Threading Dial Indicator for Metric AND Imperial Threads 

You did the math! Thank you! This is the content I yearned for and thanks to Stephan GTW for recommending you. Subscription button smashed and the like button smashed. Looking forward to more.

IMPORTANT SUPPLEMENT: In the example at 9:15 I messed up the numbers, sorry guys. The fraction 4.8 is for a thread pitch of 1.25mm, not 1.75mm.

That's the complete story how it works, thank you! I had to figure that by myself out with a pencil and Excel some month ago, because your video wasn't existing. ;-)

Hi, I have the EMCO Super 11 that I purchased in 1989 (imperial). I also bought the threading dial which I think they used on both metric an imperial. The dial is a little different then the dial in your catalog. My dial has three meshing gears on it, 14, 15, 16 teeth. I use the 16 but I don't use it much. I built a lathe stop foot brake pedal like the one in the original catalog so I stop my lathe at the end of the thread and reverse the spindle. On imperial lathes it is easy to know which threads don't require a thread indicator. If the thread is divisible by the lead screw then you can engage it anywhere. On the Super 11 the lead screw is 8 tpi, so 8,16,24,32,40, etc. work with no problems. I don't remember if the Super 13 came with a foot brake but this makes threading very easy. On critical threads where I want to stop at an exact place I use a hand wheel on the rear of the spindle.

they still teach that you have to have the clasp nut engaged at all times. I tried to explain it to some oldtimers in my company and they were stunned when it actually worked. Although I measured the leadscrew pitch to be safe and it was 5 instead of 6. I used your formula for the pitches you can disengage the clasp nut and all of them worked.

Absolutely brilliant explanation. I have the same machine. Where did you find the original documentation? If you'd ever consider scanning & sharing i would love to add that to my collection. Cheers!

Brilliant discription. Anwsered years of threading problems in a short video. Excellent

Wauw, this is really amezing. thank you very much for explaning it so nicely. I like to copy this for my AI Hembrug DR133. Can you give details of the gears you used? kind regards Harry

This is a great video, however the ending was rushed. I have a 1930's IXL Leader lathe with 6tpi lead screw. However this machine is flat belt driven so there is no reverse. I have to confess I got lost with the math at the end... if I understand it correctly if I am cutting 2mm pitch I have to wait for 40 revolutions? How does you dial indicate when the 40 revolutions has passed exactly? I would love to know how the old timers cut metric threads on these lathes with no reverse, no brake etc. I believe how they did it is to stop the lathe after the cut and use the tumbler reverse to reverse the lead screw, making sure to engage on the same number as the carriage is reversed.

I always like your work because it’s cleverly designed

Seems like I need to change out my 4tpi leadscrew to a Metric 6mm one then! Aw man :(

Thanks finally I understand what it’s all about. I will try to replicate the metric part but I have a small lathe 3mm lead screw so I think I need to calculate the number of teeth for the 2 small gears.

Great explanation of the problem. Need to make an electronic dial to do all the calcs with a display of a dial. Thanks for sharing, enjoyed.

This tool combine with an auto retract would really speed up thread cutting (See this link for a auto retract prototype ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-ZKOxnBFKKtk.html )

Most underrated machinig channel!

This screams for a small rotary encoder based solution. I love that you built a clockwork device, and I know there are computer controlled lead screws (the optimal solution) but for someone who wanted to "keep it real" having a small electronic unit to do all this conversion without having to go as far as you did would make some sense. I think I will build one for my mini-lathe before I go full conversion (which has seemed overkill.)

To simplify things why not two indicators - a metric and an imperial. One on either side of the saddle? Cheers

What is "opening the clath"? The part that engages the leadscde is called half nuts. Not a clutch.

Awesome video. Would love to see how you made the metric thread pitch indicator attachment.

Just Fantastic, well explained. Make me one. lol :)

With regard to Threading with a TDI, If you have time and desire, take a look here: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-Be8DHO4EaG8.html&ab_channel=Atelier-MD Is a Full-geared universal thread dial indicator In the description text of this video are all the information such as the entire technical drawing can be downloaded ALL FREE! Ich möchte mich ganz herzlich für dieses Video bedanken, habe ich mir die Inspiration für mein Gewindeuhr Projekt hier geholt! Beste Grüße aus Nordrhein Westfalen!

Super glad to see you making more content Alex! We all want to see it. Cheers from a toolmaker in Australia!

Excellent Video. Thanks and subbed. Thanks to SGTW for pointing out your channel.

Does “n” is for the number of teeth for the gear?

Excelent explanation, thank you

Great information for sure. But i think i will stay with my current way of Cutting Threads on a Manual Lathe. Metric Lathe with a Metric Lead Screw: disengage and re-engage for Metric drive back out for Imperial Threads.

Brilliant description and not in your native tongue, great kudos to you.👍

That's a great explanation of the threading dial. My metric Colchester Bantam didn't come with one, and your video inspired me to design one for my lathe. I'll only utilise the two metric dials. Thank you for making this video.

Bisch Du e Össi oder e Schwizer? ;)

I think you should do some videos on your V13! I just bought one to replace my V10p. My v13 looks identical to yours. I will be installing a VFD soon.

All of the metric threading kits for imperial lathes have a 127 tooth change gear in addition to many smaller gears and I never really knew why. This video clearly explains it, thank you!

I come here by a Stefan Gotteswinter indication and wow! So much technical information! Thank you!

Very nicly done. Good explanations and demonstrtions.

Thank you! I need to make threading indicator like this.

Just love your channel. Peace

I watched it again, I need to check if both of my lathes do metric and Imperial threads.

Nice job and well explained, in my personal case I think 90% of the threads I have to single-point are multiples of the leadscrew pitch so I can probably reverse the spindle for the rest of them. I have the brake and everything after all.

A couple of thoughts on avoiding changing indicator gears: First: gears of 20, 21 and 22 teeth will do everything you want. Cut all three gears on a gear blank sized for 21-teeth then the mesh centre distance does not change. Put all three on the same shaft. Then you can shift gears by sliding the shaft up and down. Second: gears of 35 and 36 teeth will do all apart from 5.5mm and 11mm pitches. Cut both on a blank sized for 35 1/2 teeth. Shift by sliding. Have a reversible graduated dial with seven divisions one side and five divisions the other side. The other graduated dial would have 12 and 9 divisions. Your method is very good but I would get confused over dots, double dots, squares and triangles.

Gratuliere! Tolle Konstruktion !! Servus aus NÖ!

I love the calculations for this. Just some additional finishing touches on the dials/gears and it'd be perfect.

Sub'ed thank Stefan

Thanks for the math! I only cut metric threads, changing the dial gear is not difficult on my Chinese lathe, but *remembering* to change it is!

Could you share the plans of your creation?

Alex- found your site from our friend Stefan. I enjoyed your video. Want to check out your other ones now. thanks

great explanation. I have a Boley 5LZ with a 6mm leadscrew and an internal gearing which makes the "pitch" 4mm per rotation of the spindle. Does this interfere wirh your formula's thanks: subscribed and liked. Hope you keep producing!

Great video..........'every day is a school day', as they say! Thank you for your time in putting it together!

Mate you've got an excellent channel. Mathematics is important to understanding. You have properly explained the relationship of the tool to the spindle when threading which is of great help to me.

I will never sell my Imperial tool room Okuma (yes 4TPI ledscrew) - but that didnt stop me from frecently buying a CNC lathe - one for show and the other for serious productivity improvement - I wont say which is which -:) Thanks again for an interesting and well presented video. Your spindle Bearing video was equally well appreciated - cheers Pete

This is engineering apply to machining at is best! Mixte this with the Colchester quick thread and you may just have something as nice than a Hardinge :)

Great video, thank You! Subscribed to Your chanel. I hava a weilier condor sort of similar to Your Emco. No indicator, may copy Your idea. Mine has a 2 speed motor and an electric brake that speeds up threading somewhat.

I am very happy that I found this channel! Thank you.

I have been thinking about making a thread indicator for metric threads and was discouraged when I found it would take changing gears on the indicator to make it work. Is your design somewhere so that I can download?

Interesting - seems like the right way to fix all this is with a resolver and a tiny computer board. A solenoid could time the engagement more perfectly protecting the nut and lead-screw..

Great work, and great video. Please do a full video on the build and machining of the dial. Id like to replicate it, with some slight improvements, for my 6mm lathe leadscrew. I have "screwed" up 3 threading jobs over the years because i forgot to change the thread dial gear. This would help greatly as im getting much older and foresee many more similar blunders in future. Subscribed. 🤙

Very helpful explanation. Thank you.

extremely nice work! very thorough explanation, also

Hello Alex, I just subscribed. Your explanation of how this works is perfect. I really appreciate the video. By the way, Stefan Gotteswinter showed a link in his recent video and I am glad he did.

You will be thanking Stephan a lot I'm guessing, subbed. But thank you for this in depth analysis of the threading dial problem. And it still is a problem! I'll be reviewing this vid a few times, perhaps a drawing of your gearing/dial mechanism would be popular. From Oz

Alex, I am really impressed by your comprehensive engineering approaches to the situations and phenomena you describe, and your very clear explanations. I also enjoy your attitude and sense of humor. I came to your channel because of the discussions of welding distortion. I am an electrical engineer learning TIG welding, and my electronics training is not much use for welding! I am welding a stainless steel project, and knew that the response of stainless steel to heat would be much larger than for mild/carbon steel, aluminum, etc. I watched your videos and did some experimenting, and now I have been able to quickly and easily reverse the distortion that my welds have caused.

Explained the process very well !

A closeup of the indicator during threading would have been nice to really understand the function, in the video we unfortunately can see nothing. Is any plan or schematic available including the required gears? That would it make a little bit easier to understand and maybe to adapt to an other leadscrew pitch.

Great video.I see your lathe has frosting marks on it. Did you scrape your lathe in , . I see your home country is the same as your lathe. I need to try make a gap for my Emco v13 as it is a poor design and I am suprised Emco would have done this. How do you stop your lathe so quick while thread cutting.? Have you got your lathe running on a vfd with a break resistor. Happy to have found your channel. Thank you.

So on my Emco V10p, which has a metric gearbox and 3mm pitch leadscrew, i can open the half nuts if i'm cutting 1mm, 1.5mm, or 3mm pitches?

I am new to your channel and just wanted to say that I found this very interesting.

Spectacular device

Lovely work and explanation!

"In the Metric World it's a little more complicated". But, but Metric is simpler 🙄 I still think a reversing lead screw would be easier. Not only to build but also to use

Exellent video

One reason metric is inferior to imperial.

any chance of video showing thread dial construction?

educational... thanks!

my lathe has a 5 TPI, I know, no joke. Do I have a metric or imperial lead screw?

Thanks for the analysis Alex. Metric guy here as well, had an apocalypse when I found out that I could break the 'half-nut engaged' rule for threads whose pitch fits integer number of times in the leadscrew pitch! :) (it is a bit risky though, since, without a dial, you may end up with mis-engaged nut: half closed nut that can drag your carriage but with a phase offset....Not nice if the thread is a difficult one o a valuable part...) (now I have ended up with an imperial lathe and though I can disengage nut when metric threading in order to stop at a shoulder I do have to reengage and reverse the spindle to go back...) Enjoying your work very much, thanks for sharing. BR, Thanos

you say 25 POINT 4 but you write a comma! ~~~~ very interesting video! Did not know metric lathe dont have threading dials often!

Instant sub. Looking forward to watching the rest of your videos. Keep up the good work and thanks for sharing!!!

Bud Spencer! 😝😂, nice!

THANK YOU SIR!