PDA

View Full Version : Lathe power feed - detent?



uute
10-19-2003, 03:04 AM
Hi Guys,

I have a question I've been wondering about for a while. When you engage the power feed on a lathe (cross or long.), shouldn't the lever have a detent to keep it engaged till you disengage it?

You guessed it, my tiwanese lathe hops out of gear if I don't hold the lever in. It does have a saftey cluth on the power feed rod, but no detent on the lever. Any slight chatter and she jumps right out. On smooth cuts, it just takes a little longer till all feed stops.

Just wondered if most lathes are this way? Never remember having this problem on a Clausing (25 yrs ago).

uute

Evan
10-19-2003, 03:55 AM
The feed for the lead screw may have a reverse tumbler. On my SB9 that must be tightened down with the square head bolt or it will "hop" out of gear. There is no way the half nuts for the carriage feed should disengage under load. On the cross feed you should lock the carriage to the ways and tighten the clutch, then engage the feed. It should not "hop" out of "gear".

BFHAMR
10-19-2003, 09:23 AM
Evan right. The lever shouldn't jump out of gear.

Is the lever you are talking about on the apron or on the headstock?

Dan

beckley23
10-19-2003, 09:25 AM
The feed should stay engaged until you disengage it. If it is like my Harrison there is a lever on the bottom of the apron that is lifted and catches a detent for feed engagement. Every now and then it gets crudded up and needs cleaning or oiling. You may have to take it apart to find out what is wrong.
Harry

wierdscience
10-19-2003, 12:36 PM
I once ran a little Taiwan 13x40 gearhead that would pull the same stunt,it had a cone friction clutch inside the apron that would get oil and swarf in it,once this happened it would slip and drop out,all it took was a few minutes with some disc brake cleaner and a blow gun to fix it.

It was one of only two problems the little machine had besides the tailstock constantly slipping.

uute
10-19-2003, 10:58 PM
Thanks guys,

that's what I thought, it should stay put. It is the lever on the apron I'm talking about(slide right - push down = crossfeed, slide left - lift up = long. feed).

Your replies inspired me to look at the parts diagram. It says there should be a ball & spring detent on the engagement. First glance - I don't see it in the hole, I'll have to look closer to be sure, or remove the casting to get an eyeball on it. Sure will be nice to rest my thumb!

If I get to it in any reasonable amout of time, I'll keep you posted.

Thanks again

uute