Carriage Stop for G4003G

I leave my kludgy one on the machine with it set to (hopefully) keep the compound out of the way of the chuck.
My major crash awhile back (as mentioned elsewhere too many times) was with the half-nut jamming with insects.
The other close calls that I've had come from 'road noise'.
We live in the country but close to the road and it has a sharp 90° turn. Horns going off, too loud exhausts, and trailers dropping off the pavement.
No matter how hard I try to concentrate, the noise at times, grabs my attention for a second even with ear protection.
Funny how I really didn't notice the road noise when we first looked at this place...
 
Dan,
Has your experience with uncooperative half nuts and insects led you to any particular preventative measures?
Operating the half nuts on my lathe is probably the most stressing part of a job for me even when they are working well. The half nuts are not very accessible and there is no provision in the design for lubrification. Makes it easy for them to be neglected.
 
epanzella said:
The G4003G has no clutch as you probably know but you can't relay on the roll pins to shear before doing damage. I crashed my G4003G into a hard stop about a year ago and a shaft with an integral gear in the apron bent before the roll pin sheared.
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I have been thinking about making a hard stop that has an actuating arm that flips the carriage lever so the carriage quits moving (faster than the motor can shut itself off.) My trouble is that I would want this for both the threading lever (1/2 nut) and for the turning lever. Still thinking.....
 
When not in use I leave my carriage stop all the way to the left against the head stock. By the time the carriage gets to it the tool post would have already crashed into the chuck or even a short collet. That said, I never use it as a hardstop but ONLY use it with a dial indicator on it. Trying to rig up an electrical stop without a solid braking system won't work. When killing the power on my G4003G the machine coasts to a stop advancing the feed anywhere from .020" to .075" depending on the size chuck and the load on the tool. The difference in inertia between an 8 inch chuck and a collet is huge. The feed rate and DOC constantly change the coast down time of the machine as well. Whenever I'm using the stop I kill the power .100" ahead of the finish line and hand feed the rest. This is just for turning, I don't use it at all for threading. When threading I stop the feed in the relief cut or (if on a job with no relief cut) thread away from the shoulder. I saw a video about a sping loaded device to kill the feed but decided against it because if it fails you have a hell of a mess to clean up.
 
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Dan, Insects?? All I can figure is Mud Dauber Wasps???
epanzella, Do you have a link to that video?
Mitch, I would like to follow your thinking.
 
Canyonman44 said:
Dan, Insects?? All I can figure is Mud Dauber Wasps???
epanzella, Do you have a link to that video?
Mitch, I would like to follow your thinking.
Click to expand...
If you mean the video on the auto feed release. No I don't have a link. It was years ago. Sorry. The guy had a rod that attached at the headstock end tripped a spring loaded release at the half nut lever.
 
I stumbled across it today. The one I saw was a DIY but he had to drill and tap his apron. Had a big ole spring on it! But I don't want to drill on my apron very badly!o_O But I also came across an actual Brake for a lathe. He put a plate behind his chuck and then he mounted an actual brake caliper. He had a small lever near the headstock, he would pull and the chuck stopped pronto. Kinda neat.
 
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Google Graham Meek, and dog clutch. If your machine has a reverse tumbler you can fit it with one of these. It's supposed to work well enough to thread into a shoulder no worries, no hands. As the clutch works it interrupts the drive train, but there is only one place for the drive dog to re-engage. So you don't lose alignment with your leadscrew. Not an answer for a lot of our machines here, but a way cool gizmo.
 
I think some times the solutions start to get worse than the problems. When I first got my G4003G the lowest spindle speed (70rpm) seemed waaay too fast for me. I wanted to build a speed reducer but being a greenbean I didn't have the know how. By the time I was good enough to build a speed reducer I was good enough to realize I didn't need one. Problem solved.
 
LEEQ said:
Google Graham Meek, and dog clutch. If your machine has a reverse tumbler you can fit it with one of these. It's supposed to work well enough to thread into a shoulder no worries, no hands. As the clutch works it interrupts the drive train, but there is only one place for the drive dog to re-engage. So you don't lose alignment with your leadscrew. Not an answer for a lot of our machines here, but a way cool gizmo.
Click to expand...
I think I remember that video. Was he the guy threading at 400rpm?
 
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