[Woodworker100]

Seen lots of debates about which is the best bit for mdf.

I find 2 flute 6mm upper cut reliable, but leaves a fuzzy edge at the top edge. (And I hear Down cut does same to bottom edge).

Is a straight single flute a better option? Will it plunge as well?

I have made a small table and its a pain sanding the edges after cutting. Want to know for future projects.

[ger21]

Compression spiral.

[Woodworker100]

Compression spiral.

Does that get rid of waste quickly too?

[ger21]

Not sure what you mean? They are made for making full depth cuts in one pass.

[Woodworker100]

Not sure what you mean? They are made for making full depth cuts in one pass.

Oh ok. I don't think my spindle is powerful enough for one pass in 10mm. I'm doing 3mm passes with 2 fluted uppercut. I saw a vid on youtube where they compared bits and a straight flute seemed the best. I'm weary of its plunge rate though

https://www.youtube.com/watch?v=2FjXsZKrobQ

[ger21]

You shouldn't be plunging at all. Always try to ramp into the cut.

[Woodworker100]

You shouldn't be plunging at all. Always try to ramp into the cut.

Thanks for your answers ger21.

Does that apply to holes too? it only plunges to start the cut and a few holes here and there.

I'm cutting at approx 24,000rpm (Kress 1050) 3mm passes in mdf with 6mm twin flute spiral upcut atm. (top edges are very furry and require sanding).