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Stiff quill lever

Mattyboy

Plastic
Joined
Feb 1, 2018
Again continuing from "head swapping"...

Problem no.3
The quill lever is quite stiff to operate, actually have to engage arm muscles to move it down!
Spoke to the guys who had this mill before us (though it has been out of use for over a year and stored in a facilities basement baking under hot pipes) and they said it was always a little stiff.

Any thoughts on what could be causing this? On Bridgeports I've used before the quill lever operates pretty effortlessly.

Thanks, Matt
 
First 2 things I think of are the quill lock dragging or the nuts attaching the head to the swivel not being properly torqued. Supposedly the quill housing is honed with the four nuts torqued properly. any other torque and the housing is not round. In your case you have made mounted it on an adapter? If so is it flat? If not the uneven mounting may pull the quill housing out of round.
Stored near a heat source you would think would keep corrosion out of the guts, maybe they had a steam leak and you have some internal rust?
 
Had a similar issue with one of my mill heads. Auto feed keeped dropping out, hard to move quill.
In the end I found the lubricating grease had gone rock hard.
Cleaned it all out and re lubed it now its 98% right

Funny part is the bloke I brought it off said exactly the same thing "it's always been like that"
 
I had a sticky one that had sat for a while, I pulled the lever all the way down and wiped the quill off, put some lube on it, ran the lever up and down a few times and it was fine after that
 
Tried cleaning and lubricating the quill Sam, felt like it maybe got a little easier but it could be that I got stronger from the workout!

rokbottom: I wondered if the lube may have baked inside there. How do I go about cleaning that out?

Thanks.
 
You should be able to move the quill through complete travel with one finger. Now if you swapped the head from one machine to another I would block up the bottom of the head from the table to support it and then loosen a little and retorque the 4 mounting bolts in a crisscross pattern. As Fred mentions you can check the brass quill locks too but usually if they are dragging it won't be as tight as you mention.

While unusual the spindle splines may cause drag although I would be very surprised if that is the case. If it was just at the top I would say check the nose cone set screw for being too tight. I have had tight quills from people who used the head as an arbor press and cracked the quill pinion, again not too common.

Most of the time I found tight quills was from material that worked in, like cast iron dust and air gun used to clean the machine. As part of a head rebuild we would polish the quill in the lathe with 180 emery then finer. If it was still tight I bolted the bare housing on a steel plate and torqued the 4 bolts to 40 ft/lb and lapped the quill by hand. That solved all issues. Use only light spindle oil. I made a tool out of an old nose cone that works well. If you get to this point use a new skirt and clockspring. We used to get the springs in along and rolled tight by a c clip and install them in the spring housing but I think they are only sold now as an assembly. I worked for a Bpt dealership so our parts came directly from the factory and I drove the 20 minutes there many times. That was 40 years ago and the building is long gone now.

Good luck, you can get that head to be as good as new as long as corrosion isn't the issue. Rust was not typical since these machines were in well kept toolrooms and factories.
 
I'd like to try cleaning the quill first. Is it possible to do this without dismantling, eg a creeping cleaner that i can squirt on? If so where should I apply it.
Havent done the head swap yet, could be that those bolts were over tightened on the adapter as you said Fred, need to get hold of a torque wrench first though.
 
Probably not the issue but if the set screw on the back of the quill is over tightened it will cause the quill to become out of round and drag in the first few inches.
 
You can try something like brake cleaner but it won't get around the whole quill. The best way is to take it apart but give it a shot who knows maybe it will help. I was out in my garage today wiring in my phase convertor for my Bpt, lathe and grinder. I haven't moved the quill on my machine since last April when the machine was moved to my garage. It is as free today as the day I rebuilt it about 28 years ago.
 
Probably not the issue but if the set screw on the back of the quill is over tightened it will cause the quill to become out of round and drag in the first few inches.

That is true, whenever the nose cone is remove mark the spot where the set screw is drilled or spot it with a #7 bit. Tighten the set screw and back it off but make sure it's below the OD of the quill.
 
mines the same way i ll take it out clean it up and seed if that helps. i know im just putting off a rebuild. thats ok tho since im jsut a knife maker and not on the bridgeport 8 hours a day
 
You can clean up the quill without rebuilding the head but you have to remove it from the ram. If I was doing that in the field I would remove the motor, split the top half away from the lower half, support and remove the lower half, take it apart, polish and lap the quill and reassemble. I know that is a very fast outline but that is about what it takes. Probably a couple of hours once you have the tools made up.
 
Probably not the issue but if the set screw on the back of the quill is over tightened it will cause the quill to become out of round and drag in the first few inches.
Exactly what I noticed when I did replace my collet key, and assembled it again. The quill did bind when it was all up. Didn't know what caused it, but found out it was gone when l loosened the screw a little.
So it was actually the quill itself which was deform by the screw to tight? (Out of round)
 
My mill isn't a bridgeport, it's a 1960's Beaver, which is similar in proportions to the BP J head. On that, if any oil on the quill is thicker than Kroil, the quill is hard to move. I've come to the conclusion that the quill should be clean and dry!
 
We are plagued with this at our shop, the only luck we have had is to remove the quill and clean the housing bore.
 
So first thing this morning I removed the quill lock completely and the lever was still still, then checked the back set screw in the quill(which was already loose) no joy on that either. Have sprayed some cleaner on and letting it sit awhile to see if that helps.In the mean time I've posted a new thread with my current intentions. Thanks for all the help.
Matt
 








 
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