Do you keep a micrometer at your casting bench?

[dmftoy1]

Just curious. I did it recently while trying to get some .314 slugs out of a 314299 and it was nice to be able to do a QA check every so often to make sure they were coming out as big as I wanted.

What do you do?

Regards,
Dave

[Blammer]

yep............

[crowbeaner]

Absolutely. Both a dial caliper and a Starret 0-1" micrometer. I also have the RCBS slider for those metric measurements.

[454PB]

I can't imagine anyone handloading or casting without several good measuring devices.

[Harry O]

A caliper and a magnifying glass. I have micrometers if the caliper shows that something might be wrong.

[danski26]

Yes, several mics and a caliper sprinkeled around the work loading room.

[corvette8n]

Usually a dial caliper, but I do have a mic also.

[MT Gianni]

Both in the basement where I load. None in the shop where I cast unless I have recently modified a mold or have reason to suspect it. Gianni

[Swamprat1052]

Yep I have the caliper and micrometer too. Must haves as far as I am concerned.

Swamprat

[NVcurmudgeon]

Like Gianni I keep the .0001" mike and the dial caliper, both Starrett, in the semi-clean loading room. Casting is done in the not quite so clean gagage.

[BCB]

Me too with the mike and the steel calipers--both Starrett...BCB

[hornetguy]

Absolutely. Both a dial caliper and a Starret 0-1" micrometer. I also have the RCBS slider for those metric measurements.

exactly... mitutoyu dial, and starrett mic.... and an opti-visor.... I'm over 40.

Ok, a LOT over 40.

[Kraschenbirn]

Yep! Mitutoyo 0-1" mic along with both digital and vernier calipers in the drawer under the workbench where I do my casting and BP reloading (not at the same time :-))

Bill

[JeffinNZ]

Metric and imperial. Cos the only better than having a micrometer is having TWO micrometers.

[JIMinPHX]

I have a set of tenth reading mic's in the shop, in fact I have a pretty good selection of that stuff. But I seldom use anything other than a pair of calipers for measuring boolits. Soft materials like lead are hard to get an accurate number with using a mic. The mic digs into the diameter of the soft material when you turn the handle in, even with a spring slip ratchet on the thimble or a good sense of feel. I can get an accurate number with the mic if I have to, but it's not worth the bother. I can estimate down to a few tenths on the dial. That's good enough for this stuff.

On even softer materials, like precision ground 40 Duro rubber rollers, I take measurements by putting pieces of low carbon ground flat stock across the roller to spread out the stress of the measuring instrument & decrease the deflection. I could pull that trick here too if I had to, but it's a pain in the backside.

if you really want to get a number that you can trust down to .0001" on a soft diameter like lead, you should really be using ring & plug gages, not mics.

[Ben]

I wouldn't be without this one.......A fine mic :

http://img.photobucket.com/albums/v494/haysb/311284%20Plain%20Base/PICT0005.jpg

[theperfessor]

I cast in my garage/machine shop where I have ventilation and a full set of mikes and verniers of various brands and ages.

I load in my lockable "armory" in the basement where I keep my loading supplies and guns. I keep a 6" dial caliper, a 0-1" outside mike, and - most useful for measuring chamber mouths and cartridge neck inside diameters - a 0.2" - 1.2" inside mike. Makes matching up bullet diameters to revolver chamber mouths a snap! Real handy to have. Check www.use-enco.com.

[HORNET]

The tenth-reading mic sets on top of the case for the calipers on the table behind me from the press bench. The spare mics are beside the lubri-sizers on the other bench. Those mics are both 1" capacity. The bigger mics are hanging on the gun cabinet doors. Never know what you're gonna need sometimes...

[waksupi]

I have two here at home, one on my bench at work, and there are another half dozen scattered around the shop at any given time.

[7s&8s]

I have Starrett micrometer and dial caliper by Central. Both acquired second hand, and no apparent abuse to either...
I pretty well cured myself of trying to mix and match the two (unless I'm looking for serious entertainment...) in the .25 to .45 range, typically .001-.002" difference.
The micrometer gets the most exercise these days...

[boommer]

I leave mine in the gun room I do all casting outside and I know what my mold throws if it's a new mold or something don't look right just take it to the room not that big of deal it's warm and reading right. I cast when it's cold. I have been known to dip the pot at 10 degree mark, fire and the pot keeps you warm but nothing else.

[Bill*]

Yup... a nice 0-1 Brown and Sharpe ( it makes a great temp C-clamp too-JUS' KIDDIN" )

[dmftoy1]

Thanks guys!

I'm specifically asking if you keep one near the casting pot when you're casting. I've always had one in the reloading room in the basement but I do all my casting out in the garage to keep the significant other happy. :) (I always check them when loading)

It occured to me after my first try with 314299's. I ended up with a whole bunch at .310 when they should be .313-.314 and I had to throw them all back in the smelting pot for conversion to ingots. If I had a cheap mic or caliper I could check them as they were cast and make adjustments before I did a whole batch. (Seemed to work alot better that way)

I guess I just need to watch midway for another one of those deals on Frankford Arsenal calipers . .I think I got the last set free and gave them to a buddy who was just starting out.

Have a good one,
Dave

[JSnover]

You might also try Enco or Grizzly for a 'competitively priced' mic or caliper. Good chance they're all coming from the same group of manufacturers (Fowler, Mitutoyo, etc). Lots of people have had good luck with them.

[AZ Pete]

I have a digital caliper and a 1" micrometer in my bench. Use them frequently.

[grumpy one]

I was brought up to separate the "clean" from the "dirty" shop operations. Dirty means gritty, not nice clean swarf and oil of course. So, the machine shop is separate from the dirty shop, which combines grinding and casting/smelting operations, and the work-bench is in the dirty shop. (I originally had both clean and dirty benches, but that was before I bought an oversize milling machine and had to sacrifice the clean bench). So, the "frequent use" metrology gear lives in the clean shop, and the "occasional use" metrology gear is stashed in the storage area (the cellar). When I want to measure a bullet, or even set up overall length of a cartridge, I pick it up and take it to the workshop - about a twenty foot trip, but with a closed door in between.

[TxGunfighter]

Dial Caliper and a 1" OD Mic, could not function without it!
TxGunfighter

[floodgate]

Mitutoyo 1" mike and Sears/Craftsman 6" vernier in the top drawer under the lathe, within easy reach but protected from dust and dirt. Craftsman 1", 1"-2", and 1" - 6" anvil mikes and 6" US and metric dial calipers in the big toolbox across the room; and an 18" vernier caliper I got for a special job several years ago, around somewhere.

I've heard various opinions as to how close you can REALLY read a caliper (or even a mike); some say no better than 2-3 thousandths. Well, I apprenticed to a musical instrument maker, and - after a month or so, working with him (and he was a REAL fuss-budget!) when doing soundboards for a production run of hurdy-gurdies (DON'T ASK!) - on a thickness sander we could co-ordinate our measurements - different vernier calipers, in different hands - to the nearest 0.001", and that was on wood (spruce)!

Impossible? But it worked for us!

floodgate

[Shuz]

I use a mic and a caliper in my loading room, but not out in the shop where I cast. If I start using a new (to me) mould, I'll bring the mic out to the casting area before I cast a bunch of potential "rejects"!

[JSnover]

I've heard various opinions as to how close you can REALLY read a caliper (or even a mike); some say no better than 2-3 thousandths. floodgate

I've heard the same thing and it just isn't true, as you found out.
If it's accurate and it's zeroed you can read it to whatever the scale is calibrated to; A dial caliper with .001" increments on the face is accurate to .001". If the needle falls between the lines your calibrated eyeball will be within .0005". Vernier calipers confuse some people but they read to a smaller increment, so they're more precise (which is not the same as being more accurate). Same applies to mics that read to .0001" using a vernier scale on the barrel. You can guesstimate to within .00005" with them.

[grumpy one]

Be careful with vernier calipers - don't take them too seriously until you've calibrated them against something like a good micrometer. I have an Asian vernier caliper that looks well made and is easy to use, but I've found it to be .007" out in one actual measurement - there may be points in its range where it is even worse. It isn't too serious a problem if you know what measuring instrument you used for a particular measurement, since unless they have slack or are springy, vernier calipers will repeat the same measurement and get the same reading. However if you use a decent micrometer one day and a Chinese vernier caliper the next, you may get the wrong idea.

[Shiloh]

Yes.

I have the mike handy on the bench.

Shiloh

[JSnover]

Be careful with vernier calipers - don't take them too seriously until you've calibrated them against something like a good micrometer. I have an Asian vernier caliper that looks well made and is easy to use, but I've found it to be .007" out in one actual measurement - there may be points in its range where it is even worse. It isn't too serious a problem if you know what measuring instrument you used for a particular measurement, since unless they have slack or are springy, vernier calipers will repeat the same measurement and get the same reading. However if you use a decent micrometer one day and a Chinese vernier caliper the next, you may get the wrong idea.

Absolutely. I have a brand-new Starret 6" caliper, complete with certificate of calibration from factory... and it's .003" out. Better yet, of the three I've been working with, only one is less than .015" off from the outside jaws to the depth rod. This is a minor point but it demonstrates why they need to be zeroed before using. Most of us don't bother having our tools calibrated. The next best (and a whole lot cheaper) thing is to keep some sort of gages on hand to verify the readings.

[DLCTEX]

Dial caliper and micrometers in a drawer right behind me. Dale

[theperfessor]

I check our school's dial and vernier calipers against the gage blocks that came with our 0-6 outside mike sets. You can also get a relatively inexpensive set of gage blocks that are accurate enough for setting shop mikes and calipers from several sources (ENCO, MSC, etc.). Pool the cost with your friends. Gage blocks are tough and don't get out of adjustment - which is why they are used to calibrate all adjustable measuring tools.

The biggest problem I have with keeping dial calipers working in a school shop environment is due to the kids slamming the movable jaw shut into the fixed jaw. This doesn't normally hurt a vernier caliper but I've seen the dial needles fly off and spin around inside the case like a helicopter rotor from the sudden stop!

As to precision level and how finely you can read a mike/caliper - don't confuse the fact that you can read an instrument to .001 or .0001 or whatever with the fact that if your measurement techniques are deficient the reading can be very precise - and very, very wrong. Some tools, such as smaller-sized outside mikes, can be used very easily and can give very consistent (and accurate) readings. Calipers by their very design are not capable of giving as consistently accurate readings as mikes (no micrometer screw to enhance the resolution).

When formerly employed in heavy industry I used a 144" vernier beam caliper to check bore centers in large gear boxes and power transmission cases. We would support the beam on enough parallels to keep it flat and level, otherwise it would sag one way or the other and flex the jaws inward or outward enough to throw the readings out of the window. It would still read to .001, (the precision stayed the same) but the accuracy (how close the reading is to the true size of the part) was way off. It's all technique and recognizing the limitations of any tool.

Good measurement comes down to three things:

(1) Accuracy - how closely the reading on the tool is to the true size of a feature. If the mike reads .375 when you measure a .375 gage block then it is accurate. (Tip/note: Gage blocks let you check at several sizes within a given range to check for non-linear readings.)

(2) Precision - How finely you can distinguish size increments. A mike that reads to .0001 is more precise (but not necessarily more accurate, see (1) above) than a mike that only reads down to .001.

(3) Technique - How the tool is used. If you use an outside mike with a gorilla fist to read a soft lead bullet and then report your readings down to the .0001 level and think that it is an accurate reading then you are kidding yourself.

Sorry to ramble on...

[floodgate]

One other point: I ALWAYS park my 0" - 1" mikes and my dial and vernier calipers with the jaws open by a few thousandths, NEVER jammed tightly closed. I've never seen this mentioned, but I've always had a "feeling" that major temperature changes (my shop gets very cold in winter, and hot in summer, when I'm not in it and using heater or ventilation) could "spring" a tightly closed one a bit.

floodgate

[grumpy one]

Doug, not leaving micrometers screwed shut is a standard point made when teaching apprentices etc. Because of the rigidity of the device - which is essential to its accuracy - temperature changes might otherwise cause heavy loads on the adjustment screw and distortion of it or the nut - the key elements determining accuracy. However no harm is done by leaving calipers fully closed so long as they are not locked. Any expansion just causes the slide to move slightly.

[Ed Barrett]

I keep a digital caliper on the bench the micrometers are in boxes in a cabinet about 10 feet away. Close enough if I need something a little finer.

[floodgate]

Geoff:

The vernier calipers I use most DO have the locking bar; it would probably slip under load, but I still am more comfortable leaving them slightly open. And in its leather case in the drawer, at least a lttle protection if something should slip out of my grip and fall on it. The 0" - 1'" Mitutoyo also lives in its rigid plastic box in the lathe drawer when not in actual use. These "moves"have just become automatic with me; a benefit as my short-term memory increasingly has lapses (turning 77 this weekend); "muscle-memory" still works fine - if I don't stop and analyze it too much!

Doug

[Idaho Sharpshooter]

I cast in a 10-x20 shop, and my lovely wiefe bought me a propane heater and a 40lb bottle for Christmas. 5 minutes and it is t-shirt weather inside. I have a digital caliper about 3 feet away from the pot.

I also made up two 24" 1"x4"'s with four rows of 25 holes in each one. I fill a block, reload and reflux the post and check bullets. Saves a lot of grousing later when the pot is cold and I am culling.

Rich

[grumpy one]

Doug, if you are still successfully using vernier calipers at 77 you have a lot to be thankful for. In my experience most people switch to dial calipers sometime in their late 40s. I tried it, but it didn't work. First, an associate I was working with on a car restoration project was so fascinated by the 8" Mitutoyo dial caliper that he would stand there for several minutes repeatedly slamming it shut and seeing how closely it came back to zero. Of course he split the tiny ruby bearing that holds the moving pointer. I had it replaced, but then I dropped the thing and broke the replacement ruby bearing. Since then I use a vernier caliper for a first approximation, and the right sized micrometer if it matters. I can still see the vernier so far (I'm 62) but I can foresee the time when I'll step up my use of micrometers. Of course there is still a vernier involved, but only for ten-thousandths.

[floodgate]

Geoff:

Well, I won't be 77 for a couple of days yet; but I DO have to hold it under the lamp or out in bright sunlight to read the vernier.

Several years ago, a friend who was into BP bench-resting with some pretty stuffy types borrowed a couple of 2" - 3" "super-el-cheapo" Chinese mikes I had picked up at one of those itinerant junk-tool-mobiles, and used them to clamp his spotting scope base to the bench. He got into a lot of "interesting" conversations with them. Funny thing is, when returned, they still checked out OK with the 2" standard. I've still got one of them around somewhere, and put the other in the tool box at our gas engine and tractor club workshop.

Doug