Mill Bit ID and surface question

Evening All,

So a little question about this bit

Overall Length: 50mm/2"; Cutting Depth: 17mm/0.67"; Cutting Diameter: 25.4mm/1"
Shank Diameter: 6.35mm/1/4"; Weight: 49g
Product Name: Cleaning Bottom Bit; Material: Metal
Color: Gray; Shank Length: 29mm/1.14"

I am sorry if these are simple questions but I find sometimes I end up so confused and doubting myself.

Q1 - Am I correct in saying this has 2 flutes?
Q2 - Stepover I understand that decreasing the step-over distance will minimize the scallop height, but will require more steps, and take more time to surface my board. so I was thinking of doing my stepover at 50% of cutter diameter (is this a good starting point) or for surfacing is there a recommended setting / guide?

Thanks as always for the help and support you give.


yes, this is a 2 flute bit
While using a smaller stepover than your bit size is a good start, avoid using 50%. Hitting the centerline of your bit can cause burrs as the flat of the mill slaps against your material. You want the cutting edge to hit at an angle for your best finish. 35% usually works for getting a good surface on your wasteboard, as you’re making a very shallow cut so deflection isn’t much of an issue. Some people like to use higher or lower numbers than that, so it’s something you have to experiment with to hit your preferred sweet spot.

For that bit, the slower you can set your router, the better your finish will be, g-wizard say 3500rpm at 42ipm. However, most routers can’t go that slow. My settings for this (using the makita router) would be 0.35" stepover, spindle speed of 10krpm, feedrate of 118ipm, using climb milling. Your depth of cut would be anywhere from 0.01-0.1" without changing that feedrate, it won’t bother the bit at all, so it depends how much of your wasteboard you want to cut in to. Start with 0.01 and see where it goes… easier to make another pass than it is to try to put back MDF you’ve cut too deep into lol


Fantastic thank you very much for reply.

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