Tramming the head on a bridgeport

[friday466]

What is the wuickest and easiest way to tram the head on the a bridgeport mill.

[bob_s]

Try looking at Ron Smith's Virtual Machine Shop

http://www.jjjtrain.com/vms/mill_mov...vert_hd.html#7

-bob

[Leigh]

Here's a very long currently active thread on the subject from the PM board
http://www.practicalmachinist.com/cg...fx&s=noprofile


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Leigh

[oldtiffie]

Deleted/edited-out

[oldtiffie]

Deleted/edited-out

[cybor462]

oldtiffie... I would never slam Chinese machines. There are both good and bad and if you get the good they work well. I had two new Smithys a mill and a lathe and both were junk. I then bought a new Grizzly lathe and a BP clone mill and they operate flawlessly. I am very happy with both.

Now back to the question, I agree with your assessment and your correction. My BP clone once trammed and I leave the head alone stays trammed for some time. It is wise to check it once in a awhile especially after working it maybe harder than you should.

I actually make a tool (soon to be ready for retail) for tramming. I also use a large angle plate ground on each locating end square and have also used a large square. If the spindle is tight the angle plate is quick and gets you within .001 at least on my mill. The square is a bit trickier and could be out as much as .002.

I do have the nice swirl marks and if using a good endmill (sharp) I do not have a step. Even if I end up with a step from using a semi dull cutter it is out less than .0005 anyway. As I do not do rocket work .0005 is ok. Of course it would not pass the pretty test.

[radish1us]

Original Question

"What is the wuickest and easiest way to tram the head on the a bridgeport mill."

The quickest way to tram a Bridgeport, or Bridgeport type clone, or any mill that has a quill fitted to the milling machine for drilling purposes, with the table being able to be raised and lowered on a knee, is to actually tram the quill.

Yep, try this lot out, lower the quill fully and place a dial indicator on the table and adjust it so that it is touching the quill , at say the 6 oclock position, make sure that the D/I is in the centre of the quill. Then start to raise and lower the table and watch the D/I. Adjust the head until the D/I shows the absolute minimum movement that you can achieve.

Then move the D/I to the 3 oclock position and repeat the manouvers again.

If you dont believe me, try it out, and then just to prove how accurate this method is, out with good ole' plate or whatever you normally tram with and do a double check.

After you have discovered that the head is actually trammed better, than you would of, or could of, done it previously, you will do it this simple easy way from now on.

Try it, before you decide to post any negative replies.

regards to All.

radish

[cybor462]

radish1us... I agree with you 100%. If you read my posts I do it the same way just a different tool. I use an angle plate or square against the quill , check it front and side which gives me the same check as your method. The only problem with this method (using the the outside body of the quill is when it develops play from years of use and abuse my way if you put too much pressure against it with the plate it could deflect the amount of wear and tram wrong. Of course if it has this play it would be a problem while machining anyway. Using a dial Ind would not put any pressure against it so your way might be the better of the two but while my quill is new and tight my way is much quicker. I have double checked my way with the old method (tried and true) and my way gets me where I need to be.
I am sure way gets you there too.
Now since we are both getting somewhere. where are we going?

[Frank Ford]

If your budget allows, you can buy the E-Z Tram (no affiliation, of course).

http://www.eztram.com

I got one a few years ago, and never regretted the purchase. Beautifully made, it really smooths out the process, and works without even taking the vise off the mill table.

Being of retirement age and not retired, I have more $$ than time, so anything that saves a few minutes is always of interest to me. . .

[J.Ramsey]

Frank
I wonder how accurate eztrams "factory seconds" are?