# Quick Carriage stop



## markknx (Apr 4, 2013)

I almos finished this today I just want to change the stop bolt. the socket cap is just a temp thing. After crashing compound the chuck a few weaks back it was time I did this.


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## fretsman (Apr 4, 2013)

Looks real nice, and yes, these are a must have accessory for sure.

Dave


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## tigtorch (Apr 4, 2013)

Please forgive a stupid question but how does this work?  It would seem to me the right way to do it would involve an e-stop switch.  I am obviously needing to learn more on this because I need one too.


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## righto88 (Apr 4, 2013)

Looks very nice and will work very well. The next thing I will make for my old sheldon lathe is one!


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## Ray C (Apr 4, 2013)

Very nice.  Good job!


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## PurpLev (Apr 4, 2013)

Very nice! I like the release mechanism.



tigtorch said:


> Please forgive a stupid question but how does this work?  It would seem to me the right way to do it would involve an e-stop switch.  I am obviously needing to learn more on this because I need one too.



not a stupid question at all - this is a manual stop. not intended for power feed so no e-stop switch required. the way it works is you power feed the carriage. when the carriage is close enough to the end of it's travel (for the particular cut) and is nearing contact with the stop you disengage power feed, and finish the cut by hand - in which case you turn the carriage until it hits the stop.


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## tigtorch (Apr 4, 2013)

The reason for my stupid question arose from me threading an 8 tpi internal thread the other day.  Even in back gear at 50 rpm with a low thread count the carriage moves quickly and you have to be very quick on the halfnut to avoid hitting something.  I guess this stop was not intended to address that situation.

It would seem that it wouldn't be too hard to design an adjustable stop with an e-stop switch mounted on a spring loaded probe that allows enough travel to adequately stop the lathe in back gear.  Has anyone ever heard of something like this or done it themselves?


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## PurpLev (Apr 4, 2013)

tigtorch said:


> The reason for my stupid question arose from me threading an 8 tpi internal thread the other day.  Even in back gear at 50 rpm with a low thread count the carriage moves quickly and you have to be very quick on the halfnut to avoid hitting something.  I guess this stop was not intended to address that situation.
> 
> It would seem that it wouldn't be too hard to design an adjustable stop with an e-stop switch mounted on a spring loaded probe that allows enough travel to adequately stop the lathe in back gear.  Has anyone ever heard of something like this or done it themselves?



an e-stop can be included in a carriage stop, but obviously it will be a bit more complex as it needs to shut off and brake the spindle/gears immediately. 

That said - for threading control you can do one of the following to avoid running into a shoulder:

1. cut a relief cut at the end of the threaded part so you don't have to thread all the way to the shoulder
2. thread from left to right (carriage moves from headstock to tailstock) - that way you start at the shoulder, and never have to worry about hitting anything. keep in mind to stay with a LH or RH thread you would need to position the cutter accordingly when moving in "reverse"


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## Ray C (Apr 4, 2013)

All,

Be careful with these things.  They're mainly intended for hand-wheel operation of the carriage.  Some lathes have a leadscrew and a driverod.  If the leadscrew is engaged and you hit the carriage stop somthing is going to get damaged.  With any luck, the shear pins will break.  Some (but not all) lathes with driverods have a slip-clutch engagement that pushes the carriage but won't break things if the carriage hits a stop.  I still wouldn't rely on that as a regular practice.

On my old Atlas, I made a carriage stop with an electrical switch that operated a solenoid to disengage the half-nut lever.  Been half-tempted to convert it over to my Precision Matthews.



BTW:  Some PM machines have slip-clutch driverods and some do not.  1236 e.g. does not.



Ray

- - - Updated - - -


Dead-on Sharon...  This is the way to do it.  It's basically a "reverse left-hand thread".  FWIW, I always cut a shoulder relief about 0.002 greater in diameter than my intended thread depth.  When the thread bit first hits that clean area, you know you're almost home.  When the threads are done, throw the groover at it and clean-up the scratches.


Also worth noting that for screw-on chucks, you need to be careful running in reverse.


Ray




PurpLev said:


> an e-stop can be included in a carriage stop, but obviously it will be a bit more complex as it needs to shut off and brake the spindle/gears immediately.
> 
> That said - for threading control you can do one of the following to avoid running into a shoulder:
> 
> ...


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## stevecmo (Apr 4, 2013)

As Sharon said, you need to have a relief at the end of the thread so you have some margin of safety to stop before crashing.  The other thing I do is use a dial indicator.  The carriage stop that I made isn't threaded for the actual stop.  It's bored 3/8" and has a clamp bolt so I can either put a piece of 3/8" drill rod in it for a stop, or put the DI in it.  It's pretty easy to measure where your relieve groove is, then just watch the DI to know when to disengage the half nuts.

Hope that helps.

Steve



tigtorch said:


> The reason for my stupid question arose from me threading an 8 tpi internal thread the other day.  Even in back gear at 50 rpm with a low thread count the carriage moves quickly and you have to be very quick on the halfnut to avoid hitting something.  I guess this stop was not intended to address that situation.
> 
> It would seem that it wouldn't be too hard to design an adjustable stop with an e-stop switch mounted on a spring loaded probe that allows enough travel to adequately stop the lathe in back gear.  Has anyone ever heard of something like this or done it themselves?


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## markknx (Apr 4, 2013)

PurpLev said:


> an e-stop can be included in a carriage stop, but obviously it will be a bit more complex as it needs to shut off and brake the spindle/gears immediately.
> 
> That said - for threading control you can do one of the following to avoid running into a shoulder:
> 
> ...



A third way to do this is to stop the lathe and turn the chuck by hand. (you can make a hand crank for the spindle for this)  I prefer a relief when possible. And of course there is always use a Die.
Yes this is soley for use manualy I do power feed up to it but then I go by hand. Thanks to all for the possitive feed back.


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## PurpLev (Apr 4, 2013)

for what it's worth - I made my carriage stop with a built in dial indicator so that I can get the powerfeed engaged to a few thou from the final stop, and finish off manually the last few thou:




I posted it here:
http://www.hobby-machinist.com/show...ing-lathe-Carriage-stop-ARO-(analog-read-out)


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## iron man (Apr 4, 2013)

I made one for my Atlas lathe with a brass dial I also made a lock on the shaft so I don't bump it and change my setting.. Ray


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## valleyboy101 (Apr 4, 2013)

A couple of nice carriage stop mark and Ray.

Ray-how did you do the engraving of the numbers and lines on your brass nut?  How did you do the hammered finish?
Michael


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## Bill C. (Apr 4, 2013)

tigtorch said:


> Please forgive a stupid question but how does this work? It would seem to me the right way to do it would involve an e-stop switch. I am obviously needing to learn more on this because I need one too.



Basically you set up a stop to cut a shoulder on a shaft face. Specially if you are cutting several copies of the same part. Also useful if your lathe dosen't have a carriage clamp to lock it in place. I probably confused you by now, sorry.

- - - Updated - - -



valleyboy101 said:


> A couple of nice carriage stop mark and Ray.
> 
> Ray-how did you do the engraving of the numbers and lines on your brass nut? How did you do the hammered finish?
> Michael



The finish looks like krinkle paint. Some tool-boxs are also painted like that too.  You can get paint that when it dries looks like someone took a ball-pein hammer to it too.


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## markknx (Apr 4, 2013)

valleyboy101 said:


> A couple of nice carriage stop mark and Ray.
> 
> Ray-how did you do the engraving of the numbers and lines on your brass nut? How did you do the hammered finish?
> Michael



Hey Michael, you left Sharon out, that was the one with the nice indicator. I like that and it is in the work for mine I left extra meat on the body so I could make additions if I want.


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## valleyboy101 (Apr 5, 2013)

You're right. I did inadvertently leave Sharon out. Sorry.  
Suffice to say they are all better than the one that I've got.  Which is none.  I had one for my previous lathe but haven't had a chance to make one for the new machine.
Michael


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## iron man (Apr 5, 2013)

valleyboy101 said:


> A couple of nice carriage stop mark and Ray.
> 
> Ray-how did you do the engraving of the numbers and lines on your brass nut? How did you do the hammered finish?
> Michael



I have an indexing head on my lathe I borrowed a carrage stop from a friend ground a cutter to a point and set in scribbing the lines. The numbers are 1/16 stamps I got from Grizzly. The paint is hammertone paint by krylon I really like there paint it takes a couple days for it to completely dry but after it is a couple weeks old it is tough as nails and stays put


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## seagar (Apr 6, 2013)

Another job to add to my to do list.It just grows and grows >:shrugs:


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## Moe6931 (Apr 6, 2013)

I've made a very similar stop for my Hercus AR (Southbend 9 inch clone) but I included a micrometer head for precise adjustment. It makes turning square shoulders a breeze. I would love to have an auto disengage feature for the power feed too but for the moment I'm doing OK with hand-eye coordination and finish the last little bit by hand.

Moe


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## BKtoys (Apr 16, 2013)

i really do like the stop with the dial indicator included with the stop. i will have to build me one simaler to it

thanks  Brian


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## Bill C. (Apr 16, 2013)

markknx said:


> I almos finished this today I just want to change the stop bolt. the socket cap is just a temp thing. After crashing compound the chuck a few weaks back it was time I did this.
> View attachment 51275
> View attachment 51273
> View attachment 51274


Nice job


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## Tim655 (Apr 22, 2013)

Nice work!!


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## darkzero (Apr 25, 2013)

Looks nice!


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## Ray C (Apr 25, 2013)

I know this might sound a little nutty but, my favorite carriage stop is a kitchen refrigerator magnet about the size of a business card.  -Just stick it on the ways and it stays put nicely.  Yesterday and today, I made 10 of these caps out of 316 stainless and when doing the threading, I look at the carriage and the magnet instead of the cut.  I have a carriage stop with a variety of attachments and one of them is a spring loaded stop bolt that gives way if the carriage bumps it.   Over time, I found the magnet works just fine. The point being (and I think it was stated somewhere down below) you don't want a power driven carriage hitting a firmly attached carriage stop.  -Ouch.

I was thinking one day (if I get around to it) of making another carriage stop with the top V-part made of thick plastic.

Ray


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## darkzero (Apr 25, 2013)

Good ideas Ray!


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