Pm1030v lathe question on hi-lo speed ranges

[r-mm]

The manual for this machine seems to steer one to the low speed range and a sticker on the tach advises the low range for ‘cutting’. I am having a hard time seeing why I wouldn’t want the flexibility to go above 1000 rpm. If cutting refers to single point threading, this is something ive yet to do. Why not leave it on the high range - Am i missing something?

 

[KevinM]

Lower speed has more torque due to the pulley ratios.

 

[markba633csi]

I don't know if I'm a typical user but I tend to use speeds under 1000 rpm much of the time, and for thread cutting 60 or below
-M

 

[r-mm]

I have personally not yet cut threads but turn and drill a good number of parts all from 6061 aluminium so I'll experiment with the higher speeds. Easy enough to swap back/forth. Thanks.

 

[NavyShooter]

I've only used mine on low range, and have not felt hard done by in that. Higher speed might give faster materiel removal, but as mentioned, lower torque.

*shrug*

Let us know how it goes for you!
NS

 

[7milesup]

I hardly ever ran mine in low range unless working with steel, and even then I don't remember operating in low range. I too did mostly aluminum.

 

[T Bredehoft]

With an RPM/surface speed of 900 for 1/4" steel. low range is plenty for my work. I have used high for aluminum, but the whine of the gear train is annoyiing at the higher end. Yeah, I've moved the banjo to eliminate it, but....

 

[Larry$]

I'd stick to low range, at least until you have gained some practice. The motor will be happier if you keep it's speed higher, especially if it has a built in fan. The proper "cutting" speed is based on surface speed. Look those up in Machinery Handbook or what ever reference you use. As for cutting threads, go slow! Less than 100rpm. Look up Joe Pie's threading videos.

I'm not a machinist so the only time I go above 1000 rpm is to polish.

When things go wrong on a lathe, they happen so fast you can't react in time. Wear your safety glasses. Getting a curl of aluminum dug out of your eye,,,, not good!