How fast for my lathe spindle?

[John Hill]

IMGP9196 by aardvark_akubra, on Flickr


I have a Drummond 3 1/2" flat bed lathe from about 1908. It has bronze bearings with oil cup lubrication. My next task is to rig up a motor for this and I would like indications on the maximum speed I should allow for in my drive system. Spindle is about 1" diameter.

Thanks

 

[lazylathe]

Not sure about spindle speed?
About 860 to maybe max 1000 rpm?

Love the lathe!!!
Did you restore it?

Andrew

 

[moconnor]

Hello John,

What a beautiful lathe. Did you restore it?

Andrew is spot on for spindle speed recommendation. I just looked on lathes.com.uk and found a Drummond speed plate from a similar vintage lathe and the maximum RPM was 875. In 1908, the predominate tool material was high carbon tool steel, so the cutting speeds that were possible were 1/3 to 1/2 of high speed steel (HSS). The lathe's spindle is a plain bearing design, so 1000 RPM would be a safe bet for a maximum.

If you haven't seen the Drummond pages on lathes.com.uk, you definitely have to check them out. There is a wealth of information there. http://www.lathes.co.uk/drummond/page3.html

There are photos of Drummond countershafts there and you are sure to get some ideas for your design.

Regards,
Mike

 

[moconnor]

Hello again,

Looking at your chip tray and the relief near the headstock, it looks like your lathe may have originally been a foot-powered version. Do you still have any of that equipment? I know that it isn't practical to use now, but it sure would be cool. Thm:

Regards,
Mike

 

[John Hill]

Thanks Andrew, Mike.

Yes, I have seen the lathes.uk site, in fact I have practically memorised the pages relating to my lathe! Seems I should have studied the 'M' type pages too which give an indication of speed for that model.

Yes, it was originally treadle and I have the iron legs but the treadle itself and the flywheel were lost long ago.

 

[xo18thfa]

Gorgeous lathe!! Thm: Thm:

Wonder if you could find a period motor for the set. Something like and old Bodine.

 

[steamer]

I would set it at 860 then. The spindle will generate heat as the square of the journal velocity...if you double the speed, you get 4 times the heat. It don't take much. Once the gap closes up, the temp will take off and it becomes a chain reaction...sometimes resulting in a seizure.

I would start slow and walk the speed up easy and keep checking the housing for temp. If its hot enough to hurt you , it's hot enough to hurt it......If she's happy at a 1000, and it turns good parts...Your there!

Just don't want to see anything happen to that pretty lathe...that's all. :bow: :bow: ;D

Dave