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acorn board fusion 360 and smooth circle

Posted: Mon Nov 22, 2021 5:15 pm
by usinart
Hi
I want to make smooth hole in plastic and each time it kind of vibrating or shaking at the direction change . So at 3 o'clock and 9 there are somme kind of grouve or difference between the smootheness of the hole .
Q : On what variable I should play with for making it round and smooth .
thanks
Alain

Re: acorn board fusion 360 and smooth circle

Posted: Mon Nov 22, 2021 5:42 pm
by centroidsupport
Please always post a report when requesting support.

What motors and drives are you using? What is your depth of cut? What is your measured backlash?

Re: acorn board fusion 360 and smooth circle

Posted: Tue Nov 23, 2021 10:03 am
by CNCMaryland
So much in play here. The toolpath is important. This is something you need to do a ramped contour with.

Re: acorn board fusion 360 and smooth circle

Posted: Tue Nov 23, 2021 10:47 am
by rk9268vc
In fusion360 for each tool path you create there is a tolerance setting (I think it is either under the liking or depths tab)
This setting is the tolerance for how close it will follow the arc. (I think I have mine set at like 0.0002") This varies by type of cut, i.e. finishing passes are tighter tolerance then roughing, etc to save on file size and to allow smoothing.

You should also look under the linking tab for each toolpath to see how it is entering the cut, and if it is expected and if it is a smooth transition and is not ramping too aggressively for your machine. Remember to simulate every tool path and watch it :)

What I have had happen a few very rare times is if I have a lot of curves in rapid succession, the mill/acorn/pc seems to get bogged down and was kind of jerky in motion going around the curves. I have seen this happen in 8 bit 3D printers where it cant process all the movement commands as fast as called out and seems to get bogged down. Again, this is only in very rare cases and (so far) hasn't really been a problem

There are also smoothing settings in acorn, but I havent messed with them, and it seems to the uneducated (me) that they really shouldnt be messed with.


The other obvious thing that a lot of forum users will be quick to jump on is that your machine probably isnt ridged enough, strong/ powerful enough, or has too much backlash for the cut youre taking. So try it a lower DOC and feedrates

good luck!

Re: acorn board fusion 360 and smooth circle

Posted: Fri Nov 26, 2021 10:23 am
by martyscncgarage
usinart wrote: Mon Nov 22, 2021 5:15 pm Hi
I want to make smooth hole in plastic and each time it kind of vibrating or shaking at the direction change . So at 3 o'clock and 9 there are somme kind of grouve or difference between the smootheness of the hole .
Q : On what variable I should play with for making it round and smooth .
thanks
Alain
Use Intercon to create a Circular pocket as a test. Report back on how it goes.

Re: acorn board fusion 360 and smooth circle

Posted: Sat Dec 18, 2021 3:43 pm
by usinart
I would not pay for a conversional software that I would not use . If I make my hole with a spiral or a boring pattern instead would it be the same for the test .

Re: acorn board fusion 360 and smooth circle

Posted: Sat Dec 18, 2021 5:38 pm
by Sword
3 o'clock/9 o'clock is the place where that axis motor is reversing direction. I'd be checking for play and backlash first.

Re: acorn board fusion 360 and smooth circle

Posted: Sat Dec 18, 2021 6:06 pm
by ShawnM
Yup, I'd start with the machine first. Is it capable of making the cut you are asking it to do? What are your feeds and speeds and a pic of the machine would be great. Is it a rigid machine? Ballscrew or rack and pinion? Backlash? The material looks to be thick. I cut mostly plastic and aluminum on my router and I regularly cut 3/4" acetal with great precision but I don't ask more from my machine that it can handle.

Re: acorn board fusion 360 and smooth circle

Posted: Sun Dec 19, 2021 11:08 am
by usinart
https://photos.app.goo.gl/bTsU16J6G1sCd1Gm9
That is my machine .
The thing is after the post I find a post by Sword explaining a bit what is the smoothing setup , Then the light went on , that is the answer to my problem . All the trembling , shaking and bad word that go with it are finish. hip hip hourra !!!
It look like the answer to most of my problem .
As the text is in English and English is not my first language and also a bit technical also can someone help me with the what and what to do and also understand the process and thinking about that .
It would be a beautiful Christmas gift to me .
thanks and a good one to you :) :)

Re: acorn board fusion 360 and smooth circle

Posted: Sun Dec 19, 2021 12:54 pm
by ShawnM
We'd all love to help but first and foremost your PC DOES NOT meet the minimum requirements to run CNC12. I'd start with a new PC that will. Minimum specs can be found here: https://www.centroidcnc.com/cnc_pc_perf ... ments.html

Your CPU single thread benchmark is only 1411 and you need a MINIMUM of 1500 but shoot for a higher benchmark number for better performance.

With your PC smoothing will slow it down even more. You need more PC power first before we can address any other issues you might be having.

Also, your version of Windows has not been updated in 2 years. You need to keep windows current as well as your hardware drivers, especially the network drivers.

I'd start with these issues first and then look at fine tuning each axis for backlash.

When you cut those circles are you spiral ramping into the hole to the bottom?