Mill & drill press tramming tool

[bobs409]

After seeing a few video's on these, I had to make one. This is so easy to make and works so good! Setting your equipment is no longer a hated task.

I can't take any credit for this as similar ones are sold commercially and plenty of vids on you tube but here's how mine was made.

(1) 6 inch piece of 1x1 aluminum bar
(1) 1/2 inch steel rod, about 6 inches long (A Chevy V8 fuel pump push rod in my case!)
(2) Harbor Freight dial indicators
(2) 10-24 cap screws


As noted, I opted to use a Chevy V8 fuel pump push rod that I had lying around since it's perfectly straight and hardened it was a good choice. I drilled the hole slightly undersized and used my shop press to push the rod into the square bar. The dial indicators I simply robbed from some other tools I made so I bounce those back and forth as needed. They set in a 3/8 inch hole that is then slotted with a 10-24 cap screw that cinches down to tighten them in.

I guess I'm lucky in that both my gauges are pointing to the same spot but it's not important anyway. Just 0 out both your dials and lower your quill down to your table or in my case, I trammed from my vise using 2 parallels. My mill was out a bit so with the mills head bolts loose (but lightly gripping yet) I just bumped it back until both gauges read the same value. (actual number doesn't matter, just so they both read the same)

It's quite fool proof and makes quick work of tramming your mill or even drill press tables.

[Ed ke6bnl]

A lot of old timers do not like this set up they like the old way of using a single gage. BUT I made one exactly like you did and love it especially to tram head on my round column along the X axis. Works great. enjoy

[DIYer]

Thanks bobs409! We've added your Tramming Tool to our Measuring and Marking category,
as well as to your builder page: bobs409's Homemade Tools. Your receipt:

Tramming Tool by bobs409

tags: dial indicator, tramming

[Trialnterror]

I made one also and was not sure if my 1/2" drill rod was perfectly 90* as it was made before I trammed my head, so I ran across one on fleebay (an edge brand pro tram) and absolutely love it! I'll have to tram my head on the Bridgeport and switch to the one I made and see if it's good? With the pro tram it comes with a magnet to calibrate both dials at a given location i.e. Bring the quill down so the 1st dial touches the magnet move down .050" then zero the dial, without moving the quill (preferably locked) rotate 2nd dial to magnet location then zero the 2nd dial and then the head square is calibrated! Then tram head accordingly

[pigpen60]

How do you zero it?

[Toolmaker51]

Who's he calling 'old-timer'? The reason for a single indicator is finer measurement; by increments and repeatability. Legitimately, and per inspection standards, instruments used commercially are acceptable to 4x finest graduations.
So we use an .0005, good parallels to 'skip' over the Tee-slots, occasionally after sweeping a fine stone over the table for nicks.
1] Wipe clean table & parallels with solvent/ nonabrasive hand cleaner/ or water based cleaner. White paper shouldn't expose any remaining smudge.
2] Lower the table and extend the quill just short of full travel [not against the stops]. The added extension will magnify error.
3] Set parallels near front and back edge of table for nod, shift same distance apart for swivel.
3] As suggested, loosen the clamps for both trunnions [swivel & nod] just snug and sweep them simultaneously.
4] Approaching Zero in either direction, increase torque on clamp bolts as you would lug nuts across centers. This will displace the indicator, especially if clamps were too loose to attain movement and stable setting.
5] I usually finish with backing off worm screws to not bear on rack teeth fully, just touching. That way, a reasonable check in the future is when there is still minimal pressure on the worm.
This is how we used a very special genuine Bridgeport way back when. Equipped with optical scale readers in .0001's, it was our jigbore. Never used a more accurate type of reader before or since. They measure actual position, much like a vernier, instead of interpreting electronic signals. The limitation of electronics is in resolution, both have nearly same repeatability, optics have an edge in physical accuracy.
Another nice feature was a stainless rule attached at front of table. Below, a sliding tab and pointer, with about 1.5" travel, positioned toward 1/10 inch graduations. Once zero was set [scales or dials] you sailed between coordinates as fast need be by hand or rapids. Instead of counting .200, .400, .600, .800, 1.000, to 3.348 whatever, watch the rule and pointer, reading dial for final thousandths. No one can read a flashing readout faster, even counting rotations. It does require holding backlash on the same side [x+ or -] during use.

Like that?
Masking tape and fine point ink-pen will do the same thing. One on the table, one for the bed. Just count up to first setup.

[garycullen]

I love to hear from Old Timers! I'm 64 so I guess I am one. Thanks for input on how things got done. I dont have or want a DRO on my mill and have made some very hard hole layouts using ruler and dials while accounting for backlash. I dont suppose your near New Lenox, IL 60451? I would love for you to come to my shop. My # is 815-485-7010 Gary

[Karl_H]

How do you zero it?

If you only had one dial, you would zero it to your table, then rotate the entire thing 180º. You then measure the difference and adjust your tram to half the difference. Rinse and repeat.

With this set up, you zero out one dial to your table, rotate the entire thing 180º as before. However, this time, you zero out the second dial - using only the rotation on the dial and NOT the Z adjustment on your mill - at the same spot on your table that you adjusted the first dial. You now have 2 dials zeroed out the the same spot on one side of your table, but one is resting 180º away from the other.

If your mill is out of tram, one of the dials will be precisely on zero and the other will be off. If you adjust the tram to half the difference, as you did with only one dial, one of the dials will increase by that amount and the other will decrease by that same amount. When both dials are reading the same, you mill will be in tram (along that axis.)

It doesn't really matter if the center shaft is precisely perpendicular to the bar of if the dials are precisely the same distance from the center spindle. It is handy if both dials have the zero at the 12 o'clock position, but not essential. As you adjust the tram, the needle are going to become either toe in or toe out (pigeon toed or duck toed) so having the dials exactly symmetrical is not necessary.

One mistake I made was to make the bar too long thinking a longer bar would give more precise results. However, I made it too long so I could not rotate it the required 180º. Another caveat is to make the center spindle long enough that the dials don't collide into the mill.

Hope this helps.