Digital Calipers

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Well-Known Member
Jan 25, 2009
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Hi all,

I'm in the market to buy a set of digital calipers. I need them to measure at least 8" accurately. I have several I am looking at, and want opinions.

Set One

Set Two

Set Three

I am looking to keep the price at about $35. The reason I want the digital calipers is the accuracy that I can get from them, as opposed to manual calipers (no dial) which I could just as easily replace with a ruler and/or a tape measure.

I want to use these calipers with my drill press for measuring my circle cutter radius/diameter, for when I get my lathe, and other misc. rocketry-related tasks.

Thanks in advance.

I HAD a set of those. Not exactly the same but sure looked it. I bought them from someone on Ebay and it was very precise. I use the past tense because someone :)p ) bumped them off the bench one day and after trying for a week to get it to work, tossed it in the trash. numbers were are backwords and blinking. So, Although I like them, I don't know if a dial caliper would be more durable. I suppose in either case dropping a precision instrument on a concrete floor would produce un favorable results:D
I have used a 6" set for a long time in both my school's machine shop and here at home for auto work and rockets. They are precise and the 6" set was $18. For the price they cannot be beat. At school we had a rod that is 5.841 inches long - measured by a laser thingy that the ME's have. I go and check my calipers agains that about once every three months. They are .001 accurate every time. Worth the investment and you will find many uses for them. I have dropped them a few times on carpet, but not on concrete. I spazzed out once and dropped a set of gauge rods .001 to 1.500 inches in increments of .001 on the floor. Talk about 1500 card pick up :)

I spazzed out once and dropped a set of gauge rods .001 to 1.500 inches in increments of .001 on the floor. Talk about 1500 card pick up

... oooohhhhhh!! that's an image .... shudder!!

(in your "STL Rocketry" I thought STL == Slower Than Light :)

What brand are yours and where did you get them? (And when?)

The $18 one was on sale at Harbor Freight. I got mine a long time ago. It even has a data record function that you can hook up to a computer and a three pin output - haven't figured it out yet but really don't need it. Id on't know the brand, hold on...
No brand, just says Electronic Digital Caliper.

Says it was made in China, but no brand at all... :(

Wow... I just did search on Harbor Freight for Digital Calipers and it came up with what looks to be your set, but minus the output logging feature. I don't really need that anyway. The prices are VERY reasonable!

Harbor Freight has some cool products, this is a good one. I don't get the data logging computer connection. Unless you have thousands of things to measure for quality control and want the data stored for analysis then most people won't use it. I don't want my caliper with an umbilical cord attached.

But I guess if you are mass producing something and want the standard deviation in size then that's the way to go. Pay someone to measure every part.

I have never liked dial calipers or micrometers - I like the big digital display :)

The calipers are an indispensible tool for me when I'm doing EX work when you want to know chamber measurements accurately. I never take it to the houses I build - I would get called a few not so nice names...and it wouldn't matter, most of my guys don't even read to the 1/16, just 1/8 heavy and 1/8 light. A couple still count numbers of tick marks....(Hey, it's 5 marks past 6 inches.) Some people....amazing stuff is level and true after they build it..Anyway, I'm digressing and need to clean my closet.

Anything...dial or digital better than the old vernier calipers!

Reminds me too much of a slide rule! GAWD I hated those things!

Slide rule? Some tests I have taken ban calculators but I have always got my trusty slide rule handy :) I get wierd geeky looks but it works... In one computer lab we have a 20 foot slide rule on the wall. It screams "Geeks R Us"
My mother had her slide rule from when she was growing up, and I learned to use it as well. I well remember using it on "no calculators allowed" exams in high school and in college. It's true sign of geekdom in this day and age of digital everything (my wife even has a digital pedometer that tells her how far she has walked during the day!), but by golly, it saved my bacon on a wide variety of tests!

Heck, This is the only kind I can read!:D

Just not too portable.

jason .heres a good one .I have 2 of the 6"type at work one at home .
along with a 6" brown and sharpe at work ($ 80)

it's plenty accurate.and comes with a spare battery

curious...why the 8 " rather than the 6"?.you looking at sono tubes again? heh
Yep! Lookin' at sonotubes again!

I'm actually building a rocket based on the 8" by 48" sono tube and would need the 8" for it to measure CR's and MMT holes.

Thanks stymye - I'll likely be buying from Harbor Freight. They are the cheapest I have found for 8" digital calipers.

Watch out for those 8" sonotubes as the dimension is NOMINAL, not exact. You could end up with one that has an ID of 8.125 or even 7.825. Just a heads up!
I might look into getting those 8 dollar ones... Look good for my uses.
Rotf..Sandman, now thats cool !

I've got a normal sized one, but dang..I could use that one easily. 8)

I personally think anyone whom does Scale Rocketry needs to have a Slide Rule in their collection, simply because it was this simple tool that helped us land men on the moon.


Some AV guy at a school I work at gave me that. They don't teach "slide rule" anymore!

I thought it was cool!

I also got an "OLD!" globe of the moon with "proposed" Apollo landing sites.

The globe is identical to the one on the K-36 Saturn V box!

They were gonna throw it away! It has a dent in it....sooooo!