Test Indicators for barrel/chambering work ?

M

matchman

Guest
I have a B&S .0005 per line. Is this accurate enough ? Or should I be looking at getting a .0001 per line ?

I need a probe extension for the B&S ($40)
or I think I can get a Mikioto for around $100 for the job.

Your Thoughts ?

Thanks
Adam
 
matchman said:
I have a B&S .0005 per line. Is this accurate enough ? Or should I be looking at getting a .0001 per line ?

I need a probe extension for the B&S ($40)
or I think I can get a Mikioto for around $100 for the job.

Your Thoughts ?

Thanks
Adam
Click to expand...

Once you add the extended stylus to the B&S you no longer have a .0005 reading indicator. The longer you go compared to the original, the lower your resolution per line will be.

B&S does offer a long stylus test indicator with .0005 resolution, but not .0001. Interapid offers a .0001 test indicator, and some are using the Mitutoyo with small rounded body that will fit into a chamber to get readings further into the bore that standard test indicators.

Please note. I am no machinist or gunsmith, so maybe the real experts will chime in.

Jim
 
Mitutoyo 513-504/small body/.0001"/usable length body+stylus 2"
Interapid 074111965/.0005"/long stylus 2.75"
These two indicators are very popular for gunsmithing. I have and use both.
 
You don't necessarily need a 0.0001" indicator for chambering work but you do need an indicator that has light enough tracking that it will display any movement of the stylus tip.. That is, if the stylus moves any at all the dial will display the change. The very best dial indicator made is the Interapid....period!!!

With a top quality indicator, and indicating for the chamber neck, you are not concerned with HOW MUCH movement, you are concerned with ANY movement.

Read what the dial indicator experts have to say-- these folks have been in the dial indicator sales and repair business for over 40 years. They have seen and repaired them all.

http://longislandindicator.com/p116.html
http://longislandindicator.com/p23.html
 
Also..............

JerrySharrett said:
You don't necessarily need a 0.0001" indicator for chambering work but you do need an indicator that has light enough tracking that it will display any movement of the stylus tip.. That is, if the stylus moves any at all the dial will display the change. The very best dial indicator made is the Interapid....period!!!

With a top quality indicator, and indicating for the chamber neck, you are not concerned with HOW MUCH movement, you are concerned with ANY movement.

Read what the dial indicator experts have to say-- these folks have been in the dial indicator sales and repair business for over 40 years. They have seen and repaired them all.

http://longislandindicator.com/p116.html
http://longislandindicator.com/p23.html
Click to expand...


Also, make sure that you are using a solid base and indicator arm setup.

Over half the gunsmith I see who have gone to all the extra expense and troubles in getting the best .0001 indicators and long stylists, then attach them to the flimsiest and over extended base/arm setups, that in the end reduce their real world resolution to the .002-.003 range, and they go on happily thinking that they are working in the tenths. Some are revered gunsmiths on this very messageboard................Don
 
Indicators

It depends on the way you chamber. If you pre-drill, indicate throat area, and pre-bore, then the little Mitutoyo is great. You can reach in pretty far with pin point resolution.

For other methods, the Interrapid would be my choice.........jackie
 
jackie schmidt said:
It depends on the way you chamber. If you pre-drill, indicate throat area, and pre-bore, then the little Mitutoyo is great. You can reach in pretty far with pin point resolution.

For other methods, the Interrapid would be my choice.........jackie
Click to expand...
There are several dial indicators on the market, Mitutoyo, Starrett, Lufkin, Fowler, Brown & Sharpe, et al, that will work for benchrest quality chambering, if, like Don mentions, are properly set up.

However, in formal benchrest, you are working toward the very best, so it stands to reason, why not use the best dial indicator? That dial indicator is the Interapid 300 series!!!! Fact!!!

And yes, I do drill, and prebore, just like Ferris Pindell did for many many years.
 
Don said:
Also, make sure that you are using a solid base and indicator arm setup.

Over half the gunsmith I see who have gone to all the extra expense and troubles in getting the best .0001 indicators and long stylists, then attach them to the flimsiest and over extended base/arm setups, that in the end reduce their real world resolution to the .002-.003 range, and they go on happily thinking that they are working in the tenths. Some are revered gunsmiths on this very messageboard................Don
Click to expand...

OK, then who do you think makes the best indicator holder for chambering?
 
adamsgt said:
OK, then who do you think makes the best indicator holder for chambering?
Click to expand...

Hi Jerry,

I am not sure, mine are custom made/my self, or I use the one that I have directly attached to a quick change tool holder which I use mostly for chambering work requiring a .0001 indicator with long stylus, as all I have to do is indicate the chamber, back the indicator out and replace it with a cutting tool and commence making chips.

I can say, shy away from any indicator holder/base setups using less than 3/8" diameter rods, and always have the holder/base no more than a couple inches from the work piece, short as possible, without interfering with the operations. These guys that are using 1/4" holder/bases extended to 6" away from the working piece, hoping to work in the .0001" are fooling themselves.....................Don
 
Gene

Most small indicators that are suitable for barrel work come with a rod assy or a rectangle mount that you can place in a tool holder.

If you look at the pictures in the post showing me chambering a barrel, you will see what I use. Very handy, and rock solid........jackie
 
Don, as the saying goes " a picture is worth a thousand words" Maybe the next time you do a setup you could take a couple of pictures and post them for our benefit.

Gene, I have a Noga that is probably just like yours and I like it.

Jackie, I believe I saved the link to your post and I will review it again. When you talk about holding the indicator in a tool holder I'm assuming you're talking about an Aloris type that you can quickly swap out for a cutting tool?

I think the most difficult part, for me, of using the indicator is finding the best place to put the mag base. Thrashed around a lot recently when I was truing the D1-4 adapter to mount my Bison 5C chuck and then check runout. Seemed like every time I found a good place for the base the dial face was pointing away from me. I'm beginning to wonder if I have some particular difficulty in visualizing spatial relationships in my head. Not a good sign. :eek:
 
Gene DeLoney said:
Noga magnetic base.....extremely easy to use compared to the arm types.
Love mine.
Gene
Click to expand...
One of the bigger problems in using a magnetic base, especially on a lathe is that the base is....magnetic. It tends to pick up every little particle and put those particles between the base and the machine.

Clamping the indicator shank in a tool holder is the most rigid. Clamping it in a tool holder also gives you two axis of motion you can use to position the indicator stylus point without having to force it around and possibly damaging the innards of the indicator.
 
JerrySharrett said:
One of the bigger problems in using a magnetic base, especially on a lathe is that the base is....magnetic. It tends to pick up every little particle and put those particles between the base and the machine.

Clamping the indicator shank in a tool holder is the most rigid. Clamping it in a tool holder also gives you two axis of motion you can use to position the indicator stylus point without having to force it around and possibly damaging the innards of the indicator.
Click to expand...

The Noga has a on/off lever. In the off position, the base is non magnetic so the clinging chips is not a problem.
My Rockwell lathe has a nice flat spot on the carriage which I wipe clean before placing the mag base.
BTW I like the lever on/off better than the push button type which tend to slide when you try to push the button on.
Just my preferences........Gene
 
adamsgt said:
Don, as the saying goes " a picture is worth a thousand words" Maybe the next time you do a setup you could take a couple of pictures and post them for our benefit.
Click to expand...

My micrometer tool holder setup is very similar to Jackies;


125hyjm.jpg


And for goodness sakes always keep your shop shirts buttoned and tucked in, not dangling into the power feed/screw engagement mechanisms. Alot of new gunsmiths follow Jackies postings, lets keep it that way, so that he will be around and contributing for many years to come.


necpdw.jpg
 
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Using the tool holder to hold the indicator makes a much more rigid setup and it gives two axis of machine motion (the cross feed slide and saddle) to more precisely position the stylus.



dhcqvl.jpg
 
OK, in Jackies picture that must be the Mitutoyo indicator with the long round body. The best price I've seen on the Interapid long point was $273.00 at Penn Tool Co.

Just out of curiosity, does anyone have use for vertical test indicators on a lathe? I don't have any but I can envision that they would be useful on a mill.
 
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JerrySharrett said:
That dial indicator is the Interapid 300 series!!!! Fact!!!
Click to expand...

While that may be true Jerry, using .0005 to indicate accuracy still seems weak to me! :) Might as well just say .001, it's certainly not a "tenths indicator," more like a "half a thou" indicator......

al
 
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