Very help full! I had relegated these blasted pins to the seldom used & infuriating tools cabinet but you have inspired me to try & subjugate them once more.
Thanks for the video! If the threads are small enough, the 2 pins can be separated by a few threads, they don't have to be right next to each other. Easy to feel the squarness then ;)
I'll have to give that method a try next time I need to measure threads. I broke down a while back and bought a set of those flexbar holders. Nice camera work too.
Nice, I alway put a flag of painters tape (masking tape that doesn't leave sticky behind after you remove it!) on them and that why when you do fumble them they are really easy to find and it keeps the 2 wires together. Also on bigger threads I use a little bit of grease to glue the wires in place a bit so they don't fall as easy.
The New wire Sets are a pain in the butt . A old Tool Maker I use to work with gave me a old set of wires that work great. The old sets are 2 pieces with one wire bent in a U shape and another single wire. The U shaped wire is used as 2 of the wires and it's much easier to control than 3 separate wires. I remember asking the old Tool Maker what he thought of CNC. His reply was "CNC takes all the fun out of it" LOL.
I remember the first shop I worked in there was a woman that ran a Hardinge turret lathe. She had these sets of things that looked like coil springs with ends wound like a torsion spring. She would use them to measure the pitch diameter of the threads. The spring was wound slightly smaller than the thread so when you wound it on it set down into the thread. Than you measured the OD of the spring. The only thing is you needed one for each size of thread. I have never seen these since then. This was about 40 years ago. The reason I would not like to use a bent wire or these devices to hold the wires is. It is important to be able to feel the drag on the two wires. The drag should be the same on the two wires or you don't have the mic perpendicular to the thread. With a bent wire it would not be possible to tell this. So I prefer to use three separate wires.
Yes for large ID threads I use Gage Maker with their software. But you need a sets of spheres for depending on the threads pitch and type of thread. You can also measure OD threads with their system with the proper OD tool. Its a very good system but costly.
I put the 2 wires against the thread and wrap a piece of masking tape around the end leaving a little slack between the wires as to not pull the wires together leave a tail on the tape to make it easy to find if you do drop them and do the same with the single wire. I have to go out to a production machine sometimes to measure a thread and it makes it much easier to find the wires if you drop them.
thank you. I enjoy your videos very much and have subscribed to them. you make amazing parts! I want to ask - suppose I don't have a thread wire kit - if I take 3 identical pins that will overhang the top of the threads i guess there is some trigonometry to be made so it can be measured? taking into account the pitch, angle and actual measurement with the micrometer?
Thanks for showing us this method I will give using wires a go, I have only ever used parallels before but the difference in price between wires and parallels is massive ($40.00 for wires and about $600 for parallels) . When using parallels there is a standard (1/4" for UN and 6mm for metric) that you need to subtract from your measurement to get the effective diameter of your thread. Do wires have a simular standard that you need to subtract? Also who makes the standard that you were measuring? I have seen a number of people online from the U.S using them. Thanks Peter
As a fellow user of Marlco parallels, if you have a digital micrometer you can measure the parallels together and then reset zero, that way you get an instant reading of PD when measuring the thread, but I expect you already knew that. Do you find the little bits of plastic that holds them rather lacking in "usability"? I have a couple of designs for better usage, another tuit I must add to the "must do a video of it" list.
Thanks for the digital mic tip, I don't currently have a digital mic but will tuck that one away until I do, its a good idea. In your comment you spoke about 'PD' which I assume stands for 'Pitch Diameter'? I have always known this as the 'Effective Diameter', interesting how people in different places have different names for things. I agree with your sentiments on the holders, when they get a bit worn and then mix in a smear of coolant they quickly become a hassle to keep assembled while you measure, locking them onto the parallel would make them so much more usable. It's a shame that Marlco didn't put more thought into the holders because the parallels themselves are excellent.
I used the PD (pitch diameter) expression because it was the one used in the video to save confusion, but would normally have used ED. The terms are interchangeable, Machinerys Handbook lists both so it is not necessarily a different place/name thing. A sliver of paper tightens the fit but doing this on such an otherwise good, and expensive, bit of kit is a little disappointing. There is also a cunning variation on the PD wire method that uses a couple of turns of spring wire that fits over the thread and is measured in the usual way. Downside being you need one for each thread size. You can make you own using copper wire of the right diameter but you have to do the PD wire calculations. Even so it saves you dropping wire in the chip tray.
Have you heard of Marlco thread measuring parallels? Way easier than PD wires and ,sort of , direct reading of Pitch Diameter. Only downside, the cost!
Yes but I have never personally used a set. Also it seems that if the thread wasn't long enough and close to a shoulder they might give problems. As I said there are many ways to do this. This way has always worked for me on threads say about 2.00" diameter and less. Thanks.
Another of my favourite ways (which also overcomes your worries) is to wrap suitably sized soft wire around the thread, then you can't drop one of those pesky little ones in the chip tray. Trouble is you have to do the same calculation as PD wires, a PITA.
Thread Micrometer vs wires.. I recently move from 10yrs of being a cnc mill guy to the Mazak integrex. So my question being is I make alot of o.d threads now and hate using wires. Are the interchangeable anvil/thread mics accurate
In my experience three wire method is much more reliable and accurate way to measure the threads than a thread mic. If you want to ease up the hassle with three wires Mitutoyo makes these holders that have wires in them.
mikey_d amazon has a rubber set of holders for like 20$ . There color coated so you know what wire size to use . It’s semi stretchy so it holds onto the anvil.
The thread micrometer takes away the fussiness of handling three wires. We have a Mitutoyo mike with replaceable anvils that will cover a wide range of thread sizes. But the mike requires a delicate feel and the setup is expensive when the anvil set is taken into consideration. I think we were quoted over $300 just for an empty 2-3" frame that would use our existing anvil set. BTW an alternative to a three wire set is to use three number drills of the appropriate diameter. One last thing: The calculated "M" using the formula gives the top limit for a class three thread.
