Cutting tool chatter

[Marauder 1]

Hey all:
I've been trying to get re-acquaintaned with my lathe, I've gone through and did all the setup correctly (I think) but when I'm trying to do a facing or turning operation I seem to be getting a ton of tool chatter and it's leaving the cuts very rough. I've been trying to turn and cut some 1.25 inch aluminum. The part is less than 3X the diameter long. I haven't used a live center on the part because I don't want a hole on the end. It's going to become a cap.

I thought something might be loose on the cross slide so I went back last night and readjusted it again. Still no joy, I'm going to be going an getting some of those carbide insert type cutting tools today. I think part of the issue is those cheap Harbor Freight tools. I also think I might be not using the proper angles but I cannot seem to find any info on these HF cutters and the angles they need.

Any help here would be much appreciated.
Thanks
Mark

[jaysny87]

Sometimes it helps to turn your spindle speed down when performing finishing operations. Sometimes I will be roughing a part out at 1000 plus rpm and finishing at around 200 rpm in a similar size that your working with. It depends on the material type. Also it may help to play around with how much stock your removing on the finish cut. Sometimes taking to little material can promote chatter just as taking to much will. Also better cutters could help. Very rarely will I use cemented carbide cutters opposed to inserted (indexable) cutters. But even the cemented variety should be capable of leaving a good finish.

[Marauder 1]

Thanks for the info, yep, playing with the speed sure helped as well as some better tooling. I'm going to spend the money on a quick change system from Little Machine Shop. They have the A2Z system with a ton of goodies for about 175.00 That includes boring bars a new MT2 chuck carbide insert tools and more.

In the mean time here is a rough prototype of cap for some carbon fiber tubing. There is a recoil reduction system I'm designing going inside that tube when it's completed. The caps need to have some o rings installed to prevent the damping fluid from leaking.

cap.JPG

Stupid me scratched it when I dropped it. It looked pretty good before that.

Seeya
Mark

[Shepard]

Here's a set of index able lathe bits. Also if your cutting aluminum -- you need C2 carbide inserts. C6 inserts are for steel.


http://www.ebay.com/itm/3-8-INDEXABLE-C ... 4d1515aa0d