Feed and plunge rate

I am super new to CNC and curious what is a good starting point to find Feed and Plunge rate for an 1/8 two flute up cut bit going into MDF.

Google? :wink:

Man I have google’d youtube and they all said use a formula. I failed basic math so word problems are not my strongest suit.

Thank you sir.

you can find a free feeds & speeds spreadsheet on my site.

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Sorry for being flip in the first response. The problem with any pre-computed recommendations is they don’t take into account environmental factors and the type of cut. Your specific machine, the age of the bit, quality of the material, climb vs conventional, adaptive, etc. - they all matter. So in the end, everything is just a guide.

If you are looking for generalities, log into Easel and select a bit and material. It will give you super conservative feed rates and DOC. I always bump up the feed rate from what Easel recommends, but I have a lot of hours on my machine and I know what it can handle. I also know there are machines out there - the same exact machine as mine - that apparently can go faster with better cuts than mine. I don’t know why.

General rule of thumb - DOC = 1/2 the diameter of the cutter (0.0625 for your cutter); feed rate around 40-80ipm for wood and a 1/8" or 1/4" bit. I generally start at 60 and work out from there, but 40 is way more “safe”.

For a 1/16" or 1/32" bit, I cut the feed rate by 50% from above. DOC is still 50% bit size.

When things go south, I decrease the DOC before I change the feed rate. I’ve found DOC affects success more than feed rate – but that’s just my experience.

Hope that helps.

-Tom

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