So Guys, correct me if I am wrong, but would it be right to say that the striations are being caused by the lack of resolution in the exported arc ?.

Tweakie.

That was my guess right from the beginning, but I thought you were saying that the striations did not match the Gcode...

Dan

Yes, I would have to say that's how it's coming through the GCode. Can you take the same file and actually machine it to see if it comes through with the same effect?

Side question for you, I'm seriously contemplating buying a laser engraver (been thinking about this for a long time actually), do your parts come though with the rounded egdes like that, or are you deburring them with a flame or buffing wheel?

Thanks,
Dave

Dave,

That's exactly the way the parts come off my machine - there is no refinishing or flame polishing. (I have had a lot of practice now and if you look back a few posts you will see that some of my earlier attempts with acrylic were rubbish).

In a way this is the reason for my question regarding these striations.
Many (perhaps all, for all I know) of the commercial laser machines are operated via a 'machine manufacturers Printer Driver' with acts as the post processor from the design software, typically 'Corel Draw'. Now there is some doubts about the way in which these printer drivers handle arcs and the maximum resolution they will allow to pass through because, it seems, that those I am in contact with who have a GCC laser are unable to produce a curved surface in acrylic without the striations. I have carried out a lot of research on this now and it is perhaps obvious from what I have made that a dedicated cutting software, such as Mach, way out performs these Printer Drivers - at least as far as cutting acrylic is concerned.
I know how to cut stuff with the striations and I know how to cut stuff without the striations - what I didn't know, until now, is what caused the striations.
You have all been most helpful here and as a result I think there is probably no solution for the GCC owners as long as they continue to use a printer driver and unfortunately their machines would not support Mach without some modification. There is one US business who is offering a Mach compatible addition but it is still doubtful if it will offer any improvement on the resolution of arcs issue.

Waffled on a bit but hope this is of interest.

Tweakie.

It may not be lack of resolution, rather lack of being a good circle. It could be both, but you wont know until you can get a proper circle. I tried to make one similar to the one you posted. Circle center is 0,0.  You can try it and see what happens if you like. If its still bad, I can bump up the resolution (and file length, of course) to test. Make sure you look at the code and make any changes you need before running.

Absolutely brilliant Sam.    just brilliant.

You have my full attention on this one - I have to know exactly how you did this - It is just about the best circle I have seen.

Don't suppose you could perform your magic on this foot or is that too much to ask ?.  

Tweakie.

You can use Gmax with CNC toolkit to achieve this.
http://www.cnc-toolkit.com/
All of it is free, but I'm sure Rab Gordon would enjoy a thanks.

Don't suppose you could perform your magic on this foot or is that too much to ask ?

I'll do ya one better. I'll make you one using arcs instead of the jagged lines.   You might have to scale it to fit your needs.

Sam,

I don't know what to say - you are just awesome.

Tweakie.

Ooops, forgot to say thank you.

Thank you Sam. Your help and support is much appreciated.

Tweakie.

No problem Tweakie. If we didn't enjoy helping out when we can, we wouldn't be here.
Out of curiosity, what software are you using that outputs everything in segments? Arcs sure do make for a cleaner file, cleaner cut, and a happier machine.

Hi Sam,

I think the foot was done with Adobe Illustrator.

I really wish I could do everything in arcs. I think I asked this question before but how do I do it in arcs please ?

Tweakie.