BP head alignment

[Flash319]

Is there a quick way to realign the head on series one bridgy? Once I turn it to a do some machining it takes forever to get it back square with the table. The 0 mark is not that accurate. What is the proper way to align it? I have tryed many ways but all take a long time.

[IOWOLF]

Try the overpriced e-z tram,my home built version works well.

[JCHannum]

A simple device that will get the head in tram close enough for most work is a large OD pulley or plate 6" or so in diameter. Mount it on a 1/2" diameter shaft and face the assembly in the lathe.

This can be chucked in a collet in the head, and used by setting it on the table to square up the head.

This is basically what the EZ Tram IOWOLF is referring to is. They also make a bridge to span the vise when tramming the head. A waste of money IMHO.

[Forrest Addy]

Tram the tilt first, then the nod. For the tilt you halve the total indicator reading. There will be a ratio between the diameter of your indicator sweep and the distance between the nod axis and the spindle centerline. Work the math to get the correction. Remember your indicator sensing direction so you don't correct in the wrong direction.

Don't get lost on fancy rings and disks. A 1-2-3 block is all you need. I use the bare table if the vise isn't in the way.

Don't forget to snug the column clamp if your bores need to be super square with the table. Mills with some knee wear on them will sag away a bit.

[precisionworks]

Electric motor rebuilders throw away HUGE ball-bearings, and they are free for the asking. I got one 8" diameter, 1 1/2" thick. Remove the inner race & balls & you have a CheepyTram for your indicator point to ride on.

[wierdscience]

Look here-
http://www.manufacturingcenter.com/d...98/898tram.asp

These are a good idea anyway,since B-port mills foriegn and domestic are noodle like in rigidity.

[jburstein]

In case you need to start from the beginning (I don't know from your post if you do or not), here is a useful tutorial thingy:

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

-Justin

[mochinist]

Go with what Forest said, stay away from the overpriced toys. It takes alot of practice to get good at it, and then when you think you're good at it, it will still give you a hard time occasionally.One other thing I will tell you is avoid turning it, I only turn mine if I exhausted all other options.

[John Stevenson]

Most of the British copies of the Bridgeport and I mean the copies not the Bridgies under licence like the Ajax, Elliott and Beaver had real sturdy heads compared to the Bridgy.
Most had from 3 to 7 horse motors and all had either 30INT or 40 INT spindles.
They all also had tapered locking pins that screwed into the head and ram as you were locking up to ensure it went into and more important stayed in tram.

I never understood why Bridgeports never adopted this.

Another point I never understood on Bridgeports was it was suppost to be an all singing all dancing toolroom precision mill as opposed to production but it never had a calibrated quill feed.
OK it had a ruler on the front and a stop graduated in thou's but no way of actually taking the quill down say 3.250" accurately.

People say you use the table feed for that but if you are set over at and angle that feed is useless.

John S.

[This message has been edited by John Stevenson (edited 02-27-2005).]

[3 Phase Lightbulb]

<font face="Verdana, Arial" size="2">Originally posted by Flash319:
Is there a quick way to realign the head on series one bridgy? Once I turn it to a do some machining it takes forever to get it back square with the table. The 0 mark is not that accurate. What is the proper way to align it? I have tryed many ways but all take a long time.</font>

Nope, there is no quick way I spend a good hour tramming my BP head with an indicol(sp?) clamped to the spindle. 1st phase I use a .001 indicator, then when I get it as close as I can, I switch to a .0001 indicator and re-check.. Then I mount my kurt vise back on, and square it back up.

-3Ph