Buying new micrometers

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Alberto-sp

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Hello.

I was a cheap person, but at the beginning I wasn´t very wise (and probaly not now) and I didn´t know that I was to get so involved in machining. So I´m going to buy new micrometers. 0-25, 25-50 and 50-75mm. I have 2 options 0,01 or 0,001mm. For hobby machining is worth the 0,001?

I have heard good opinions about the brand Insize, do you know it?. I know, Mitutoyo, tesa and that brands are very good, but not my budget.

Thank you.
 
.01 should be plenty fine. My chart says .01mm is .0004". You usually olny need to get to 4-5 tenths on a critical part and you can probably estimate that looking at markings. Most of your hobby machining will be to a couple of thousands. With that said if there is not much difference in price, or you can get better brand mics used at a good price, I would (and have) done that. You will never go wrong buying more accurate equipment if you can find and afford it. I don't have a 0-1" tenths mic. Lots of time I would like it for camparison, but for now I just estimate.
 
In general, if you use calipers you can do work down to around +/-0.01mm. The purpose of using a micrometer is that you can get more accurate readings, so I would recommend 0.001mm. Inexpensive micrometers, or used ones that haven't been abused should be readily available, there is no penalty for having the extra accuracy and then determine what level of accuracy you need. I am a hobbyist but often I do work where I need accurate dimensions that exceed the resolution of a caliper. The cost difference for the increased accuracy in for a micrometer is nominal, there is also the factor that there is resolution (what it will read to) and accuracy what it will reliably measure to.
 
If you are doing bearing seats on a shaft, couplings, etc that need a specific fit to function properly, then you might want the 0.001mm micrometer in at least the 0-25mm size. A typical tolerance for a 15mm bearing seat is 0.001 to 0.012mm, that can be difficult to estimate with a 0.01mm reading micrometer.
 
Thanks for your answers. Yes, the problem with the old micrometer came with a proyect involving shafts and bearings.

And I'm thinking buying a new dial indicator. Wich one is more useful? The drop one or the lever one? I already have both (0,01mm), but cheap so I want a good one. If I have to choose only one, lever or drop? And wich resolution? Because more resolution implies less range.

Thank you!
 
If I could only buy one indicator, I would probably buy a lever style indicator in 0.01mm. My first lever style was 0.0005” resolution, and my second one is 0.0001”, but I find I rarely use that one, I prefer the greater range and less sensitivity of the first. My drop indicators are mostly used for dialing in stock on the lathe, but you could use other means of getting it close enough that you could switch over to the test indicator for the final dialing in. It’s tough using a drop indicator on the mill, the lever style is much more useful there, so I would probably go that route in your shoes.

I don’t know if Ebay is an option where you live, but I bought all my metric Mitutoyo micrometers on Ebay over the years for great prices and they have been in great condition. With Ebay doing global shipping, you might be able to get some good deals on sales in the States if the seller is willing to sell overseas. Most people here don’t want metric instruments, so they tend to go cheaper than inch based. The only disadvantage of metric indicators here is the yellow face they put on to differentiate them from the inch based ones in case that is an issue for you.
 
I've got a set of Starret mics, 1, 2, & 3" that have marks @ .0005" and I can estimate pretty good in-between. I've got the gage blocks for them and they stay dead on. My Mitutoyo 1" has the same markings and also a mechanical display that is very good for seeing .001 and guessing at how far it went to the next but the spindle reading is much easier to guestimate. I've never had a .0001 mic so I am making the assumption that they take 10 times the turns to advance? That could be a drag if you needed to make a very big move.
 
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