It’s not really possible to ground a good insulator like PVC (or acrylic etc. etc.) as they don’t conduct.
There are various anti static sprays and coatings that can be applied to give insulating materials a thin coating which is sufficiently conductive to drain away the static charge. This is unlikely to work on the workpiece being cut however.
It’s also worth noting, unless it’s lightning, in which case you need rather different precautions. Static electricity has very little current and only needs a tiny leakage to ground to bleed away the charge. You don’t need thick wires or low impedance connections to ground, most anti-static items are only partially conductive and it’s common for them to have a high-resistance connection to ground for safety reasons.
Those who’ve had success wrapping a non-conductive hose in bare copper wire have provided a discharge path for charge buildup on the outside of the hose to ground, before the hose can accumulate sufficient charge to zap the frame or stepper wiring. The hose is not grounded, but the static is being discharged before it can upset the machine.
I think you will have to discharge the static at the source or as close as possible, the router. You can run a copper wire from the router to the frame of the machine or to a ground at a plug in the shop. You have to discharge the build up of static or it will find a path to ground and discharge on its own. That path is through the controller and/or usb connections. PVC is a static generator when cut. I cut PVC pipe on my chop saw and it has pvc dust stuck all over it.
@MarkDGaal since you’ve taken the lead on this static testing, understand a couple of things.
Static is developed when something moves.
There are only three things moving on our Shapeokos:
Air from the dust collection system
XYZ parts
Router/spindle rotor
Vacuum and dust collection “grounding” methods have been discussed ad nauseam and have proved their effectiveness.
The XYZ parts are easily “grounded”, because we already have wires routed to them and indeed they may already be “grounded.” (There is that pesky isolated power supply, though. )
That spinning router rotor is another problem altogether. The manufacturer has spent many hours developing the perfect electrical isolation for their product, because they want it to pass all the regulations that allow it to be a hand held item under many difficult scenarios. All parts accessible to us are obviously spinning and thus create an issue with wear-and-tear contact!
Anything we do to reduce/eliminate our problem with static will have to also reduce the isolation built into the router parts because our routers are designed to be hand held.
I’ve been considering a solution to the rotating shaft isolation, but am hesitant to reveal it publicly (beyond my control, lawyers, etc.)
Folks have shown how to defeat the double-isolation of the trim routers using a 3-prong cord — for liability and safety reasons this should not be done.
Grounding from the body of the router via a strip of foil tape on the dust shoe which then connects to a conductive hose attached to a vacuum which is designed to ground said hose is the simplest solution and seems quite reliable.
Every time I look at this forum there are more disconnect and EMI issues. I never believed your data about how rare these issues are but you have to admit it’s getting harder to make those claims with a straight face. When are you guys going to address these problems properly?
A few weeks ago here in SoCal we had a pretty extreme easterly wind event with very low humidity, around 11% as I recall. I’ve always run a UPS connected to the controller and PC running the CNC software and never had a problem with disconnects. So just for fun, I unhooked the controller and PC from the UPS and plugged into the wall outlet, ran a test job and had a disconnect in just a few minutes. Reset, tried again and had the same result. So I changed everything back to the UPS and was able to successfully run multiple jobs. This is all anecdotal of course, but it did/does work for me.
I have been for months. If you want me to go away then fix my issues. I’d sure like one of these 2.4e boards that you spoke of instead of more bandaids.
Please write in to support@carbide3d.com detailing everything in a single e-mail, noting what has been tried and what hasn’t worked, include a link to this post and request that the ticket be escalated.
I’m happy to some test if anyone wants me to, just cover the cost of materials / mods. This as meant more as a challenge, but I can replicate the issue with very high reliability at the moment.
Aka it’s not a big deal if its in one particiular material i work with that isn’t really meant for surfacing operations anyway.
I actually used this exact material a month ago for a letter project. Cuts like butter! I didn’t do anything special with grounding or anything on my 2yo machine, and never had an issue (granted with a single flute)…so I’m quite puzzled as well. Must be an absolute TON of rubbing with that surfacing bit. I’m in central Ohio, so it’s a bit cold and dry here too.
I ran a few cuts without the vacuum, then decided I didn’t like snow everywhere inside. Even after adding my vacuum hose and cyclone in the mix to prevent flurries, I did not see issues.
Used this bit with my Makita router. Again no surfacing bit used though… My guess is that you’re best off sticking with a smaller diameter single-flute to do your surfacing albeit at a decent time cost (which you’ve probably already considered).
I’ve used a 2" (1/2" shank) surfacing cutter all summer without issue… and then: winter. Now? every time I use that same cutter, disconnect issues (That I’ve never experienced in 4yrs of using my SO3). My solution? throw an old stainless dog bowl full of snow on the shop woodstove, and let it re-moisturise the air. It ain’t always electrical - sometimes it’s environmental… depending on where you are…
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