What's new
What's new

Making a Depth Micrometer Rod anyone make one ?

redlee

Titanium
Joined
Apr 2, 2009
Location
Beaver County Alb. Canada
Im missing a rod for a set and was just pondering trying and making one .
Drill rod, thread the end make some nuts and then using guage blocks set it up. Im retired and not using it for a living so I dont see why not!
Tell me why I shouldnt. Thanks
 
Go Fer It!

I wouldn't expect better than +/- .002" if you don't have a grinder to make the face perpendicular to the shaft.
Might be a good learning experience either way.
 
Go Fer It!

I wouldn't expect better than +/- .002" if you don't have a grinder to make the face perpendicular to the shaft.
Might be a good learning experience either way.

If you give me a lathe or mill, some duct tape and a rotary tool I'll get it flat enough you can't tell otherwise. Of course, you could make up a proper clamp and call it a toolpost grinder or a high speed auxilliary spindle, but what's the fun in that?
 
Be aware that the Starrett rod at MSC may or may not be the right length for the OPs 440. The rods for my 440A are very different than the one she measured for his 440.
 
I've done it -- and easily.

Buy some drill rod in the right diameter. Cut to length and thread an end. Thread isn't especially critical -- just there to adjust. You"ll likely have to turn the adjusting nuts down a bit to fit inside the cap.

Whether you harden the end is up to you. A 6" depth rod might not get used enough to be worth the slight effort. Make a lapping block (close fitting hole). I used diamond stones to get mine flat, then shiny flat. The block keeps the end at 90 degrees.

From there your accuracy is all in the adjustment. No reason it shouldn't be better than .001".

While you're at it, might as well make a 7" depth rod from the same stock. Or just save a long piece, already threaded for whatever strange depth measurement task the future might see. Just minutes to whack it off to length, polish the end, and adjust.

If you have truly accurate 1-2-3 blocks, a couple of them stacked make a good setup for adjusting your 6" rod. Sadly, you'll need to check -- the cheap blocks and even some of today's brand names aren't made to tenths (or even thousandths) -- just gang-ground to match.
 
I agree 100% with JR. They are very easy to make out of ejector pins with a v-block on a surface grinder. I made a complete set of 0-6" that are tapered for depth check of tapered ribs on molds. I just blued up the ends and ground the taper until there was about .030" of blueing left on the end. I didn't want to go to an extreme sharp tip due to damage/accuracy issues. They come in very handy.
 








 
Back
Top