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daved20319
03-01-2011, 02:54 AM
This is probably a silly question, but even after pages of searching, I don't have a definitive answer, so here goes. All the info I've seen on tramming a mill seems to be referring to round column mills, so the question is, do you also need to tram a dovetail column mill, specifically, a Grizzly 0619 (Sieg SX3)? And if so, what's the procedure, preferably in words of one syllable or less :-).

After much research, I've decided that, for my purposes, this is the best bang for my bucks. I learned long ago that spending time setting up a new machine before using it is time well spent, I'd like to have my new mill as close to perfect as I can get it. I'll be picking it up sometime in the next couple of weeks, would be heading out tomorrow but winter decided to move in again. Thanks in advance, gents.

Dave

Black_Moons
03-01-2011, 04:03 AM
Typicaly you tram the X rotation of the head in a square collumn mill by loosening the alignment bolts and hiting it with a deadblow hammer to move it.. But you rarely ever loosen the collumn and adjust the Y rotation/Z axis alignment of the mill. Maybe once when you get it if it tests bad.

philbur
03-01-2011, 05:43 AM
First you check that the column is square to the table in both planes, then you check that the spindle axis is parallel to the column axis in both planes.

Quote:

"I'd like to have my new mill as close to perfect as I can get it"

It will never be perfect. How close you get depends on the degree of effort you input. It's a process of diminishing returns. At some stage through the process you will concluded that: "it's good enough for the girls I go with”, so you may as well start with that premise. It saves you from a lot of none productive effort. Anything better than 0.001" per ft, is wasted effort for a machine of this calibre.

Phil:)

DougC_582
03-01-2011, 05:58 AM
The mill head of the 0619 tilts left-and-right, so yes--it must be trammed that way and re-trammed, if you rotate the head at all.

There is no other method for easily nodding it the other direction (in regular use) but I've not seen that there was an issue with it that I'd have to fix.

There is a spring-loaded key that is supposed to help the mill head stay "nearly" centered, you need to hold it turned to tram the head. I use a piece of coat-hanger wire to hold a hex wrench for this. It is a pain in the butt, and doesn't really help much with anything that I can tell. If I ever take the head off, that is one feature that is definitely coming OUT.

The two nuts that secure the head also make it squirm as you tighten them. Check & re-check as you're tightening the bolts a quarter-turn at a time. :)

50BMGBOB
03-01-2011, 06:09 AM
Good question, as I just ordered the same mill.

dian
03-01-2011, 07:46 AM
is there a way to tram a non-noding mill in the y-z plane? i reckon shimming under the bolts is not a great idea, you probably loose a lot of rigidity.

philbur
03-01-2011, 08:16 AM
Scrape the mating surfaces.

Phil:)


is there a way to tram a non-noding mill in the y-z plane? i reckon shimming under the bolts is not a great idea, you probably loose a lot of rigidity.

dian
03-01-2011, 01:18 PM
i will. can you come and help me?

form_change
03-02-2011, 04:05 AM
It's worth pointing out that machine standards (Schlesinger et al) allow some deviation from square for mill tables to the axis of the spindle, and a whole lot of other things for that matter.
While you can try getting your mill as square as you can, these standards have been used for many years to define acceptable geometric relationships for large industrial machines. I can't find my Schlesinger but Connelly suggests (and all these standards are usually about the same)

Table top square with spindle (right and left) 0.001" in 18"
Table top square with spindle (front and rear) 0.001" in 12" (preferably low at the back)

These numbers are for larger and far more rigid machines. Please don't take this as a slight against your mill, but they do show that even big, solid (rigid) machines were expected to vary a little. I would not expect those sorts of numbers from something like an X3, although you could regard them as something to aim for if you wanted to. I was horrified the first time I measured my lathe but it's getting better.
As a hobby machinist I define my success by 1) how much I can improve my machines while they are in my keeping and 2) how well I can compensate for the less than new condition of what I have. At some stage I hope to meet in the middle...

Michael