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New to me Bridgeport Mill

I think we need a picture here.....

Here is the jury rigged quill speed handle...... LOL! It's a #10 machine screw with a piece of paper on it to allow the screw to bite the ID of the setting hole to retain the screw. A #10 nut provided the perfect shoulder. @Mcgyver might be proud of it!

20210629_121034.jpg
 
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Well, I jury rigged the quill feed speed selector system as described above and I hooked up the VFD.

NO GO on the first try. No errors on the VFD though. I just guessed that the motor didn't like the 5hz default speed setting, so I bumped that to 60 and tried again.

Motor spun up nicely, but there was the faint smell of rubber and the spindle wasn't moving. So I shut it down asap.

I can turn the motor by hand, and I can turn the spindle with a socket wrench and a socket clamped into a collet the right size. The spindle does not turn easily though.

I'm still suspicious that the vari-speed spools are messed up. So I removed the speed setting cover and had another look in there. The spindle Spool pulley is set very small which should translate to a high speed, but the window on the dial says low speed.

But hey, the VFD works. I'm running a 3phase motor on single phase power!

Gotta ponder the next step......
 
Ok, I followed the instructions AGAIN that @Brent H provided earlier to try and sync the pulleys with the speed control system. The belt on the front (spindle) pulley didn't move at all, but I believe the rear (motor) pulley must have tightened up somewhat because........ The spindle turns now......

Its not too noisy. Nothing is rattling around or growling. But it's not whisper quiet either. I guess I don't really know what is normal.

I think I will let it run a while. Who knows how long it's been sitting unused. That may loosen things up or it all might go to hell in a hurry. At any rate, I won't leave it run unattended. In the meantime, I'll try to rough tune the VFD a bit more.
 
Still running good......

So I tried low speed too. Also runs good. Seems to like 65 rpm and 550 rpm. Doesn't like increasing either of those speeds. Thinking maybe one of the two spools is stuck. No other good reason I can think of......

I'll prolly play with the VFD a bit before doing anything else.

After that, maybe I should put a tachometer on the spindle to see what it really is. Pretty sure I have two of them around here someplace - one electronic and one mechanical. Neither one has been used in several decades.
 
No tach. Both are gone. I'm guessing one of my three sons has them. It's a definite downside of having a handy family.

Dad's tool supply shop is always short on tools.

But I'm thinking I ought to be able to see 60 rpm with my naked eye.......
 
This will set you up - all the repair video you may require on this site


When I was working on the mills today, I made a little discovery. My Hartford has a small channel ground into the end of the quill shaft. I believe that it was put there by someone to make it easier to access the R8 indexing pin. It works great. No need to pound down the spindle, and no need for ball end Allen wrenches. Just remove the quill cap and then turn the spindle until the pin is visible through the channel. If I end up keeping the Bridgeport, I'll be grinding one of those access channels into the end of the quill shaft.

I doubt dirt would ever be a problem, but if it was then one could always stuff the channel with a wad of Kleenex. The klennex will fall out when the cap is removed and will keep the gap clean when the cap is installed.
 
Another update:

I did a stop watch measurement of rpm. Seems the sheeves will deliver about 40rpm to 70 rpm. No more than that at low speed and the equivalent at high speed.

I tried taking videos with sound but the forum won't accept them.

I can peek in above the speed readout and can plainly watch the front sheeves moving together and apart. But it will only go so fast without complaining. I cannot see what is happening to the rear sheeves, but I suspect that they are stuck. Obviously, something is amiss.

I might try manually compressing and releasing them before I try disassembling the drive system.
 
No wonder some people prefer to buy new.......

I took the bottom cover off to try to tighten and loosen the sheeves and figured it was as good a time as any to have a look to see if I could watch them moving like the front ones. Guess what I found?

The belt isn't even engaged in the sheeves! It's riding on the sheeve compression spring!!! I'm surprised that it ran so quietly.

Now I know why the screws on the front speed indicator cover were reversed.

I guess I gotta take the motor out after all.........

At least the spindle sounds good.
 
That wasn't so bad after all.

It was easy to remove the motor because the belt was off the sheeves.

Getting it back in was not so easy. I had to put a puller on the sheeve to compress the spring. It was obvious that the screws would not reach and even if they did, they don't have enough working length.

After it was compressed, I installed the screws, but working length was still a problem.

We have full range of speed control now, but it is kinda noisy. There are a few speeds where it's really quiet. So maybe I am just being too critical. I really don't know what the system is supposed to sound like.

Anyway, the mill works now. Unless other members have suggestions or recommendations, I don't plan any more fixes until I can get the Hartford working for comparison.
 
I’ll see if I can take a short video of my BP varidrive later today and upload it here (if I can).
 
I took two videos (one low range FWD and one high range FWD), but I can’t upload them. Seems I need to have one of the permitted media accounts - I don’t have any of them.

Maybe there is a work-around?
 
I took two videos (one low range FWD and one high range FWD), but I can’t upload them. Seems I need to have one of the permitted media accounts - I don’t have any of them.

Maybe there is a work-around?

Send them to me. PM sent.
 
I took two videos (one low range FWD and one high range FWD), but I can’t upload them. Seems I need to have one of the permitted media accounts - I don’t have any of them.

Maybe there is a work-around?

Ya, I tried numerous approaches. I assumed the files were simply too big. But I repeated at lower resolution and even tried resizing them - all to no avail. I didn't realize there were any permissions required.
 
Hmm maybe the forum could get a you tube account where it could get uploaded to along with other builds if people are willing to share their projects with enough followers it could be a form of income for the group.
 
Hmm maybe the forum could get a you tube account where it could get uploaded to along with other builds if people are willing to share their projects with enough followers it could be a form of income for the group.

I dunno if youtube would generate any income based on videos like these. But who knows, stranger things are possible. My youngest son and his partner paid their bills during the pandemic with streaming income. So I'll never say never.

I have setup, programmed, and maintained several forums and websites in my day. I'm not familiar with this particular forum, but usually they involve buying a domain (hobbymetalworkers.com in this case), and a hosting package of some kind that runs on a server. It is usually possible to create a file sharing service on the server. That may be what others here have called a "permitted media account". Other services like stores, blogs, databases, etc are also possible. Many hosting companies provide canned packages for implementing such features. They are an obvious way to do what we have been discussing here.

The problem is finding someone the admins trust who knows how to do this and is also willing to donate their time to managing such a service on a timely basis. Speaking as someone who has done this in the past, this no small undertaking and it is also something totally underappreciated by others. A lose-lose so to speak.

I noticed that @architect used a service called "streamable" to post and share a video of his "Bridgeport Project" at the time of purchase. I gave them a once over. They have a free basic service as well as pro and business versions. I'd use them to post a video, but the only videos that I have right now are ones I made before I discovered that the belt was not engaged in the motor spools. I'll try and take a video of the way she runs right now (with VFD) as soon as I get the chance. That may take a while because my bride volunteered me for gaurd duty - my middle son's three boys are here at the farm for a few days......
 
Ok, so I opened an account on the "Streamable" video sharing system that @architect found.

Here are links to three short Videos that I compressed after saving - so they are not huge files. Only the first video used VFD speed control to ramp up the motor. I was cranking the speed dial in the 2nd & 3rd videos. Not so easy to do holding a camera in the other hand.

Low Spd VFD Startup
https://streamable.com/99uzsp

Low speed spooldown
https://streamable.com/t2c0qy

High speed spoolup
https://streamable.com/sho9fk

If they don't work, wait a while. They are taking forever to upload using my slow farm internet access. But I got a link right away to use to share them.

Let me know what you think...... No need to be kind. Adjectives like "total garbage" work just fine for me! I bought these two mills with my eyes wide open: prepared for the worst - hoping for the best.

My own impression goes like this: the spindle feels, looks, and sounds reasonable. The back gear is a bit clattery at times - it also seems very speed sensitive. Some speeds sound like a sewing machine, others sound like big huge gear teeth touching off-the-tooth-ramp a bit.

Also, although I was told (and saw the receipt) that the motor was recently re-wound and had new bearings installed, it sounds a bit noisy too. Thinking it's that nylon key thingy allowing the Spool to move around a bit.
 
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Try this:

BP Vari-Drive low range (60 to 500 rpm)
https://streamable.com/p504tv

and this one:

BP Vari-Drive high range (500 to 4200 to 1000 rpm)
https://streamable.com/pv2rnq


Boy, you are quite the camera wizard! I particularly enjoyed watching your speed dial change.

Yours sounds pretty darn good.

Nice clean machine too!

What I hear in mine that I don't hear in yours is what I think sounds like some gear tooth clatter. But again, I have zero experience.

What did you think of mine?
 
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