# Micrometer Stop (with issue)



## walterwoj (Dec 16, 2021)

This is my micrometer Stop based on tubalcain's video on YouTube (if you haven't seen his videos you are missing out!)







It fits well, has a graduated dial and the bluing came out perfect! 

The dial is off a little bit though, I have learned the hard way that there should be 49 divisions on it, not 50 so it has an extra hash mark (lol), but it looks right. I used red nail polish to highlight the marks.

It just has one problem:. It moves! When I tighten the knob down as hard as I can by hand it seems really tight; I can't move it by hand, but as soon as the carriage touches it, it moves. If I run the carriage by hand it moves with the slightest touch and when the carriage is under power (not threading though!) It pushes it right allong the ways.

Did I build it wrong or does it just take a lot more clamping force to resist the carriage?

Here are a couple pics of the pieces:












Sent from my Pixel 6 Pro using Tapatalk


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## woodchucker (Dec 16, 2021)

walterwoj said:


> This is my micrometer Stop based on tubalcain's video on YouTube (if you haven't seen his videos you are missing out!)
> 
> 
> 
> ...


Wow, your chuck is very close to the ways. How big is your lathe, and what size chuck is that?
Be careful when opening your jaws or bringing the carriage in close.


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## Ken226 (Dec 16, 2021)

Just a possibility, but based on this screen capture, zoomed in from your pic,

It looks like maybe your lower clamping block is being pulled against the carriage stop and not so much against the underside of the ways.

If so, perhaps mill a about 30 thousandths off the bottom of the carriage stop.





Also,  letting the powerfeed push a carried stop down the ways would scare me!     I'd be scared of breaking something, but then, I'm a chicken!


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## walterwoj (Dec 16, 2021)

woodchucker said:


> Wow, your chuck is very close to the ways. How big is your lathe, and what size chuck is that?
> Be careful when opening your jaws or bringing the carriage in close.


It's a 10 1/4-1/2 in lathe and that is a 10 inch chuck!  It's tight and I am always careful of the jaws for that reason.  The carriage has enough room to run under the chuck without issue but it's tight, don't want my finger in there when it's running.  someday I want to get a 5-6 inch 4 jaw for it.  I have a 6 in 3 jaw but due to some mistakes I made, the jaws are messed up and I need to acquire a post grinder to fix so it doesn't see much use right now.


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## RJSakowski (Dec 16, 2021)

Modify your clamp as below to create a pivot point.  Make tha pivot as far back as possible for best leverage.


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## woodchucker (Dec 16, 2021)

walterwoj said:


> It's a 10 1/4-1/2 in lathe and that is a 10 inch chuck!  It's tight and I am always careful of the jaws for that reason.  The carriage has enough room to run under the chuck without issue but it's tight, don't want my finger in there when it's running.  someday I want to get a 5-6 inch 4 jaw for it.  I have a 6 in 3 jaw but due to some mistakes I made, the jaws are messed up and I need to acquire a post grinder to fix so it doesn't see much use right now.


just so you know if you don't, that chuck is meant for a 14 - 16 inch lathe. Be careful.. yea your finger, or metal flying.. 
Like they used to say on Hill Street Blues... lets be careful out there.
Good luck.. stay safe.


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## walterwoj (Dec 16, 2021)

Ken226 said:


> Just a possibility, but based on this screen capture, zoomed in from your pic,
> 
> It looks like maybe your lower clamping block is being pulled against the carriage stop and not so much against the underside of the ways.
> 
> ...



I thought that was a possibility so already I did just what you suggested,  I am sure it is not bottoming out but it did not fix or even improve the situation.

I have to admit I don't know the use of the carriage stop very well but I ASS-U-MEd that it should be able to stop the carriage under power-feed.  I have tested it well away from the chuck where I can stop it before it does damage.  I know that using it when threading is a no-no but I'm sure it should work when I am hand feeding it, but it just slides.  I'm beginning to think the reason that every version I've seen before has a bold is hat you need a wrench to get enough torque to hold it tight.... It WILL hold if I take a pair of pliers to the thumbscrew, but I was trying to make it tool-less, I might just cut a hex head into the top of the thumb screw....


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## walterwoj (Dec 16, 2021)

RJSakowski said:


> Modify your clamp as below to create a pivot point.  Make tha pivot as far back as possible for best leverage.
> 
> 
> 
> ...


RJ what mechanical advantage does that give?  Wouldn't it only grip on the tip on the right?  (also I would have to cut down the body of the stop to gain enough clearance for that so I might save that for last resort as there is currently a broken tap in the stop and I don't have a endmill that would survive that operation....  As tubalcain would say, I have painted myself into a corner....)


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## Ken226 (Dec 16, 2021)

walterwoj said:


> I have to admit I don't know the use of the carriage stop very well but I ASS-U-MEd that it should be able to stop the carriage under power-feed.



Unless there's some mechanism or clutch that I don't know about to kick the powerfeed off when the carriage contacts the micrometer stop,  something will likely break/bend.  

My lathe definitely wouldn't auto-off the powerfeed when it hits the carriage stop.  I only use the stop while hand-feeding.

For the block,  

Try the design that RJSakowski posted.  The added leverage will help.   It doesn't give mechanical advantage,   it just causes the block to transfer all it's force to the underside of the ways instead of into the body of the carriage stop.

If you use the same block to do it, you will also need to take an equal amount off the bottom of the carriage stop, so the block is level when in contact with the underside of the ways.  Otherwise the screw itself will take the stress of it trying to pivot, and not allow enough force be applied to the ways.


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## RJSakowski (Dec 16, 2021)

walterwoj said:


> RJ what mechanical advantage does that give?  Wouldn't it only grip on the tip on the right?  (also I would have to cut down the body of the stop to gain enough clearance for that so I might save that for last resort as there is currently a broken tap in the stop and I don't have a endmill that would survive that operation....  As tubalcain would say, I have painted myself into a corner....)


The gripping force on the lathe way will always be less than the clamping force of the screw, the ratio of which is inversely proportional to the respective distances to the fulcrum. (3rd class lever).  The decrease can be minimized by making the two distances as near as possible to equal, hence the longer distance to the pivot point.  You should be able to increase your clamping force by around 3X.


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## mikey (Dec 16, 2021)

The reason your stop is slipping is because the angles underneath it, the angled parts touching the ways, are inaccurate. You only have contact on the inner v-way and none on the outer one. No amount of clamping force will hold the stop solidly. Fix the angles and just a little force will lock it down.

EDIT: also make the center cut deeper so it doesn't touch the flat on top of the way. If it touches, the angled surfaces will not register solidly and you cannot lock it down.


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## Just for fun (Dec 16, 2021)

It looks like the stop is only gripping on the little section on the inside of the way and the flat on the top.  If you could get this portion to hit before it bottoms out on the flat top, I'm sure it would work better.   But as Ken said unless your machine has a clutch you should only use the stop when hand feeding.

Tim

Edit:  Forgot the photo.


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## Ken226 (Dec 16, 2021)

Yea, Mikey's got a good eye.  I didn't even see that earlier.


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## Janderso (Dec 16, 2021)

Mikey and RJ know their business.
Learning to do the job properly helps us all.
Don’t get discouraged, keep at it and let us follow along.
This is not a simple project.


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## benmychree (Dec 16, 2021)

Comment on using a carriage stop when threading; NEVER!  If the stop is contacted, it makes it impossible to disengage the half nuts, and breakage of something is very likely.  Carriage stops need to be tightened quite tight, a knurled knob is nowhere nearly up to the job, and in my opinion, the stop should have contact with both sides of the vee way.


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## woodchucker (Dec 16, 2021)

Just for ideas.
I don't like putting my micrometer stop on and off, so when I made a holder for my dial indicator, I made it so I can just pull back the bottom and then push it forward to keep it on.


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## Ken226 (Dec 16, 2021)

@walterwoj 

Woodchucker's strategy for the V on his carriage stop is a good example of an easy way to repair yours. Maybe.

The narrow and raised flat in the top of the V means that his V will fit with full contact on both angled faces,  even if his he misses the mark a little and makes the V too wide, or too narrow.  As long as the angle is correct, it'll fit with full contact on both faces.   The width of the v becomes less critical.

On yours,  the angle doesn't look incorrect, but the top of your V appears to be sitting on top of your ways.


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## Alcap (Dec 17, 2021)

I thought a carriage stop like you made was to power feed close and finish to the stop by hand ?  Maybe your lathe has some kind of self release clutch ?  I have a factory stop on my Clausing not as nice as you made but there’s a clutch kick out bracket that would let you have some type of power feed stop .


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## aliva (Dec 17, 2021)

could also replace the thumb screw with a socket head screw, more torque, I have 2 on mine


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## 682bear (Dec 17, 2021)

The carriage stop is not supposed to stop the power feed... it is meant to be a 'hand feed' stop.

I use the feed until I'm close to the stop, then disengage the feed and hand feed the last .020" or so... just until I touch the stop.

Even hand feeding, you could potentially move the stop if you run into it hard.

-Bear


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## woodchucker (Dec 17, 2021)

On my SB9 the clutch on the apron will slip if you set it light enough. It's not meant really to slip, but it can be done. You need the star knob.
I also let it feed until just before , turn it off, then feed by hand.. I would rather do that then have to rebuild the clutch mechanism.

I will probably modify my carriage stop to have the bolt on top, and have the plate slide like I am doing on the indicator holder.


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