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Re: New CV features
« Reply #40 on: January 09, 2007, 02:18:38 PM »
I need to UP this post because everything Scott said goes doulble for me.  We have run test after test with Exact Stop On, Exact Stop Off, CV values all over the map, Look Ahead set low and high,...everything that Mach codes for.  The results are still inaccurate cuttiing.  We have the feed rate override (which really should just be called Override, as it also controls the Rapid move (which is not good  >:()) set at 100% or less all the time. 

Judging by the lack of response when Scott asked about inlays, I suspect that no-one using a CNC router with Mach has had enough accuracy to achieve this (which some would consider basic) application.  Anyone?

V-Bit carving and 3D also experience the rounding problem.  This is not just a 2D phenomenon. 

I feel bad for Scott, and I don't know if it was clear from his last post that the images posted were not made using Mach. 

Physics lessons aside, is there any light at the end of the tunnel here?, because we are running out of track!
« Last Edit: January 09, 2007, 02:46:37 PM by kree8tiv »
Re: New CV features
« Reply #41 on: January 09, 2007, 02:52:37 PM »
First off... I think the feed rate overide only affects the FEED rate not the rapid in the later versions of mach.

second, rounding is present in all machines, as Art stated, fanuc, mach and other machines capable of constant velocity. the thing is, most machines that do not have this problem use big enough servos to handle scary accelerations which make rounding a lot less. If you do not use constant velocity you SHOULD NOT see rounding.but maybe your machine is too flimsy that when it stops it wiggles a bit and and bad cuts are seen. if you set your acceleration way down, I mean WAY down, and use exact stop, im sure you wont see this, but then again, cutting times will go way up. so it is basically a trade off situation if your machine cant handle this shaking.

As for light at the end of the tunnel, well there´s QUANTUM, which is a whole new approach to things, which in my opinion is the way of the future, and I am sure there are not many controllers taking that approach.

Re: New CV features
« Reply #42 on: January 09, 2007, 07:06:58 PM »
To get the FRO to not change the rapid rate please check the box that Is in the pic. You need to know that if you are doing long moves the FRO is going to take longer to work...
What are you running for a table?? I have an idea that it is a table like a shopbot and you should try the test version of Quantum and tell me if it makes your machine run a bit better... you will need to put in a value of about 1000 in the Jerk amount under path smoothing. Also you will have to double you accelerations...

BTW I know who you are now and I can tell you that quantum will fix the problem as I used your old test file to check quantum :)

Hope that  helps
« Last Edit: January 09, 2007, 07:09:32 PM by Brian Barker »
Fixing problems one post at a time ;)

Re: New CV features
« Reply #43 on: January 26, 2007, 02:29:17 PM »
Thank you Brian,

Quantum is making a signifigant improvement, and I am pleased to finally learn what No FRO on QUE means! 

What kind of timeframe are we looking at to get a version of Quantum up with no limit to line numbers.  Testing 3d is a bit of a challenge otherwise. 
Re: New CV features
« Reply #44 on: January 26, 2007, 03:45:33 PM »
Use your Mach3 license and you should be able to run a program as large as you like ;)
Fixing problems one post at a time ;)

Re: New CV features
« Reply #45 on: January 26, 2007, 05:43:05 PM »

Thanks, the licence worked. 

2D files have improved dramatically.  Corner rounding is just about eliminated with Quantum.  Speeds, and acceleration is way more than twice as fast now. 

Funny thing though...

Now 3D files barely reach 5% of feed.  Any ideas?  With Path Smoothing, does it matter if you are in constant velocity or exact stop?  So far testing reveals no major differences. 

Offline Scott

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Re: New CV features
« Reply #46 on: January 27, 2007, 06:57:04 PM »
At the risk of dropping completely off the bottom of Art and Brian's Christmas list, I'll step back in here.   ;)

Kree, I just pretty much settled on a compromise of rounded corners and poor V-carves and hoped that the customer didn't have a problem with it.  I just did the best I could.  I got tired of spending a half hour test cutting to only have the same results most times.  The larger the V-carve design the better.  Smaller ones with sharp corners are worse.  So I'm sitting at the end of that track waiting.   ;)

Brian, I have found that Quantum is better with mainly longer linear moves and not a mix of shorter G01, G02, and G03's.  The type of files that I need to run act as if I have exact stop set.  I have run the gamut of the range of settings for "Max Jerk" with the only change being how fast the file runs.  I sent two files to Art a while back that exhibit this and I'll attach them here if anyone would care to try them.  Are these type of files (short straight and arc segments) to be considered the same as short 3D and V-carving types and therefore not optimized yet?

I'm able to almost double my acceleration settings, but because of the jerk setting not being applied to rapid moves, if I get too high it will loose steps on take off.   :o  Will this eventually be applied to rapids also?

« Last Edit: January 28, 2007, 12:07:25 AM by Scott »

Offline GaryB

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Re: New CV features
« Reply #47 on: January 28, 2007, 02:50:55 AM »
Hey Scott been testing your file, there's a couple of things I would like to try if you would send me your dxf for the 150 profile
I  don't seem to have the problems your having, just finished some 1" v-carve text and it ran as smooth as ever.
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Offline Scott

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Re: New CV features
« Reply #48 on: January 28, 2007, 12:35:48 PM »
Hey Gary,

Here's the dxf.  This file was made in Vector by selecting the outside ring of leaves (in consistent direction) and creating a 0.75" offset to the outside.  I then keep the outer profile and delete the stray inner parts of the profile.  At that point, it's already "Arc Fit".

I find that some v-carve stuff works ok in Quantum, but the next one will run hesitantly and slow or fast depending on the setting.

Thanks for looking.

I should add that this file runs fine in Mach3 (unless you add in too much CV Tol), but not in Quantum.  The gun runs fine in Mach3 (albeit with rounding), but won't run smoothly in Quantum.
« Last Edit: January 28, 2007, 12:42:14 PM by Scott »

Offline ART

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Re: New CV features
« Reply #49 on: January 28, 2007, 10:32:02 PM »
Hi Guys:

   Just a note as I run by...

    Many will ask why Quantum slows down some 3d files to very slow.. Heres the reason..

 In trapezoidal accel, there is a finite time that acceleration takes to get to speed, with Jerk correction,
this time is increased. Though you can tune for faster accel, the accel as a % of total time of move is increased
by up to 200% or more. This doesnt affect longer moves. However, very small line segment 3d files will
never get to get up to speed before having to decelerate. All move, not matter how small must accel, then decel.
Quantum will attempt line concatenationnext to speed up those moves..

  Glad to har its working well for many of you, we worked very very very very hard :) on its implementation,
but remember, its alpha code...