First threads!

devils4ever said:
I agree totally that the wires are a big PITA. The are cheap and they do work and I'll keep them for when I need to go bigger than 1" diameter or if I ever decide to cut Acme threads.

For anyone using wires, these are the charts that came with my Browne & Sharpe Thread Pitch Diameter Wire Set. As you can see, it will do both Imperial and Metric as well as Acme threads.

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First, the acme chart is awsome! I'll have to see if my B&S set came with any cards! Second, I was really wondering what the 'add' column in the chart meant! Its nice that this one says it!
 
raven7usa said:
Here's an easy way to use thread wires.
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I don't remember which youtuber mentioned it at one point (maybe buildsomethingcool?), but you have to be careful doing that. If the wires 'flex in any way as a result of that, it'll make your measurement look larger and result in the measurement being larger than it is, and likely resulting in an overcut.
 
I don't use thread wires, so can't comment on its effectiveness, but I recently saw a youtuber use a small dab of grease to hold the wires in place while he positioned them and fidgeted with his micrometer. It seemed to work well for him.

Tom
 
I've heard of people using the styrofoam shipping peanuts to hold the wires (stick them into the peanut).
 
I do nearly all my measuring with wires. With some practice I certainly don't find them as difficult to use as most people claim. Certainly not as easy as a mic, but I never have issues with it. It also allows me to use my normal mic, calibrated against standards. You can't do that with a thread mic unless you have a thread master (which I don't).

But from a convenience factor, thread mics are great.

I worked for a while in a metrology lab and the gold standard is thread Go-NoGo gages. Very expensive to buy them for all your thread sizes and all tolerance classes. We probably had 15 sets of rings for each size of thread for various tolerance classes (ASME, DIN, ISO, etc). When I do production jobs, I will invest in the gages required for the job if the quantity is over a couple dozen. Very reliable to check that way.
 
I also have found them less annoying with practice; basically tell myself I'm not digging through the chips even one more time, so get it right!
Tim
 
I cut a 3/8"-16 thread on my lathe and had a chance to use my new Shars thread mic. According to the Theoretical Machinist.com's thread calculator, the pitch diameter range for this thread is: 0.3287" to 0.3331". I measured 0.3312" with my Shars thread mic. It fit the matching thread perfectly! I must say the thread mic is definitely easier to use than the wires, but it still requires a little finesse in using.

Also, I confirmed that the 0.75/TPI equation works. In this case, 0.75/16 = 0.0469". I advanced my compound by 0.044". Like previously mentioned, use this equation as a guideline and keep measuring as you get close!

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Good looking threads. The biggest problem I have with the Shars TM is setting the zero when you change the anvils. You have to ensure than when you ratchet the TM to zero, it actually reads zero - if not, you have to adjust the bottom anvil and retest.
 
SLK001 said:
Good looking threads. The biggest problem I have with the Shars TM is setting the zero when you change the anvils. You have to ensure than when you ratchet the TM to zero, it actually reads zero - if not, you have to adjust the bottom anvil and retest.
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Thanks!

Yes, that's true.

Isn't that true of all thread mics that have changeable anvils? I know Starrett makes thread mics with fixed anvils which require you to buy a full set for all the thread pitches. Each one is over $350.
 
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