metalmadness
Hot Rolled
- Joined
- Nov 25, 2015
Hey all,
Let me preface this by saying that I am not a rookie. Ive been machining for 10 years and run a shop.
I'm having trouble breaking taps!
Last week I broke a 1/2-13 tap in some O2 Tool steel on the last hole, last peck! Well I blame that on the tool steel and nothing else.
Howver, Ive been breaking far more taps than usual lately, specifically in aluminum. Currently on a new Hurco VM10i machine, running about 800-1200 RPM for aluminum. First question, is that way too fast for general usage? I ask because I have successfully tapped many 1/4-20 holes running 2000rpm in the past. Sometimes I peck tap, sometimes not, depending on the hole. I leave plenty of clearance below the tap point if it is a blind hole.
Ive been running mostly spiral flute taps for chip clearance. Kennametal taps (kinda shitty), as well as Widia and some Emuge. Well in the past I have used OSG taps for steel alot and those things are amazing. Should I consider changing back to OSG taps? Some of my taps are uncoated, some are TiN or ZrN coated. Should I stick to uncoated?
Anyone have a rigid tapping recipe that just works? And what brands of taps are best for aluminum? Cost of the taps is not an issue but I would prefer not to have to get into carbide.
Also, I form tap for my smaller holes. Should I just suck it up and get forming taps across all sizes?
THANKS!
-cm
Let me preface this by saying that I am not a rookie. Ive been machining for 10 years and run a shop.
I'm having trouble breaking taps!
Last week I broke a 1/2-13 tap in some O2 Tool steel on the last hole, last peck! Well I blame that on the tool steel and nothing else.
Howver, Ive been breaking far more taps than usual lately, specifically in aluminum. Currently on a new Hurco VM10i machine, running about 800-1200 RPM for aluminum. First question, is that way too fast for general usage? I ask because I have successfully tapped many 1/4-20 holes running 2000rpm in the past. Sometimes I peck tap, sometimes not, depending on the hole. I leave plenty of clearance below the tap point if it is a blind hole.
Ive been running mostly spiral flute taps for chip clearance. Kennametal taps (kinda shitty), as well as Widia and some Emuge. Well in the past I have used OSG taps for steel alot and those things are amazing. Should I consider changing back to OSG taps? Some of my taps are uncoated, some are TiN or ZrN coated. Should I stick to uncoated?
Anyone have a rigid tapping recipe that just works? And what brands of taps are best for aluminum? Cost of the taps is not an issue but I would prefer not to have to get into carbide.
Also, I form tap for my smaller holes. Should I just suck it up and get forming taps across all sizes?
THANKS!
-cm