Easyscriber engrave attachment for Hypertherm torch's
 

Rounded Inner Corners

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TrinityFabworks
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Joined: Tue Apr 17, 2018 2:36 pm

Rounded Inner Corners

Post by TrinityFabworks » Wed Oct 31, 2018 8:22 am

I am having trouble with smaller shapes having very rounded off inner corners. I know that you can't avoid this to a certain extent because of the width of the cut, but it is more excessive than that. Sheetcam shows my actual cut path and, I am getting more of a radius than expected. I am using sheetcam and mach3. Would this be due to low acceleration values in mach or a certain setting in sheetcam? I can't imagine that it is with sheetcam, only due to the fact that it shows me the toolpath, and it doesn't look that rounded off in sheetcam.

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acourtjester
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Re: Rounded Inner Corners

Post by acourtjester » Wed Oct 31, 2018 10:32 am

yes speed has an effect on corners, also having a bigger kerf what size nozzle are you using.
It would help if you posted the thickness and what speed your using, and plasma unit.
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motoguy
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Re: Rounded Inner Corners

Post by motoguy » Wed Oct 31, 2018 11:03 am

Bulltear 6x12 w/ Proton Z axis & watertable
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TrinityFabworks
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Re: Rounded Inner Corners

Post by TrinityFabworks » Wed Oct 31, 2018 11:55 am

My kerf width is .031 inches. I am cutting 16 gauge on 30 amps with a spectrum 625 x-treme at 160 ipm, but right now my acceleration values are low. It is a ballscrew machine and it is on casters (making solid mount leveling feet for it right now). I've got the acceleration values so low because if it is higher, the machine shakes too much due to the casters. I will be able to bump up the acceleration (I believe) once I finish the leveling feet. I know its not ideal, and 160ipm is very slow for 16 gauge, but I get decent cut quality with my thc at the correct settings. I have my thc delay at 1 second so that eliminates it engaging on very small shapes. Are the CV settings in mach3 under the general configuration settings?

bigforkg
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Joined: Sat May 05, 2018 3:49 pm

Re: Rounded Inner Corners

Post by bigforkg » Sat Dec 08, 2018 5:18 pm

TrinityFabworks wrote:
Wed Oct 31, 2018 11:55 am
My kerf width is .031 inches. I am cutting 16 gauge on 30 amps with a spectrum 625 x-treme at 160 ipm, but right now my acceleration values are low. It is a ballscrew machine and it is on casters (making solid mount leveling feet for it right now). I've got the acceleration values so low because if it is higher, the machine shakes too much due to the casters. I will be able to bump up the acceleration (I believe) once I finish the leveling feet. I know its not ideal, and 160ipm is very slow for 16 gauge, but I get decent cut quality with my thc at the correct settings. I have my thc delay at 1 second so that eliminates it engaging on very small shapes. Are the CV settings in mach3 under the general configuration settings?
What are your acceleration and velocity set at? I ask because Im having the same and get vague answers.

robertspark
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Re: Rounded Inner Corners

Post by robertspark » Sat Dec 08, 2018 7:46 pm

It is physics

Search centripetal acceleration

Radius = velocity ^2 / acceleration
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