Simple Gearing for Metric Threads on Myford ML7 lathes with gearboxes

Unfortunately a number of errors crept in to the large and complex gear tables in the article. Brian has now checked each gear combination individually, and prepared a corrected PDF version, one table to a page, which can be downloaded from the article HERE. The individual pages can be printed off and laminated to give a handy workshop reference.

Details of the individual changes to the tables and some minor errors will be printed in MEW 215. Sincere thanks to Brian for putting in enormous effort to produce and check these very useful tables for anyone with a gearbox equipped ML7.

Neil

P.S. My apologies for the confusion I caused earlier, I had to create this thread before I could link the article to it. I have deleted the comments saying the link doesn't work as it should be OK now.

Edited By Neil Wyatt on 30/03/2014 18:34:21

I still have 4 sets of the 33 / 34 gears

As author I am happy to provide copies of the tables in pdf form, message me and include your email address for me to send them to you. Queries etc. can be handled the same way.

Regards

Brian

Edited By Brian Wood on 31/03/2014 08:30:33

Is this thread still active as it looks quite old. Reason is I have just purchased a Super 7B with qc gearbox on imperial. I would like to screw cut metric,just the basic sizes say 5mm to 8mm. I have downloaded the pdf sheets. But I am new to lathe type work so not sure which gears to look for & where they are on the machine. I know where all the gears are but just not knowing which ones it is that are changed.

You just need 34 & 33 Teeth Gears , then follow the chart for gearbox settings.These Gears fit onto the Tumbler or (Chart says Mandrel) the same thing, Hope this helps

Here You Go, available from Myford

Bill

Thanks guys. Quick response. Just need to work out where the tumbler gear is within the set. Looking at the myford pictures I have it refers to the tumbler gear which is a pair side by side just below the main transfer gear from the headstock. Made of tufnol. Surely not them as they are a pair for forward or reverse & both the same teeth. The gear below them is a pair of gears. Any help or a diagram would be great. I know it's new years eve & all. Happy new year to all. Regards Steve.

Below the tufnol pair, there is a cople of gears together on the dame spindle, held on by (I think) a screw.
The outer one of these is on a keyed stub. That's the driver gear.

Bill

Ah thanks I will have a look tomorrow.

HTH,

Rod

Edited By Roderick Jenkins on 01/01/2020 09:18:35

Cheers Rod, too late last night to go out and take a photo; Steven, just make sure you select the correct orientation for the larger drive gear, just out of shot in Rod's photo. That swaps between fine feed and screwcutting.

Bill

Thanks for all the input guys, i take it that you only change the one gear either 33 or 34 depending on the thread pitch & size. As in the picture you have put. Then adjust the gear train up to mesh correctly.

Steven,

And finally, select the appropriate gearbox setting to give the metric pitch you want to screwcut

Regards Brian

Sort of on topic or, at least, related.

I've restarted a part-completed Bengs models Sophie. Have now got to the need for 2mm thread production, Internal no problem but I don't have a 2 mm die and the usual go-to, (Tracy Tools), catalogue confuses me (easily done!) There appears to be 2 possibles (2mm x 4 and 2mm x 25) only one of which is in stock. I cannot find a similar reference on the 2 mm tap and don't understand the difference. Can anyone explain, please or point to a likely source?

TIA

regds

Bill

For M2, 0.4mm pitch is the standard for coarse thread, and is the default; ie probably the most commonly used pitch. 0.25 mm pitch is the standard for fine threads, so is a possible choice. Take your pick but I'd think that 0.4 mm was fine enough for most purposes.

Thank you, Clive - 0.4 it shall be , then ... if I can find one !

rgds

Bill

Hi Bill,

Try ModelFixings.co.uk. Their website currently shows M2x0.4 die, Ref MF-DM20 at £11.75.

Usual disclaimer. HTH

Maximiser - thank you for that info. I did confirm availability on their site, but, their 'certificate' gave my anti-virus (Avast) a hissy fit with dire warnings of doom! Went back to Tracy Tools and they now list what I want, so going that route.

Thank you for your help, nevertheless.

rgds

Bill