External NVR placement on Dewalt 745 after near miss

[EscapingScreens]

Hello,

So I had a bit of a scare last week, I'm not 100% sure what happened, but I think a small piece got caught in the plate and shot off like a bullet. I was using a blade guard and riving knife, but I think the (awful) wood I was cutting split near a knot. No harm done this time. However, I noticed how awful the positioning the off switch is on my saw when I was trying to turn it off while in a bit of a panic. It's recessed, which now seems absolutely idiotic.

The saw lives on a cart, so I was thinking of adding a beefier switch in a more sensible position with a chuffing great button I can whack without thinking. From the replacement switch that's available, it looks like a standard 4 connector spade switch. I'd like to do this "properly", but I wanted to check for opinions.

Option 1: Get a pre-wired one like this. However, then I have two "on" switches, which seems daft.
Option 2: Remove the existing switch, cover the hole with a blanking plate and extend the wires to something like this.

I'm leaning towards option 2, but I'd be interested to see if anyone had an alternative, or strong opinion.

Thanks in advance.

 

[Simon89]

Two switches would be a real pain as they would both have to be pressed at the same time

 

[EscapingScreens]

Two switches would be a real pain as they would both have to be pressed at the same time

I thought they'd have to be pressed sequentially? My NVR knowledge isn't great though.

 

[Yojevol]

All you need is a momentary stop switch (press to break) in series with the NVR stop switch. You can place this wherever you wish. In fact you can have several switches in series. It will break the NVR latching circuit so the current handling is negligible. I had to replace one (panel mounted) on my Felder combo and it cost less than a fiver.
Brian

 

[graham88]

I thought they'd have to be pressed sequentially? My NVR knowledge isn't great though.

Sadly not. You would indeed have to hold them both down at the same time, NVR stands for no voltage release so unless they are getting power, the circuit will break. Option 2 is a big emergency stop button. I've been thinking of doing this myself, I'd wire a stop button from the mains and then run that out to a socket. It won't cut power when there's a power cut but it gives me something to whack with my knee or whatever if something should go wrong. The NVR on the tools will cater for the power loss issue.

I retract this statement. Decided to ge test the theory instead by plugging my bandsaw into a cheap-o router table, works as described by the comment below. However I still believe a nice big emergency stop button is never a bad idea.

 

[flh801978]

You should be able to press them sequentially the first connected to the mains will latch and hold in ..the 2nd will turn the machine on and latch when pressed…pressing stop on either will stop the machine..if power fails both will latch out.

 

[EscapingScreens]

All you need is a momentary stop switch (press to break) in series with the NVR stop switch. You can place this wherever you wish. In fact you can have several switches in series. It will break the NVR latching circuit so the current handling is negligible. I had to replace one (panel mounted) on my Felder combo and it cost less than a fiver.
Brian

That's a good idea. I guess that would be analogous to a wall switch, albeit with a giant button.

Sadly not. You would indeed have to hold them both down at the same time, NVR stands for no voltage release so unless they are getting power, the circuit will break. Option 2 is a big emergency stop button. I've been thinking of doing this myself, I'd wire a stop button from the mains and then run that out to a socket. It won't cut power when there's a power cut but it gives me something to whack with my knee or whatever if something should go wrong. The NVR on the tools will cater for the power loss issue.

I retract this statement. Decided to ge test the theory instead by plugging my bandsaw into a cheap-o router table, works as described by the comment below. However I still believe a nice big emergency stop button is never a bad idea.

Thank you for checking and correcting yourself, not many would be so thorough. I thought it would work in series as it's sensing the voltage, not the current.

 

[Ttrees]

How about making a hinged paddle for the switch?

 

[TomTheToolMan]

I have a 745 table saw. I agree button placement is poor. Been looking on ebay and they sell retrofit paddles that go over the existing button for about £12. Would also be easy to splice a foot mounted estop button into the cable if you thought necessary. I recently added the soft start to mine. Love it. Doesnt feel as harsh or destructive when you turn on

 

[clogs]

pretty sure u can buy a complete NV switch with a large protruding stop button.....

On the same subject I will add a foot switch to my RS wood lathe...hate the idea of reaching around the work piece....

Not quite sure of the make but a HD wood lathe from the US has the switch gear at the tailstock end....grey moment...

Not quite the smartest job but this was a temp mod to my Colchester Student metal lathe switch gear....
The original off switch was in direct line under the chuck....mental....
when it goes back together next year, only a few weeks away....!!!! it will also get a paint job and panic bar just above the the suds tray.....so u can be anywhere near the lathe and turn it off....

The lever is a rachet type gear lever of a 60's ride on mower....it operates the clutch.......
n the beat up paint can is the counter balance for the splash guard......

 

[EscapingScreens]

How about making a hinged paddle for the switch?

I think the buttons are too close and flappy for that to work. I'm not a fan of the position of them from where I stand either as the motion I made was awkward while supporting the work and trying to find the button.

I have a 745 table saw. I agree button placement is poor. Been looking on ebay and they sell retrofit paddles that go over the existing button for about £12. Would also be easy to splice a foot mounted estop button into the cable if you thought necessary. I recently added the soft start to mine. Love it. Doesnt feel as harsh or destructive when you turn on

I'd seen somewhere else someone mentioning the soft start. That might be something I add if I replace the button entirely. Was there a guide you followed?

 

[Lard]

I had similar thoughts (no accident btw) about the switch on my record power table saw in that I had to reach slightly underneath it to turn on/off. In addition I'm left handed and so feel more comfortable working on the opposite (mirrored) side of the blade to most other people.....this means that the original switch was also not readily accessible and so the turning OFF was always a pain.

What I did was to fit a second OFF switch (with a large protruding red button) to the underside of the front fence rail. I'm now able to turn the machine off with my hip by simply pushing against it and even though it's very easy to 'tap' off by hand I often just use the hip action through habit and also because it leaves both hands free to securely hold onto whatever I'm cutting ,until the blade stops, if I ever need to.

I've wired it so that the original switch has to be used to turn the machine ON and, if I ever need to (rarely) can also still turn it off as well.

The new OFF switch has to be reset (twisted) in order for the ON button to work properly.....I say properly because the blade will start to spin up but immediately shuts down. It will only fire up fully after the reset has taken place.

Before you chastise me for that last bit, consider that it's still an improvement over the original setup as, obviously, the original ON switch simply turns the machine on fully anyway.

Works a treat for me.

 

[stuart little]

pretty sure u can buy a complete NV switch with a large protruding stop button.....

On the same subject I will add a foot switch to my RS wood lathe...hate the idea of reaching around the work piece....

Not quite sure of the make but a HD wood lathe from the US has the switch gear at the tailstock end....grey moment...

Not quite the smartest job but this was a temp mod to my Colchester Student metal lathe switch gear....
The original off switch was in direct line under the chuck....mental....
when it goes back together next year, only a few weeks away....!!!! it will also get a paint job and panic bar just above the the suds tray.....so u can be anywhere near the lathe and turn it off....
View attachment 145344
The lever is a rachet type gear lever of a 60's ride on mower....it operates the clutch.......
n the beat up paint can is the counter balance for the splash guard......

My Record Power lathe has the switch tailstock end - ideal if one is a 'southpaw', but in an emergency a right hander would haf to drop the gouge to grab the stop button. I've thought of relocating it to headstock.

 

[stuart little]

I have a 745 table saw. I agree button placement is poor. Been looking on ebay and they sell retrofit paddles that go over the existing button for about £12. Would also be easy to splice a foot mounted estop button into the cable if you thought necessary. I recently added the soft start to mine. Love it. Doesnt feel as harsh or destructive when you turn on

I've bought one of those retrofit paddles for my 745 but not fitted it yet as I've been waiting for a new NVR. I tried fitting a 3-wire soft start, but somehow it didn't work. Something went wrong &'foxtrotted' the switch which now will not latch - press green; motor starts - release green motor stops. Unless I've blown the PCB, I'm hoping it's the switch. ? I've also got me doubts about the soft start module wire pattern/markings that mod. is now abandoned. I've lived with the saw for 7 or 8 years, so I think I can put up with it a few more. I've also been thinking of making the NVR more accessible, time will tell.

 

[Ttrees]

I think the buttons are too close and flappy for that to work. I'm not a fan of the position of them from where I stand either as the motion I made was awkward while supporting the work and trying to find the button.

I see absolutely nothing to go wrong with the buttons, but whether there is a decent
point to bolt a mounting bracket to hold a hinged paddle.
Can you install a plate to go behind the apron and swap out the fence rail bolts
for longer ones ?

Absolutely everything about those portable saws is a recipe for disaster IMO.
I do hope you don't mind affixing it down with a well designed solution,
as if you don't, something like this is bound to happen.

It appears they don't even have holes for mounting bolts, and I'm guessing they don't make/sell brackets for those tubes to lock down to something.
Poor design if so.

I'm sure I could find something similar with a TS, but I ain't looking.

That's not to say I don't think the cast iron stuff is any safer with a larger blade,
and more power, because you could make one of those wee saws absolutely safe.
I'll have to leave it there, sorry bout that rant over.
All the best
Tom

 

[Spectric]

If you are concerned then just fit an easily accessable E stop, not easy on a small machine Push Buttons | Push Button Switches | Screwfix.com.

If anything happens like this I just step away and evaluate the situation, last thing you want to do is panic. Once the wood has been fired then the hazard is gone and you could just turn it off at the wall socket providing you don't have to lean over that saw! If you want to really go ott then you can get a pressure mat that requires your presence / weight to make a circuit, these have to be used as part of a safety system in industrial applications but in a one man shop it might make using the machine less stressful.

 

[EscapingScreens]

Absolutely everything about those portable saws is a recipe for disaster IMO.
I do hope you don't mind affixing it down with a well designed solution,
as if you don't, something like this is bound to happen.

It appears they don't even have holes for mounting bolts, and I'm guessing they don't make/sell brackets for those tubes to lock down to something.
Poor design if so.

The saw is on a stand, so I have some options for mounting onto the 2x4s uprights, which is definitely more accessible. Mine has mounting holes in the tubes to secure it down, but there are a lot of varieties of this saw in different markets, so I imagine some don't.

If you are concerned then just fit an easily accessable E stop, not easy on a small machine Push Buttons | Push Button Switches | Screwfix.com.

If anything happens like this I just step away and evaluate the situation, last thing you want to do is panic. Once the wood has been fired then the hazard is gone and you could just turn it off at the wall socket providing you don't have to lean over that saw! If you want to really go ott then you can get a pressure mat that requires your presence / weight to make a circuit, these have to be used as part of a safety system in industrial applications but in a one man shop it might make using the machine less stressful.

I took it as a learning point, I've got a healthy respect for the saw. I've always taken the approach of: Step away, work out what happened and try to use it again shortly after to not start avoiding it. In this situation, I think I should have checked if the knot was loose, but beyond that it just highlighted a weakness in the design. I'm going to look into the options and weigh up having to modify the wiring vs adding something in-line. The pre-nabbed NVR might be my first call as I'm building a router table, so that's going to be needed anyway.

 

[HamsterJam]

I’d just fit one of these in series.
Push to isolate, twist to restore.
If you put it before the existing NVR switch, the saw shouldn’t restart until you have twisted the emergency stop and pressed the green button again.

Ideally fit in line with power to all sockets then anything plugged in will stop.

https://www.screwfix.com/p/hylec-1d...-head-push-button-isolator-switch-no-nc/63597

 

[Sofa]

So first time post and as this is something I resolved myself this past weekend I thought I would share and move me from a lurker to a sharer. I have the exact same saw and the position of the switch is absolutely awful. Being 6'5" it was meaning i was having to take my eyes off the blade, step back and look for the button instead of keep trying to fumble around with one hand like a like a school boy at the end of year disco.

I first tried a paddle I brought from Etsy that someone had designed and made for my saw on a 3D printer, this was ok but didn't give me the confidence I wanted in terms of strength of switch and location. I went looking on the web and ended up with a similar switch to the one above but this one had a a big paddle and it was obvious what it did.

https://www.amazon.co.uk/gp/product/B0B51FNQQ6/ref=ppx_yo_dt_b_asin_title_o06_s00?ie=UTF8&psc=1
The reason for this was if anything happened to me in my little workshop and someone came in, they would know instantly what to press to kill the machine. I have also now got it positioned so a little tap with the knee kills the machine and my hands stay on the top and my eyes stay on the blade.

I love it and its really given me some ideas going forward on improving safety and flexibility in my new tiny shop.
I will try and take some photos later for you.

 

[blackteaonesugar]

Is your crown guard and riving knife set like in the picture on that dewalt?
You could park your bike in that gap

That's shocking if that's a manufacturers image. You shouldn't be able to see the crown of the blade. Hence the name.