feed speeds for ballnose bits
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feed speeds for ballnose bits
I just purchased a few 1/8" shank ballnose bits that are .032 and .064 dia. just out of curiosity before I use and break these. approx what feed speeds do you that have them use? I will be cutting in some hard woods such as Oak, Zebrano, Paduk, Purple heart etc...
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Re: feed speeds for ballnose bits
It’s not just the feed speed but also the depth of cutting that you should consider.
I would start real slow ( 50 IPM ) and move up as you feel more comfortable.
From what I have seen, in the finishing toolpath, the fist line of cutting is the hardest on the bit as it is cutting on both sides of the bit.
Maybe 20 IPM to start
After that I usually increase the speed.
Michael
I would start real slow ( 50 IPM ) and move up as you feel more comfortable.
From what I have seen, in the finishing toolpath, the fist line of cutting is the hardest on the bit as it is cutting on both sides of the bit.
Maybe 20 IPM to start
After that I usually increase the speed.
Michael
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Re: feed speeds for ballnose bits
Also depends on what stepover you are using. Once I'm done the first pass (which is cutting the full width of the bit), and if I'm using a 6-8% stepover, I often cut at 400ipm (18000rpm).
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Re: feed speeds for ballnose bits
Depends on a lot of stuff.
My machine is not capable of 400 IPM
DOC is an issue too. I generally go about 1/2 the tool diameter for DOC. Stepover is where you get the finish. On fine detail I like a 10% or less stepover. My machine can handle 75 IPM and even up to 100 IPM. Beyond that I loose steps on 3D stuff. I would start at around 40 IPM. Your machine may be able to go faster, but those are pretty small cutters.
My machine is not capable of 400 IPM
DOC is an issue too. I generally go about 1/2 the tool diameter for DOC. Stepover is where you get the finish. On fine detail I like a 10% or less stepover. My machine can handle 75 IPM and even up to 100 IPM. Beyond that I loose steps on 3D stuff. I would start at around 40 IPM. Your machine may be able to go faster, but those are pretty small cutters.
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Re: feed speeds for ballnose bits
Hi..
In this video (4:45) I used the same bit. But I just use only for 2.5D finish and no more than 2mm of wood like you can see in video.
About feed rate you must try starting with lowest speed you can and slowly increase.
Template: https://docs.google.com/open?id=0B-o2Pf ... GNMVUpNdXc
In this video (4:45) I used the same bit. But I just use only for 2.5D finish and no more than 2mm of wood like you can see in video.
About feed rate you must try starting with lowest speed you can and slowly increase.
Template: https://docs.google.com/open?id=0B-o2Pf ... GNMVUpNdXc
Alex Navarro
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Re: feed speeds for ballnose bits
Is the maximum feed speed determined by the load on the tool on the first pass when it has to cut 100% of its width .
If using a 10% step over for example ,the same bit would be able to go faster as it would only have 10% of load on the subsequent pass's.
Does aspire take this into account, when calculating tool path, or is it possible to set it ?
Thanks Harold
If using a 10% step over for example ,the same bit would be able to go faster as it would only have 10% of load on the subsequent pass's.
Does aspire take this into account, when calculating tool path, or is it possible to set it ?
Thanks Harold
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Re: feed speeds for ballnose bits
No and no.
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Re: feed speeds for ballnose bits
Thank you all for the fine feedback. will be my first use of a bit that small and just didn't want to snap it straight off even though I know they are stronger than they appear to be. Likewise, I don't want to turn a 20 min job into a 20 hour one either.
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Re: feed speeds for ballnose bits
In mach3 before you start the machine i normally set feed to 50%4240harold wrote:Is the maximum feed speed determined by the load on the tool on the first pass when it has to cut 100% of its width .
If using a 10% step over for example ,the same bit would be able to go faster as it would only have 10% of load on the subsequent pass's.
Does aspire take this into account, when calculating tool path, or is it possible to set it ?
Thanks Harold
Then after the first pass I can reset the feed speed to 100% and cut faster ( using the 2010 screen set )
Dan
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Re: feed speeds for ballnose bits
If you are using no roughing bit, try to start on one of the corners, instead of the middle this is a very short path to start with instead of a full length pass down the middle of the wood. Using a ball nose, I get the best result with a 6 or 7 percent step over, and eliminates sanding usually. The longer the small bit is the easier it is to break, a shorter bit will make more aggressive cuts.
If you have not used these particular bits before, you might make a roughing tool path with a large bit to start just to get used to them also.
Roy
If you have not used these particular bits before, you might make a roughing tool path with a large bit to start just to get used to them also.
Roy