Machine went crazy

Post Reply
maineshops
Vectric Apprentice
Posts: 219
Joined: Sat Feb 23, 2013 11:47 pm
Model of CNC Machine: home built

Machine went crazy

Post by maineshops »

I cut a pattern from design and make yesterday and it cut perfectly..today I cut the same pattern and half way through it plunged down in Z about .100 and ran off the pattern in y about an inch. Any ideas what might cause this phenomenon. As it was doing this the stepper made a growling noise off and on. Coulden’t tell which one. Shut it down . Raised the head up and cut air for a bit and coulden’t get a repeat. Any ideas? Stumped in northern Maine Dan

SteveNelson46
Vectric Wizard
Posts: 693
Joined: Wed Jan 04, 2012 2:43 pm
Model of CNC Machine: Camaster Stinger using WinCNC
Location: Tucson, Az.

Re: Machine went crazy

Post by SteveNelson46 »

Probably static electricity. Usually associated with the dust collector but not always. Power down everything including the computer (not just restart) and try again.
Steve

User avatar
Rcnewcomb
Vectric Wizard
Posts: 3802
Joined: Fri Nov 04, 2005 5:54 am
Model of CNC Machine: GCnC/WinCNC
Location: San Jose, California, USA
Contact:

Re: Machine went crazy

Post by Rcnewcomb »

Might be static from your dust collector. Check your ground.
- Randall Newcomb
10 fingers in, 10 fingers out
another good day in the shop

User avatar
Xxray
Vectric Wizard
Posts: 2107
Joined: Thu Feb 17, 2011 8:47 am
Model of CNC Machine: CAMaster Stinger 1
Location: MI USA

Re: Machine went crazy

Post by Xxray »

Could be any number of things, if its not repeating then go right back at it. I know its helpful and preferable to identify a cause but thats not always possible.
Doug

User avatar
scottp55
Vectric Wizard
Posts: 3574
Joined: Thu May 09, 2013 11:30 am
Model of CNC Machine: ShopbotDesktop 5.5"Z/spindle/VCP10
Location: Kennebunkport, Maine, US

Re: Machine went crazy

Post by scottp55 »

Dan,
Kinda sounds a bit (made a growling noise) that you may have topped out your Z, and lost position?
Know you just upgraded to VCP10....Maybe check your Z1 and Z2 settings haven't changed? Also check your "Home" Z position?
If you opened someone else's .CRV and saved it.....VCP uses last settings...maybe it changed then?
scott
Attachments
SMALL OLDMANOWL FOR B.jpg
"One accurate measurement is worth a thousand expert opinions"

GMH


scott

maineshops
Vectric Apprentice
Posts: 219
Joined: Sat Feb 23, 2013 11:47 pm
Model of CNC Machine: home built

Re: Machine went crazy

Post by maineshops »

Thanks much for the input. I’ll. Check each point and correct any possible issue a d proceed. Dan

maineshops
Vectric Apprentice
Posts: 219
Joined: Sat Feb 23, 2013 11:47 pm
Model of CNC Machine: home built

Re: Machine went crazy

Post by maineshops »

I ran this pattern with ventricle machinist are there any special things I need to do to run the pattern in vcarve

User avatar
Leo
Vectric Wizard
Posts: 3030
Joined: Sat Jul 14, 2007 3:02 am
Model of CNC Machine: 1300 x 1300 x 254 Chinese Made
Location: East Freetown, Ma.
Contact:

Re: Machine went crazy

Post by Leo »

The growling noise sounds to me like lost steps. Sound like gears grinding?

My vote is that your Z axis topped out OR there was some sort of obstruction. On my old machine just moving UP then down was enough inertia to cause lost steps --- then it would do EXACTLY what you describe.
Imagine the Possibilities of a Creative mind

www.leosworkshop.com

maineshops
Vectric Apprentice
Posts: 219
Joined: Sat Feb 23, 2013 11:47 pm
Model of CNC Machine: home built

Re: Machine went crazy

Post by maineshops »

Leo thanks much , I’m having trouble understanding how the problem came up on the second run after it ran the first one ran ok. I am not very literate on this subject so you have to spoon feed me a tad.i don’t mind digging for information if I know what to dig for. Dan

ezurick

Re: Machine went crazy

Post by ezurick »

maineshops wrote:Leo thanks much , I’m having trouble understanding how the problem came up on the second run after it ran the first one ran ok. I am not very literate on this subject so you have to spoon feed me a tad.i don’t mind digging for information if I know what to dig for. Dan
Unfortunately I don't think we can be much help unless we are standing at your machine. We can only make suggestions. However, from what you describe, I have to agree it sounded like a static electricity issue... when you have them, they are erratic and unpredictable. Several mentioned this, but you said nothing about it. Do you have a spindle boot for your vacuum? Is it grounded? Is you table grounded? Is you controller grounded? HOW are they grounded? After I discovered I was having static issues, which cause erratic behavior like you describe, I actually hooked up a thick (14 gauge) ground wire from my table bed, controller AND whirlwind vac to the outside ground metal stake. I have absolutely no static issues anymore.

maineshops
Vectric Apprentice
Posts: 219
Joined: Sat Feb 23, 2013 11:47 pm
Model of CNC Machine: home built

Re: Machine went crazy

Post by maineshops »

Cut the same pattern and it went just fine. I appreciate each thought on my issues and thanks Dan

Savannahdan
Vectric Wizard
Posts: 394
Joined: Sun May 03, 2015 12:25 pm
Model of CNC Machine: Axiom AR8
Location: Savannah, GA

Re: Machine went crazy

Post by Savannahdan »

Sounds like a problem that I had that turned out to be solved by better grounding for static on my machine. I wasn't sure what to do but I ran the wire from the dust boot through the dc hose to the grounding screw on my dc unit. A couple of days ago I pulled an old Wood Magazine Best-Ever Workshops 2001 issue and found an excellent article on page 92 covering dust collection grounding.

SteveNelson46
Vectric Wizard
Posts: 693
Joined: Wed Jan 04, 2012 2:43 pm
Model of CNC Machine: Camaster Stinger using WinCNC
Location: Tucson, Az.

Re: Machine went crazy

Post by SteveNelson46 »

Gary Campbell posted an excellent video on you tube showing his recommendations on grounding.

Steve

SCG
Posts: 8
Joined: Thu Jul 26, 2018 8:02 am
Model of CNC Machine: Axiom AR8 Pro

Re: Machine went crazy

Post by SCG »

2 cents on topic

My machine "has gone crazy" twice and I was able to identify the issue.

1st scenario was when I made changes to the dust collection hose. I use light duty dryer hose since it's cheap, conductive and won't put strain on the dust boot. I fed this hosing through the cooling hoses and spindle mount on gantry so it was unobtrusive. What happened is the conductive dust collection hose was touching the spindle when setting Z zero using the puck. Earth ground of dust collector was interfering with Z zero touch off puck connection. This caused my Z axis to jog up and down within a 1-2 inch Z travel. Readjusted hose and no more issues

2nd crazy spell: I ran a 3 hour program late night and decided to run the last tool path early next morning. I started the fluting tool path, watched first couple paths and walked inside to get coffee. Murphy's Law occured when leaving machine unattended for a few minutes. Z axis went nuts, plunged straight down to Z zero with a .5 D 2" long end mill. Then continued on X axis cutting straight through my material and the spoil board. Very bad. It was 19 degrees in my Virginia shop that morning which caused problems with the rich auto A11 HHC. The extreme cold affected the HHC when reading G code from the USB flash drive. So, those are 2 proven causes of a machine losing origin and G code. Hope this helps.

Post Reply