Bridgeport-Repair or Scrap?

Fair warning, I am a “new be” here.
However I have learned quite a bit reading from a lot of folks here.
I have a 30 year old high end import auto repair shop.
I shared that info only so you have some vision of my mechanical abilities.
Hopefully I have been able to post a picture of my BP.
I took a 1911 build class and learned to work with files 5 years back.
I quickly figured out how a mill would help make things easier.
I have Rheumatoid Arthritis which tells me to make things easier on my hands.
So…I contacted my machine shop owner about where to look for a mill.
I contacted his guy and bought what I could afford.
Seldom do I not research what I buy. However I went with a recommendation and here is what I got.



Serial Number J13938
# On end of knee # 25068
Info on Motor;
Master Electric Division
Reliance-Electrical Engineers
Columbus, Indiana

Spindle Speeds;
80/135/210/325
660/1115/1750/2720

173486-LR
Type - RA
Frame - 7420
H.P. ¾
Volts – 230
Cycles – 60
Amps – 6.3
Phase – 1
RPM – 1725
Code – G

6’5” tall, floor to top of motor
Table is 9” x 32”
Y travel is 9”
X travel is 24 ¼”
Base to Table has .007 movements
Table to Knee has .004 movements
Base to Knee has .001 movements

I was told to practice with stock material first but I could not wait and did some dove tail cuts on a new slide.
When the cuts were not correct, I started testing and found the dial for the X was on the Y and vise versa. Fixed that, re-cut and it has been running in competition with out a hiccup, yet. Ugly but runs.
Never the less, I shared that with you to let you know I have learned several lessons with this mill.
I hope I say this correct. I try to make conventional cuts when I can.
Sometimes I need to make a clime cut.
There is a certain point when I am moving table with the clime cut, the bit will grab the project and move it, table and all, in direction table is going, seeming like it just jumped a tooth.
I have .045 backlash on X & Y. Bearing in head is only noisy at hi speed.
Once I tried to drill a ¾” hole in a 2x2x4 block of steel.
After about ¼ depth I could not believe what I was seeing.
With all locks locked except spindle I continued and was convinced the table was moving kind of in a round pattern. Then the proof was in the hole, it was not 3/4.”
I found if I make small cuts to the target size it will work.
With that said, I have learned how to get around a lot of issues with this unit.
However, I need to get rid of these surprises.
I have read quite a bit here on the forum, rebuilding, restoring, etc, Bridgeport’s.
I have heard/read statements “cut your losses and buy a better one”.
I understand that, but there is one characteristic with this mill I really like.
It is small and I can do most of my work sitting in a chair.
That is important due to the fact in am 57 years old, have arthritis and a sciatic nerve that is pissed most of the time that I am standing.
I have been told by tool sales folks I cannot fix it, get a better one.
This info has only been over the phone. I really can’t tell if they want to sell another mill or not.
I am told I cannot get parts for this unit.
I have not been told if the parts can or cannot be made.
I’m thinking the knee, saddle, table mating surfaces would have to be resurfaced and scrapped for proper fit. But those areas remind me of a dovetail cut and I have a little experience in trying to fix something like that, and that worries me.

If you are still with me at this point here is my question.
I am asking this question here because I feel the answer will be short, maybe not sweet, but I am thick skinned.

Are there repair options or is it scrap?
Thank you for your time reading about my issue,
Suggestions, thoughts and/or complaints all welcome.
Michael in Oklahoma.

Michael,
Always repair options. First thing to do is put an indicator on the inside angle of the spindle, where it contacts with the R-8 Collet...measure the runout, by slowly turning the spindle by hand. If it is .001 or less, OK. Then lock down the table (X,Y, Z) in the center of travel, and, placing an indicator to measure deflection from each axis, push against the table and try to get a reading...use a small bar for leverage, if you like. If the deflection is significant...more than a couple of thousand, start manipulating the gibs on the table on each axis, to determine if the movement can be taken up. Also make sure the head is tightly bolted to the machine. Once you have taken these measurements, you will have an idea as to what are your issues, and what can be done about them. For someone to have told you, over the phone, that your problems are unfixable, is bordering on dishonesty, without some testing being done.

Take a look at this video....
1:10 might be like what you are experiencing...

https://www.youtube.com/watch?v=nqQ3HzoSnUc
NO I have zero connection to the maker.

Micheal

Were in Oklahoma are you??
Most of the time old BPs are repairable..
They can be fixed cheaper than replacing them most of the time..
As far as I know parts are available to fix Your machine from High Quality parts or H&W Machine repair
You can purchase them over the internet..
At one time I rebuilt BPs as a side job..

I am in OKC OK feel free to PM Me if You think I can help..
Steve

Thanks for the fast reply folks,
1st, elysianfield, thanks for giving me some hope, I will try your advise and give a report.
2nd, lazz, I have seen that video before but I will watch it again.
3rd, sauerkraut, I'm in Edmond. I will PM you the rest.

This is an earlier Bridgeport but still an easy mill to work on. Parts are available. Do not listen to salesmen.
Google 'Bridgeport parts' gives hits such as:H&W Machine Repair & Rebuilding - Parts and Service for the Metalworking Industry
http://highqualitytoolsinc.com/index.php/store/variablespeedtophousingassembly-15-20hp.aspx
Never climb cut in a Bridgeport. Unless it has ballscrews.
A poorly sharpened drill will cut an oversize hole and push the table around.
Literature: Bridgeport Factory Literature
Lots here, open the BBSsystem as a 'new tab' to search for the pdf to download as one option.
John

Round ram BPs are a bit flexy, a badly sharpened drill larger than about 1/2 will make it move around some. I will be burned at the stake for saying this but you can climb cut on a totally worn out BP, how? Tighten the table lock a bit, just give it a bit of drag, don't over do it. That baby will work a lot better painted grey, man that unit is uuuuugggly!

Yeah, I'm an OSU, Oklahoma State fan, that OU red should be replaced with Orange! Ha!

Hope everyone caught that this is a small, little Bridgeport.
Single phase, 220V, 3/4 horse motor.
The overall size is smaller than normal Bridgeports.
Maybe I should take a picture with me beside it for reference?
And I forgot to mention that when the table is at the north or south end of Y, it binds quite a bit.

silver star said:

Hope everyone caught that this is a small, little Bridgeport.
Single phase, 220V, 3/4 horse motor.
The overall size is smaller than normal Bridgeports.
Maybe I should take a picture with me beside it for reference?
And I forgot to mention that when the table is at the north or south end of Y, it binds quite a bit.

Click to expand...

We all can see that it is a round ram. A lead screw wears more in the center, then some bright spark "adjusts" the nuts. This takes the lash out of the center and will cause a bind at the travel extremes.

A full .001 on the collet runout.
Will work on X, Y, Z travel next.
Here are some pic.

Okay, got some measurements.
1st, Saddle to Table as per video link provided via lazz.
.007

2nd, Knee to Table to get Saddle movement. I did this as the video but I'm thinking we need to subtract table measurement.
The reading is .017. Less the previous measurement it would be .010

3rd, Knee to...Trunk, I guess this is the Z, with a little lift help I got .0025

Michael, Call Mataco in Broadview Heights Ohio. 1-888-785-7810 These people know what a roundram Bridgeport is. Most company's are clueless because it is to old for them. Your Bridgeport is a 1955. Mine is also a 1955. These are great machines. Plus it doesn't look like your machine was beat up. Yes, you can rebuild them. The question is how far do you want to go? The big question is what are you doing with it? Aerospace stuff? Then total rebuild is needed. Just drilling and light milling. Replace what is needed.

Great!
Could you help me with exactly what I have.
1955,
Round ram,
J-head?
Seems there has to be a specific designation to identify the size?

If you decide you need rid of that ugly redheaded step child, I'd be glad to take it off your hands!


P.S. Im in Enid

My small BP is a 48 Round Ram with a later 2j2 Vari speed head 32" table. It is in much better shape than my 70s
model. With a bit of love you can take much of the play out. It needs to be GRAY poor thing is embarassed!! With a machine with a bit of wear lock all axis except the one you are moving. Climb cuts can be done just light cuts for finishing ,no more than .015-020.

moonlight machine said:

Round ram BPs are a bit flexy, a badly sharpened drill larger than about 1/2 will make it move around some. I will be burned at the stake for saying this but you can climb cut on a totally worn out BP, how? Tighten the table lock a bit, just give it a bit of drag, don't over do it. That baby will work a lot better painted grey, man that unit is uuuuugggly!

Click to expand...

I climb cut on my BP, works just fine.


OP, you have a later model round ram machine, made in 1955. This was the transition period from M to J head, before the V ram came out, in fact the V ram was introduced the very next year, in 1956. The V ram was made to better support the much heavier J head, as the round ram double clevis arrangement was too weak. Yours does not have a double clevis, rather a fixed knuckle. Head can not be nodded, not offers much more rigidity. This was most likely a factory unit if my dates are correct. As to the red color, I kinda like it Way better to my sloppy painted '48 round ram M head.

You got a J head on it, so that is good (I mean as opposed to the smaller/lighter spindle/short quill M heads)
3/4 HP is actually plenty if you are not doing production work.
But it will teach you to use sharp cutters, small overhangs and a lot of other good habits.

Tilt the indicator a bit more, and stick it a little further up in the taper. You might just be referencing a burr or ding near the lip (as shown in photo)

The "table tightens at both ends" could also be typical wear in the ways. Long turret mill tables tend to wear more in the middle because that is where idiots park their vise. To even it out a little, put the vise to one side. Then you can do vise work in the vise, and flat work on the other side on the table, or maybe mount a dividing head or rotab, etc without the need to remove the vise, and at the same time, the wear will be better distributed.

All that said, I bet you can do work plenty good enough for small parts for a 1911 or even many much larger projects. Most of the process is learning to use the machine so you lock the axes not in use, turn the handles the correct direction, and if you climb cut, learn how much drab to use based on the size cut. All of us climb cut every now & then even on machines without compensating nuts. But it is hard on a machine in terms of wear. IOW, that drag acting like a brake is also wearing out the ways & gib, like brake pads and rotors wear.

Get some good medium way oil and use it, too.

There's a lot of people on here doing good work on more worn machines. That may or may not suit you, but the issues are exactly the ones you are asking about. 1.) keep developing your understanding of the machine, how it is supposed to work and be set up, and how to optimize the current conditions (such as setting the gibs, etc) & 2.) keep developing your personal skills so you can optimize the performance in each cut based on how you set it up and approach it (DOC, how many passes make sense, speeds and feeds, style of cutter, etc etc). Sometimes this can mean merely learning or adopting patience.

Good luck!

smt

Maybe someone else has covered this, but I didn't see it. In any case, feel free to ignore me. I'm used to it and at times prefer it.

Your 3/4" drilling problems are due to one cutting edge being longer than the other. Locking both axes will help a bit with table movement, as will drilling a pilot hole larger than the point. But resharpening the drill so that both edges are the same length and are cutting at the same depth will also let the table stay where it is. And the drill will cut to size.

I think you you did OK on this machine. If you use it a lot and progress, you'll probably want to move up, branch out, diversify, etc. For now, though, it's a fine machine.

Neil