when you think all problems solved jet 9x20

[casca92]

hanging my sorrowful head, now it seems there may in my no not much opinion,
that I may have a broken tooth in the carriage drive gear ? goes forward a little ways then stalls, then with a tap of a finger starts back to rolling then stall after a little distance. Does not look to intimidating to tear down and inspect ?

what is the consensus of the knowledge pool ?

thank you
for helping the blind to see

 

[pontiac428]

Are the half nuts fully engaged on the lead screw, and is the lead screw engaged with the drive gears?

 

[casca92]

Are the half nuts fully engaged on the lead screw, and is the lead screw engaged with the drive gears?

Are the half nuts fully engaged on the lead screw, and is the lead screw engaged with the drive gears?

yes, sir

 

[TomS]

There is a clutch mechanism that drives the lead screw. It is a spring and ball arrangement. It's been a while since I had my 9x20 but I recall having to readjust the clutch once or twice.

 

[casca92]

There is a clutch mechanism that drives the lead screw. It is a spring and ball arrangement. It's been a while since I had my 9x20 but I recall having to readjust the clutch once or twice.

tell me more, please level of difficulty ?

 

[savarin]

I seem to recall the stop start of the carriage when the threading half nuts were engaged happening on my 9x20.
In my case the half nuts were worn and were engaging and disengaging.
The cure was new half nuts, fabricating a new actuating handle, new dimples for the ball detentes to hold into, re alignment to all the components in the train.
Have a read of these posts as to what I had to do.
They are in no particular order but may give you some ideas.

Stripped Half Nuts

well, not both halves. I cleaned the lathe the other day and made some adjustments oiled etc. When running the lead screw from the tail stock to the head stock with the half nuts closed as if threading I noticed the carriage stopped moving about half way along. It looked as if the half nuts had...

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9x20 stuffup

I'm unsure if it was my fault or the machine. I had two aluminium flanges bolted together on the faceplate with spacers so I could turn the outside dia and bore the inside dia parallel with each other and both end up exactly the same. All was going well on slow auto feed - bore, disengage the...

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9 x 20 half nut problem

I believe I may have a major problem with my lathe (generic 9x20) This is the second time I have had the half nut threads wear away. The first time it happened I hadnt had the lathe long and the problem was swarf collecting inside and preventing the nuts from fully closing. I sorted that out...

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A couple of points - when bolting the apron back onto the saddle make sure you engage the half nuts to keep it aligned with the carriage. Thos two bolts on the top will allow the apron to twist a little placing too much wear on one of the half nuts.
If you have never adjusted the half nut cams in the apron from new I expect they do not engage correctly.
Check out how much swarf in inside the apron, the original shield do not keep it out.
The clutch on mine is not adjustable but doesnt cause any problems.
My latest "problem" was the bolt holding the pulley assembly to the motor came loose and caused all sorts of strange noises.
Good luck.

 

[TomS]

tell me more, please level of difficulty ?

I looked through the Grizzly 9x20 manual on their website and it doesn't show the clutch mechanism. Could be they did away with it on the newer models. My lathe was about a 2010 model. The clutch on mine was on the output of the gearbox and connected to the lead screw. Do you have a manual? Does it show the clutch?