Help...lathe auto feed stopped working.

[Papa Charlie]

If it's the driveshaft pin it's #18 on shaft 7. Don't think it's the lead screw pin. Papa, is there an exploded view of the apron available?

It was intended as an example not an absolute.

 

[bill70j]

I know most probably nobody here will have this model lathe,but I thik the basics is the same,so if someone has done this before, please advise me on tackling this job.

Michael:

Same thing happened to my PM-1440GT a couple of weeks ago. Power feed on both the carriage and cross slide stopped working one day.

Pulled off the apron and found that the keyed spur gear that engages with the worm on the feed rod had worked itself off its own shaft. You can see that spur gear which appears cockeyed at the bottom of the photo. The worm and feed rod show just under that gear.

Turns out the OEM had apparently neglected to install the external snap ring that retains the gear on the shaft. Simple fix, bit not very good OEM QC. Maybe something like that has happened to your lathe?



On this lathe, the only challenging repair step was removing the end block that carries the tailstock-end of the feed rod, motor control rod, and lead screw. The block is bolted and double-pinned to the bed casting. But once that was done, the motor control rod and screw came out and I was able to separate the apron -- along with the feed rod -- from the carriage so didn't have to remove the carriage itself. Big mess with draining and refilling the oil, however.

HTH, Bill

 

[Suzuki4evr]

Hi guys. I see a lot of you replied so far, but today I did not have time to help myself by taking pictures for you. I had a lot of milling machine work today and I am pressed for time. This problem comes at a very bad time with the amount of work I have.

 

[Suzuki4evr]

Michael:

Same thing happened to my PM-1440GT a couple of weeks ago. Power feed on both the carriage and cross slide stopped working one day.

Pulled off the apron and found that the keyed spur gear that engages with the worm on the feed rod had worked itself off its own shaft. You can see that spur gear which appears cockeyed at the bottom of the photo. The worm and feed rod show just under that gear.

Turns out the OEM had apparently neglected to install the external snap ring that retains the gear on the shaft. Simple fix, bit not very good OEM QC. Maybe something like that has happened to your lathe?

View attachment 334904

On this lathe, the only challenging repair step was removing the end block that carries the tailstock-end of the feed rod, motor control rod, and lead screw. The block is bolted and double-pinned to the bed casting. But once that was done, the motor control rod and screw came out and I was able to separate the apron -- along with the feed rod -- from the carriage so didn't have to remove the carriage itself. Big mess with draining and refilling the oil, however.

HTH, Bill

Thanks Bill. The takeaway is stripping is inevitable right? But from the replies I got,I have something to work from.

 

[Suzuki4evr]

Papa, is there an exploded view of the apron available?

I will try to give a better pic tomorrow if time alows.

 

[Papa Charlie]

Is shaft turning, if not then it is probably at where I indicated, if the shaft is turning but the carriage actions are not then it is more likely in the area as bill70j indicated in response #12.

Good luck, I hope it is something as simple as a key or roll pin.

 

[Suzuki4evr]

Is shaft turning, if not then it is probably at where I indicated, if the shaft is turning but the carriage actions are not then it is more likely in the area as bill70j indicated in response #12.

Good luck, I hope it is something as simple as a key or roll pin.

I haven't had time for the lathe problem today and doubt if I will even get to it this week, wich is very frustrating,but as I remember the shaft turned, but now I can't recall if it only stopped and go under power feed or only when not under power feed. What bothers me is the amount of play the shaft has where it goes into the apron. Ultimately I think that I must just remove the apron and fix what needs fixing. In any case I think there is a seal there that needs replacing anyway. I must also fix the seal housing at the gearbox where the drive shaft goes into the gearbox,because the seals is rotating inside the housing.

 

[Suzuki4evr]

I got around to dropping the apron yesterday and what I found was what I thought how it worked on my lathe and where the problem was. The problem aria was where the hexagon drive shaft went through a sleeve with a hexagonal part inside and this whole sleeve runs in a bushing. The shaft itself has wear on the corners and the hex on the sleeve isn't perfect anymore. At some points the shaft completely spins in the hex sleeve. That is where the feed that goes and then stops and go again comes from.

I do have another question. On the back end of this sleeve there is a threaded part but I did not remove anything there. My question is could there have been some kind of guide,wich got lost during a previous maintenance operation, with an internal hex to help carry the hexbar, that turns into the sleeve? Can I make a new part like that and use my own head on how that would look like or am I totally wrong here.

The distance from the threaded section up to the hex inter nection is about 1 1/2". The whole sleeve is made out of one piece of material,even the bevel gear on the outside is all part of the sleeve. If I can make a part that threads into the sleeve,do I make a piece as long as the threaded section or must it run a bit further into the sleeve? Do I tighten it up or not completely? Lots of questions guys so please answer as you can.

Thanks everyone.
Michael

 

[Suzuki4evr]

I finally got my new drive sleeve back from the guys who machined the bevel gear and wire cut the hex spline inside. Sorry,didn't take pic of the new part,but you can view the old part in the previous posts. So my machine is up and running again after a month of being out of commission.


I just wanted to show you how full of sludge this apron was,so much that it held back all the oil with the drain plug removed.

What you see here is the sludge holding back the oil. I think this was my fault because of ignorance on how the oil feed for oiling the bed was not separate from the gearbox and I mixed the slide way oil with gear oil.


I had to machine the ends of the hex bar and only had the small lathe to do so. So I made a plan.





I used an old but useable bearing an ground it out a bit so it just fit over the biggest part of the hex and welded it to my work bench. All to save a buck instead of paying someone else.

This was a learning experience and was frustrating at times,but I am glad I did it.

Thanks for viewing.

 

[matthewsx]

I have to do something similar for the lead screw and cross feed rod on my lathe, thanks for the idea