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Flash319
02-27-2005, 07:30 AM
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
02-27-2005, 07:33 AM
Try the overpriced e-z tram,my home built version works well.

JCHannum
02-27-2005, 08:08 AM
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
02-27-2005, 09:10 AM
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
02-27-2005, 09:45 AM
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
02-27-2005, 11:04 AM
Look here-
http://www.manufacturingcenter.com/dfx/archives/0898/898tram.asp

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

jburstein
02-27-2005, 12:06 PM
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_movments_vert_hd.html#7

-Justin

mochinist
02-27-2005, 12:12 PM
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
02-27-2005, 12:37 PM
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
02-27-2005, 12:47 PM
<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 http://bbs.homeshopmachinist.net//smile.gif 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

aboard_epsilon
02-27-2005, 01:08 PM
John .I've not tried it yet
but I was told that you can put a stack of slips on the quill feed stop doofor .....and then lock the stop with the lock nut ...take the slips out.
then when you advance the quill down it will stop at the precise point you want it to.
Like i said not tried it ...but was told this was the way to do it.
all the best..mark

John Stevenson
02-27-2005, 01:51 PM
Mark,
Lifes too short.
It just seems a glaring oversight that has never been addressed.
You can buy all sorts of Gismo's for the Bridgy but not a precision part.

If you can't quill feed to a thou without jumping thru hoops there isn't much point spending 3 days, 4 hours 35 minutes and 18 seconds getting the head trammed in http://bbs.homeshopmachinist.net//biggrin.gif http://bbs.homeshopmachinist.net//biggrin.gif

John S.

cwhorton
02-27-2005, 02:58 PM
Most BP heads have machined notches on the front next to the "ruler" and along the centerline of the quill that is made for tramming. The blade of a square fits nicely against these 2 "notches", with the head of the square on the table top, of course. Those notches are used to roughly square the head in both directions. It will get you close enough to then stick an indicator in the quill for fine tuning.
The video suggested in the first few posts was ok, but Man!, did you notice the cosine error that guy had on his indicator? I don't think he mentioned locking the knee clamp either.

------------------
Charlie
Eastern Maine, USA

flusen
02-27-2005, 03:02 PM
Flash,

All the suggestions are good. As was said, DO NOT spend the big bucks. For a good tramming device go to your local auto repair center, Goodyear, NAPA parts store, etc. Ask for a discarded break disk. The ones that do not meet specs are discarded. You can probably get it for nothing. Ask them to regrind it using a SLOW feed so you get a good finish. I have every bit of nothing in mine. Got mine from the place I take my vehicles.

Works great with the indicator thingy.

Fred

.RC.
02-27-2005, 03:24 PM
All I do is disassemble part of my magnetic base and stick that in the spindle with the dial gauge on the end of it via a collet and then dial in from there...it takes a while but it works...

Anyway i find getting it perfect a waste of time especially if you are face milling as the flex in the head will always put it out that slight amount when you start milling..

wierdscience
02-27-2005, 03:34 PM
"stay away from the overpriced toys"

Don't buy anything,just build your own.The advantage of the tram monitor is that it monitors the machine while in use.I am going to make one for the mill at work,it needs traming about once a week,should save me ots of time.

bikenut
02-27-2005, 03:34 PM
What they said. Also make sure your machine is level.

Randy
02-27-2005, 08:13 PM
I made this two-dial unit, inspired by an expensive commercial unit.
http://img.photobucket.com/albums/v21/rykrisp/tram-o-matic_2000_5.jpg
It cost me less than $20 for a couple of HF dial indicators. I'm very pleased with it. I find it using very quick and painless compared to the conventional method, especially for straightening up the nod. But I'd suggest that you master the conventional method with a single dial test indicator as well.

mochinist
02-27-2005, 08:20 PM
Okay I am curious, I always use my indicol with a tenth guage to tram in the head. How do you go about using that above setup. It doesn't seem like it would be as accurate as doing it the old fashion way.

charlie coghill
02-27-2005, 08:44 PM
Forrest;
I had about the same question several months ago and you mentioned using the 1-2-3 block. I never got back to ask how you use the block. I have given some thought as to how it would be done, but no lights have come on,no flash in the brain. http://bbs.homeshopmachinist.net//confused.gif

Would you please explain how this would be done.

Thanks
Charlie.
By the way I surly enjoy your articals in the HMS.Keep them comming.

Rich Carlstedt
02-27-2005, 08:52 PM
I believe what Randy does, is adjust the head while watching the dials "come in together". A lot faster than rotating the tram unit.
Nice idea Randy !
What Forrest said is absolutely right, but I would add a few comments as well.
1. make your first adjustments with the quill UP. Then to get more "accuracy", lower the quill all the way down and repeat. This fine tunes the setup and eliminates the .0001 readings.
2. Slighty snug opposite bolts and leave the other two loose while tightening..when you hit the point wanted, BACK OFF the adjusting screw slighty , so that when you tighten the head, it will NOT follow the lead of the helix on the adjusting worm. Many fellows do not understand why the head moves when being tightened..now you know.
3. Once the side to side is done, LEAVE the indicator at the same setting and move it to the front, and adjust for zero there....now only rotate from front to one side as needed, as the zero set on side to side functions with the front as well.
The above procedure can retram a BP head in well under 5 minities
for purists, the last move can be front/back, but the above works fast.

If your really into quick changes, I have seen guys mount dial indicators from the Ram to the head, so when they had to angle mill, they could bring it back to zero using these preset indicators as a "home" position.
Also seen guys tram to deadnuts, and then radially drill/taper ream a hole between the collar/head joint( Below the 0-0 Mark of course)then stick in a taper pin to lock the setting. the nice thing about this, is that if you crash the cutter, you won't move the head as that happens sometimes.
A good machinist always rechecks the tram after a mishap..or risks loosing the job !

Randy
02-27-2005, 10:12 PM
Sorry, I should have included some expanation of the two-dial unit. Rich is correct. As you move the spindle head you watch the dials. One will turn clockwise and the other counterclockwise. When the two dials come to the same reading, the head is straight. It doesn't matter what the absolute reading is, only that both be the same. You can also see immediately if the head shifts (and which way) when you tighten the bolts. The device is self checking. For the initial setup, you raise the table to zero one indicator, then turn the spindle 180* to swap indicator positions, and turn the bezel of the 2nd indicator to zero it. If you handle and store it carefully it holds its adjustment well, and is easy to check if there's any doubt. It may not as accurate as a tenth reading indicator, but I think it's trustworthy to half a thou or better over its span, which is close enough for me.

kap pullen
02-27-2005, 11:18 PM
Charlie,

We always trammed big machines with a single ground block.

Don't have to worry about the accuracy of the new fangled expensive indicating ring.

The block is always the same size if you set it the same way.

Set the indicator zero on the block, rotate the spindle 180, slip the block under the indicator again and see what you get.

You don't have to worry about the indicator banging over those t slots either.

I taper one edge of the block. and re-slide the block under the indicator from that side.

I never saw a pro-machinist, or toolmaker use one of those indicating tools anyway.

I only use the tenth indicator when holding tenths. Time is money after all.

I don't have an hour to tram any machine for a rough job.

Those witness marks, as mentioned, will get you close with a square.

What you put on the floor at the end of the day is what your family gets to eat, Isn't it?

kap

[This message has been edited by kap pullen (edited 02-27-2005).]

[This message has been edited by kap pullen (edited 02-27-2005).]

John Stevenson
02-28-2005, 03:13 AM
<font face="Verdana, Arial" size="2">Originally posted by Rich Carlstedt:

Also seen guys tram to deadnuts, and then radially drill/taper ream a hole between the collar/head joint( Below the 0-0 Mark of course)then stick in a taper pin to lock the setting. the nice thing about this, is that if you crash the cutter, you won't move the head as that happens sometimes.
!</font>

Elliott's and Beaver mills have a 5/8" tapered pin that located the head both ways to set the tram up.
Try knocking that out !!

John S.

John Garner
02-28-2005, 04:42 PM
If I could remember where I got this, I'd provide the appropriate bibliographical credit:

HOW TO QUICKLY TRAM A BRIDGEPORT MILL

Extend the quill a little over 3" and lock it.

Place a 0-1" dial indicator so that it rests against the top of the quill.

Adjust the table to read a preload of 100 thousandths.

Crank the table down exactly 3" using the dial on the crank.

Multiply the reading times 3. (the indicator is now ~9" below the pivot point of the head and you read 1/3 of that)

Adjust the head in the opposite direction the indicator moved by your figured amount.

Check your work by doing it again, it should be dead on.

This works for both directions.


John

quasi
02-28-2005, 05:44 PM
<font face="Verdana, Arial" size="2">Originally posted by John Stevenson:
Elliott's and Beaver mills have a 5/8" tapered pin that located the head both ways to set the tram up.
Try knocking that out !!

John S.

</font>So did a TOS fnk 25 that I had, it took a good man just to crank the head back up after tilting, it had to be 600 lbs!

John Stevenson
02-28-2005, 05:55 PM
<font face="Verdana, Arial" size="2">Originally posted by quasi:
So did a TOS fnk 25 that I had, it took a good man just to crank the head back up after tilting, it had to be 600 lbs!

</font>

Good machines those are. make a Bridgy look and act like a mill drill

elbryant
02-28-2005, 08:00 PM
I was told not to get a machine like this because it cannot be trammed, that is, the head is not adjustable in tilt, only in nod and swing. Whatcha think? Is there some other way to make the adjustment?

http://img.photobucket.com/albums/v226/elbryant/Mill.bmp

[This message has been edited by elbryant (edited 02-28-2005).]

charlie coghill
02-28-2005, 08:22 PM
Kap the light came on and the elevator reached the top floor. Thanks
Charlie

wierdscience
02-28-2005, 08:22 PM
Shims.

One thing about it,once it's in tram on that axis,it can't go out.

wierdscience
02-28-2005, 08:30 PM
I use a 10X10" piece of 3/8" float glass an a co-ax indicator.

Before anybody starts that"nah,nah,nah,float glass ain't flat crap" oh,yes it certainly is..00005" from side to side,ain't no b-port ever been nor ever will be that flat across the tables.And if glass is a fluid,I'm Hubert Humphrey http://bbs.homeshopmachinist.net//biggrin.gif

With a 4-1/2" radius rod stuck in the co-ax I can tram the head in 2 minutes flat while the spindle is turning.

BWS
02-28-2005, 08:41 PM
Framing square on lugs,spot daylight(table's got a touch of sag)making it the same is good enough for 90% of what we do.Closer than that just sweep the vise.