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# Request help with acme(?) thread ID

#1
01-15-19, 02:14 PM
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Request help with acme(?) thread ID

I'm looking to determine the thread sizing of this inexpensive WEN 2-axis vice. Was hoping someone could give a good guess based on just the images I posted of the thread pitch measurements and the fact that major diameter is .466"/11.88mm. Thread pitch seems to be a bit in-the-wind and not ending on-the-tooth.

Best guess is it's a general purpose acme 2G thread. Looking at both SAE and metric charts I can't correlate dimensionally.

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#2
01-15-19, 02:33 PM
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Maybe it's a metric TR 12x3? Looks like its exactly 10 threads in 3cm...

#3
01-15-19, 02:54 PM
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Ahh, I only found metric being measured at 1mm. At 3mm it is spot-on 10 threads. Still haven't found how 12x3 correlates to 10 but all other dimensions fit into place.

#4
01-15-19, 03:01 PM
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I believe the TR12 will have a major dimension between 12mm and 11.7 mm... and you said it was 11.88, so...

at 3 *cm* it is 10 threads. that's exactly 3 mm per thread. That's where the 3 comes from. 3 mm.

30 mm = 3 cm... 30/3 = that's 10 threads.

Thus TR12x3.

#5
01-15-19, 03:18 PM
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Great info XSleeper.

Thanks for explaining the proper metric thread calculation. It opened my eyes to the goober I am. For some strange reason I was reading visual enumerations as mm, not cm. A total brain lapse and I can't use the before-my-morning-coffee excuse.

#6
01-15-19, 03:19 PM
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Thread pitch seems to be a bit in-the-wind and not ending on-the-tooth.
That's the threaded bar from a vise ?

I doubt you'll match that exactly.

#7
01-15-19, 03:51 PM
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That's the threaded bar from a vise ?

I doubt you'll match that exactly.
Yes. It is the TR screw from the cross vice. I knew I wasn't buying a precision lathe vice but was hoping this drill vice (\$50) would have been a little better than to offer 3/4 turn backlash. I intend to just place a sprung nut on each screw for pre-load.

As for matching thread, TR12x3 looks to fit the bill. Still, I do intend to use (or thread my own) plastic nuts which should offer a "little" wiggle room if needed.

#8
01-15-19, 04:09 PM
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I didn't mean to suggest it wasn't high quality.
Vice bars like that are not always tapped to a known size.

#9
01-15-19, 04:22 PM
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Location: Maryland, USA
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I didn't mean to suggest it wasn't high quality.
Vice bars like that are not always tapped to a known size.
Please don't think I was implying that, far be it. I was only shamefully and on the sly letting you know how skinflint I am.

I totally agree this class of vice (and possibly even better) may use either looser tolerances or altogether proprietary threading.

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