- Joined
- Dec 22, 2015
- Messages
- 561
I've been milling some 1/4" wide slots in 1/4" thick mild steel and I'm trying to figure out the best method. These don't have to be exactly 1/4" wide since they are only for bolts so I have been using a 1/4" center cutting end mill and plunging the slotting. First try I plunged 1/3 depth then cut left to right, at the end of the slot I plunged another 1/3 depth, then reversed direction back to the start. Plunge final depth and then to right again. Second slot I plunged half the depthe and used the same process. Third time I plunged full depth and did it in one pass. I have now dulled 3 HSS end mills. I was running at 1000rpm and using some tap magic brushed on to the steel. According to my feed calculations using a 1/4" 4 flute HSS end mill at 1000rpm and a cut rate of 0.001" per tooth I should be travelling at about 5" / minute. I tried 1/2 that fee rate and found it to be way to fast. I had to slow to a crawl.
Am I doing something wrong? Is there a better way to do this?
I have ordered a 4 flute 1/4" carbide end mill for the next time and hope that will result in faster feeds and longer tool life.
EDIT; forgot to add the pic.
Am I doing something wrong? Is there a better way to do this?
I have ordered a 4 flute 1/4" carbide end mill for the next time and hope that will result in faster feeds and longer tool life.
EDIT; forgot to add the pic.
Last edited: