice before I ignored the tilt or shimmed it. The head and motor mount to another block with 4 bolts, that second block mounts to the column, so the head does not move in relation to the column, moving the head up or down does not change the tilt to my right, the measurements do not change, so could I ignore it?
 
Thanks homebrewed, but thats not what I'm trying to describe. It seems to me that the 2 casting that make up the head are angled to my right, I measured it by puting a indicator in the spindle with a collet measing the distance from the spindle to the left hand side of the column then swinging it the the right hand side of the column and getting a difference of .02" or .5mm further away on the right hand side. But I do have some old rods from printers and will use this to measure the nod, thanks again.
 
Higgite I hadn't thought about that and have not experienced that on my round column mill/drill. I use what I call the longest tool method as described by the Lazy Machinist in one of his videos to set the height of the head. By doing that so far I have not had to move the head to change tooling on my round column mill drill. Maddthom does not have a round column.

Maddthom I think that this is what you are trying to achieve. https://www.homemodelenginemachinist.com/threads/mini-mill-spindle-column-alignment.5337/
 
mickri said:
Higgite I hadn't thought about that and have not experienced that on my round column mill/drill. I use what I call the longest tool method as described by the Lazy Machinist in one of his videos to set the height of the head. By doing that so far I have not had to move the head to change tooling on my round column mill drill. Maddthom does not have a round column.

Maddthom I think that this is what you are trying to achieve. https://www.homemodelenginemachinist.com/threads/mini-mill-spindle-column-alignment.5337/
Click to expand...



Thats exactly what I'm describing, and the info I was looking for, thanks mickri
 
tomfiii said:
How did you tram the column without using the head ?
Click to expand...

I don't know if it was a correct thing to do, but I used a magnict base mounted to the table loosened the 3 bolts mounting the column tilting mechinism to the table, cranked the X axis back and forth and tapped the column until both sides of the column read the same.
 
You need a picture or drawing of what you are doing,as that sounds like squaring column to Y axis.
 
Do I have the axis mixed up, I thought the table moved in X and Y, rasing the head up and down was Z, am I wrong?
 
mickri said:
Higgite I hadn't thought about that and have not experienced that on my round column mill/drill. I use what I call the longest tool method as described by the Lazy Machinist in one of his videos to set the height of the head. By doing that so far I have not had to move the head to change tooling on my round column mill drill. Maddthom does not have a round column.

Maddthom I think that this is what you are trying to achieve. https://www.homemodelenginemachinist.com/threads/mini-mill-spindle-column-alignment.5337/
Click to expand...
Mick, I agree. I do the same when I can, just on general principles, but my mill has a quill, as I imagine yours does. Mini mills like the OP's don't have quills so he has to move the head up and down for drilling, plunge milling, etc., so an "in tram" column is actually more important to him than it is to us. Adding to his woes is the HF mini mill has a tilting mechanism so the column can be tilted left or right for angled drilling, etc., and it has to be re-trammed when you "untilt" it. Theoretically, the head should be aligned with the column from the factory and not need separate tramming, but Murphy is alive and well. ;)

Tom
 
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