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I use that for all lubrication points on both the Cincinnati mill and my 1937 Southbend lathe.
I have a little manual pump and decant some into a pair of ketchup and mustard bottles whose tips just fit the machine oilers.
Was messing around with the machine and found that I've got about .006" of slant in the table from full stop to full stop could be the table that's got high spots or the way I measured (dial indicator in a drill chuck reading off the table) and I've got about .020" backlash in the x-axis and about .030" in Y the knee is pretty tight at about .002"
A couple thoughts: (if that 6 thou. is in the x direction)
-over that loooong table 6 thou. is not horrendous
-any looseness in the dovetail ways could allow that table to tilt a little under it's own weight due to the overhang, does tightening the table locks change the measurement at each end?
-I am not real familiar with that machine, does it have the ability to rotate the head? maybe it's out of tram?
If you put something flat and smooth on the table you can also do that same test over the y-feed. This measurement will be affected by the "nod" of the head. (......and of course by any table irregularities too!)
Most lead-screw backlash can be worked around by careful planning of feed directions, but it might be worth inspecting the lead-screws and nuts. The lead-screws normally wear most in the middle as that's where they used most.
There are 3 places the 0.006 could be coming from: Knee, Saddle, and Table. Or a combination of all 3 which is the most likely. It is not likely that the table is worn that much, or even that the table ways are worn that much. Consider that the table weighs 100's of pounds and once cranked to it's extremes is is putting a lot of twisting force on everything. When unlocked, my knee ''twists'' about 0.003, measured about 3 inches off to the side of the knee, as the table moves through it's travel. I can see this movement on the DRO reading. My machine is about the same size as yours.
Doing the same test again, start at zero in the center and look at the change as you move the towards the ends. My guess is that the indicator will move positive as you work toward the ends. Then repeat this test with the knee and saddle locked as @brino suggests. You should see less change in the values. Then doing the test after unlocking the saddle and knee one at a time should tell you where the real problem is at.
Once the machine is cleaned up and lubed, then start adjusting gibs on each axis. I'll bet most of that goes away.
0.020 and 0.030 backlash is what I would consider in the range of normal. You always have to approach your work from the same direction to compensate for the backlash, this is standard practice on any machine. The nuts may be adjustable, but don't tighten too much or you will get tight spots.
@brino yes I have tilt and nod adjustment I did a quick circular sweep to make sure the head was trammed and it was pretty good I'll have to try again with the other axes locked. After doing some math it seems alot worse than what I thought it works out to be just shy of .0002" per inch of travel. One of the things I'd like to do is head re-surfacing and my tolerance for that is it has to be flat to within 3thou per 6" length or a total of8thou over the length of the head (18") so by some rough calculations I would be just under 3thou at the 15" mark which is no good for that so I'll have to do some more measuring and figure out if anything needs to be/ can be done thanks guys!
Cast iron that has been neglected and left to rust can look terrible and thought to be BER. In my experience, I have been pleasantly surprised to find out with a little elbow grease the once ugly cast iron can look almost as good as new. Corrosion on carbon steel is a different story. Corrosion on aluminum is a very different story…Dave
Izzy, your machine is in great shape for a machine costing many times what you paid for it! If you could tell us what you were measuring when you got the deviation, it would help with giving advice as to how to resolve the issue, if there is one.
Since there is visible corrosion, I would take the table off the X ways and carefully check and clean them. Dried oil in any of the ways will cause deviations, and some of it will go with lube, but cleaning it out will be easier on the ways. If they are clean, then I'd leave the Y ways alone. If the X ways are cruddy, then the Y ways will need attention too.
This thing was a steal. It's had a very boring life to be sure. In case you hadn't noticed, those funny C shaped marks all over the mating surfaces are the marks from the final scraping in or the surfaces to get them flat. Those marks wear off on a well used machine and to have them present is a really good sign. My advice is the same as the others. Before you get too far into it clean it really well. Start with kerosene or diesel and a 'scotchbright' pad or fine steel wool. That will lift much of the heavier junk. Once it's cleaning up, switch to MEK or Acetone and rags. Be advised, MEK and Acetone are stupid flammable. No heat sources or flames, and for God sake don't smoke around the fumes. Running those fumes through a lit cig,,, bad stuff for your lungs. Now this stuff is a light aromatic solvent. Meaning lots of ventilation is needed if you don't want to REALLY enjoy scrubbing years of hardened way oil from your find.
Now I am not sure what measuring you did. But understand that the table top on a mill gets more abuse than anywhere else, and with the fact this think sat unused for a while, it was probably a catch all surface. Meaning the table surface may be a bit beat up. There are ways of dealing with that. But get things cleaned, then search out a video or two on tramming the head of a mill and do what you see on the video, then take your measurements.
@Dabbler basically I mounted a dial indicator in a drill chuck and checked to make sure my head was trammed before measuring and it was pretty good. I then moved the table all the way out to full stop, put .025" preload on the dial indicator set it to 0 then ran the table to the opposite end I figured this way would just give me an overall totall was this method ok? And how do I go abouts taking the table off?
@Keith Foor I went out and bought some fine stainless steel wool and scrubbed the s*** out of it with some wd-40 and it cleaned up pretty well all the ways have that fish scaling to it still except the knee way you can see the line where the fish scaling stops in the picture. The table is very brown even after the wool I'm gonna go at it with the solvents you mentioned and see where it gets me what are some ways to go about cleaning the table and getting it back to its original shine or is that just not possible anymore? Here is a photo after cleaning and fresh oil!
Firstly let me congratulate you on basically unworn ways - this machine is in great shape! If you were to put an indicator on the Y saddle way and indicate the Z axis way at the discolouration, you would probably find a couple of tenths of deviation where the discolouration occurs... Certainly nothing to be worried about. Your Y ways are in perfect shape. You can view one side of your X ways to check by running the table to each end, photographing the ways from below. I would guess that they are in good shape, except for some corrosion as per the Z ways. The discolouration is very likely due to the machine sitting idle and un-lubed for years, so that condensation collected could erode the z way at the point of contact. No biggie.
A Quick warning: I'd stop using steel wool and move to a stiff plastic brush or a plastic pot scrubber. Firstly, the steel wool cuts the cast iron. This produces micro fine particles that are hard to get rid of and contaminates the oil in your ways. Secondly, steel wool is fairly aggressive and I'd not want to round off any of the flaking (scraping marks) out, because they hold oil, which ensures the life of your ways. Oh - and thirdly, a fiber of the steel wool can fall off, remain unnoticed and get in between the ways, scoring them for posterity.
A way to get rid of the iron oxide is to do spot application of CLR and then rinse and re-lube immediately. Paper wipes, followed by Alcohol and / or WD 40 are helpful in purging the water before rubbing on way lube... It is important to get rid of all the water before coating the ways in oil.
From your description, I'm guessing that you were talking about measuring in X. I would repeat the same indicator check in each of X, Y, and X, and record the results. Now to your problem: What you are seeing is not uncommon in older machines, where the ways in X are worn in the centre of the table. To fix the ways will tale a lot of work, and completely disassembling the components of the X and Y travel [If you have the table off it makes sense to do both.] In the majority of cases, the Z travel isn't far off or worn enough to take the knee off - a very big, heavy job...
You could disassemble the table by following the steps in various Bridgeport maintenance manual (there are a few fiddly bits, and its too long for my memory...) If you are interested in very light use for the moment, why not just lube up , and start to use it, gain confidence, then do a complete rebuild when you have 'more meat in the game'?
(Or, if you don't like I could buy it from you! - Just kidding)
I'll have to re-measure and go from there its probably not as bad as I think from what everyone is telling me its in great shape! There are a few deep scratches in the Y and i guess it just worried me more than it should I'm verry happy with my machine and i really do want to just make chips ill try the clr and see what it gets me I tried running a fine honing stone over a corner of the table top that was brown and it just gunked up the stone :/ I should get myself a straight edge to see how striaght the table is tho maybe I'm measure dirt on the table its very spotty lol lots of brown and a few shiney spots I'd really lile to get a nice shine back on the table
Your table shows that someone, at some time, use it quite a lot. It's condition seems pretty good, however. Several things about not 'gunking' your stone. Saturate it in varsol. Use very VERY light pressure, with long strokes. Relube in varsol every stroke or 2 until most of the colour is gone. Then and only then can you start to use pressure. You will find that your stone is cleaner (and will remain flatter)
You can cut a 1/4 inch groove in the ways and not affect accuracy. (not that you would!) the longs ways average the total of the high spots to produce the accurate movement we associate with these machines. The odd scratch makes no difference.
I've taken an old table on a friend's machine to an oil work machine shop and have the top reground. It cost about 150.00 about 10 years ago. If you have a large flat stone, you could try to hone it, but you'd most likely produce dips and twists in the table. Run an 1/10,000 indicator from your spindle over each of the 4 flats on the table. You shouldn't see much deviation except for the way wear. If it were my machine I'd use my XFine Arkansas stone to take out the high points and dings and use it as-is.
A series 2 Bridgeport is a big machine
And awqured to work at .
They are very heavyduty and a heck of a lot
More ridged than a series 1 Bridgeport.
I would get it cleaned up and running real
Good . Then try to trade down to a Bridgeport series 1 mill.
The Bridgeport series 1 with the J head would
Be a lot more comfortable to run .
If you have room to keep it in your shop
Then fine keep it and get a series 1 also.
Excellent score, it seems. Let's just hope it stays that way. It's impossible to tell just how good a condition it is until you put it in service. Let's hope there isn't something hidden that will take the shine off what appears to be a super deal.
I'm with the clean up first crew. Scotchbrite or steel wool and a mild solvent will make a huge difference in your ability to see what lies hidden. Save the stone work for areas that you can see a good reason for it. If there are no dings to stone down, then so much the better. And things that are difficult to move may well free up once things are clean. I wouldn't try to run it too much until I was satisfied that all moving parts are clean and well lubricated. Then you can give it a more fair evaluation. If nothing major shows up, then you definitely got a steal. Great going and I hope that is how things turn out. But even if you have to spend some on a few bits here and there, it's still overwhelmingly in your favor that you got a good or great deal. Many of us would (and should) be envious.