1/8" vs 1/4" end mills

(Tito) #1

From looking through the posts here, it looks like there’s not much to be gained from using 1/4" end mills instead of 1/8" end mills on the Nomad since the spindle power is such that gains in cutting size are lost in reduced feeds. I just wanted to make sure this was correct before going too far down the primrose path of dreams of faster milling with bigger end mills. So… not much use of 1/4" end mills on my Nomad, right? Thanks in advance.

(MachineHeadLabs) #2

In my experience, 1/4" 2 flute tools will speed things up on certain materials such as HDPE, which is self-lubricating and stays cool. If your CAM software supports it (I.E. Fusion360) it helps to use helical or ramping entries and reduced corner feeds in your tool paths. They reduces the impact on the spindle, which on the Nomad tends to stall.
Speed is kind of relative in my opinion. Noise is my bigger concern. Lately I’ve been using smaller stub length cutters and just letting the machine run fairly quietly and conservatively for longer stretches. However, if you are new, expect to break a lot of cutters in the beginning if going this route. 1/4" cutters are much more robust. Either way I would strongly suggest using coated cutters, especially if not using some kind of coolant or air.

(Luke) #3

1/4 will cut faster, deeper and with a good amount of precision. Great for clearing before detail is done.

(William Adams) #4

Agreed — since we’re in the Nomad area though, a reminder — 1/4" endmills are only suitable for softer materials in a Nomad.

(MachineHeadLabs) #5

I would add that 1/4" tools work best as a substitute for a face mill or fly cutter on the Nomad for squaring (plastic) stock, and would never attempt to cut a slot with one.

(Tito) #6

Thanks for your insights folks. Much appreciated.