[Khalid]

Following is the simple technique u can dramatically increase the speed of ur 3D countouring... I use normally raster machining strategies as shown in attached figure.. I increased my Z-axis and X-axis motor accelerations twice as compare to Y-axis motor..

I got dramatic time reduction from 3 hrs to 45 minutes in one of the 3D carving..

U can see my work at following thread...
http://www.cnczone.com/forums/showth...404#post529404
Now What u comments on that???....:rainfro:

[miljnor]

So your saying that you increased your ACCEL in the X and Z axis (the two doing most of the work?) to save time?

Well if im reading this right, then you should've done that for all of em..because if the machine can handle the increased ACCEL while under load then it can handle it while not under load.

Or am I missing something?

[Khalid]

Basically the lengthy axis (Y-axis in my case) is the problem.... U may have various issues along Y-axis side i.e. Leadscrew Binding, heavy Gantry load, resonance... The lengthy axis is always prone to that issues, You can just optimize the cutting strategies to debottleneck this axis....this one axis can be debottleneck as per my above approach..

I experimented it myself and its really working for me..

Thanks

[miljnor]

Ah!

So in essence most of your cutting is in the smaller axis, to alleviate any issues with the longer axis.

I get it....thanks for the explanation.

[Khalid]

As Y-axis moving large weight (complete Gantry), its prone to large inertial forces too... All three axis acceleration well be different when u optimized ur motors..

Lets take an example...

My Z-axis can bear accelerations upto 50 @ 100IPM without loosing steps....
My X-axis can bear acceleration upto 45 @ 100IPM without loosing steps..
But My Y-axis can't go more 20 @ 100IPM..

So why not keep the acceleartion values say 43 for z and x axis and keep them 20 for y-axis... Now all u have to do to adopt raster startegies as shown in fig.

Does this makes since???

Regards
Khalid

[miljnor]

That makes your point perfectly clear and thanks for adding the new explanation....but you had me on post #3!

[steve323]

That makes sense for your machine that has a single motor for the Y axis. My machine has dual motors on Y, so it is actually the fastest.

Steve

[Khalid]

My Post#5 will still applicable to u... I don't know what IPM u are getting during complex 3D contouring???

[Khalid]

In my case, I use 180 Oz-in Sanyo Denki stepper motors..and they are best optimized with my home made controller cards...

If i use 425 oz-in motors, many using here at CNC zone, I will get great tremendous countourning... I can still get much more but increasing accelerations above certain limits cause excessive vibrations.. we have to see many many things..

[Khalid]

Somebody told me by installing Gecko drives u will get much smoother steppers and many other benefits..but yesterday i loose the competition..that was my only hope..

[Khalid]

Following is the post from one of our colleague who debottleneck his cnc as per my above mentioned procedure.

"I changed my machining to very similar configuration, x-raster so the machine 3D cuts in a x-z direction and y come into play only at the end of the cut. Also changed the look ahead in Mach to 100 lines.
My speeds went from 25 ipm to 100 ipm!! Its almost a little scary to watch after seeing 25 ipm for so long. A 3d carving in under an hour is a very nice change from 3-4 hours.
Maybe I can make some $.$$ in 3D carving.
Thanks for the tip!!

Mike
_________________
Mike E
"

This post is taken from Vectric Forum, where i posted the thread with the same name.Here is the thread:
http://www.vectric.com/forum/viewtopic.php?f=28&t=4220

[Khalid]

Nick also benefitted the above technique.. here is his views

Well I finally got a chance to try your method!!! It was definatly an improvement on speed. I had to set my acceleration up to about 100 on my X and Z axis in mach. I ended up losing steps on the second try. The first time I did the cut it took 1hour36min the second time I cut the same part I got it down to 1hour 11min. I still need to adjust the acceleration a little more for the 3d work. The DRO read from 24ipm up to 99ipm I would guess it averaged about 50ipm.

Thanks for the info Khalid it will help me cut faster!!!

Nick

[Khalid]

For all the guys who want to increase the carving speed..