Tramming a Tormach.

[Willyb]

Hi Guys

I am in the process of Tramming my Tormach Mill and have a couple questions on the correct way to do this operation.

First some back ground. I decide to build my own Stand, the Frame being made out of 2" square tubing, covered with sheet steal. I have a screw type adjuster at each corner of the Stand for leveling the Stand to the Floor. I have four 3/4" steel mounting pads for the Mill to sit on. These Pads are in turn sitting on the 2" square tubing.

My initial check of the Tram I came up with the following numbers?

Front Y = Zeroed Dial Indicator.
Rear Y = -0.003

Left X = -0.005
Right X = +0.002

So the Y is out 0.003 (Table low at the rear)
And the X is out 0.007 (Table low on left side)


(Questions)

(1) For my above numbers were would you start inserting the shims? Is this trial and error?

(2) I understand that the Tormach uses a thin sheet of hard rubber between the Mill Base and the mounting pads on the Stand. Is this rubber necessary? You would think that the rubber could cause changes in the Tram depending on the weight put on the Mill Table.

(2) I also understand that Tormach recommends shimming between the corner of the Mill Base and the Stand to adjust the Tram. I always thought that you shimmed the attachment points between the Vertical Column and Base and/or between Vertical Column and Mill Head to adjust the Tram?

(3) What would you think the Mills mounting bolts should be torque to? I don't think they should be to tight. Was thinking of approximately 5 to 10 ft. lbs.

(4) Do you know of any good articles on Tramming a Milling machine?


Thank you for your help with my questions on Tramming a Mill.


Willy

[philbur]

Forget about shims, at least for the moment. If you do all the relevant measurements as defined in the test certificate (in the correct sequence) you can, with a bit of detective work, determine exactly where the problems are. You can't jump right into the middle of a test sequence and expect to understand anything. Do the checks without bolting the mill to the stand. There are multiple reasons why either the x or y-axis is off.

Regards
Phil

Hi Guys

I am in the process of Tramming my Tormach Mill and have a couple questions on the correct way to do this operation.

First some back ground. I decide to build my own Stand, the Frame being made out of 2" square tubing, covered with sheet steal. I have a screw type adjuster at each corner of the Stand for leveling the Stand to the Floor. I have four 3/4" steel mounting pads for the Mill to sit on. These Pads are in turn sitting on the 2" square tubing.

My initial check of the Tram I came up with the following numbers?

Front Y = Zeroed Dial Indicator.
Rear Y = -0.003

Left X = -0.005
Right X = +0.002

So the Y is out 0.003 (Table low at the rear)
And the X is out 0.007 (Table low on left side)


(Questions)

(1) For my above numbers were would you start inserting the shims? Is this trial and error?

(2) I understand that the Tormach uses a thin sheet of hard rubber between the Mill Base and the mounting pads on the Stand. Is this rubber necessary? You would think that the rubber could cause changes in the Tram depending on the weight put on the Mill Table.

(2) I also understand that Tormach recommends shimming between the corner of the Mill Base and the Stand to adjust the Tram. I always thought that you shimmed the attachment points between the Vertical Column and Base and/or between Vertical Column and Mill Head to adjust the Tram?

(3) What would you think the Mills mounting bolts should be torque to? I don't think they should be to tight. Was thinking of approximately 5 to 10 ft. lbs.

(4) Do you know of any good articles on Tramming a Milling machine?


Thank you for your help with my questions on Tramming a Mill.


Willy

[ErnieD]

Willy,

There is a Yahoo Tormach group. The very problem has been addressed among the people in this group. Join this group and do a search on tramming, shimming the column etc. and you will find some good info. Also try e-mailing or telephoning the tech people at Tormach.

ErnieD

[keen]

hi Willy - I have made a similiar steel stand too. but i think any stand - even one that is machined flat on the top - may not be exactly flat when it sits on the floor. Everything flexes a little. I agree with Phil - leave the bolts loose. well I observed that the machine sat on my stand without a gap under any corner - so initially i have just "nipped the bolts up" for security in case of an earthquake - we get here. I am lucky - mine tramelled up well - it is my most accurate mill ! i need to move the machine on the floor from time to time - and this will cause at least slight flexs and changes. if you are keeping your machine in the same spot. you may be able to do better. If you are on concrete you could bolt the stand down - then fit shims under the macine corners if any gaps - then bolt it down firmly to 'tie the structure together" and probably gain a little more ridgidity - then finally check trammell. - but I think you would measure little change.