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Bridgeport Series 1 question

bigcreek

Plastic
Joined
Mar 16, 2015
I just bought a Bridgeport series 1 milling machine from the government auction for $1100. Ive bought alot of big equipment from government auctions in the past such as saws, brakes, shears, etc and never been burned yet by getting something that didnt work but you never know what you will get. Well Ive wanted a mill for a long time even though I know nothing about them but I want to learn so this one came up for auction and I bit. I havent put power to it yet because I am currently waiting for a plug to arrive in the mail which I purchased off ebay. Just like all their equipment they let it sit outside in the elements for months on end before finally auctioning it off. Out of all the equipment ive ever bought this one took the elements the hardest. Lots of unpainted surfaces that rust was working on like all the graduation dials/tapes whatever you call them. And the knobs and knurled nuts. However I put evapo rust on them and the rust came right off. The ways werent rusty all thanks to the oil on them. All in all it looks pretty decent now. It has power feed. So here is my question. Now remember I am totally new to mills but I watched some youtube videos and when they put the collet in the chuck they said you had to sometimes rotate the collet around a bit because the collet it slotted and the chuck is keyed. From my research I determined the Bridgeport takes R8 collets. Well I bought some used Hardinge collets off ebay and put one in the chuck and it was a nice tight fit once it got clear up on the chuck, however there is no key in that chuck. There is no slot. I ran my finger around the inside of that chuck and it is smooth as a babys bottom all the way around as far up as I could reach then I pulled out the threaded rod (dare I call it a spindle???) from the top and looked down into it from the top and it looked smooth bore all the way through. Is mine missing something? Or did I just misunderstand about it having a keyed chuck that the collet has to line up with in order to insert the collet into the chuck? The threaded rod (spindle???) does screw into the collet just fine, but again, no key. Thank you
 
I suggest you buy a how to run a Bridgeport or watch you tube shows made by H&W machine as they show maintenance tips. There maybe a Bridgeport manual here in our Books and Manual section too. The "key" in a Bridgeport spindle is a dog point set screw. You find it by moving the quill down out of the headstock about 1 to 2" and hen feel the back of the quill for a taped hole. In the taped hole is a set screw 1/4 / 28 If my memory serves me right. Sometimes the is a thin set screw on the back side of a longer one or on newer machines the used blue thread Loctite so the set screw didn't workout. That sets screw holds a bearing retainer cover on the bottom of the quill Be sure to take out the setscrew ! That bearing retainer cover threads into the quill and you use a spanner wrench to unscrew it. After to remove the cover you will see the spindle that I think your calling the chuck...

On the spindle you will see another drilled and tapped hole, That's where the "dog points set screw collet key is.
Here is the procedure.
 
You do not need that screw / key whatever you want to call it. My Bridgeport has not had one since 1979, no issues used daily in all that time. It is only useful if you are the dufas that runs the drawbar into a collet with swarf in the threads.
 
Thank you for the replies. I was calling the quill the chuck and drawbar the "threaded rod". I have alot of learning to do. Thanks again.
 
The collet alignment key has most likely been sheared off. In most of the rebuilds I do, that is the case and it feels super smooth. It is a good idea to replace it. This cuts down on the possibility of the collet spinning out and ruining the spindle taper.
 
however there is no key in that chuck. There is no slot. I ran my finger around the inside of that chuck and it is smooth as a babys bottom all the way around as far up as I could reach then I pulled out the threaded rod (dare I call it a spindle???) from the top and looked down into it from the top and it looked smooth bore all the way through. Is mine missing something? Or did I just misunderstand about it having a keyed chuck that the collet has to line up with in order to insert the collet into the chuck? The threaded rod (spindle???) does screw into the collet just fine, but again, no key. Thank you
That key is supposed to be the end of a allen screw. Sometimes they shear off or removed.
A new one can be put back from the outside of the spindle piece.
 
The collet alignment key has most likely been sheared off. In most of the rebuilds I do, that is the case and it feels super smooth. It is a good idea to replace it. This cuts down on the possibility of the collet spinning out and ruining the spindle taper.
There is no chance that wimpy little set screw is going to prevent the collet from slipping. When the set screw gets sheared off you stand a chance of the dog point damaging the bore or collet. Tighten it properly and it will not slip.
 
One thing that is missing on my machine I realized today is the manual feed wheel. The small knob is there which I can pull in and out but the hand crank isnt for some reason so Ill have to round one of those up. You know I gotta say I am absolutely amazed at the engineering that went into making this mill. I compare it to my other tools such as saws, brakes, presses, shears, etc and all that stuff is great, but is pretty straight forward. They are nothing compared to this mill in how many different things each tool can do. I cant believe the thought and planning that went into designing these mills. I dont know if you guys ever think about that or if you have been around them for so long your like whatever but they are pretty dang impressive!
 
The hand wheel is usually one of the first things to disappear - reason being it's almost useless. That handle on the right (quill feed handle) is the usual way of making the quill go up and down, cranking the knee up prob 2nd most used (when plunging with a big end mill for example) power feed prob 3rd most (mandatory for boring).

I don't think you'll find the feed wheel useful at all, but if you want one, I'll send you mine if I can find it. It's around here somewhere, haven't used it in 30 years.

Prob the most important thing at the moment is to get more way lube into the ways. If you have a one-shot oiler (prob on the side of the column, lever on top, reservoir of oil visible) pull the lever, wait a bit, pull it again. If you have zerks, you'll need a grease gun with way lube in it.

Whatever you do, DON'T pump grease into the zerks!! All those little oil passages will be clogged and will have to be cleaned out before the way lube will flow again. That's a big job you don't want to do.
 
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Oh ok well I won’t worry about that manual feed wheel then good to know. Ya I watched a YouTube video on a guy cleaning up a newly acquired Bridgeport that had the ports all clogged up with grease and he was blowing them out with something. It has a one shot oiler but I swear I saw a zero on it too. I’ll check. Thanks
 
When someone called me to re-scrape the scored knee ways on a Bridgeport and I saw an air hose hanging on the table. I looked at the owner and said "turn up the pressure, so you have to call me sooner.. Buy a Shop Vac and a brush and use them to clean off the chips, Order a new set of way wipers and ask HW for help as they are the EXPERTS. Just check out all the self help YouTube shows they have.
 
There are right and wrong ways to use an air gun around a machine. Light wave with a broad nozzle from a distance aimed at the vise and you’ll save more time than you cost in way wear. Close up concentrated shots at the way wipers, you might as well be using abrasive paste.
 
In these three pictures I just posted you can see what I believe to be one shot oiling system, however for the life of me I cannot find a reservoir to put the oil into. There is the rubber hose that connects to the bank of fittings which put oil to the ways and I see two screw holes in the housing and a rectangular spot there where something was screwed to it at one time, but IF that was the oil reservoir I do not see where the oil would have plumbed into the line. I even had another guy check it out and he couldnt figure it out either. There are two oil cup places on the head but I dont think all the ways are gravity fed from those two littly tiny oil cups on the head. There are no zirks. Ill post some more pictures. I didnt want to post too many pics at once for fear it wouldnt accept the pics.
 
Here are a couple more pics. One shows a bolt on the top of the head with a large round handle welded to it. Does anyone know what that is for? If I take it out it is a dark hole that goes into the depths of the machine. Might that be the oil reservoir perhaps?? Then a front view of the machine. We got power hooked up to it today and everything works. XY box works, power feed works, forward and reverse on spindle work, rapid traverse works, spindle moves faster and slower when the speed selector is moved, everything works great. There are two start/stop buttons you can see on the front of the machine. The bottom one starts and stops the spindle. The top one does not seem to do anything. You can hear contacts when buttons are pushed but we looked in the box and it didnt seem to be wired up to anything so not sure what its original purpose was for. One odd thing that happened is we wired a plug to it and plugged it in and it burned a wire on a relay in the phase converter. What the heck. I use that phase converter all the time without any problems. So we bypassed the relay in the phase converter and very quickly plugged it in and it tripped the breaker. So we (I say we but my friend is the electrician and was doing all the work) got to poking around and found that the main hot wire running to the transformer for the xy box, someone had taken that wire and put it on the ground connection. It would never have worked that way and obviously didnt so not sure why on earth someone did that. After taking it off ground and wiring it to the correct spot everything worked great. Tomorrow he will get a new relay and throw it in the phase converter so I can properly use the on off switch again. It came with two drawbars. One in the spindle and one inside the housing of the mill. I looked in that little door and it was in there along with a bolt/nut for a vice. Also some paperwork from august of 1959 with a maintenance form of sorts for the machine which was pretty cool. It cost the government I think it said $2450 when purchased new and I paid $1100 for it.
 
And sorry for all the questions guys but here is another one. The crank handle to move the x axis that is located on the left side of the machine moves the table no problem. The crank handle to move the x axis that is located on the right side of the machine spins freely and does not engage so it does not move the table. Is that due to the fact that the power feed motor setup is on that end of the table? Or is something messed up with the handle?
 
And this machine has just over 6000 hours on it. I understand the whole thing of it depends on how it was ran/treated by the operators but is that a ton of hours for a mill of this age, or kind of average? Im into it a little over a thousand bucks and with no prior milling experience so extreme accuracy is not important to me. You guys talk about milling within thousandths but if I am within 64's that is good enough for me lol. Actually starting off Ill be happy if I am within 16ths!
 
1. That is a one shot oiling system, but the pump assembly should be just below the + shaped junction in the first picture. You can see a stain where it used to be. Look at the picture in post #7 here: https://www.practicalmachinist.com/...oiler-lubing-a-bridgeport.296853/post-2454473.
2. No way to know if the rest of the 1 shot system works without hooking it up. Those little metering valves and the hose aren't terribly expensive, but there sure are a lot of them when it comes to replacing them all. 50% chance they'll be clogged and need replacing, but not the end of the world.
3. I've seen machines where you need to rotate the knob (not the handle) to engage the power feed, or maybe something is missing. Others might know more.
4. No idea about the thing with the handle welded on.
5. Your wall of text is killing me.
6. Sounds like there might have been some less than honorable action taken towards the end.
7. At $1100, I think you'll come out just fine, even if you do have to put some $ into it. Read up on here about proper lubrication for each oil point.
8. How much lash is in the handles?
9. Do the gibs need to be adjusted? You can tell by pushing/pulling at the end of the table and seeing if and how much it moves. A little gib adjustment can go a really long way.
10. I take it you don't know anyone local who is good with a Bridgeport?
 








 
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