Router Bit Suggestions

[Think713]

Like, how are you cutting these? Just trimming the edges down to exactly 4'x8', or a bunch of 1" circles?
I can't count the sheets of aluminum and acm I get out of one belin bit. Somewhere between 20 and 80 if I had to guess, but I don't have any way to gauge that honestly.

We usually are just cutting blank rectangle shapes. We are doing 24x36's often. And we bounce around from 3mil and 6mil thickness material. Sometimes we route on .5" PVC
Edit* We also do quite a bit of faces for pylon signs, so acrylic and polycarb... but we typically swap the bit for the acrylic and polycarb.

 

[JBurton]

18000rpm and about 100ipm

I run 20k rpm at 200ipm.

 

[Think713]

I run 20k rpm at 200ipm.

Is that for ACM or just your plastics as a whole?

 

[JBurton]

Is that for ACM or just your plastics as a whole?

Sorry, no, just ACM. Plastics like lexan, 3/16 thick, will get stepped through at 90 ipm, .125 first pass, with a .125 bit, 18700 rpm. Acrylics are usually for a push through sign, hogged out with a 1/4" bit, so it's between 60 and 90 ipm depending if it's a finished edge, 18700 rpm still.
Perhaps you are burning up your bits by running them too slow? Chipload directly correlates to heat removed from the system, too much heat and the bit will snap. I've never had problems cutting acm at 60ipm and 18700 rpm, I'll do it for more detailed copy cut out of a panel.
Do you have any ability to reduce the acceleration of the machine? I find most manufacturers prefer to push the motors to the max, and don't even include options for reducing the acceleration. Reducing my acceleration to 10% shows no real reduction in speed, instead of a 120" cut taking 2 minutes at 60ipm, it will take 2 minutes and 5 seconds. Too much acceleration puts lots of load on the bit all at once, causing deflection, potentially causing broke bits.

 

[Think713]

Sorry, no, just ACM. Plastics like lexan, 3/16 thick, will get stepped through at 90 ipm, .125 first pass, with a .125 bit, 18700 rpm. Acrylics are usually for a push through sign, hogged out with a 1/4" bit, so it's between 60 and 90 ipm depending if it's a finished edge, 18700 rpm still.
Perhaps you are burning up your bits by running them too slow? Chipload directly correlates to heat removed from the system, too much heat and the bit will snap. I've never had problems cutting acm at 60ipm and 18700 rpm, I'll do it for more detailed copy cut out of a panel.
Do you have any ability to reduce the acceleration of the machine? I find most manufacturers prefer to push the motors to the max, and don't even include options for reducing the acceleration. Reducing my acceleration to 10% shows no real reduction in speed, instead of a 120" cut taking 2 minutes at 60ipm, it will take 2 minutes and 5 seconds. Too much acceleration puts lots of load on the bit all at once, causing deflection, potentially causing broke bits.

Our bits arent snapping, theyre chipping.

 

[Think713]

Sorry, no, just ACM. Plastics like lexan, 3/16 thick, will get stepped through at 90 ipm, .125 first pass, with a .125 bit, 18700 rpm. Acrylics are usually for a push through sign, hogged out with a 1/4" bit, so it's between 60 and 90 ipm depending if it's a finished edge, 18700 rpm still.
Perhaps you are burning up your bits by running them too slow? Chipload directly correlates to heat removed from the system, too much heat and the bit will snap. I've never had problems cutting acm at 60ipm and 18700 rpm, I'll do it for more detailed copy cut out of a panel.
Do you have any ability to reduce the acceleration of the machine? I find most manufacturers prefer to push the motors to the max, and don't even include options for reducing the acceleration. Reducing my acceleration to 10% shows no real reduction in speed, instead of a 120" cut taking 2 minutes at 60ipm, it will take 2 minutes and 5 seconds. Too much acceleration puts lots of load on the bit all at once, causing deflection, potentially causing broke bits.

And yes we have full control over the speeds and feed rate... Its all inside the colex software.. but the settings are default for the material that is input into the system. We dont do any pushthru stuff... Mostly just faces for signage, nothing too indepth. And our acrylic and plastics default at 24000 rpm and 70ipm
I think its just cheaper bits and we need to try something a bit better.

 

[JBurton]

speeds and feed rate...

Speed is your spindle rotation, feed is your top speed, but acceleration is how quickly you go from standing still to full tilt.
And then yeah, as you say they are chipping, I think you're right pointing to cheap bits. That aluminum skin on acm should not compete with the bit in terms of hardness.

 

[Think713]

Speed is your spindle rotation, feed is your top speed, but acceleration is how quickly you go from standing still to full tilt.
And then yeah, as you say they are chipping, I think you're right pointing to cheap bits. That aluminum skin on acm should not compete with the bit in terms of hardness.

i woulnt say it competes... what ends up happening is the top layer starts to fray and then i have to shave off all the edges which is annoying and time consuming.