Rough estimates of speeds and feeds on cheap bits?

#1

I’m still learning a lot, so I bought some cheap bits off Amazon to test with.
https://www.amazon.com/gp/product/B07178JW9J/ref=ppx_yo_dt_b_asin_title_o06_s00?ie=UTF8&psc=1

[Album] Imgur

Down in the “Customer Images” section it shows someone with a Shapeoko using them.

Does anyone have a ROUGH estimate for feeds and speeds on bits like this? I’m still learning how to calculate that, and I know it may need to be more conservative with cheap bits. I’m fine with experimenting to dial things in (and sacrifice a bit or two if necessary), but I’m not sure where to start since the quality might be questionable.

#2

(and there are closer pictures of the bits if you click on the pic in the post.)

#3

Just curious, are you milling circuit boards? That’s what these bits are for. The bits you buy will be determined by the material you are machining.

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#4

These are rotary burr bits, not a traditional spiral cutter. Speeds and Feeds will depend on what material you are cutting and what type of cuts you are making. If you are looking to engrave wood, these would prob do ok, at a shallow depth, but if you are trying to cut any sort of depth I think you are going to find these bits struggle. Regardless, I would recommend some test cuts ranging from 10 to 60 ipm at a lower RPM to see how they perform on the material you plan to use them on.

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#5

Cool. Sorry, I should have clarified. Just doing surface stuff in pine and poplar right now. Not planning on going deeper than 1/4 inch, and I’m fine if that (obviously) takes multiple passes.

The main idea I want to try with these is to do fine detail work around raised lettering… so hog out most of the stuff with a normal 1/4 or 1/8 bit, and then use the finer stuff here to go in and do smaller details in corners/intersections of letters.