Econemy Thread Wire's

stupoty

Active User
Registered
Joined
Dec 2, 2012
Messages
1,717
Hello,

I used my thread wires today and remembered that the chart that comes with them has a few typo's on in.

Their an awesome china brand, being fair the rubber clips to hold them on a micrometer are quite good. :)

Always worth a check if you have a cheep cheep set of wires.

Stuart
 
There are many here who have never used thread wires.
Sounds like you've used yours several times.
Please consider giving us a how to primer on when, why, and how.
I wonder if the presumed complexity scares prospective new users.

Daryl
MN
 
I have a set of thread wires and I know how to use them. It is not really too difficult to do as long as you have five arms or know the simple tricks that go with them that are not in the instructions. So far I have been able to avoid actually using them in anger. When I really have to, I will.
 
The trick is a wine cork to poke the wires into - and the bottle to drink :)

They're not really that complex to use, they come in a set with a chart which tells you which wire size for each thread pitch, and simple sums to get from the micrometer measurement across the wires to the thread pitch diameter. They're the reasonably priced way to measure threads accurately, so you can make them accurately!

Dave H. (the other one)
 

The holders that come with them make it quite easy to use them, all though iv'e seen them stuck into blue tack or corks which also looks quite good.

I was making a couple of bolts for a stuffing box on a hydraulic Cylinder which is installed. I don't have a nut of the correct size to check the bolts with and testing it the piston wasn't really an option.

My usual method is trial fit a nut , cough cough :)

I looked up the spec for 5/16 NC in machineries handbook, it has diameter info of; major dia, pitch dia, and minor dia.

The pitch diameter is used for measuring with wires, so i look up the tpi on the thread wire chart (a correct one :) )

My chart lists it as this,

Mesurement over wires - constant from table = pitch diameter

The pitch diameter for the 18tpi 5/16 is 0.2764
The constant for 18tpi is 0.04789

Pitch diameter + constant = target mesurement
0.2764 + 0.04789 = 0.32429 (I rounded down to 0.324 as my target)

Their a bit of a faff to use but both bolts came out to size (yay)


Stuart

Just noticed they are mesuring as 322 ish so maybe a couple of thou under Or my mic technique when taking photos.
 
Last edited:
The trick is a wine cork to poke the wires into - and the bottle to drink :)

They're not really that complex to use, they come in a set with a chart which tells you which wire size for each thread pitch, and simple sums to get from the micrometer measurement across the wires to the thread pitch diameter. They're the reasonably priced way to measure threads accurately, so you can make them accurately!

Dave H. (the other one)

The price point is one of the main reasons I got them, their dead handy and quite cheep, a set of thread mics would be quicker but I don't think I would use them enough to justify the spend.

hears a link to a data sheet that appears to be correct :)

http://www.icscuttingtools.com/pdfs/Thread-Chart.pdf

Stuart
 
I used the 3 wire method for this thread before chucking and parting off the waste. I was surprised how simple it was to do following Machinery's Handbook (which I typically struggle with). It begins on page 1990 in the 29th edition and continues for few pages. BTW, after parting and crowning the brake fit perfectly. I'd do it the same way again (3 wire) except I would skip the relief groove and just back the cutter out of the thread at the right time.
MuzzleThread.jpg
Dave
 
I clearly recall being intimidated by all the numbers and terms.
This topic can be a little frightening.
For the thread/gear Noob here is a link to terminology: http://www.threadcheck.com/the-three-wire-method-of-measuring-pitch-diameter/technicalinfo/
I'm not pretending that this link is the best, or only.
Nor have I got this thread and gear thing figured out. However, I've made alot of progress by reading and re-reading content on the topic.
And, in turn making some gears and threads.
I've not yet used wires/pins to measure spur gears. But, I believe it should be the same process.
I'm very slowly tooling up to cut a bevel gear (yep, one of about 3dozen projects). Any tricks or tips?
Or am I following the wrong rabbit trail again?

Perhaps I should start a new thread (pun:). However, I believe it fits the theme of the OP.

Daryl
MN
 
I clearly recall being intimidated by all the numbers and terms.
This topic can be a little frightening.
For the thread/gear Noob here is a link to terminology: http://www.threadcheck.com/the-three-wire-method-of-measuring-pitch-diameter/technicalinfo/
I'm not pretending that this link is the best, or only.
Nor have I got this thread and gear thing figured out. However, I've made alot of progress by reading and re-reading content on the topic.
And, in turn making some gears and threads.
I've not yet used wires/pins to measure spur gears. But, I believe it should be the same process.
I'm very slowly tooling up to cut a bevel gear (yep, one of about 3dozen projects). Any tricks or tips?
Or am I following the wrong rabbit trail again?

Perhaps I should start a new thread (pun:). However, I believe it fits the theme of the OP.

Daryl
MN

I haven't used them for measuring gears but good point I guess it would be similar.

Making bevel gears that sounds difficult but very rewarding :) I would use the method of making about 10 practice ones first , ha ha :)

Stuart
 
I would use Pee-Dee brand. Tom Griffin says they're the best.
Maybe Brown&Sharpe.
 
Back
Top