Digital caliper

[will]

I have been involved with restoring/fixing an old Trek bike and a Schwinn bike. A lot of the measurements for bike stuff is metric. I had been using a fractional dial caliper, then converting the measurement to metric.

Well - I dropped the caliper and cracked the dial bezel, the caliper also felt a little stiff. I did not trust it any more. This is a caliper I bought from ENCO a number of years back, probably under $20.

Went online and found a Digital Caliper for $12.49. Stainless steel. Great because it can go from fractional to metric with a push of a button. Now, I am not going to be making any parts with a tolerance of .001. I also should point out it is not a Starrett, but for $12.49 and someone who can work with a few thousands tolerance, not a bad deal. I have checked it out against some items that I know the diameter of and it does seem to be accurate.

Right now, the most important feature for me is the conversion it does..

 

[wquiles]

+1

When I am machining parts, I only trust my vernier, "analog", 50-division Starrett caliper, but for quick checks, specially when going back and forth between inches and metric, I also have a cheap digital caliper :D

Of course, another option when needing both inches/metric (at least for OD measurements) is my Starrett inch/metric N.123 E&M

I know it is a little bit "sacrilegious" but I did cut my larger inch/metric model to a more "handy" size/weight, and this is the one I now use like 90%+ of the time:

Will

 

[will]

Got to love vernier calipers.....

( what do you mean, line up the lines on the two scales, only one actually lines up )

 

[Lynx_Arc]

I have a cheap digital one I got from harbor freight, it is slightly buggy at times it floats off into growing numbers but most of the time it works well and has a mm/inch button to change settings takes a single AG13 battery easy enough to find and does the job quick. I think I paid $10 for it on sale. I would love to have a name brand digital caliper but $100+ not in my budget for the very few times I would use it.

 

[moderator007]

The cheap calipers work great for me. They are not as nice as my mitutoyo Absolute but are dependable with in .001 or so. One thing that I did notice about the cheaper calipers is that if the caliper seems to loose zero alot then replacing the battery usually solves the problem. They do tend to loose zero sometimes but when the battery is low it seems they will loose zero quite often. I always zero mine before taking a measurement to make sure there set.

With the mitutoyo's, once you set absolute zero its there I guess to the battery runs dead, don't really know. I have had them about 6 months and have never had to rezero them. I don't mean to sound like the cheaper calipers won't do a good job, they most certainly can within exceptable range. But once you have used a high quality caliper you will not want anything else. So much easier to operate and accurate. I bid and won mine on a ebay auction brand new for $76.00 and $3.15 shipping. It took alot of patience. They are well worth the extra money. I own 5 cheaper calipers and always reach for the mitutoyo.
You can look up ebay item #290764614397 or #300770827055. This guy doesn't respond to emails (buyer beware) but does ship the item quickly and as described new. I have purchased 2 from this seller without problems besides no communication. I think that there not being seen that much because the seller doesn't use the word digital in his item description.

 

[precisionworks]

Some of the less costly digitals work OK & some don't. For $12.49 you can buy another one when the first one goes south. Battery life is often measured in weeks if the battery is left in the caliper (Mitu's run 2-3 years with 8 hours of daily use). Just be sure to remove the battery when you turn out the lights at the end of the day.

 

[will]

Some of the less costly digitals work OK & some don't. For $12.49 you can buy another one when the first one goes south. Battery life is often measured in weeks if the battery is left in the caliper (Mitu's run 2-3 years with 8 hours of daily use). Just be sure to remove the battery when you turn out the lights at the end of the day.

Mine came with an extra LR44 battery, it turns off automatically after a few minutes. Here again, not used for business, just very casual personal use.

 

[Lynx_Arc]

Mine came with an extra LR44 battery, it turns off automatically after a few minutes. Here again, not used for business, just very casual personal use.

I recently put another battery in mine after about 5 years, it too turns off after a few minutes not sure how long maybe 5 to 10 or so and I can buy the LR44/AG13 batteries for a dime each in bulk off ebay... 20/$2 if you look long enough.

 

[moderator007]

According to what I read when I was researching for a good caliper, the caliper is not actual off when the display is not lit. The caliper is still reading position and drawing power the display is just off. The way to test this is turn the caliper off then move it a inch or so, turn it on see if it reads a inch or so. If it does it is still reading position while it is off. According to what I read again, the cheaper calipers used almost twice the resting energy that the mitutoyo used. In (on) operation there was not as big of difference if I remember correctly. The battery you use can also play a big part. The SR44 has a superior discharge curve to the cheaper LR44. I have not tested battery life personal on both just read someone else findings. Like barry said, the best way to save battery life is take it out when not in use.

Found the link: Caliper Battery Life

 

[will]

My display turns on as soon as there is any movement. It seems to me that I have a bunch of LR44 batteries around here. My personal usage just would not justify spending spending lots of money. I do have very good 1 inch and 2 inch Micrometers, which I do use for critical measurements.

 

[Lynx_Arc]

According to what I read when I was researching for a good caliper, the caliper is not actual off when the display is not lit. The caliper is still reading position and drawing power the display is just off. The way to test this is turn the caliper off then move it a inch or so, turn it on see if it reads a inch or so. If it does it is still reading position while it is off. According to what I read again, the cheaper calipers used almost twice the resting energy that the mitutoyo used. In (on) operation there was not as big of difference if I remember correctly. The battery you use can also play a big part. The SR44 has a superior discharge curve to the cheaper LR44. I have not tested battery life personal on both just read someone else findings. Like barry said, the best way to save battery life is take it out when not in use.

Found the link: Caliper Battery Life

The cheap one I have does go off after awhile you have to hit the ON button to turn it back on it won't come on with movement.

 

[moderator007]

The cheap one I have does go off after awhile you have to hit the ON button to turn it back on it won't come on with movement.

I do have some that stay off some come on with movement. They are still drawing power. If it stays off with movement, move it a inch or so while off then turn it on. Does it still read about a inch. It was reading the movement if it does. Using power while moving and waiting for movement.

If it comes on with movement then it is idle monitoring for movement but still using power. Same as the ones that stay off but it turns the display on when it senses movement. The ones that stay off are only powering down the display, their still working you just can't see it because the display is off.

 

[precisionworks]

According to what I read when I was researching for a good caliper, the caliper is not actual off when the display is not lit. The caliper is still reading position and drawing power the display is just off.

+1

The spare digital I bought came from MSC & was SPI model 14-792-6. They still carry that one at $50 retail & $25 on sale. I mistakenly thought that the SPI name & the higher price made it better than the $10 models. My bad.

The battery would not last 30 days when left in the caliper. Caliper was stored in the case & kept in a temp controlled office. Long Island Indicator claims average batt life in a Mitu is 1277 days (3.5 years) but let's figure really conservatively and call it 730 days (2.0 years).

The MSC clunker would eat 24 batteries for every one used by the Mitu. Found a nearly new Starrett 102A-6 for $75 and it has never gone through even the first battery. Price is higher, yes, but cost is close to zero. It would sell today for $75 (probably more) so cost for using this caliper for five years is $0.00. It feels just as good as it looks so I picked up the 9" & the 12" models at bargain prices, either on eBay or on one of the forums.

No tools are higher priced than Mitu & Starrett & nothing else has a lower net cost. I like tools that cost nothing so I keep spending way too much for the ones that cost so little :)

http://www.starrett.com/metrology/product-detail?k=120A-6

 

[will]

I have had mine for 2 months now, still the original battery. I'll leave it in and see how long it lasts. If it is a year or so, I won't take it out.

I suspect there is a wide range of inexpensive digital calipers, some better than others.

My own feeling on this - If you are in the business of making things using a lathe, milling machines, drill presses etc.. the best is a quality, oil proof digital caliper.

If you aren't making things. just figuring out what you have for various hobbies, and you are not using it on a daily basis - then an inexpensive digital caliper fits the bill...

 

[Lynx_Arc]

My caliper is a Cen-Tech brand, does yours have an "ON" button?

 

[will]

Mine is a 'no name' brand. inch/mm button on top of display, on/off and zero on bottom of display.

 

[Codiak]

I have the same digital unit for HarborFreight and Menards... both over a year old... both using the original battery... and both under $20

 

[KC2IXE]

I've had a mitutoyo Absolute solar unit for oh, 10-15 years now, works fine. As for not trusting it, when I need more than it will deliver, that's what Mics are for. Can't tell you how many 0-1 Mics I own (Literally, I cant, I've run across too many 'you have to buy the whole toolbox to get X', and then there was the day I came across the garage sale with brand new Miti 0-1 mechanical digital mics - they wanted $5. Bought all 6 sets they had. I have mics up to 6", which is as large as I go - do need some longer units someday

 

[precisionworks]

If you are in the business of making things using a lathe, milling machines, drill presses etc.. the best is a quality, oil proof digital caliper.

Lightweight calipers (dial, digital, vernier) are good enough for wide tolerance work. Each of those types is reliable to + & - 0.001" (0.025mm). For lot of work plus or minus 1 is within the accepted or called out tolerance. When the tolerance is any amount less than that the calipers should stay in the drawer & a more accurate tool is required.

Heavy frame verniers, micrometers, inside mics, etc. are the tools of choice when critical dimensions have to be hit dead on. Imagine turning down an electric motor shaft for a bearing press fit & using the most expensive digical in the world ... only to discover that you turned the diameter .001" too small & the bearing drops on with a thud.

That happened at a shop because a newer machinist insisted that his $$$ digital was better than anything else. Motor was 500 hp & weighed about 2000# (roughly 1000 kg). Shaft was typical for that frame, just under 3" (75mm) IIRC. The new guy extracted the rotor without dropping it, got in in the lathe, carefully turned down the shaft for the correct interference fit. A couple of us noticed he seemed to be squeezing the jaws pretty hard & that might be why he went way too far. Shop manager came over with his Starrett mic, took a few measurements & asked the machinist if he had any experience with the flame spray lathe. Nope he said, that's the worst job in the shop (and it was).

He got really good at flame spray during the next few months :nana: Heard he left & choose another career path.

 

[KC2IXE]

Lightweight calipers (dial, digital, vernier) are good enough for wide tolerance work. Each of those types is reliable to + & - 0.001" (0.025mm). For lot of work plus or minus 1 is within the accepted or called out tolerance. When the tolerance is any amount less than that the calipers should stay in the drawer & a more accurate tool is required.

...snip....

I'd bet that 99% of the work out there is +- .001 or more. Heck, I'd bet a lot of work has .005 or more...