pancakeshake
Plastic
- Joined
- Aug 28, 2018
Hey All,
Im new to the forum, and new to running some DIY CNC equipment. I have run mills and lathes in my garage for years, and just kind of go by feel. Now that im programming parts, im seeing the importance of getting speeds and feeds right from the get go (not after you snap the end mill).
So here is the setup:
1/8" Annealed 4130 plate
1/4" 4 flute solid carbide
Z feed is ramped at 3°
F=9 IPM S=2300 RPM
Full depth of cut, Full endmill width
NO Coolant
I am simply getting the tool to full depth and just running a single pass around the profile of the part to cut it out.
My first 2 parts were about 19 linear inches each and I fed the tool at about 9 IPM & 2300 RPM. Cut like butter, no chatter, great finish.
The next 6 parts were about 9 linear inches of cutting. Tool started showing signs of getting tired (some chatter, heat discoloration). But it cut all 6.
The next 3 parts were the ones shown below. These are 7 linear inches around the part. The first one cut ok, the next one acted up and started what looked like melting the material. I dropped the feed rate, threw some cutting fluid at it and it started cutting ok to finish the part. The third part I ran extra slow and with cutting fluid just to finish the program. After that I changed end mills.
I went back to part #1 for my final part of the day and broke 3 end mills. It was the same program as #1 above, but about half way thru the part it started melting material again, and a lot of it. I was more curious than anything so I just let it keep going. As you can imagine, it broke. I had to knock out all the now hardened molten material before continuing. With a new end mill installed, I made it about 2" and bam, snapped off. I had to finish the part with a new endmill by feeding CRAZY slow.
Long story short, what the heck could cause something like this? Just too much heat (too much feed?)
What do other cut 4130 at? This was roughly 150 SFM, 4 flute carbide, no coolant, 1/8" DOC, full cutter width.
Im new to the forum, and new to running some DIY CNC equipment. I have run mills and lathes in my garage for years, and just kind of go by feel. Now that im programming parts, im seeing the importance of getting speeds and feeds right from the get go (not after you snap the end mill).
So here is the setup:
1/8" Annealed 4130 plate
1/4" 4 flute solid carbide
Z feed is ramped at 3°
F=9 IPM S=2300 RPM
Full depth of cut, Full endmill width
NO Coolant
I am simply getting the tool to full depth and just running a single pass around the profile of the part to cut it out.
My first 2 parts were about 19 linear inches each and I fed the tool at about 9 IPM & 2300 RPM. Cut like butter, no chatter, great finish.
The next 6 parts were about 9 linear inches of cutting. Tool started showing signs of getting tired (some chatter, heat discoloration). But it cut all 6.
The next 3 parts were the ones shown below. These are 7 linear inches around the part. The first one cut ok, the next one acted up and started what looked like melting the material. I dropped the feed rate, threw some cutting fluid at it and it started cutting ok to finish the part. The third part I ran extra slow and with cutting fluid just to finish the program. After that I changed end mills.
I went back to part #1 for my final part of the day and broke 3 end mills. It was the same program as #1 above, but about half way thru the part it started melting material again, and a lot of it. I was more curious than anything so I just let it keep going. As you can imagine, it broke. I had to knock out all the now hardened molten material before continuing. With a new end mill installed, I made it about 2" and bam, snapped off. I had to finish the part with a new endmill by feeding CRAZY slow.
Long story short, what the heck could cause something like this? Just too much heat (too much feed?)
What do other cut 4130 at? This was roughly 150 SFM, 4 flute carbide, no coolant, 1/8" DOC, full cutter width.