Bridgeport Series 1 question

[moonlight machine]

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.

Spaces and paragraphs make long posts easier to read.

 

[bigcreek]

jccaclimber:
Bummer its missing the oil pump but now I know how it works thanks to you so I can look for one. I could see the two screw holes and discoleration on the machine where something had been there at one time. Ok thats great Ill look for a pump.
Sorry about the string of pics and questions, very all over the place.
The x handle on the left has a fair bit of backlash it seems but didnt count the thousandths but it probably moved around 6 thousandths or so before engaging.
Ill try pushing/pulling on the end of the table to see how much it moves.
I actually have a good friend I grew up with who lives half an hour away and that is what he has done for an occupation for the last 20+ years is run mills for a couple different machine shops and he is coming over Thursday or Friday to check it out. Most of his work is cnc but he owns a manual mill as well in his own shop. He told me he hasnt been around Bridgeports much but Id think most mills work pretty much the same so it will be good to have him over and see what he has to say about it.

 

[bigcreek]

Spaces and paragraphs make long posts easier to read.

Thanks I will work on that for everyones sanity.

 

[bigcreek]

OK.... now that it has been determined that the oiler pump is missing I looked on Ebay and see the cheapos for around $30. Chinas finest I am sure. Does anyone know if these work well enough to bother using, or should I get a better quality one? Thank you.

 

[M.B. Naegle]

IMO a cheap pump will do fine. As long as you can connect it to the existing lines, the metering and flow of the oil as all handled downstream (provided nothing is plugged or broken). Hopefully the mill didn't see a lot of use without it, but it could just be that someone pulled it to fix another mill.

With the collet key, our mills always had them and I was taught that they are not a positive-stop to keep the collet from spinning when cutting, but to hold it in place while you tighten the collet, since there's really nothing to hold onto past the nose of the spindle. Once the taper makes contact, that's what is going to lock the collet in place. They are also there to locate the collet so they always load and clock in the same orientation, which might matter if the spindle or collet has wear and run-out.

The bolt with the wheel on top of the ram looks like something the last shop put on for something, but there's nothing functional to the mill about it. Tool racks, DRO arms, an lifting eyes get mounted up there often.

6 thousands back-lash is really good IMO. You might get better with new screws and nuts, or near perfect with ball screws, but it isn't nessisary. Always find your position from the same position and they will be accurate. IOW, if you find your postion on the left, then move to drill a hole on the right, then need to drill another hole somewhere back on the left, go past it a little and indicate moving from the left again. A lot of using a mill comes down to how you lay out and find your positions. Often you will find a corner and make that your datum for everything. When I'm using a manual knee mill, often the first thing I will do is sit down with the drawing and determin all my positions from one corner, not center of one hole to edge of another hole, etc.

Have fun with it! Even a worn out BP can make decent parts. Just keep it clean and oiled and most of the rest is all about having rigid set-ups and the right speeds and feeds.

 

[bigcreek]

IMO a cheap pump will do fine. As long as you can connect it to the existing lines, the metering and flow of the oil as all handled downstream (provided nothing is plugged or broken). Hopefully the mill didn't see a lot of use without it, but it could just be that someone pulled it to fix another mill.

With the collet key, our mills always had them and I was taught that they are not a positive-stop to keep the collet from spinning when cutting, but to hold it in place while you tighten the collet, since there's really nothing to hold onto past the nose of the spindle. Once the taper makes contact, that's what is going to lock the collet in place. They are also there to locate the collet so they always load and clock in the same orientation, which might matter if the spindle or collet has wear and run-out.

The bolt with the wheel on top of the ram looks like something the last shop put on for something, but there's nothing functional to the mill about it. Tool racks, DRO arms, an lifting eyes get mounted up there often.

6 thousands back-lash is really good IMO. You might get better with new screws and nuts, or near perfect with ball screws, but it isn't nessisary. Always find your position from the same position and they will be accurate. IOW, if you find your postion on the left, then move to drill a hole on the right, then need to drill another hole somewhere back on the left, go past it a little and indicate moving from the left again. A lot of using a mill comes down to how you lay out and find your positions. Often you will find a corner and make that your datum for everything. When I'm using a manual knee mill, often the first thing I will do is sit down with the drawing and determin all my positions from one corner, not center of one hole to edge of another hole, etc.

Have fun with it! Even a worn out BP can make decent parts. Just keep it clean and oiled and most of the rest is all about having rigid set-ups and the right speeds and feeds.

Great info thank you!

 

[neilho]

And at $1100, you did very well - smokin', in fact :-)

 

[bigcreek]

Ok so another question for you guys. My machine keeps tripping its circuit breaker. It will travel a couple / few inches before tripping. That is using a 3/8" bit and digging anywhere from 1/8" to 1/4" deep at 2" per minute and the bit is going between 600 to 800 rpm. I tried the travel speed faster, I tried it slower, but it trips the breaker regardless of where its running at. Actually the first time it tripped the breaker the spindle stopped moving but unbeknownst to me the power feed kept moving so it broke the 3/8 bit. I heard metal snap and crack and a few pieces went flying and I thoughht I broke something bad on the mill itself but it turned out to be the bit thank goodness. Power feed still works as good as before. I didnt realize it would be that strong. So what are some possible causes for the breaker to be tripping? It is a small button I have to reset on the back of the machine by pushing it in a half inch or so with a screw driver.

I have a breaker in my shops breaker box that has been tripping more and more as of late and an electrician says the breaker is probably just wore out and to replace it. He wasnt concerned at all about any internal wiring causing it to trip. Could it be the same with the machines breaker, just old and wore out and needs replacing? I am certainly (obviously) no electrician I just know what I am told by electricians so ya... I took a look inside the box and not sure how easy or difficult it would be to replace that thing with a new one. I am not worried about replacing it, I am worried about finding the part.

My machinist friend came over tonight and showed me some neat things with how to make sure things like the vise and head are lined up and some of the things on the machine. He said it certainly shouldnt be tripping though with that small a bit but he is no electrician so couldnt help me there. I do have an electrician friend Ill have come over to take a look as to why its tripping but wanted to see if any of you had any ideas. Maybe I found the reason why the government kicked it out of their shop and sold it at auction. (:

Thank you.

 

[Richard King]

Bijur Lubrication Products Breakdown 1

machinerypartsdepot.com

 

[jccaclimber]

I've done some less than honorable and occasionally stupid things with a Bridgeport and never tripped a breaker*. Then again there wasn't a nearby breaker on many of the machines I've used, but that still doesn't sound like normal behavior. I take it that it doesn't happen spinning free, just when in a cut? Less likely with a shallower depth of cut or softer material?

*I do hit over-current shutoff on my VFD with some regularity, but that's because I didn't over-rate the VFD enough for the spindle stop time I want and you can only do so much with a braking resistor.

 

[bigcreek]

Bijur Lubrication Products Breakdown 1

machinerypartsdepot.com

Awesome, thank you.

 

[86turbodsl]

The bridgeport series 1 at work, we bought new 20 years ago, it's got about 15,000 hours on it. It still runs like new. At 6000, you're going to be in great shape, as long as somebody took care of it. Keep it clean, keep it oiled.

 

[M.B. Naegle]

The bridgeport series 1 at work, we bought new 20 years ago, it's got about 15,000 hours on it. It still runs like new. At 6000, you're going to be in great shape, as long as somebody took care of it. Keep it clean, keep it oiled.

Agree'd, but it reminds me of when I bought my first car, 54' Chevy sedan with something like 80,000 miles on it. Lots of rust, neglect, and similar issues, but not a lot of wear. Then my second car, a 53' Chevy sedan, "only" had something like 30,000 miles on the odometer, but the engine had been rebuilt at least once and needed another, the door latch mechanisms were all heavily worn and broken, and lots of other signs of heavy use. The odometers on these cars were only 5 digits, so who knows how many times the 53's odometer clicked over.

 

[86turbodsl]

Like anything, look for clues. On a 53K vs 253K vehicle, you look at the brake pedal. Is it worn down? On a BP, look at the oiling, look at the ways for scraping marks, etc. If you find chips under way guards, you might not have a garage queen...

 

[bigcreek]

When I said it was tripping a breaker I didnt mean the shop breaker, I meant this thing on the back of the mill itself. I texted a pic of it to my friend and he told me it is a magnetic starter. The button I am pointing to with the screw driver will trip about every 5 minutes or so whether it is under load or not. It trips when cutting metal or if I let it run without cutting on anything it will also trip after 5+ minutes. So I need to keep my hand on the on/off switch on the power feed because when it trips and the collet stops spinning the power feed continues moving and that is how I broke that first end mill. But it cuts awesome for the 5+ min until it trips, reset it and Im good for another 5+ min.

My electrician friend is going to take a look at it in the next few days and see if he can figure out why it is tripping. My machinist friend who has done pretty much nothing but run mills for the past 25 or so years for his occupation came over a couple days ago to take a look at my mill. He fiddled with changing the speeds and said it sounded amazing going from high to low and vice versa and said it sounded really good running so that at least was nice to hear.

Is this a normal looking box for the back of a bridgeport mill? Just wondering if it is stock or something added on later. Its looks as old as the mill but who knows. Has anyone else ever had that trip?

Oh and one other thing. I found another draw bar inside that little door that opens up into the cast housing of the mill but this other drawbar is shorter and the hex on top is longer. Too short for a drawbar that would go through the spindle I would think but it looks very similar to the one in the spindle. Any thoughts on what that would be for?

 

[Chrisw]

Was it originally wired for 480 volt? Wired now for 240? If so you need to change the overload heaters for the correct amp draw. (Twice the current draw for 240 vs 480)

 

[Chrisw]

As far as the second Stop/Start buttons.....perhaps a coolant pump?

 

[bigcreek]

The bridgeport series 1 at work, we bought new 20 years ago, it's got about 15,000 hours on it. It still runs like new. At 6000, you're going to be in great shape, as long as somebody took care of it. Keep it clean, keep it oiled.

That is great to hear. There are some old military papers in a p

Was it originally wired for 480 volt? Wired now for 240? If so you need to change the overload heaters for the correct amp draw. (Twice the current draw for 240 vs 480)

it came from a Navy facility, I think the Bremerton Naval ship yard. This is how it looked when I got it from the govt. Set up for 240 volt. I did a test on it yesterday to see how long it would run without tripping and NOT under any load. First time it ran for just over 8 minutes before tripping, then 5 minutes then the next 3 times it was around 3 minutes each.

 

[Brandenberger]

If you look at your picture of the contactor,, the heaters are N20, which looks like about 3.45a max current.

So check the fully loaded amps of your motor when wired at your actual voltage?

looks like 2hp bridgeport motor at 230v would be 5-5.5amps, so it seems you need to change the heaters.

Allen Bradley Heater Elements

electricalmaterials.ca

 

[bigcreek]

That is why I love these forums. Ill swap them out. Thank you!