I realize there are factors that affect this but just in general. can you cut alot with them of after a few cuts are the dull . thanks
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It varies but unless you are doing something crazy, a very long time.
If you start seeing burning excessive tearing, its time to swap your bits. But even a cheapo $11 chinese carbide bit will last a long time. Its obviously very hard to qualify that (what material is cut, how deep, how fast, how long and under what conditions, what speed) but if you are a new user i bet you will break that bit before you wear it out.
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thanks; yes i am new to cnc, just know what i have been reading while researching. my main purpose for the machine is to cut curvy strips 1-1.5’ thick from various hardwoods. i currently cut strips ,sand glue and bend in a form but can only do a few pieces at a time so it takes a long time to glue together the 80 or so pcs i need. by milling the strips already to shape its just a matter of little sanding , stack them and glue all at once. therefore eliminating the bending. But if i will go through a bunch of bits to do one board it won’t be cost effective. I know it will take time to learn speeds and feeds doc etc. would getting 80 or so strips out of a bit be unrealistic ? thanks
Hi
From my experience it varies a lot.
Most of my work is profile cutting kiln dried British Oak in a variety of thicknesses from 5mm up to 25mm along with milling out troughs.
I have tried a many makes of bits SPE & Amana are the 2 I have settled on with Amana being the slightly better of the two
My usual speeds and feeds for a 1/4 / 6.35mm bit are
Cutter is cutting fully width
Step Down 2.5mm to 4mm depending on material thickness
Feed 70 inches per min
Plunge 30 inches per min
RPM 19,500
Apologies for the mix of units but that’s how I roll
No doubt some will question some of the figures thw 19,500 rpm being the main one but after 18 months of testing this is what works for me.
Its not unusual to get over 1,200 linear meters of profiling from one bit.
I clean the bit regularly using router bit cleaner and a brass wire brush and have at times just touched up the edge with a fine diamond card
Burning and tear out are the usual indicators that something is wrong but dont always assume its a dull bit
Hope This Helps
D
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yes thank you i’m just trying to figure all this out
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@CSM Hey Darren, I’ve settled on those two brands as well and I agree that the Amana is better (maybe even more than “slightly better”). However, from a cost perspective it’s pretty much a no-brainer:
1/4" Downcut End Mill:
SPE = $16
Amana = $29 Uncoated (and $38 Spektra coated)
That’s almost double. I save the Amana for real important cuts and the rest of the time just use an SPE. If the Amana lasted twice as long it’d be the way to go but that hasn’t been my experience either.
@bkwoood Butch, that’s a good use case for avoiding the bending process. I think you’d be able to get 80 or so pieces easily if you got your speeds/feeds right so that it’s taking some nice chips and not dulling prematurely. Also, (like Darren), I’ve sharpened them a little as well from time to time; especially for end mills that I’m just using for clearing and then do the fine work with newer bits. And Darren’s numbers are very close to what I’ve found works well with hardwoods. Hardwoods are not easy on end mills.
WARNING FOR NEWBIES: Never use anything bigger than a 1/4" end mill with the little underpowered Makita; the router will break or even literally start on fire. (Do some searching here.). And by using it in a CNC you immediately void its warranty as it’s not an acceptable use in Makita’s eyes. So those beautiful surfacing bits you see? Forget about them.
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A long time or 1x forgetting to set z
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thank you jim, that’s very helpful inffo. did not know about the warranty. seems there’s only two routers to use the makita and carbide by shapeko. do the coated ones really make a difference. thanks again
lo I’m I’ll probably do that at least once
I’ve only broken 1 when my daughter walked up and hit estop. On a wall mount the z carriage drops to the left and it ran though bolt in the fence.
I started with amana coated but wish I should have started less expensive and as things wore out replace with coated. I’m not sure I’ll ever need to replace any. Only carve every other week or so
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