Help! Back Gear suddenly froze

hi all,

well I'm just making cuts with my 1947 heavy 10R (small spindle ID version), in back gear, and all of a sudden after about 45 mins, it all stopped.

The back gear pin seems to be out and wont go back in. The spindle is locked as if the pin was in. Spindle turns the chuck freely.

I'm thinking the back gear had some kind of seizure or failure.

I don't want to make anything worse so figured I'd run it by there before doing anything or taking things apart.

Thanks

If you disengage back gear, and pin in bull gear is disengaged, does it all spin by hand, or what's it do. I'd drop the cover off gear side, check forward, reverse, neutral and such by hand to see what does what. Just checking gear lash by hand in everything may reveal something.

That happened to me once after I had added the special grease into the oil hole .
I was able to flush it out with light oil and get it moving again
Have been oiling religiously every time before engaging back gear .

OK I should have said "bull gear". I didnt know the nomenclature enough. The bull gear, spindle, and chuck are frozen together as one, regardless of the bull gear pin. I'm thinking there was a lack of lubrication and it froze (I had tried to oil it, didnt accept any, assumed it was full) . The question is "now what"

WAIT! You posted while I was typing... The bull gear is keyed to the spindle! The bull gear, spindle and chuck ALWAYS turn together.


If there is grease between the cone pulley and the spindle it will bind up sure!

Don't force anything but take the back gear and shaft out. That gives you some room. Loosen the spindle take up nut a turn or two. Remove the lube hole plug and see what you can. With the hole up, force some solvent, like mineral spirits/paint thinner, into that hole. Oh, put a bunch of rags under the head stock 'cause this is very drippy!

Now try to work the spindle in the pulley. If it won't move, just make sure it's full of solvent and let it sit over night. Keep trying to move it. If it doesn't surrender in a couple of days then it's time to get tough.

Put one of your chucks on the spindle, and put a strong stick side-ways across the jaws. Stick wants to be long enough to come up solid against something solid when the spindle is rotated in the reversed direction.

I assume you've disconnected the power......

Now get a big strap wrench with a web wide enough to cover a pulley step. Put this strap wrench on the big pulley step so the wrench will work turning the spindle in reverse.

Apply force. At some point this thing will start moving. Move it some but don't use a 4' cheater. Just move it and add solvent as necessary, rinse and repeat.

I've had to do this twice now, not on my machine, and the procedure works!

Good luck,
Pete

hi pete, I did that and.. it worked. I put PB Blaster penetrant in the oil hole and freed the spindle. I think now that it was run dry, and wouldnt accept oil because there was debris under the oil hole or maybe dried oil.

Now its free again, thank you.

I assume I need to get the PB out of there and put the proper lubricant in there. Would that be spindle oil or something else? I know I can search for that but may as well ask here.

And do you suppose there's any damage ? Is sounds and feels fairly smooth. I'm not big on removing the spindle and disassembling unless I have to...

Good news!! That certainly does sound like it was dry. I use Mobile DTE 26 Hydraulic Oil, Heavy Medium, ISO 68 in the cone pulley as well as everything else on the lathe except the spindle and ways.

The only thing to do is fill it with oil and rotate it by hand a few time feeling for binds or roughness. If it is rough or binding then disassembly is the only thing. The rough spots must be removed carefully and finished smoothly. Only the high spots need to go, the low spots will hold oil...

Pete

and what if I feel slight areas of resistance when turning the chuck while holding the cone gear, which I do. its not a lot but def not equally smooth all the way around...

also, what surfaces are involved here, the steel spindle I assume and is there a bearing surface inside the cone gear like brass or something? I'm just wondering what stuck to what, and if any material would have heat transferred...

Just keep squirting the oil like Pete said....DTE26 and it won't happen again.

Every time you go to use back gear give it a little.

Get some ATF and squirt some in.

Let soak over night then add more while holding cone and turning chuck.

Blow it out with compressed air then oil it again with atf.

Add as you do this and let it soak overnight.

Do this a few times then oil ot with proper oil every time you use back gear.

Why ATF ?

It is very high detergent and will clean things well while lubricating.

It will help clean out the area of dried up stuff without pulling apart.

Sent from my SAMSUNG-SGH-I337Z using Tapatalk

Yep, what Tony just said is a better program 'cause it'll wash out the junk better.

Pete