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How often do HSS end mills need sharpening? SOLVED
- Thread starter TomWS
- Start date
- Joined
- Nov 6, 2021
- Messages
- 60
Yeah, I get that.
What I am totally flummoxed about is that the link @mikey gave me had a SFPM value of 600 for aluminum and that makes no sense to me at all. It is inconsistent with every other source I've seen and I was looking for an explanation of that.
However, since this isn't contributing to the general wellbeing I'm going to accept all the help I've gotten and tune my cuts accordingly. Thanks all.
- Joined
- Dec 20, 2012
- Messages
- 9,422
Gotta remember that recommendations are for industrial/CNC machines that can run at those speeds; yours cannot so just go as fast as you can. For harder materials, cutting speeds will be much slower but for aluminum speeds are commonly faster than a hobby machine can achieve. Not a big deal. Just run it and feed by feel and you'll be fine.
You can also use power feed. Feed by feel to get an idea of a decent feed rate and dial in a rate that approximates it.
You can also use power feed. Feed by feel to get an idea of a decent feed rate and dial in a rate that approximates it.
The thing that I like about HSS is that a good shape is easy to keep sharp with a set of whetstones. Couple minutes and you're good to go again. I usually use them until I can see some imperfection in the cutting edge and then I sharpen.
We get used end mills from a local dealer, check for sharpness and usually can find suitable for hobby stuff.
Regarding speed, as already posted, material and machine matter as does coolant or lube.
We have some radio rack aluminum, gummy aluminum that sticks to the cutter.
Slow and somewhat heavier or fast and light, both work but need ATF for slippery to keep from sticking.
Steel, slow works best.
Slow rpm and slow movement as too fast of table overpowers the mill.
You get a feel for it with practice.
Sent from my SM-G781V using Tapatalk
Regarding speed, as already posted, material and machine matter as does coolant or lube.
We have some radio rack aluminum, gummy aluminum that sticks to the cutter.
Slow and somewhat heavier or fast and light, both work but need ATF for slippery to keep from sticking.
Steel, slow works best.
Slow rpm and slow movement as too fast of table overpowers the mill.
You get a feel for it with practice.
Sent from my SM-G781V using Tapatalk
- Joined
- Nov 6, 2021
- Messages
- 60
I finally got a decent 1/2" Roughing End Mill and it works much better than anything I've tried so far. It's a 3 flute from HTC Tool Company and seems to be good quality. We'll see over time.
I was able profile mill 0.7mm depth of cut, 10mm height, using my 9 IPM power feed without any issues. Spindle speed was 840 RPM and the mill was barely warm after each pass. I might have been able to cut deeper but I didn't want to push it.
Thanks again for the advice!