Chinese dial indicators

[LLCoolBeans]

I have several Chinese made dial indicators branded with different names.

These are a huge savings over the domestic and high end Japanese/euro imports and I have yet to find much fault with them. They don't look quite as nice as the real ones and the bezels don't rotate as freely, but they are as accurate as they claim to be.

Am I missing something? Can someone tell me why I should not be buying these?

 

[precisionworks]

Can someone tell me why I should not be buying these?

You may get lucky & find one that works for quite a while, or the indicator hand may fall off at the second use (happened to me with a Fowler brand). There's quite a bit of precision fitting, starting with the plunger to bore fit, plus a gear train & clock spring that (should) ride on jeweled bearings.

If you watch for specials, you can pick up Mitu's for under $50, and I bought a number of Federal-Mahr indicators for $29 each (Penn Tool sale flyer).

It all depends on what your expectations are. If you use them for depth of cut indicators or depth of feed indicators (on the lathe) they need to be trust worthy. Decent indicators allow you to advance the tool half a thousandth, or a quarter thousandth, on the radius, which makes close fits easier to achieve. They are also more immune to machine vibration.

 

[Superdave]

I bought one a few years ago from Sears for my automotive work. It has held up well through several engine builds and other random projects. I think it was only around $40 or so.. but i had to make my own magnetic mount.

 

[old4570]

I got the good stuff , I got the cheap stuff , all I can complain about is getting dud batteries off Flea-Bay .

Now I dont bother putting the side cover on for the batt on my digital calipers as the batt just dont last long ..

Best investment - Mitutoyo Digital Micrometer :naughty: Im so glad I got this when offered , also have a Mitutoyo Dial Calipers , MTI plastic Dial calipers , Chinese digital calipers [ Plastic ] + Chinese SS digital caliper ..

Its all good so far , expt for the Flea-Bay Batt's .

The dial indicators , sooo many to chose from , $$ and whats your idea of Cheap . Mitutoyo ones cost over $100 here in Oz , all machine tools are freaky expensive in the shops here ... Why I gave up on owning a lathe , FKN expensive tools , + no Flea-bay back then ...

Now with Ebay , im considering owning a lathe again .

 

[Ray1968]

I used to run the calibration lab at the aerospace company I work at. There were many times a guy would bring in a cheapie Chinese made indicator, mic, caliper etc., and they wouldn't pass calibration.

I'd have to give it back to them and say, "Sorry, can't certify it. You gotta take it home". Man, some of them would get PISSED! I'd have to sit there and show them how the thing wouldn't repeat, hold tolerance over the range, etc. They'd still go stomping off to the QC manager demanding I put a sticker on their tool. He'd tell 'em the same thing. Take it home.

Too bad, so sad, LOL.

 

[gadget_lover]

That's good to know Ray. I've done spot checks on mine, and they have passed MY simple checks, but I did not check them across the whole range, nor did I check for repeatability on more than a couple of spots.

Of course, all the dial indicators have had quality certificates, so you just KNOW that they are all perfect.


Daniel

 

[modamag]

It all depends on what you use them for.

I have a friend who swear by the chinese indicator (even HF ones). But he works mostly with wood and eyeball 1/16th tolerance.

The only thing I have to complain about these is the rate at which they eats batteries. I had used them on my Shumatech DRO kit and I'll have to replace the batteries every 1-3 months.
Here's a great article Bill wrote on these

If you plan to do metal work, you can get a brand new Mitutoyo for ~$80, well worth the money. Keep in mind the carbide tips used for quick scribing will save you hours.

 

[precisionworks]

get a brand new Mitutoyo

IMO, nothing draws less current than the Mitu digitals. I started with a 6", went to an 8", bought the coolant proof version, and went back to a 6" (which has shorter jaws that will get into tighter places). Battery life is measured in months, even if you forget to turn the display off for a few days or a week.

Also, every Mitu caliper & every Mitu digital mic use the same battery, so one or two spares is plenty.

 

[darkzero]

IMO, nothing draws less current than the Mitu digitals. I started with a 6", went to an 8", bought the coolant proof version, and went back to a 6" (which has shorter jaws that will get into tighter places). Battery life is measured in months, even if you forget to turn the display off for a few days or a week.

I can agree with that. I have had my 6" coolant proof version for years & I can only remember changing the batteries a few times. Mine does not have a on off button though, it auto shutsoff. This last battery change I used those cheap China batteries & I do notice a difference in battery life. the "B" is on already.

I have a HF 4" that I keep in the tool box. It eats batteries like crazy but I use the cheap China batteries in it & probably mainly cause I forget to turn it off. It does not have the auto shutdown feature.

My 6" coolant proof Mitu always comes back to zero. If it doesn't, I know there's probably something on the jaws, a quick wipe & back to zero. My HF 4" constantly has to be rezero'd which can be annoying. Zero it, open & close it, then reads -0. My HF 6" was the same way (sold it here when I got the Mitu).

Because I'm not happy with the HF 4" I'm thinking about picking up another set of Mitu calipers to keep by the lathe. I was thinking to get another set of the 6" coolant proof but now I'm thinking to get a set of Mitu dial calipers.

I've got a HF dial that I used when working on engines. It didn't get used that much but it's more than 5 years old. I used it today with the lathe & it seems like it doesn't always come back to zero. I could be wrong though & it might just be my error. I've been looking at getting a Mitu 2416S & 2416SB but I originally was eyeing out digital Mitu indicators on ebay.

I've read a bit here & there on the differences between digital & dial. I wouldn't be buying the top of the line digital Mitu indicator & for what I do I don't need critial measurements. Any suggestions on digital & dial?

 

[Dan FO]

All of mine are American made dial, I don't have a digital so I can't comment. L. S. Starrett and Brown & Ssarpe here.

 

[precisionworks]

It's hard to beat the Mitu 504 Series:
http://www.mitutoyo.com/TerminalMerchandisingGroup.aspx?group=1738

That said, there is one issue that will eventually come up with any dial caliper used near the mill or lathe. A tiny, almost invisible chip will lodge between the rack & the pinion that drives the indicator hand. It takes probably half an hour to take out the tiny screws that hold the rack in place, brush & blow it out, clean the pinion gear, and assemble it so the hand points where it should (with jaws closed). The digital eliminates this, as the encoder is built into the tool, and the reader head does not work by physical contact. It's really hard to mess up a digital with chips, dust, dirt, etc., but water or coolant can damage those that aren't IP65 rated.

 

[PEU]

IMO, nothing draws less current than the Mitu digitals. I started with a 6", went to an 8", bought the coolant proof version, and went back to a 6" (which has shorter jaws that will get into tighter places). Battery life is measured in months, even if you forget to turn the display off for a few days or a week.

Also, every Mitu caliper & every Mitu digital mic use the same battery, so one or two spares is plenty.

The battery in the first digital caliper (chinese) I ever bought last months even when forgot to turn it off leaving it on for the whole weekend. The ones I purchased afterwards even having auto-off feature suck at battery life...


Pablo

 

[gadget_lover]

Part of the battrey life problem is the batteries. Really!

The small button cells can be one of several different chemistry. The most common is the LR44, a simple alkaline mixture similar to what you get in a cheap "heavy duty' that is included in a new toy. These batteries have a short shelf life (a few years) and voltage drops quickly under constant drain. A couple of months and they are dead.

The venerable SR44 is silver oxide, and it has 160mah at 1.5 ma. It has a shelf life of many years. It's discharge curve is fairly flat, so you will see much longer USABLE life.

I bought some SR44's just for the calipers I use most. The ones I seldom use have LR44s at 20 cents a piece.

Daniel

 

[precisionworks]

Part of the battery life problem is the batteries

I agree that better types of batteries yield longer battey life, but looking further, similar battery types can have greatly different life in different calipers.

All Mitu calipers & mics use the SR44 battery, and have a stated battery life of 3.5 years (20,000 hours) - this assumes you turn the unit off after use, or that it has auto off.

Starrett is no slouch in metrology, but their battery life is short by comparison, with a 3,500 hour rating. I cannot tell you how often this has been mentioned on various forums.

FWIW, the Practical Machinists forum does have a new Metrology Section:

http://www.practicalmachinist.com/vb/forumdisplay.php?f=45

 

[StrikerDown]

About a month ago I picked up a HF Dig Caliper, Put in the battery made a couple mesurements, turnded it off (it is auto off) used it a coulpe times over the last couple weeks,then yesterday the batt was dead. That's poor life in anybodys book.

The replacement batt will be taken out after use now, used it on and off all day yesterday and some this morning, took it out again! There must be some drain when off to keep it set to measure inches because every time I replace the batt it defaults to mm.

At first I thought it might be the instruction book that was stored in the case but I wasn't able to make it turn on the unit by trying to close it on the booklet.

Next time I spend the big bucks!

 

[darkzero]

That said, there is one issue that will eventually come up with any dial caliper used near the mill or lathe. A tiny, almost invisible chip will lodge between the rack & the pinion that drives the indicator hand. It takes probably half an hour to take out the tiny screws that hold the rack in place, brush & blow it out, clean the pinion gear, and assemble it so the hand points where it should (with jaws closed). The digital eliminates this, as the encoder is built into the tool, and the reader head does not work by physical contact. It's really hard to mess up a digital with chips, dust, dirt, etc., but water or coolant can damage those that aren't IP65 rated.

Thanks. I picked up another set Mitu Absolute Coolant Proof cailpers today on ebay to replace my HF 4" to keep by the lathe. The one I currently own I got years ago is IP65. The one I got used today is also IP65. I noticed there are IP66 & IP67 that cost a lot more. Just browsing, I've only seen this rating on Mitus, on micrometers too. I'm assuming IP65 is old but I'm not concerened about it. What are these IP ratings & is it an industry standard or only for Mitus?

 

[precisionworks]

Ingress Protection (I P) Ratings are a widely accepted Euro standard that denotes the degree of protection an enclosure provides - the caliper itself is the enclosure in this case, but it can also be used for switch boxes, motors, etc.

IP First number - Protection against solid objects

0 No protection.

1 Protected against solid objects up to 50mm, e.g. accidental touch by hands.

2 Protected against solid objects up to 12mm, e.g. fingers.

3 Protected against solid objects over 2.5mm (tools and wires).

4 Protected against solid objects over 1mm (tools, wire, and small wires).

5 Protected against dust limited ingress (no harmful deposit).

6 Totally protected against dust.

IP Second number - Protection against liquids

0 No protection.

1 Protection against vertically falling drops of water e.g. condensation.

2 Protection against direct sprays of water up to 15° from the vertical.

3 Protected against direct sprays of water up to 60° from the vertical.

4 Protection against water sprayed from all directions - limited ingress permitted.

5 Protected against low pressure jets of water from all directions - limited ingress.

6 Protected against low pressure jets of water, e.g. for use on ship decks - limited ingress permitted.

7 Protected against the effect of immersion between 15cm and 1m.

8 Protects against long periods of immersion under pressure.

For North American use, the NEMA (National Electrical Manufacturers Assn) Standards are more commonly used ... but there is no direct correlation between NEMA & IP

Two common NEMA standards for VFD enclosures are NEMA 1, and NEMA 4X. The NEMA 1 enclosure is fully "fingerproof" on all sides, but provides no liquid protection. The NEMA 4X is essentially dustproof & waterproof, which is why that enclosure is often used around lathes, mills, grinders, etc.

NEMA 1 = IP 10

NEMA 4X = IP 56

 

[darkzero]

Thanks Barry. Always enjoy all the info you provide. I consider you the human machining knowledge base. :thumbsup:

Another question. I just got a couple of 2416 Mitu dial indicators on ebay but they are the jeweled versions with the -10 in the p/n. Sorry if this is a dumb question but what's the difference? Is it simliar to watches?

EDIT: Googled & found my answer.

 

[precisionworks]

they are the jeweled versions

Nice catch, Will. You do know how to give a person tool envy:thumbsup:

My understanding is that all the Mitu Shockproof models have jeweled bearings. They are my favorite dial indicator, and get more respect (and better treatment) than the other brands.