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WilliamG
11-01-2009, 11:51 AM
What are the advantages or disadvantages of a carriage stop that incorporates a micrometer to that of a dial indicator other than cost?

How does one remove a micrometer from it's frame besides carefully?

Ask this because I'm new to running a lathe and never used a carriage stop.

Bill

Forrest Addy
11-01-2009, 12:07 PM
A micrometer carriage stop merely look looks like a micrometer was gutted to make it although very small lathes could probably use one.

A micrometer carriage stop consists of a blocky clamp designed to fit the carriage way with an extendible screw to stop the carriage. The "micrometer" part comes in when a graduated collar is use to adjust the axial position of the stop screw. Very satisfactory carriage stops have been made using a screw adjustment alone.

Anyone desireing to DIY his own carriage stop for a 14" and smaller lathe might look at using a quill stop collar from a Brifgeport mill head. They are available from a parts house for only a small fortune. They are intended for a 1/2 - 20 UNF screw so the shade tree guys can use a piece of all thread. Otherwise machine a stop screw and cut the threads on it. You will have to cut an anti rotation keyseat on the screw otherwise it's a plain vanilla operation.

As for the repative merits of an indicator stop they are about equal but each (micrometer and indicator) has its separate and distinct virtues. I suggest makeing both.

winchman
11-01-2009, 12:12 PM
The dial indicator gives you an accurate reading of the distance to the stop. You could use it to position the carriage to take a very light finish cut.

With the micrometer, you've got to judge the distance by eye or fiddle with the micrometer between cuts.

I've got a dial on my carriage feed handwheel, so my carriage stop doesn't get much use.

Roger

Evan
11-01-2009, 01:25 PM
A carriage stop with a dial guage isn't a carriage stop. It's a position indicator. One with a micrometer IS a stop and once adjusted you needn't refer to it to make a series of similar cuts. Big difference.

darryl
11-01-2009, 04:39 PM
A carriage stop- I made a very simple one. I drilled and threaded a piece of metal that I could bolt to the back of the headstock. Then I cut the upper part off to leave a hollow with threads in it. That is mounted with the hollow parallel to the bed.
The carriage is adjusted to where you want the limit to be, then a piece of all-thread is laid in the hollow such that it butts up to the side of the carriage. You can spin the all-thread to make a fine adjustment, then clamp it in place with a small c-clamp.

I was going to add a pair of screw-on bits to it, one would be fixed in place, and the other would be able to screw in and out a little. Suitable marks would let you adjust the movable piece by known amounts to fine tune the stop.

Mcruff
11-01-2009, 06:05 PM
Here is the one I made for my 9" South Bend. I use gage blocks with it to get longer lengths. Its has 1.00 of travel and is .050" per revolution, marked off in .001" increments. Works great, and unlike a DI is a positive stop when making parts.
http://i6.photobucket.com/albums/y233/mcruff/Southbend%20lathe/Micrometerstop2.jpg
http://i6.photobucket.com/albums/y233/mcruff/Southbend%20lathe/Micrometerstop3.jpg

Boucher
11-01-2009, 06:25 PM
This carriage stop came with my lathe. It is a very usefull tool.
http://i109.photobucket.com/albums/n50/boucherbyron/micrometerstop.jpg
With the micrometer graduations it facilitates accurate facing or sholder turning. Sorry about the photo quality, still learning.

Carld
11-01-2009, 08:27 PM
Simply put a micrometer stop gives a positive stop to run the carriage to by hand of course. A dial indicator stop is not really a stop but is used to indicate where you want to stop the carriage.

If your boring a blind hole a carriage stop is just what you need because with each pass you can stop the carriage against the stop and that is as far as it will go. If you use an indicator for that purpose it is very easy to go to deep and when you do the boring bar will catch on the bottom and cause ugly things to happen.

There are times to use both of them and as Forrest said make both of them.

Pherdie
11-01-2009, 08:44 PM
Carld wrote:
Simply put a micrometer stop gives a positive stop to run the carriage to by hand of course.

So if I had a clutch type drive on my carriage (IE: South Bend 9A), would be improper use to drive the carriage into the micrometer stop with light clutch application and then disengage upon termination of travel? I've always assumed so, but had no definitive knowledge.

Fred

HSS
11-01-2009, 09:44 PM
What would be considered a light clutch application. I don't think I would trust running into a stop under power even if I knew that it was ok to do so. Murphy sneeks up on me enough as it is. But thats me.:D

tattoomike68
11-01-2009, 10:34 PM
Carld wrote:

So if I had a clutch type drive on my carriage (IE: South Bend 9A), would be improper use to drive the carriage into the micrometer stop with light clutch application and then disengage upon termination of travel? I've always assumed so, but had no definitive knowledge.

Fred


LOL like a slow speed crash. I say dont do it.

Black_Moons
11-02-2009, 03:24 AM
No your supposed to do the last bit manualy, also not sure about others but even reasonabley tightened my carriage stop will move a few mills if given a good ram by the carriage, so you gotta be really gental to use it.

Boucher
11-02-2009, 08:12 AM
This shows the Nardini Feed Stop.
http://i109.photobucket.com/albums/n50/boucherbyron/feedstop2-1.jpg

This shows the feed stop trigger engaged.

http://i109.photobucket.com/albums/n50/boucherbyron/stoptriggercocked.jpg

This shows the feed stop trigger tripped. It bonks the chip pan hard enough to startle you whenever it trips.

http://i109.photobucket.com/albums/n50/boucherbyron/stoptriggerreleased.jpg