GearTrain Troubles Chester Coventry Lathe

I have a Chester Coventry lathe and want to be able to turn imperial threads. looking at the manual I know that I need to change over the gear sets as per below:

'...as per below:" ? There isn't anything below.

What information are you looking for? Has your post been chopped short?

Brian

Thank you for replying. It was cut. I am trying to find out how to add in a copied photo. I have a metric Chester Coventry lathe. Like most lathes It has the facility to produce imperial threads by changing the gear wheels. Four in total. This is all shown in the manual. However it to cut imperial it only shows the size of the first 3 gears but not the 4th. It justs shows a line. I am trying to show a photo of the manual.

Mike

Mike,

Like most new members ... You would probably find it useful to read this: **LINK**

http://www.model-engineer.co.uk/forums/postings.asp?th=103028&p=1

MichaelG.

Mike, to add photos to a post follow the instructions in this thread

Edited By Graeme W on 27/09/2017 19:45:20

I hope the photo makes it clearer. Couldn't do it on PC but managed on an iPad!

Anyway calling Chester directly has not been very helpful so far. So I really need help on this as I have run out of ideas.

Mike

Mike, nothing was cut, whatever you thought you had attached was not there.

Also nothing showing up that you can see on your ipad

Have a read of the instructions the others have kindly linked to.

Ok havre read the posts on how to upload a photo. Thank you for the help on that. Photo should now be visible.

Mike

That's a cryptic chart!

I think it means that the 4th wheel for TPI values is usually 48t but that 46t or 52t are needed to produce the TPIs in the last two columns.

So, for example, on line AC, a fourth wheel of 48t gets you 14,16, 21, 22, 24, 36 and 40 tpi, while 46t gives 23tpi and 52t does 26tpi

Hope that makes sense. If not I'm baffled!

Dave

Dave thank you I think you are a very clever man indeed. Now that you have said it, it is now in plain sight! I couldn't see the wood for the trees. The line is a rather odd shaped arrow.

Once again thanks for that.

Mike

It does beg the question, what are the Module and D.P. Tables for?

Edited By Mike Nash 2 on 27/09/2017 23:26:16

The module and DP tables are for producing worms to mesh with either module or DP gears.

They are for cutting Module or DP worms.

Steve.

Beat me to it Keith.

Thank you Gentlemen, this evening I look forward to turning some 5/8 UNF threads! Cant believe I just wrote that.

Regards

Mike