Just got my J head - things to do? and parts?

Dynahoe Dave

Dynahoe Dave

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I got it moved, almost moved into it's permanent location. Since I had to remove the handles, power feed, and lead screw for the table, is there anything I should do / check while it's partially apart? Clean out the old grease? Check the lead screw nut for wear? Are replacements available, or are they stupid expensive? Upgrade-able from the kind that bend to the split ones for the backlash adjustment?

Change the oil in the head?

Also, curious about getting [or un bending] the handle for the leadscrew that moves the table forward and back. It must hace taken a hit in the past, as it's bent.
 
Congratulations !

A clean up is always a good thing.

New nuts are not terribly expensive. https://www.ebay.com/sch/i.html?_from=R40&_trksid=m570.l1313&_nkw=bridgeport+lead+screw+nut&_sacat=0

You can't really check the backlash until you reassemble the machine.

There is no oil in the head to change. Everything that needs lubrication is greased, or oiled from the oil cups on the head. Normally no service is required until a teardown for bearing replacement in the drive system.

You may be able to straighten the handle or it may just break when you try it. Don't try to straighten it on the machine, you might damage the lead screw. With a bent handle, my concern would be a bent lead screw. Replacements are available. https://www.ebay.com/sch/i.html?_od...70.l1313&_nkw=bridgeport+feed+handle&_sacat=0
 
If you need parts and advise on what to inspect as well as on how to install them I would contact these people:
https://www.machinerypartsdepot.com/

They are excellent people to deal with. They are more than happy to assist you in any way they can, as well as guide you through inspecting and replacing parts. I have done business with them going on 20 years. They have everything you'll need at extremely reasonable prices
 
You mentioned cleaning out the old grease... are you talking about the table/knee/saddle ways? If your machine has Zert fittings, these are not meant to be greased. They are for pressure oil guns. Way oil is to be used. If you have grease in yours I would clean them out and get/make an oiler.

Ted
 
I recently did all this. :) Take it apart, clean it up real thoroughly, lube properly and re-assemble. Unless there is a good reason, don't mess with the spindle. Do a simple runout test with a test indicator and if it's decent, leave it be.

As mentioned, if there is grease on the ways and/or in the fittings, clean it out and start over. It takes some time to get it all out, but it's worth it. I used brake cleaner with the straw and pipe cleaners to purge the grease out of all the little passages.

I didn't have much luck with the push-on oiler. It just didn't seal up well on some of the fittings. Perhaps it works better on the "official" fittings. I modified a grease gun from home depot which works far better for me. A couple pumps on each fitting once in a while and things run nice and smooth.

I didn't have a bent handle, but if I did I would remove it and use a press to try to straighten it. Replace if that fails. Then check the leadscrew to make sure it wasn't damaged.

If the nuts are in decent shape you can split them yourself, cut along the existing line, clean up on a lathe or perhaps with a file. I did this and got backlash way down.

I disassembled everything, soaked in purple power and scrubbed to remove grease, oil, dirt, etc.. Then soak in evaporust to clean off surface rusting. Then oil with way oil to prevent further rusting. Replaced the belts and felt wipers with new units, along with various fasteners with stripped or questionable heads, and a few cosmetic replacements.
 
The bent handle seems to be it - the shaft shows no visible sign of wobble, or binding, etc. that I would expect if the leadscrew was damaged also, so I think that's ok.

So the Zerks are for oil, ok. Ill look into that. I automatically thought grease, because Zerks. I have no idea what was used before I got it. There is grease on the lead screw, or very dirty goopy oil.

I need to fix up the wiring , it's a weird mix of pro looking and hacky.

I have to see if I can find a good diagram of how it should be wired with a phase converter, reversing switch, etc.
 
Figured out the wring. The motor was modified for use with a H A S phase converter. I still have to do something to fix the insulation on the older motor wires - the insulation is crumbling off of them! It's a good thing I took that cover off...
 
How to wire it depends on the type of phase converter you use. A VFD needs to be wired direct to the motor. A static or rotary converter can be wired through a reversing switch. My wiring was getting pretty brittle as well, I replaced all of it with some cable from the local home improvement stores. Just sized it properly for the amp load, with a little extra as they had a remnant cheaply available. If it's the motor leads, I think I'd clean them up as much as possible and use heat shrink on them. That might require opening the motor to get to all of it. Thankfully, mine didn't have that issue.

Mine also came with a switch and fuse box assembly on the back of the column. I just removed that as overcurrent protection is handled by a dedicated circuit breaker and the VFDs. Same with switching, as if I used it on the 3 phase side I could blow the VFD if it got bumped. If I were using a static/rotary converter, I would have used it and used it as a junction box for the power feed wiring as mine uses the old gearbox feed.

It's pretty common to get these from people with grease in the zerks, as they are normally used for grease everywhere else. Even if yours doesn't have grease in there, it sounds like it needs a through cleaning anyway. Be sure to clean out the oil passage in the feed nut carrier. Mine was packed full of grease/dirt/chips. Almost couldn't tell it was there.
 
Yes, the brittle wiring is the leads on the motor. Getting set to fix that.
What does a GOOD VFD cost? 1HP flat style / pancake motor.
Feed nut carrier? Where is that?
Contacted HW machine, got some part numbers to order, way oil, etc.
 
Feed nut carrier is #18 here.

https://www.machinerypartsdepot.com/store/1478157/page/549798

Define "Good VFD". Mine cost about $70/ea with a coupon on ebay. They work great for me. I own 3 now. Belt grinder, and 2 for the Bridgeport. Mine are rated for 2HP, but that's mostly because that was the best deal at the time. They are overkill for the main 1HP motor and way more than needed for the 1/8HP power feed. But I can swap them between machines if needed.
 
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