For what it’s worth, I’ve had my SO3 for about 5 years and never felt I was in an emergency stop situation. Don’t get me wrong, I’ve destroyed plenty of stock, broken bits, and had all kinds of interesting things happen that weren’t supposed to. I’ve never had anything like the router mount falling off or the X acids falling on the table.
When do you guys use your e-stop?
I think the feedhold is really valuable though.
For the record, I agree that it should be made easy to cut all power in an emergency… I’ve just never had an emergency.
Steve, first if you don’t feel comfortable, maybe you should refer this to a friend who is Knowledgeable with electricity.
Having said that you could just open up that surge protector strip (make sure it’s unplugged), snip the black wire add a section of wire to it and connect those two wires to the emergency switch. (Leave the rocker switch alone…)
As Liam stated, and forgot to add…small machines, like the Shapeoko + Router only draw about 8 - 9 amps MAX and this small E-Stop (10 amp) switch will work just fine.
I have this very same setup for 4 PLUS years, and have hit that switch many MANY times. Relax Liam…really. Sigh. Let’s not add complications that are truly not necessary.
Yep, there seem to be lots of switches available on Amazon US.
A Powertek which you’d have to wire up, and others which are pre-wired to just plug into.
My caution on just wiring in an E-Stop button is that not all of those are rated to switch 9 Amps inductive load at 220V so it’s worth making sure you’re getting a switch that won’t just fizzle out.
Anything rated for a power tool should be fine, table saws etc. all use more power than a Shapeoko & Router as Rich says.
And again, like Rich says, if you’re not comfortable with doing electrical stuff, get a plug in unit or find somebody who is, don’t want to hurt yourself trying to be safe.
Yep,
Like you I’ve chewed up a few clamps, set the zero in the wrong place etc. and those all just wasted wood.
The only one which scared me was a 1/2" shank cutter coming loose and wandering down the collet because I hadn’t tightened down hard enough on the 12-13mm collet. I was very keen to hit stop before that made it any further…
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I’ve had that big paddle-type kill switch on my table saw, bandsaw and table router for years. I’ve had to hit it a few times during my 40 years of furniture and cabinet making. I even have an emergency call button that I could crawl to to page someone & a voice activated 911 call system when I work alone. Accidents do happen, and this cnc machine (I’m a newbie) is no different. Always better to be prepared for the unexpected. Thank you all for the guidance.
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I did something similar in this post. I like it killing router power and using the feedhold so it doesn’t ruin my gcode or project. As long as travel stops and router is not running I can’t see a reason to power off the grbl board.
Not sure how to link it properly.
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Yup - most consumer grade woodworking machines up to 1.5HP in the US come with simple power switches like this.
Unlike 115V power, there’s lots of different types of connectors for 230V, so you probably won’t find anything prewired for them. But, they all should switch both “hot” 115V lines like this one.
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You were correct. I gave this a shot…the unit cut off as soon as the router turned on.
I considered getting a DJ switch panel, but decided on the Rube Goldberg approach. I’ve now installed a paddle without a magnetic switch that works perfectly well. The paddle controls / kills the power to a triple gang that holds switched sockets for the Shapeoko, the router, and the laser. A separate triple gang is fed directly (no shut off) and has switched sockets for a light, the computer, and vacuums. It’s working well enough.
I don’t understand what you said here. Could you please explain?
I hooked up my router, Shapeoko, and Laser plugs in a gang after the magnetic switch. I turned on the switch, checked all the sockets, and everything was powered and wired correctly. Then I powered up the router and the magnet switch turned off immediately. In fact, a GFCI on that circuit triggered as well. Not believing in coincidence, I did it again with the same results. So, to further debug, I turned the shapeoko on alone then off, turned the laser on alone then off, then turned the router on and it happened again. As my Final test, I unplugged the three gang from the magnetic switch, and powered it directly from the wall (taking the switch out of the equation), then turned on the router…all was fine. SO my conclusion was that the switch could not handle the draw from the router.
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Thanks - now I think I understand, but am a bit surprised that the relay contacts in the switch didn’t just weld together. The motors in most routers have huge current draws on startup, which is probably why some are rated for lower power motors than their current ratings would suggest. I’ve started and stopped the “2.25 HP” Bosch router in my router tables for years with one of those simple (non-magnetic) “Router Switches”. The shop does the same with both of their router tables - one of which has a “3 HP” router.
The GCFI tripped both times…I don’t know if that had any impact on this. If the circuit wasn’t protected, maybe it would have welded? I don’t know.
Does your router have a ground fault? 
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No…because when I bypassed the switch and plugged directly into the power line (same circuit), the GFCI did not trip.
Now that I’ve taken the magnetic switch out of the loop and hooked it all up through a paddle switch, all is working just fine. The problem was definitely the magnetic switch and the router combination. I’ve systematically ruled out the other variables.
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It’s possible that the magnetic switch has a ‘leaky’ noise suppressor circuit which was false-tripping the GFCI (RCD) with filter capacitors going to ground.
It was a cheap one. Although, I did run the shapeoko and laser through the switch successfully. It was only when I fired up the router that things went south.
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Yep, routers create quite a lot of electrical noise thanks to their sparky little commutators and a cheap filter could well end up upsetting a GFCI.
But I wonder why the GFCI doesn’t trip if the switch is out of the circuit… The setup is:
Circuit Breaker -> GFCI -> Magnetic Switch -> Socket-> Router === TRIPS on Start up
Circuit Breaker -> GFCI -> Socket -> Router == No problems
I suspect (can’t be sure without prying open your magnetic switch in a warranty voiding way) that the magnetic switch has one or more capacitors, possibly to help reduce contact arcing with noisy inductive loads to avoid the switch just getting melted after a few turn-off events by the contact arcing.
It’s not uncommon to have these sort of simple noise filter / arc suppressor circuits end up ‘leaking’ power to ground asymmetrically and tripping out the current comparing device (RCD / GFCI).
Most GFCI / RCD devices work by some variant of comparing the Live and Neutral lines with a differential current transformer, thus getting a (live current - neutral current) signal to say “some power is leaking out somewhere” and trip. It’s quite easy to cause these to ‘false’ trip with a combination of high-frequency harmonic noise (commutators and inductors) and some capacitors intended to filter out the noise, especially if those capacitors go to ground and not just between live and neutral.
There’s quite a known problem with VFDs either tripping GFCIs or worse, making them insensitive to real faults by swamping them with noise which causes electricians quite a bit of trouble, this is sensitive to the input filtering on the VFD.
I doubt that it is anything specifically ‘wrong’ with any of the components, just that whatever snubber / noise filter is in the magnetic switch is interacting badly with the downstream noise of the router and the upstream GFCI.
If the GFCI isn’t bothered about the router when directly connected I would suspect an unwanted interaction rather than a fault, assuming the router isn’t damaged, dodgy power cord etc. which you seem to have already considered.
Let’s not forget the framazoid. The problem is usually in the framazoid.
When I get faced with a problem like this, I usually just divide by the page number…and everything has a way of working out 
At this point, I’ve got my kill switch installed. I’m just looking for a regular old safety switch that won’t accidentally be thrown by someone leaning against the table to change a router bit (namely, me). Something that has a recessed start button, but not another paddle switch (my total system kill is a paddle and I don’t want two on the same surface). There are many of them…just considering esthetics now.
Thanks for the help!