I'm confused about what bit to use and what speed to use

I’ve got 1/4 in 45/60/90 degree v bits, I have a 1/4 in 2 flute up cut and down cut, and I’ve got a 1/4 in compression bit. All of which I got from maker made. I also have a set of 1/8 2 flute ball nose and flat nose end mills. What do I use if I want to make a pocket? Or just a straight line, do I just use the v bit for lettering? How do I know when to use what bit? And what about the speed for my router? I know it depends on the material also but where can I find this information so I can figure it out for myself? Thanks

V bits are typically only used for lettering or decorative egraving where you want a V shape groove.
up cut bits remove wood fast, but can cause splinters/roughness around edges. on the top side. but clean on the bottom.
down cut bits force the chips down so give you a cleaner top surface, but rough bottom if you cut through.
since the maslow is slow, always run the router at the slowest speed.

searching you tube for cnc bit tutorial will help you learn more, but a quick way is to just put them in teh router and do some manual cuts on scrap material. and Yes I do mean manual, as in your hands pushing the router around.

I respectfully disagree with MetalMaslow on one point. The better you know g-code the better you will be able to address issues. There for using the Maslow instead hand routing you’d get two lessons in one. What your bit does, and how g-code controls your machine and effects your cuts. Then again I tend to try to gain as much knowledge As possible from destructive testing.

so you are suggesting instead of using a manual test, to run a series of gcode settings like maybe cutting lines at various speeds and depths to get a feel for it?

In the end it sounds like you are both suggesting doing some additional testing outside of the desired cutting to become more familiar with the tool and setup, which sound like great ideas. More use = more experience = better products. I’ll add my voice to that. Keep trying and take notes and share what you learn. I found that my 1/8" bits cruise through mdf at 3-4 mm depth, at 500 mm/min, (4 passes for 1/2") but the same bit in plywood runs better at 750 mm/min and a depth of 2 or 3 mm for 5 or 6 passes. The 1/4" bits are way different. The sound of the router and its vibration correlated to the quality of the cut can help you hear what works.

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Exactly. You don’t learn by having things go right, you learn from your mistakes. More time = more experience = better overall experience.

Thanks for the replies. Sounds like what I am already doing. I’ve got a smaller maslow so its a little different for me but getting great results so far. Just unsure about this stuff so far. I’ll keep cutting and testing and taking notes and watching videos. I’ve been watching a lot of other cnc sign cutters and just watching how they cut signs and what bits they use, how they set up, etc. Again, thanks for the advice.

I’m kind of a newbie, so take it with a grain of salt. I’ve cut on plywood and particle board. Both seem to work about the same for me. I have used the 1/4" upcut bit that came with the kit, I usually take about 0.2" passes (so 4 on a 3/4" piece). I also set it to a total depth of 0.8" (as 0.75" doesn’t always make it fully through the material) and my tabs to 0.2". So, 4 passes and only installs tabs on the last pass. Saves a significant amount of cutting time, for me anyway.

On the 1/8" bit, I got a semi cheap one off of ebay…I forget what kind, probably down cut single flute? Anyway, I usually use it for making signs and stuff like in the “what did you cut today?” thread. Usually take a 0.125" pass. Usually 4 passes will go all the way through. Tabs take a bit longer at the 0.2" though, they don’t always work for just the last pass.

As for speed, that’s my noobness factor. I usually just set it to 40ipm…and the Maslow runs at whatever speed it wants to. Usually around 31 or so? Has worked fine for me thus far. But I’d imagine on harder stock, I’d have to slow it down.

I keep seeing some version of the following, “always run the router at the slowest rpm because the maslow is slow”
I want to know why. I have been running at 18k rpm since i started with the maslow. no issues with heating, smoking, fire etc. Most of the bits i use can run much faster than that. What am i missing?

you will burn up your motor brushes faster. create finer dust that clogs up your vacuum filter faster and dull your bits faster. There are no positives to running at a faster speed, when cutting plywood, maybe for other materials?

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I have now idea. But I will share what I don’t know…

  • The chip size is a good indicator if you compare it to the bit size and the counts of flutes, for heat transfer away from the bit and the worksheet. A good chip size transfers the heat away from the bit, fine dust does not, so the bit wears out, the bit gets hot and leaves burn-marks.
  • If you are after tool live for an expensive bit, you care. If you have disposable cheap bits from china, run them as you like. You might get cleaner cuts and change the bits constantly.
  • A router (just for me) seems an obsolete choice for the Maslow, because all are running too fast RPM for the feed-rate. I’ve changed from a 2000W Bosch GOF 2000 CE to a 500W spindle. It is a complete new would in speed-control, noise, choice of bits and waste material, using a 1/8 inch, ~ 3.175mm bit.

Once we can go beyond F800, with acceleration/deceleration planing, I might change to a 800W spindle, till then I am fine.
I have gained experience cutting cheap vs quality acrylic on my desktop-cnc. The right speed for the feed is the key that I have no Idea of.

Kind regards, Gero

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