Vacuum grounding

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Rando
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Re: Vacuum grounding

Post by Rando »

Sharkcutup:

The think to keep in mind about the static is that the charge build-up is between the spindle/bit and wherever the chip lands. The electrical + and - charges are separated by the cutting action. So, even if there's no connection to the controller, to get rid of the static you have to connect where the metal part of where those chips land, to the case of the spindle. That, and only that, will allow the charges to dissipate. If there's no "easy" path for it, then it will eventually go through whatever electrical bits are easier, or the air over time, or your finger ;-)

So regardless of your system setup, the zap-your-finger charge separation still happens between the same to items: the spindle and the bed.

You don't have to believe me; you can prove it to yourself by connecting a wire between the two and making a cut that would normally produce that static. The only thing it would disrupt is the touch-off plate action, so just connect that wire after you get your Z-height(s).

I never understand why people refuse to believe basic electrical principals that have been known since the time of the Greek and Roman empires. Honestly....

Regards,

Thom
=====================================================
ThomR.com Creative tools and photographic art
A proud member of the Pacific Northwest CNC Club (now on Facebook)

sharkcutup
Posts: 408
Joined: Tue Mar 08, 2016 5:23 pm

Re: Vacuum grounding

Post by sharkcutup »

Honestly - no friggin comment!
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Rando
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Re: Vacuum grounding

Post by Rando »

sharkcutup wrote:Honestly - no friggin comment!
With all due respect...you just did comment. Sharkcutup, are you even aware of the off-putting sequence you take with your responses? You ask, I reply, you challenge, I refute, you get irked. Just stop. Homey don't play that.

This thread on static control is not opinion.

Whenever someone gets zapped as they touch the machine, every inch of air that spark goes through is 76,000 volts (3 megavolts/meter, http://hypertextbook.com/facts/2000/AliceHong.shtml), and ones that strong HURT. More typically they are in the 20-30kV range and can jump up to about 3/8" (1cm). The dielectric strength of the wiring on your machine is less than 600 volts, and the ICs on that board are rated to no more than 1500V ESD (Electro-Static Discharge). It's a failure waiting to happen, and a significant design flaw that there aren't static drain wires bridging those hunks of plastic. The discharge path does not need to be a low-resistance ground wire, it just needs to bleed off the charge at the rate it accumulates, which is in the micro-Coulombs per cut chip.

If you want your controller to last, and you want to not get zapped every time you get near the machine, you'll put in a way for that static to dissipate.

Sincerely and respectfully,

Thom
=====================================================
ThomR.com Creative tools and photographic art
A proud member of the Pacific Northwest CNC Club (now on Facebook)

sharkcutup
Posts: 408
Joined: Tue Mar 08, 2016 5:23 pm

Re: Vacuum grounding

Post by sharkcutup »

Your most recent reply

"You ask, I reply, you challenge, I refute, you get irked.

Lets look back a moment shall we

My first post after your wire annoucement

"I do not believe your static-drain wire would be beneficial in my situation because I am using a water-cooled spindle with power inverter which is not plugged into the control box."

Excuse me but I do not see a question(???) in my COMMENT above!!!

You then replied and also asked a QUESTION within your reply

"Surely you're not interrupting the ground wire with your cutoff switch, are you?"

I replied with an answer to YOUR QUESTION I did not Challenge anything!!!

"No the Ground Wire is still present and functioning on the emergency cutoff switch!"

You then refute ASSUMING I have not or will not understand basic electrical principles and take measures to eliminate static in my CNC machine setup.

Then I briefly reply (I was not IRKED as you say I just don't have time for games!)

"Honestly - no friggin comment!

You then reply STILL ASSUMING I have not or will not understand basic electrical principles and take measures to eliminate static in my CNC machine setup.

"This thread on static control is not opinion."

Believe me Rando/Thom - I GET IT - static is serious and I HAVE taken steps to eliminate it in my CNC setup.

Respectfully,
Sharkcutup

Have a GREAT Day!!! :D

Be SAFE around those AWESOME machines!!! ;)
V-Carve Pro Tips, Gadget Tips & Videos
YouTube Channel - Sharkcutup CNC
V-Carve Pro 11.554

Rando
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Joined: Tue Jan 06, 2015 3:24 pm
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Re: Vacuum grounding

Post by Rando »

...and again...you add nothing to the conversation except a display of your own emotional irritation.
=====================================================
ThomR.com Creative tools and photographic art
A proud member of the Pacific Northwest CNC Club (now on Facebook)

Barry Anderson
Posts: 52
Joined: Sun Dec 21, 2014 9:55 pm

Re: Vacuum grounding

Post by Barry Anderson »

As stated in my original post, I could feel the static while using the shop vac to clean the spoil board. I did purchase the static drain wiring setup from Thom Randolph and put them on both of my machines. Since then, I have not felt any static when cleaning the spoil board. I am going to run a wire in the hose for the shop vac as shown on the Rockler site. If his wires will save my computers and controllers they will be well worth the money.

Barry Anderson
Barry Anderson
Anderson Custom Woodwork, Inc.

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