A hooligan fit my saddle gib. Anyone in Pittsburgh able to mentor the fix?

Hello, Im in the process of cleaning up a 1980 Bridgeport mill. I just cleaned up the saddle gib and found that it wasnt fit the way it should have been.

It looks like it was ground on with an angle grinder and Im at a loss on what to do about this. I would very much like to try grinding and scrapping it but it will be my first time for both.

Does anyone know someone in the Pittsburgh area that would be willing to mentor me? Im in Franklin Park.

T.J.

Looks like Bill has been at work again :-)

Is it a Bridgeport copy or a real Bridgeport? Asian builders will sometimes a rough a machine in with a grinder, especially ones made in China. Were you having problems with it? Do you know how to use bearing blue and check the "shake"
Milling Machine Maintenance: Adjusting Gibs and Ways - YouTube


If no one steps forward I can help you online I think. Do you have a granite surface plate?
1st check to see if the gib is straight. scroll to minute 5 Richard King scraping class Norway August 214 - YouTube

Richard King said:

Looks like Bill has been at work again :-)

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Clinton? Yahbut.. betcha he plays saxophone better than you and is on-record as teaching skin flute to at least one cuter student than you get for the average scraping class, yah?

It is a real bridgeport. The Saddle/Table gib still looks really good.. just a slight bit of wear around the area where the table lock pushes on it. I bought the mill one month ago and I have not yet had it together enough to make chips. When I bought it I didnt feel the ways tighen up at the ends of travel. And I yanked hard on the table but didnt feel any looseness.

The first thing I did after getting it home was pull the table and the saddle to clean the oil passages. I now have the saddle back on the knee, cleaned the gunk off the gib and saw my problem. I tried installing the gib with but Im not quite sure how tight to make it. Since I dont have the lead screw in, im pushing and pulling by hand. I have not been able to tighten it enough to get rid of the 'shake' that I can feel. Thats when I came up and started researching. I need to split the nuts before I put the screws back in, should I have the done before rechecking the gib? is it a waste of time to try and feel anything by pushing and pulling the saddle?

I have watched videos on scraping but I have never used bearing blue for anything and I cannot think how it would relate to shake.

I do not have a granite surface plate.

The Penguins are playing so I'll get back down there and check for straightness tomorrow.

Thanks for the help

T.J.

Well whatever you do it will be better than what you have.

The guys on here will set you right.

look forward to seeing how you get on.

Tony

thouchin said:

It is a real bridgeport.
.
.
I need to split the nuts before I put the screws back in, should I have the done before rechecking the gib? is it a waste of time to try and feel anything by pushing and pulling the saddle?

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You can waste a LOT of time - money as well - unless you pause first and do more reading, double-check that you understand whatever you read, ask before doing if still not clear. Just not in little tiny drops, one at a time, as with "splitting nuts" when WE haven't any clear sight of where your are starting from. That ain't splitting the nuts. That could actually become "busting your balls", instead?



There's a ton more of Bridgeport-specific rebuilds around than just here in the general rebuilding forum. Good photos, too, over in the Bridgeport & Hardinge forum.

Best to get a wider knowledge base under your hat before you damage something or do some things a harder and more costly way than they need to be done, even have to do them over. More than once is even a possibility. No need to reinvent the wheel on any part of a Bridgeport tune-up. Been done thousands of times, already, not just a few hundred times.

There is more than one Bridgeport-specific professional rebuilder active on PM. They have been kind enough to not keep secrets, but share with others what they do, and how they go about it. That's generous. It is as wise to pay attention to and put to use as found money.

Meanwhile?

Just apply the "six pee" method:

Prior Planning Prevents Piss Poor Performance.

20CW.. inflation, etc.

You might be money ahead by buying a new gib from Basic Machine (Base)

The issue with this is you will have to scrape it to proper taper and mill the notch in, drill oil hole and cut groove on front or back.

Barry shows how to shim a gib, but your gib looks like you need to fix the front side first.
Shimming a Gib - YouTube

There is another way repair you gib . You glue on some Rulon and scrape that gib. If you had a surface plate you could check the gib to see if it was not bent. You could lay it on the table top and see if it is. Follow the method I showed in Norway You tube I posted on top. Then slide the gib is so back of gib is flush with saddle and then slide in a feeler gage or plastic shim stock to find out how much slop or lost motion you have.


If it is .030" you could glue on some Rulon and scrape it by hand. Pretty simple scraping Rulon. but I am so busy now and leave tomorrow to go to Austria. Fixing your gib and you won't have to mill, scrape and drill the new gib. Devitt Machinery in Philadelphia sells Turcite and you could order it from them and glue it using som Loc-tite black max 380 super glue. Glue the dark side. I would order it 1 " longer and wider and after it is dry use a utility knife and trim off the access. You first need to figure out how much shim will fit in the gap behind the gib. You can also check shake or gap with indicator. Got to pack. later Rich

Also for very little money you can pick up a new 18 x 24” granite surface plate and have a very decent reference surface to work on. As Richard said, You would be well ahead of the game if you work with a know surface, when trying to inspect or scrape the gib.

Glenn

thouchin said:

Hello, Im in the process of cleaning up a 1980 Bridgeport mill. I just cleaned up the saddle gib and found that it wasnt fit the way it should have been.

It looks like it was ground on with an angle grinder and Im at a loss on what to do about this. I would very much like to try grinding and scrapping it but it will be my first time for both.

Does anyone know someone in the Pittsburgh area that would be willing to mentor me? Im in Franklin Park.

T.J.

View attachment 241772
View attachment 241773

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Just had a closer look at that. I knew a damned well skilled Farrier, PTHS '63 classmate, who cudda done neater work on an anvil! You know about Pittsburgh, back when steel was still king, yah? Damned nuisance if the rest of the mill is still decent, but it is wot it is.

You'll be wanting to acquire or make a better one even for starting material. Thankfully it IS a Bridgeport, not a clone, so scout about, see what turns up.

I'd not sink any more effort into this gib than mebbe back-shimming it with scrap formica, micarta, PCB phenolic, flashing metal, or brass so it held JUST good enough, long enough to use the mill to blank-out its own NEW gib. You might first see if you can find one usable and affordable.

ANYthing is going to need fitting-up, but it needn't be like trying to salvage the wreck of the Edmund Fitzgerald.

PM/email coming on the goods you'll need to work that part, new, used, or Edmund Fitzgerald, either way!

I'm still scratching my head as to how that ended up like that! From what little is visible in your pics, the mill is in pretty decent shape. But that gib is a freak show!

Good luck,
Wally

Thanks for all the advice. I'm going to take it, back up a little bit and read more about this. I need to acquire some reference tools and take some measurements before I proceed.

I'm not in a big hurry, so I plan to take the path where I learned the most (even if it means the outcome is not perfect). I'll post back when there is something worth posting.

wallyblackburn said:

I'm still scratching my head as to how that ended up like that! From what little is visible in your pics, the mill is in pretty decent shape. But that gib is a freak show!

Good luck,
Wally

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I suspect it actually IS grinder pecker tracks.

Not hand-held angle grinder on clamped-down gib though.
The very reverse. Freehand-manuevered AKA hand-held gib up against a bench-grinder of the sort used for brush hog and rotary mower blades.

Can't see. Done by feel and guesswork.

DAMHIKT



And nooooo King Richard.. don't even THINK about it!

It was NOT on a machine-tool GIB! I've DONE those blades, plenty of them. And a great deal more when a GRINDER was the ONLY "machine tool" we HAD beside a "Waynesburg" coal fire, HALF decent anvil, and a too-damned-sparse selection of hammers!