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View Full Version : Starrett Level Vial Mounted - Pic



CCWKen
03-18-2006, 08:39 PM
After the thread (argument) about getting a lathe leveled or for the purists getting the bed straight in all axes, I dug one of my Starrett level vials out of my stash and mounted it to one of my 12" test bars. I'm happy with it.

http://img.photobucket.com/albums/0903/CCWKen/Tools/Misc/StarrettLevel-1.jpg

After getting the vial adjusted to a rough level (some fine tuning is still necessary), I checked the sensitivity. I placed a .003" shim under one side and it moved the bubble a full index mark! Like what's shown here at the right side of the bubble.

http://img.photobucket.com/albums/0903/CCWKen/Tools/Misc/StarrettLevel-3.jpg

I think once I get the vial fine adjusted, It would be easy to detect a variance of .0005" or less. One thing for sure, ya gotta make sure there's no gnat hairs or dust specs under it. I'll have to see how far my equipment is out of whack.

larry_g
03-18-2006, 09:36 PM
I think that when you get this level all calibrated you will find that the vial is calibrated at .005" per foot. Looks goodl
lg
no neat sig line

HTRN
03-19-2006, 02:02 AM
A really easy trick for adjusting levels is to simply turn it around. If it's square with the reference surface, it will show the same amount of off center no matter which end you orient with.

Learned that on "Ask this old House" http://bbs.homeshopmachinist.net//biggrin.gif


HTRN

JS
03-19-2006, 02:03 AM
I would like to know how accurat it is . When or if you tested please let us know .

I might want to make one too . lol


thanks

Leigh
03-19-2006, 07:06 AM
This looks like a vial from a Starret 98 Precision Mechanic's Level, which is rated .005" per foot. McMaster-Carr http://www.mcmaster.com sells the replacement vials for $30 to $75, depending on size, on page 2142 of their catalog.

You can also get the vial for the 199 Master Precision Level, rated .0005" per foot, for $46 on the same catalog page. That's a lot better than $600 for the complete level.

------------------
Leigh

[This message has been edited by Leigh (edited 03-19-2006).]

torker
03-19-2006, 08:08 AM
Ken, good idea! Where do you get a "test bar"? I just looked in my KBC catalog and they don't list such an animal unless they call it something else.
Also they don't list the Starrett vials seperate.
I'm interested as we will soon have to level up the ol' McDougal lathe.
It's still beyond me how we can twist that massive piece of cast but I'm sure I'll get flamed into understanding http://bbs.homeshopmachinist.net//biggrin.gif
Russ

sdeering
03-19-2006, 08:24 AM
You should calibrate it on a flat surface not carpet. http://bbs.homeshopmachinist.net//rolleyes.gif

beckley23
03-19-2006, 10:11 AM
You can make a "test bar" from precision ground stock. I would prefer Meehanite for this purpose. Scrape the leveling surface flat, and mount the vial.
Adjust the vial for level reading, then calibrate the divisions by sitting the vial on two gage block stacks of the same height, one at each end. Then change one of the stacks in small increments to see what the divisions really are. You can use shim stock for this , but the gage blocks are more accurate and a known dimension.
Harry

CCWKen
03-19-2006, 03:32 PM
<font face="Verdana, Arial" size="2">Originally posted by sdeering:
You should calibrate it on a flat surface not carpet. http://bbs.homeshopmachinist.net//rolleyes.gif</font>

LOL... Really? http://bbs.homeshopmachinist.net//biggrin.gif The blue towel is used for photographic purposes only. I roughed in the gage on a surface block just to test sensitivity. I haven't even tightened the lock nuts. It may be a .005/foot vial but it's certianly sensitive enough to show a variance of much less. I don't need to measure the variance but simply know that there is a variance off level. Right? http://bbs.homeshopmachinist.net//rolleyes.gif

CCWKen
03-19-2006, 03:47 PM
Russ, my test bar is from an automotive supply house. It's used for testing flatness on a head or engine block and a few other tests. It had some "spider legs" that attached at the holes but over the years, those have disappeared. As Harry said though, you can simply order precision ground stock from any of the suppliers.

Doc Nickel
03-19-2006, 04:03 PM
As for the vial adjustment, I see you have a threaded rod and two jam nuts. I wonder if a simple panhead screw and a small but reasonably stiff spring might make the adjustment easier.

That way you just need to lightly tweak the screw, rather than loosen/tighten the jam nuts.

Doc.

CCWKen
03-19-2006, 04:17 PM
Doc, that would probably work but the other end uses a ball and socket. If the vial is not captured or held tight, the mounting holes would allow for some movement. You'd end up having to readjust for each use. It is super sensitive!

The studs are #10-32 and moving the nut(s) less than an eighth of a turn will move the bubble from one end of the vial to the other. http://bbs.homeshopmachinist.net//eek.gif

J Tiers
03-19-2006, 06:41 PM
<font face="Verdana, Arial" size="2">Originally posted by CCWKen:


The studs are #10-32 and moving the nut(s) less than an eighth of a turn will move the bubble from one end of the vial to the other. http://bbs.homeshopmachinist.net//eek.gif</font>

I'd sure hope so. 1/8 of 32tpi is about 0.1mm (.0039 inch), and the sensitivity is 0.005 inch per 10 inches.

The vial is about 5" long, so you are essentially moving a 0.005 inch sensitivity vial 0.008 inches. It better "peg out" the bubble!

You do however show up the reason hardly anyone needs a "master precision" level....the 0.0005 dealie-bobs.

Those "peg out" if you look at them hard, and are not much use for roughing in a lathe bed.... Fine as a substitute for the "two-collars" test, but lots more expensive.

Yours is easier to use, and gets you in the range where you can then adjust with two collars, or (shudder) RDM.