Finally Found One

Well I called Spartan Machinery in Detroit (real good guy to deal with)he said none of the variable speed parts are available new anymore for this model mill. Anywhere. He said see if the guy will take it back and buy a Bridgeport. I'm not gonna do that, I bought it knowing there was problems. I'll try building up the motor shaft and spindle drive hub and recut the keyways. The drive dogs I'll have to live with I guess. If the drive dogs fail later I will put two dowel pins in and put a VFD on the motor. That's my plan, if anybody has any advice let me know. Never welded on s motor shaft before, plan to use a wire feed and do a little at a time I guess. I know heat may be an issue. I can recut the internal key on the pulley with my shaper. I'll keep you posted.
 
Is the spindle drive hub and the spindle pulley hub compatible with any bridgeport parts?
Instead of welding up the motor shaft, I'd turn it down to a standard size and use a single sheave pulley and run it off a VFD.
 
According to Leonard from Spartan..and the guy at HQT, no, the parts aren't compatible. Was thinking of turning the motor shaft down until round, but it would've ended up around 1/2", which is pretty small for a 3hp motor. I'm working on welding it up, one pass at a time so it doesn't get too hot. And yes it's getting a vfd I think
 
Just thought I'd update...the mill is together and working ok. The motor shaft is built back up and keyway is recut. I put a bushing in the sliding half of the motor pulley and keyed it so the variable speed works. The pulley half slides up and down on the motor shaft directly, however, and is only driven by one 5/16 key. Any opinions on this? I am able to grease it. The spindle shaft and hub are built up also
 
Comet/Mighty are still in business. They were kind enough to provide me with manuals on a lathe I acquired not long ago. I can PM you the email address for the guy I dealt with if you need it. Unfortunately, for the parts I needed (taper attachment, complete) they were not able to help me, but they were very cordial. I have run and been around several Comet VMC's and they always seemed to be pretty solid machines. I wouldn't mind having one. I've seen, but not run a manual Comet, but if they are all based on the same quality program, they are pretty decent Taiwanese machines, and many are still in production.

As far as interchangeable parts with original Bridgeports, it's always a gamble, but a fair one. I wish there was a way to know exactly which parts would interchange and which would not. I have an older Taiwanese clone, and it could use a little work, but I am not sure enough to start buying parts which may or may not fit. I can't have the mill down for long. Plus atm, I'm out of commission as far as any shop work goes, including maintenance. I can't even get out to the shop to get on my main CAD machine and do some design work I need to do. I need a ATV/4WD wheelchair LoL!
 
Comet/Mighty are still in business. They were kind enough to provide me with manuals on a lathe I acquired not long ago. I can PM you the email address for the guy I dealt with if you need it. Unfortunately, for the parts I needed (taper attachment, complete) they were not able to help me, but they were very cordial. I have run and been around several Comet VMC's and they always seemed to be pretty solid machines. I wouldn't mind having one. I've seen, but not run a manual Comet, but if they are all based on the same quality program, they are pretty decent Taiwanese machines, and many are still in production.

As far as interchangeable parts with original Bridgeports, it's always a gamble, but a fair one. I wish there was a way to know exactly which parts would interchange and which would not. I have an older Taiwanese clone, and it could use a little work, but I am not sure enough to start buying parts which may or may not fit. I can't have the mill down for long. Plus atm, I'm out of commission as far as any shop work goes, including maintenance. I can't even get out to the shop to get on my main CAD machine and do some design work I need to do. I need a ATV/4WD wheelchair LoL!
Thanks! I didn't realize comet may still be in business. I was thinking of taking some measurements and calling HQT to see if the main spindle drive parts are the same. But if I can get them from comet, even better. It does seem like a well built machine.
 
What you are experiencing is the main reason I have never been crazy about Reeves drive variable speeds. I have yet to see one with many "miles" on it that doesn't rattle up a storm and eventually need major work. Now that VFD's are becoming economical, I wouldn't hesitate to make that conversion. Whatever you do to fix a Reeves, it will wear out again. I've seen it over and over. Not worth it. I would only buy a Reeves drive machine if it were going to get rebuilt to a fixed speed with a VFD on the motor, and priced accordingly.
 
Well that's good to know. I don't have any prior experience with these variable speed drives. I have been looking at vfds, not sure what brand to get, if the cheaper ones are reliable, etc. Also wondering what speed to have the mill run to get the best performance, meaning should I have the pulleys set to run the lowest rpm and over speed the motor? Do you lose torque otherwise? Or do you set it mid range and turn the motor at half speed or less for larger tooling?
 
Any more on this story? I'm seriously looking at the same model comet right now. Guy said the variable speed drive is noisy....
 
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