Sieg C6 Lathe new threading possibilities

Yeah, I know this is some times not helpful. Please take all of the suggestions that I have given you as untested and unknown to work. However, as I said the program does take into account the space available. I generated a full new chart for mine with my extended set of gears and sofar every one that I have tried fits perfectly.

Hi Graham,

any chance of combos for the following "gaps" in your list:

5.0mm, 5.5mm and 5, 6, 7, 9, 11.5, 12, 14, 19, and 27 tpi? With the original gear set supplied by Sieg.

Your computer program seems to generate more effective combos that actually fit. Is it commercially available?

Would love a copy. Regards Ian.

5.0mm - 40-90-40:75-30. Error 0%

5.5mm - Best I can get is 5.538mm which is 40-75-52:90-25. This is 0.6993% error

5 TPI - 40-80-42:80-30. 5.001TPI Error 0.0125%

6 TPI - 40-90-33:70-40. 5.987TPI Error 0.2147

7 TPI - 40-80-60:90-33. 6.985TPI Error 0.2147

9 TPI - 40-80-30:70-66. 8.981TPI Error 0.2147

11.5 TPI - 40-66:60-80-33. 11.525TPI Error 0.2191%

12 TPI - 40-66:70-80-40. 11.974TPI Error 0.2147%

14 TPI - 40-80-60:90-66. 13.970TPI Error 0.2147%

19 TPI - 40-66-80-60. 19.050TPI Error 0.2625%

27 TPI - 40-52:50-90:66-60. 27.016TPI Error 0.0606%

Hope this helps.

Edited By Graham Wharton on 31/01/2014 07:09:03

Ian,

If you PM me your email address, I will email you the full output from the program, which is gear combinations for all metric pitches from 0.01 to 5.5mm in 0.05mm increments and TPIs from 5 to 80 in 1/2TPI increments for the standard gear set. There are no limits on the errors in the output, so it will give you an output even though it gets no-where near the right number, but it does tell you how close it got, and what the error% is so you can make up your own mind if the combination is good enough or not.

Graham

Fabulous Graham.

What would I do without you?!!

Kindest regards. Ian

Hi All,

have finished checking fit and thread cut on all Graham's metric combos. They all work great. His computer program really makes a difference. Now I have every thread in common use today from 0.1mm up to 5.0mm.

When it's not over 40 degrees C. in my shed I'll start on the imperials! How I envy English weather!!!

Australia is getting so hot. It was 48 deg. C on Black Saturday. Where will it end I wonder?

Gentlemen,

My first post on this forum.

Please check out this link (**LINK**) on the Australian Metalwork Forum showing a simple modification to the C6 spindle idler setup that greatly increases the number of gear combinations that can be used, as it eliminates the clearance problem between the quadrant/banjo/first gear cluster and the standard 40T idler gear under the spindle. It also allows the first gear in the top cluster to be much smaller than the second gear in that cluster.

I will need to experiment with left hand thread setups to check if the modification can be used there also.

Andrew.

Hi All C6 guys,

well - I have just finished checking all 55 threads. They all work beautifully and get this chaps - they are all with the ORIGINAL set of 16 gears supplied by Sieg. No extras at all. No modification of the banjo necessary.

This has come about as a result of a collaborative effort from Graham, Andrew and myself. I only wish I saw this website 2 years ago. It would have saved me literally months of work.

I am preparing the final printed gear chart and will post it very soon. Range is mm, 0.1 and 0.2 for turning, up to 5mm for threading, and 5tpi up to 80 tpi, 55 in all.

I must thank Graham, Andrew and the forum developer/originator for making this all possible. When I purchased my C6 lathe, I was disappointed that it would not turn certain threads I needed, like 28tpi. If only I knew.

Now you guys are very smart indeed. Tell me why Sieg needs to produce a C6 with an imperial leadscrew which needs gears like 127 teeth to make metric threads, when the metric 2mm leadscrew can turn ANY thread? Do not use words like parochialism!!

Check out Sieg's website for their new C8 and C10 lathes. Posting chart soon.

Guys, please find attached ( I hope ) latest - last - final gear chart for turning and threading Sieg C6 lathe.

Tried to ensure no transcription errors. This chart contains the best of Sieg's original, Graham's and my own combos.

Gawd I've forgotten how to attach the chart. I'll play a little bit.

Thanx to everyone who helped.

I give up. How do I attach a chart?

Hi Ian,

if the chart is reproduced as a JPG you can save it in your album and show it in your post. If it is a program (or Excel file) you must save it somewhere on the web and link to it in your post. Hope this helps.

Thor

Thanx O' Hammer of Jupiter! Or was it God? Or Zeus maybe? Can't remember.

I'll give it a burl.

Something's wrong with the website - can't upload.

Ian's chart can be found here at this **LINK**

Andrew

Guys,

If you are interested in mods that will allow your C6 to cut most threads as accurately as it is possible with the supplied change gears, have a look at this link and give me your thoughts.

Regards,

Andrew

Gentlemen,

have almost finished gearing combos for all 17 BA threads, to be cut on C6 lathe. Does anyone want the chart posted?

It only uses the original gears supplied with the lathe.

Ian,

Please post it!

Andrew

Dear C6 Users; forgive absence. Have been working hard with our illustrious fellow forum guys. Have now produced, and proven, both by math and by usage, a total of 93 thread combinations possible with the C6 lathe. You will however need 4 new gears in order to produce fabulous accuracy. They are a 27, 32, 72 and 100 toothed wheels.

The latter 2 are available from SIEG. Unsure if they can or will produce a 27 or 32. You need to know a friendly, exquisitely capable machinist mate for the two small ones.

Hope to hear from you.

Ian, I hope I haven't found this thread too late to receive a response. I bought a metric version of the Warco wM240 recently, only to find that it has some gaps in the tpi thread range. The more glaring omissions to me are 18 and 24tpi, used in the Unified and Whitworth ranges. I've tried on-line change gear calculators but haven't found any solutions that make any sense. With the WM240 having the same 40T spindle and idler gears, I wondered if your calculations for the C6 would apply, if I obtained the suitable extra gear(s).

The table for the WM240 is below.

Alan

Edited By JasonB on 17/07/2015 18:45:37

Yes please!

Steve