Bridgeport ways and wear

[inlineParticipant @inline]

Hi,

I have bought a 1980’s series 1 Bridgeport mill which needs some work to get back to a nice working condition.

I have already renovated the vari-speed head and got it running on single phase using a Eaton DE1 motor starter

I am now in the process of stripping the table, saddle and knee off the machine as the knee feels horrible and clucks when lifting and lowering.

Whilst stripping the saddle the slide ways, mainly on the Y axis are quite scored and i think have worn quite badly. Also the oiler was not getting oil to them so glad I stripped it down.

So my question is, should I get the ways between the knee and saddle, saddle and table reground and gibs built back up with turcite or try and scrape it myself?

I am leaning towards getting them reground as once I have bought the equipment for scraping (mainly the measuring and reference surfaces) I may end up being about the same price without the many hours of scraping which I would have to learn as I have no experience in.

I rang a person on ebay advertising machine slideway grinding (josephcornermachinetools) and he said it would be about £900 (not sure if i need to add VAT as I forgot to ask)

Does anybody on here have any advice as this is a new thing to me, used to run machines but never rebuild one. Also if the ways are reground do they need scraping to fit or is that something that they do, Do I flake for oil retention? any advise is appreciated

 

Many thanks, Ian

 

[Pete RimmerParticipant @peterimmer30576]

First question is are they chromed ways? If they are – you ain’t scraping them. TBH if you can afford to have them ground then you should do it and save any heartache. you can cheoose to scrape or flake them afterwards but any rebuilder worth their salt would be able to oil-flake the ways for you as a service.

[inlineParticipant @inline]

No the ways are not chromed. Yeah I thought the answer was probably pay the money and have them ground. Rebuilding without doing something seemed like a bad idea as I would never be quite happy.

So it would be a case of get them ground, reassemble and all should be good.

Do you or anybody have any recommendations of a company to do the work. I live in Macclesfield Cheshire so somewhere relatively nearby would be ideal.

cheers

[David George 1Participant @davidgeorge1]

I have a long time ago refurbished some of the slideways. I would check for wear on the body slides as the one I was working on had wear on both the body and the knee castings vertical way and as these were chromed on the knee these had to be striped ground and scraped for oil retention and then re chromed. Also the saddle to bed was very worn and when traversed allowed the bed to droop a both ends. The bed had to to be ground as well s the cross slide and new gibs were made to allow for the new clearances on both bed an saddle cross gib. There was quite a lot of play in the long traverse screw which was uneven with more wear in the middle so both the leadscrew and adjustable nuts were replaced. the cross slide was not to much wear on the screw but the adjustable nuts were replaced. The total lubrication system has vary drip nipples to allow the lubrication to get to all the ways, slides and screw nuts and as someone had used grease at some time it was easier to strip and replace all parts and pipes with new.

David

 

[inlineParticipant @inline]

I have not checked the body and knee ways yet as it is still assembled. From the bit i can see on the column i can still see the flaking but not looked at the other side as still attached.

The knee to the saddle has terrible wear, i think this is from two things mainly, oil system not working correctly and missing wipers and as its where all the swarf can sit not good at all,  there was also a poorly installed shim on the gib of about 0.4mm.

Surprisingly the table, I can still see the circular grinding marks across the full length, no saying its straight tho I guess. The saddle I can still see the flaking on a large amount of it except at the extreme ends, Which I assume is a normal wear pattern for these machines.

I am hoping the regrinding of knee to saddle and saddle to table will be enough and the gibs built up with turcite.

The X and Y screws and nuts have been replaced before my purchase of the machine with ball screws (I dont know the brand or quality) buy they feel ok in operation.

I have not looked at the screw and nut for the Z axis but will do once stripped off the machine. Nor have i looked into the oiler system yet but will be doing so, not found the misuse of grease instead of oil on the ways but not sure if the correct oil has been used.

Cheers

 

[old martParticipant @oldmart]

Did the quote you got include all the moving parts? If so it is not excessive. You could try local machine shops, they may be able to help.

[inlineParticipant @inline]

Not really sure, I rang to just get a idea of price. We talked about grinding the ways and sorting the gibs out. I need to ring back and have a more detailed conversation I think. Was thinking that I would need to take the three castings (knee, saddle and table) and the two gibs to them and they would sort the grinding and fitting or am I missing something?

[David George 1Participant @davidgeorge1]

I would Adjust the gibs up on the body to the kmee and body and check with a square preferanly a granite or bottle square which will check for excessive wear but remember you have infinate adjustment when you take up setting the spindle to bed with a dial indicator and rotary holder.

David

[Neil LickfoldParticipant @neillickfold44316]

When you do get your machine back together, and use it, remember that they were intended to be lubricated every 2 to 3 hrs. Before use and after every break used to pump the lube handle. Most people don’t , hence the amount of wear.

[inlineParticipant @inline]

Unfortunately I don’t own a granite square and I have not heard of a bottle square, what is one of them?

I will check with the square that i do have which is about 6″ which is about the best I can do. Although don’t think it would make sense at this moment as the ways on the knee which would be the reference surface are worn.

[Pete RimmerParticipant @peterimmer30576]

Where are you? I’m in Kent and I have all those things that you need to do your evaluation.

[inlineParticipant @inline]

That is extremely kind of you but I live in Macclesfield Cheshire which is quite a distance from you. Thank you tho

[inlineParticipant @inline]

I was thinking of a way of checking for square with what i have. If i put a small vice on the knee and clock a parallel up so that it is vertical on the bed. Then spin the vice around 180 degrees and measure it again by clocking it. Half of whatever the reading is on the DTI should tell me how square or not the knee is to the base.

I think this would work and should give me a relatively good measurement, what do you think?

[inlineParticipant @inline]

I guess that the method I have thought of would prove/measure square but not if it is straight. The column could still be worn hollow on the slides

 

[David George 1Participant @davidgeorge1]

This is my Bottle square and a smaller one as well. useful to check squarnes by sitting it on the base and with some engineers blue on a section of the diamier to touch onto the side face and feeler gauges to check any gap. yo can also use it  to clock with a dial indicator on the bed.

 

 

 

David

[inlineParticipant @inline]

looks like a handy bit of kit. Cheers for the info

[duncan webster 1Participant @duncanwebster1]

Braithwaite in Bridlington are the experts at refurbishing Bridgeports, but i suspect it wouldnt be cheap

[Ian Owen NZParticipant @ianowennz]

Personally, I would add turcite to where you remove metal on the slides not the gib.

So the saddle, fits between the knee and the table, if you remove metal on the way that faces the table add turcite there.

If you already have 0.4mm shim on the gib you need to add enough to the saddle so you don’t need the shim and take into account how much is removed from the saddle and the bottom of the table and that is the thickness of turcite you glue to the saddle plus a bit to allow for scraping.

Add turcite to the bottom of the saddle where it slides on the knee and on the knee where it slides against the column.

Scrape the turcite for fit and flake it for oil retention.

 

I wish I had a place nearby that would grind the ways on my bridgeport, (Adcock Shipley varispeed) mine has chrome ways and it looks pretty good on the top of the knee, still see the flaking and at the forward edge it’s a satin finish on the chrome and polished where it has done most of work.

But the bottom of the saddle is full of scrapes and is very worn, I haven’t really check everything to see how worn everything is. I just use it when needed and make allowances to end up with parts within the required spec, which would be easier to do with a bit less freeplay

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