# Carriage Stop for G4003G



## Canyonman44 (Jan 21, 2020)

I want a Carriage stop to prevent "CRASH".  BION Grizzly themselves only has them for their monster lathes. They recommended calling SHARS. No luck there either. My concern is mauling the ways with some junk. Also if it will slip because it is a Gap Bed lathe. Any advice or sources?
   Canyonman44  aka  Ken


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## mikey (Jan 21, 2020)

If you have a mill, they are simple to make.


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## Canyonman44 (Jan 21, 2020)

Might you know of plans or maybe I could cut a cardboard template.  I have some T6 AL would you think it  would be strong enough?

Ken


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## Canyonman44 (Jan 21, 2020)

PS   That's a cool looking Avatar!


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## middle.road (Jan 21, 2020)

Aluminum will 'slip' - ask me how I know...
I need to re-do mine to add steel to the bottom piece and redesign it so that it is stronger than the clutch.

@raross61 did one up for his  -=- Here -=-


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## mksj (Jan 21, 2020)

Made a few, most recent is posted below, it is an aluminum body but with a steel foot. You need to test it away from the chuck and adjust the feed clutch tension. If you are using the half nut that is a bit different, you will shear the pin. The ones I made were for a 1340GT, but should be very close in size to what you are looking for. There are a number of different ways to build them. They do sell the micrometer stop through QMT that fits there 1236/1340 lathe models.


			https://www.precisionmatthews.com/shop/pm-gt-microstop/
		









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## middle.road (Jan 21, 2020)

mksj said:


> Made a few, most recent is posted below, it is an aluminum body but with a steel foot. You need to test it away from the chuck and adjust the feed clutch tension. If you are using the half nut that is a bit different, you will shear the pin. The ones I made were for a 1340GT, but should be very close in size to what you are looking for. There are a number of different ways to build them. They do sell the micrometer stop through QMT that fits there 1236/1340 lathe models.
> 
> 
> https://www.precisionmatthews.com/shop/pm-gt-microstop/
> ...


That's sharp. Also something else I should try to add, a prox switch to shut it off.
I also need to got wider like yours, but unfortunately on mine the ways end at the head so I had to keep it narrow.


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## mikey (Jan 21, 2020)

middle.road said:


> Aluminum will 'slip' - ask me how I know...
> I need to re-do mine to add steel to the bottom piece and redesign it so that it is stronger than the clutch.






Ken, this one has an aluminum body and steel locking plate that I'm pretty sure will shear a leadscrew pin. I put the saddle up to it and put a lot of pressure on it and it didn't move so I'm pretty confident it will be fine. Works perfectly as a stop for precision turning and boring but I admit we haven't tested it as crash insurance.

It has a spring under each locking stud so you just loosen the studs and you can slip it on and off the rail. The limit screw can be replaced with a micrometer head if desired. 

Works good.


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## Canyonman44 (Jan 21, 2020)

I have been spending some time looking at folks handiwork, which is Excellent BTW, and I think I have found 2 excellent projects. A BallTurner and the carriage stop. 

Thanks for sharing your talents Guys (do we have any Gals?) and Gals!

Ken


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## Canyonman44 (Jan 21, 2020)

Mikey, Nice Stop! Is that a piece of Delrin on the end of the threaded rod?


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## Canyonman44 (Jan 21, 2020)

Nevermind, I followed the Bread Crumbs!


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## middle.road (Jan 21, 2020)

mikey said:


> View attachment 311385
> 
> 
> Ken, this one has an aluminum body and steel locking plate that I'm pretty sure will shear a leadscrew pin. I put the saddle up to it and put a lot of pressure on it and it didn't move so I'm pretty confident it will be fine. Works perfectly as a stop for precision turning and boring but I admit we haven't tested it as crash insurance.
> ...


Any possibility you have the time to post a batch of photos of this design over in _The Projects Area_ section?
Should come in handy for those wanting to do up a stop.


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## mikey (Jan 21, 2020)

middle.road said:


> Any possibility you have the time to post a batch of photos of this design over in _The Projects Area_ section?
> Should come in handy for those wanting to do up a stop.



Hey, Dan. I have an article on it but it needs to be re-written before it's presentable. Short on time right now but it will go on the list, okay?


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## middle.road (Jan 22, 2020)

Cool, another of your neat articles.
There's no rush at all.
I just thought that since it's such a neat design it would be good to have it in a readily available spot instead of buried in all the posts.
As a matter a fact, with all the write ups that you do and the wealth of info contained in them, might I suggest you setup a section over there?
I would be an asset, that's for sure.



mikey said:


> Hey, Dan. I have an article on it but it needs to be re-written before it's presentable. Short on time right now but it will go on the list, okay?


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## mikey (Jan 22, 2020)

Thanks for your kind words, Dan. Not sure anything I do is worth a section of its own but I was thinking of asking @vtcnc /Bryan if I could make a folder to put everything in one place. There are articles I've done that haven't been published on HM and having them in one place would make them easier to find. I'll ask; they might say yes, you never know.


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## darkzero (Jan 22, 2020)

mikey said:


> Thanks for your kind words, Dan. Not sure anything I do is worth a section of its own but I was thinking of asking @vtcnc /Bryan if I could make a folder to put everything in one place. There are articles I've done that haven't been published on HM and having them in one place would make them easier to find. I'll ask; they might say yes, you never know.



Mike, anyone can request to have their own sub-forum for their projects. Just ask & ye shall receive.









						MEMBERS PROJECTS - POST YOUR PROJECTS HERE!
					






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But now that you are a moderator, we have a section for moderator projects.









						MODERATOR PROJECTS
					

Projects and More Projects as done by the Moderator Team (only)




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In case you guys haven't noticed, @mikey is now part of the Staff team. Please congratulate him & go easy on him.... for now anyway, give him some time to get situated, then give him hell!  

(Oops, sorry to the OP for the thread hijack)


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## mikey (Jan 22, 2020)

Hey, wait a minute! Give him hell? I thought all I had to do was sit back and eat popcorn ...


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## darkzero (Jan 22, 2020)

That's just what we tell you to trick you into it! 

J/K of course, we're lucky to have great members here who don't cause trouble.


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## mikey (Jan 22, 2020)

Well, there have been a few ...


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## darkzero (Jan 22, 2020)

Yep, true that. Luckily we don't get too many though & they end up not lasting long here anyway (not always us who show them the door out).


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## Tozguy (Jan 22, 2020)

Mikey, good on you for joining the management team. Management team, good on you for your choice of members. 2020 is looking awesome!


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## Tozguy (Jan 22, 2020)

Canyonman44 said:


> I want a Carriage stop to prevent "CRASH".  BION Grizzly themselves only has them for their monster lathes. They recommended calling SHARS. No luck there either. My concern is mauling the ways with some junk. Also if it will slip because it is a Gap Bed lathe. Any advice or sources?
> Canyonman44  aka  Ken



Whether you crash into the chuck or into a rock solid carriage stop it is still an unwanted crash that will likely cause damage. To prevent crashes why not just have a limit switch on a clamp that is strategically placed to stop the lathe before a crash occurs? This would only be as a backup for a freak lapse of attention at the wrong moment.

However if threading to a shoulder is involved, there are some mechanisms that disengage the half nuts at the right point on every pass. Even so, I find it simpler in this case to run in reverse and thread out from the shoulder with the tool at the back.

A solid clamp on the ways (with or without a micro adjustment) is best used for limiting movement of the carriage by hand so you can feel it stop without crashing it.


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## Canyonman44 (Jan 22, 2020)

Congrats! Do I have to call you SIR now?


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## mikey (Jan 22, 2020)

Thanks, Ken and Mike. I expect that nothing will change on my part except that if I see somebody being disrespectful to one of our members, I can do something about it.


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## macardoso (Jan 22, 2020)

You could add a switch to your stop that would be wired in series with the machine ESTOP. This way hitting the stop would turn off the machine.


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## middle.road (Jan 22, 2020)

Tozguy said:


> Whether you crash into the chuck or into a rock solid carriage stop it is still an unwanted crash that will likely cause damage. To prevent crashes why not just have a limit switch on a clamp that is strategically placed to stop the lathe before a crash occurs? This would only be as a backup for a freak lapse of attention at the wrong moment.
> 
> However if threading to a shoulder is involved, there are some mechanisms that disengage the half nuts at the right point on every pass. Even so, I find it simpler in this case to run in reverse and thread out from the shoulder with the tool at the back.
> 
> A solid clamp on the ways (with or without a micro adjustment) is best used for limiting movement of the carriage by hand so you can feel it stop without crashing it.


I agree with with your comments - mostly. The exception is a lathe that's designed like mine.
It could really use a brake and a prox switch modification.
Even with the power cut off it would have continued to spin to a stop.
Here's my crash - the half-nuts had jammed and I couldn't get them disengaged quick enough:








						Goofs & Blunders You Should Avoid.
					

Yes, what could go wrong, please don't tell me this happened in a civilised country. I did notice some kind of Chinese ideographs on the lower forklift near the end of the video.




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My thinking in retrospect was that if my poorly designed carriage stop had worked, just the shear pin on the clutch would have need repair.
As it was I didn't find out until later on that the spring pin in the clutch had mangled and seized solid. So it wouldn't have functioned properly anyway.
Perfect storm.


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## Chewy (Jan 22, 2020)

here are a couple of ideas. https://thecogwheel.net/2019/04/04/carriage-stop/








						Micrometer Carriage Stop
					






					tomstechniques.com
				




I have the one that comes with my lathe.  It is steel and I use it for a hard stop to keep from crashing.  I wish to make an adjustable one.  I am leaning towards the Cogwheel version and also to make it that it will handle a 2" indicator with positive stop in both directions so I can use it left or right.

With the one in the first link that *mksj *posted, it should not be too hard to wire the switch shown to a relay to stop the lathe.


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## Superburban (Jan 22, 2020)

I saw a cool setup on a 4003G, that mounted on the rod that activates the switch, and another piece mounted at the head end such that when the carriage contacted the non movable part, it forced the power lever to the off position. I thought I saved some pics, but cannot find them now. 

I also found out by accident that if you do not have the banjo for the change gears real tight, the gears will push each other out of engagement if the carriage gets blocked.


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## Canyonman44 (Jan 22, 2020)

Hi Mike,  We were talking somewhere about a jig a guy made to cut repeatable way cuts.  I'm kinda paddling in the deep end, but I think it's



			https://www.hobby-machinist.com/gallery/cutting-45-degree-for-ways.94233/full?d=1467204966
		


Ken


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## hman (Jan 22, 2020)

Canyonman -
If your lathe uses a VFD (or contactors that use a low voltage/low current signals) to control the motor, you might be able to rig up a carriage stop with a switch.  

I originally posted on my (hard) carriage stop on 








						Carriage Stop
					

A couple of recent projects on my lathe made me aware that really I needed a carriage stop of some kind.  I had an old one made for another lathe (no idea where or when I got it), but it wouldn't fit my 12x24.  I measured the lathe ways and designed a new stop body that would re-use the already...




					www.hobby-machinist.com
				




Last year I added a microswitch.  I'm pretty sure I posted about that modification somewhere on the forum, but I've not been able to find it.  So here are a couple of photos to give you an idea.  The microswitch opens the "run while closed" VFD circuit when the carriage depresses the plunger.  Note that the switch is activated by the side of the plunger as it moves inward.  This allows some overtravel without crunching the switch, as might be the case if the switch were located at the end of the plunger.  I have a braking resistor on the VFD, so the spindle stops pretty quickly (about ¼ turn at 100 RPM).  The ¼" phone plug goes into a "shorting" type jack, so that when the plug is removed, the "run" signal maintains continuity.  When I bought the phone plug and jack I added a dust cover to my order.  Note that it's a "stereo" phone plug.  That's because the signals going to the VFD need to be isolated from ground.  Because it's mounted to the metal casing of the lathe, the outer shell of the jack is grounded.  The switch is connected to the tip and the first ring of the plug.

All you have to remember when using such a switch is to set the reverse/stop/forward switch to "stop" before moving the carriage away.


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## mikey (Jan 22, 2020)

I have to ask. Do you guys always leave your carriage stop on the lathe? Do you use it as crash insurance?

Mine sits in a drawer until I need to turn or bore to a precise point. It is used as a soft reference even then; I don't ram the carriage into it, ever. I don't leave my carriage running in power feed without me being totally focused on the cut so in a sense, I am my own crash insurance. 

Just curious about this.


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## Nigel123 (Jan 22, 2020)

I am the same way only use it for precise machining and hand feed it the last 100 thous


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## hman (Jan 22, 2020)

I can park my stop at the far left end of the ways, where the carriage never goes. So I generally leave it on the lathe in that position.  

I can also use it as a hard stop by unplugging it.


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## Canyonman44 (Jan 22, 2020)

Superburban, did you manage to find that info? Has anyone with a G4003G wired in a switch?  I had the lever stop on an old lathe I had.  Mine has a foot lever you must stand on to make it go.


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## Canyonman44 (Jan 22, 2020)

hman, No VFD but thank you for the info

Ken


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## epanzella (Feb 1, 2020)

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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## Canyonman44 (Feb 1, 2020)

Ouch!!! What did the repair set you back??? [if you don't mind me askin]


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## epanzella (Feb 1, 2020)

Canyonman44 said:


> Ouch!!! What did the repair set you back??? [if you don't mind me askin]


Money wise it wasn't too bad. About $30 for the parts I think. I provided the labor. The apron had to come off and be about half disassembled. The hassle was that another gear had to go on that shaft and the new part doesn't come with the hole drilled for the pin. Grizzly said to assemble it and drill the hole in place but there was no way I could get a drill in there. I took some careful measurements (about 3 times) and then rigged up a fixture to drill the hole. (see pic) I had never even seen the inside of an apron before but it came out good.


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## Superburban (Feb 1, 2020)

When I crashed mine (I set the boring bar on the chip pan, and it wedged between the apron, and the headstock), I was lucky that the banjo was not real tight, and the gears pushed enough to move the banjo, and disengage the gears.


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## Canyonman44 (Feb 1, 2020)

It's a shame that you can't guarantee that reaction.  Maybe a torque setting that could be used. Or a spring/bolt type fitting.
Things that make you go  Hmmmmmmm?
epanzella, Great Pic BTW
Ken


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## middle.road (Feb 2, 2020)

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...


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## Tozguy (Feb 2, 2020)

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.


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## Mitch Alsup (Feb 2, 2020)

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.



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.....


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## epanzella (Feb 2, 2020)

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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## Canyonman44 (Feb 2, 2020)

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.


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## epanzella (Feb 2, 2020)

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.


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.


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## Canyonman44 (Feb 3, 2020)

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!    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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## LEEQ (Feb 3, 2020)

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.


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## epanzella (Feb 3, 2020)

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.


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## epanzella (Feb 3, 2020)

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.


I think I remember that video. Was he the guy threading at 400rpm?


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## LEEQ (Feb 3, 2020)

I never saw a video. The author was kind enough to send me prints for the mini lathe. I had to figure it out from there. That was a good brain teaser. I now have a book of his that details a version for a Myford lathe(I think), and how the system works. Fitting it to your machine is the main difference between models. There are several other projects in there.  Very nice tools to make in the home shop.


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## LEEQ (Feb 3, 2020)

ok, youtube search GadgetBuilder dog clutch. Looks like he has a video. not sure if its the same, but has to be close, right? Heck I think there was a guy here that fit one to his grizzly, I think a go602. Jim Something if memory serves. Maybe it's still around. I have an awful time with the search here. Now I mostly cheat with google thanks to some good advice. I search for what I want and also put in hobby machinist so a lot of the results are from here.


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## Canyonman44 (Feb 4, 2020)

If you scroll forward on YouTube there is a video of dog clutch threading on a mini mill. THAT'S THE WAY I ENVISIONED IT WORKING!!!!!!!!!!!


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## LEEQ (Feb 4, 2020)

did ya maybe mean mini lathe? If so check out the stuff mentioned above. Keeping in mind it works with lathes that shift into reverse like a 7x lathe.Another  author would be something like Martin Cleeve. The title is something like screwcutting on the lathe. I believe that was published prior to Mr. Meeks efforts, and describes the same type of device.


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## Canyonman44 (Feb 4, 2020)

Yea, mini lathe. You got me.


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## jcmullis2 (Apr 28, 2021)

Did the OP ever get a carriage stop or maybe some direction one? I’d like to have one also. Even one that disengages the forward reverse lever.


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