rhoward
Hot Rolled
- Joined
- Apr 10, 2003
- Location
- Everett, WA, USA
Hi all,
I have a very nice 12X36" Craftsman lathe that I pretty well restored from the ground up. New spindle bearings, new belts, spiffy paint etc. I fitted it with an AXA style QC post and bought some very nice Kennametal carbide insert tooling designed for a Swiss CNC machine. I also fitted it with a 1hp DC motor and speed controller. It is beautiful!
Trouble is that I never use it because it chatters so badly. I have tried everything I can think of but even light cuts in soft steel produce a terrible finish. And yes I have done all the obvious things, nice and tight spindle bearings, tight gibs and tool on center etc. It chatters with carbide inserts, cemented carbide, and HSS bits equally well!
Two possibilities I have noticed may contribute to this problem.
1. The DC motor is pretty heavy and since it is cantilevered off the back of the machine it may contribute to flexing of the bed. I have tried several brands of V belts but there is always some vibration and bouncing going on.
2. I made a long taper attachment for the machine using Bishop Wisecarver V wheels and track. When I tested the attachment I was surprised to see that the chatter problem was greatly reduced. Hmm. Maybe my cross-feed nut and shaft are too loose? I have run several badly worn lathes before with terribly sloppy cross-feeds and not experienced such bad chatter as this though.
So what do you all think? I know this is a light machine but have heard that the Craftsman/Atlas should do better than this.
Randy
I have a very nice 12X36" Craftsman lathe that I pretty well restored from the ground up. New spindle bearings, new belts, spiffy paint etc. I fitted it with an AXA style QC post and bought some very nice Kennametal carbide insert tooling designed for a Swiss CNC machine. I also fitted it with a 1hp DC motor and speed controller. It is beautiful!
Trouble is that I never use it because it chatters so badly. I have tried everything I can think of but even light cuts in soft steel produce a terrible finish. And yes I have done all the obvious things, nice and tight spindle bearings, tight gibs and tool on center etc. It chatters with carbide inserts, cemented carbide, and HSS bits equally well!
Two possibilities I have noticed may contribute to this problem.
1. The DC motor is pretty heavy and since it is cantilevered off the back of the machine it may contribute to flexing of the bed. I have tried several brands of V belts but there is always some vibration and bouncing going on.
2. I made a long taper attachment for the machine using Bishop Wisecarver V wheels and track. When I tested the attachment I was surprised to see that the chatter problem was greatly reduced. Hmm. Maybe my cross-feed nut and shaft are too loose? I have run several badly worn lathes before with terribly sloppy cross-feeds and not experienced such bad chatter as this though.
So what do you all think? I know this is a light machine but have heard that the Craftsman/Atlas should do better than this.
Randy