This is the first time I have used Knots. I would like to change the push on, push off switch on my Powermatic 66 cabinet saw to a large, much easier to use on off switch. When I have large sheetgoods, I can’t reach the switch, as it is located just under the table. And when I have one of those projects requiring frequent on/off motions, the tiny pushbutton controls hurt my arthritic fingers after a few hours. I’ve looked for new switches without much success. I saw a neat big red button in someone’s shop that you hit with your toe, and I wonder if a big green button to the left of the red one to kick the saw on would be even better – sort of like driving a car… on with the left foot, off with the right…
I wonder if anyone out there has tried this, and where you got the parts. I want something safe and easier to use with sheetgoods. I also wonder what I have not considered.
Replies
Risky
A foot switch that would start a saw has some serious safety problems.
Sounds like you have inadequate support for your work. Are you wrestling with a full sheet, getting it up on the saw and then trying to turn on the saw? After the cut, you are trying to control the pieces by hand and then turning the saw off? Neither of these is a situation you want to find yourself in.
You should have sturdy support for the sheet, both starting and finishing the cuts. Most of us have outfeed tables but you may need an infeed table or other means to support the sheet when starting the cut. Your outfeed table may not be wide enough to support both the work and the waste piece. Many times, I cut the heavier sheets to a smaller, more manageable size on saw horses with a portable circular saw. The cut seldom has to be perfect since you will be re-cutting it on the table saw. When I choose to muscle up a full sheet, I have supports I can put in place so the sheet will lay up there without assistance. I may have to duck under to reach the switch. It doesn't take much to build or extend the legs on some sawhorses to the height of the saw, there are penty of other options, too.
There are aftermarket switches with large off buttons that can be activated by your knee. Most modern saws have this type of switch.You may have to position it in an easy to reach place on the saw. Take it from my sewn on thumb, you don't ever want an on switch that can easily be activated, foot, finger or otherwise. You also never want to trust a switch when changing blades or doing other such work, unplug it, then double check that you pulled the right plug. Whenever you find yourself in a situation where the work is difficult to control or you just feel uncomfortable, stop what you are doing and find a safer solution. Surgeries are usually more expensive and time consuming than setting up shop aids.
off/on switch
I guess I didn't make myself clear. Yes, I have adequate support for sheet goods both in and outfeed. But, I don't like to take my eye off the sheetgoods to look under the rail for the tiny push button on/off switch. You have to reach under the sheet goods -at least when it is a sheet that lies to the left of the blade -to turn the saw on - in that split second, the sheet goods could change position as the saw comes on. Newer saws seem to have much better switches, but I can't find a way to buy one from the saw mfg. I saw a switch that nestled in a sturdy box; it could only come on or off if you deliberately kicked it. It was way under the saw, so I can't see how I could accidentally turn the saw on as I never have a reason to have my feet that far under the saw. Perhaps if someone had children who might investigate it might be a problem, but no children ever come into my shop. I usually turn off the power to the shop when I leave, anyway, via the master breaker that turns all but the lights off.
I'd like to be able to give my full attention to what is happening above the saw, and give a swift kick to the on switch with my foot. I looked at a large knee off switch sold for tablesaws, but it was only for 120 v. and I have 230.
(BTW - always, always unplug, or in my case turn off the breaker, when you change blades. I read somewhere that with magnetic switches, a sudden sharp movement can turn on a magnetic switch.)
I'm solidly with the other posters regarding the on button but some wokers fasten a fairly large paddle to the saw in front of the switch to actuate the off button. It is good to be able to easily turn the saw off at any time.
Paul
Better "OFF" switch.
I made this oversized switch for my saw. I usually turn the saw off with my thigh without even looking. I think every saw should have one.
Chris.. I think a great post.
I am NOT any type of safety expert. However, I use a knee operated ON/OFF switch like you have. I tried one on top of the fence but that idea sucked! Yes, more money to spend on a saw.. But I think every table saw should have some type of electronic brake to will stop the blade in a few moments. NO, I am not thinking of the 'instant stop' like the SawStop... AND I have nothing against the SawStop.. I could never afford to purchase it... OK, I could if I gave up feeding my old dog for several years... I would give up feeding myself before my old yellow lab... He is very stubborn, like I am, but we have never bitten anybody.. even if we wanted to do at the time...
And then again,, No spinning sharp object is safe,,, Ever!
Brake
Will,
Yes, I remember the saw we had at LV before we got a Sawstop. It was a cheap Delta contractor's saw which I recall took about ten seconds to coast to a complete stop. Horrible. I have no idea why though. Perhaps impropper belt tensioning? I never used the saw, only saw it being used. I do like the Sawstop and don't mind the guard, except when creating small offcuts which get caught in the guard and the saw must be stopped to clear the offcut before starting again.
I do like the Sawstop and don't mind the guard, except when creating small offcuts which get caught in the guard and the saw must be stopped to clear the offcut before starting again.
You DO have a point.. My old saw will just fling off that offcut into my face.. I have safety glasses and sometimes hit in the forehead by the flying object...
Step aside, wood coming through!
Will,
If the offcut is hitting you in the forehead, I think something is not right! The unguarded saw in my home shop would just leave the offcut sit on the table unless it gets wedged between the blade and throat plate (possible even with a zero-clearance insert) - then I have to turn the saw off to clear it. The offcut should not be fired back at you, especially not upwards. I'm guessing it gets trapped between the blade and the fence?
OMG
You used power tools at LV? I'm shocked! ;-)
tablesaw off on switch
Thank you all for the great information! I like Chris and Sarge's solutions - especially Sarge's door hinge and $3 cost! You guys have to realize, the switches you have on your machines are HUGE compared to the tiny little 1/4" x 1/2" push buttons in the switch on my machine. I have had this machine for maybe 15 or 20 years now and it has never had a problem, so I hesitate to change switches or starters and create new problems for myself. But, I am tired of trying to locate that tiny button and it takes quite a bit of pressure to push it on or off, so I think it is time. I am looking for a larger button, actually. That led to changing the location to a foot operated button... I originally thought I could just contact Powermatic and order a new switch, but there is no place on their website to do so, and after reading these posts I guess I need an electrician. But, how do I find an electrician who is familiar with tablesaw induction motors? And, where does he order the parts? ( I already checked the warehouse the electricians in the area use, and they don't have anything that will work for a tablesaw - I guess they just do buildings and such. So it must be special parts, and where do you get them?)
I copied all the information you provided, so I can properly "vet" an electrician. Next, I have to find someone - how? Will any electrician have this knowledge, or do they need special training beyond their apprenticeship, journeyman, master electrician? I once hired a master electrician to install an electric stove, and he forgot to properly ground the stove. We used the stove for quite a few years before we started getting an electric shock from it, and discovered his mistake. So just hiring any master electrician is not the answer.
The switch on your machine is just an ordinary magnetic starter switch, you could substitute a similar switch made by a dozen other manufacturers, and some switches will work more easily than others. You can also reposition the switch easily enough and place more than one switch on the machine, including one at floor level, if you wanted to get fancy about it.
You will need to talk to an electrician who has some experience with machine wiring to get a recommendation for a switch or switches that will work well for your application.
And most, if not all of our printing presses had 'The switch on your machine is just an ordinary magnetic starter switch'..
And now we have a Lawsuit for a million and something at a common electrican that never used a table saw..
Sure wish I was on the Ryoby Jury trial.. I would have told the other Jury members to pay for 'HIS' mistakes.. As in medical expencies only. I am being very lenient to what he did on his own.. I care less where he came from... It is NOT a issue for me. Stupid is stupid.. I have been stupid sometimes and never blamed it on another!
Hi, ME. Some years back, I heard about a fellow trying to develop a helmet interface that would allow mind control of Inca machines, similar to the weapons interface in the Russian jet in the movie "Firefox". Unfortunately, we'd have to think in Swedish. ;-)
As John suggested, you might consider relocating the control, or creating a secondary control on the in-feed support structure. I think you'd want to be sure that the ON button was well protected from accidental activation, however. I, too, am a big fan of the large paddles for off switches.
This is the first time I have used Knots.
I will warn you that we sometimes go off the deep end.. But we NEVER mean ANY harm to any woodworker or to anybody else.. That uses any tool..
And then you said.. Red buttons..
Sorry I had to reply.. I am old, so I remember Red Buttons on film and sometimes on TV..
Sir, be patient and relax a bit...
Switch Rating
Be careful of the rating when you change the switch. You can't size a starter for an induction motor by looking at the nameplate amps. Inductive loads are much more difficult to interrupt than resistive loads. Use the wrong switch and you could damage your machine, your shop or yourself.
I see paddle switches in Rockler's catalogue and elsewhere. They are always rated in amps. I called Rockler and asked for the HP rating. They didn't know what I was talking about.
My advice would be to get a qualified electrician with knowledge of the National Electrical Code to help you out. If you do it right the fix won't be cheap, but it will be safe.
Best regards,
Fred
Switches and switches.
The switch in the Rockler catalog is a simple on/off switch it doesn't contain offer any protection at all for the motor. It is fine for portable and benchtop machines with universal motors, but it shouldn't be used to control large induction motors that would be on a cabinet style table saw. Induction motors need the type of switch that is commonly referred to as a magnetic switch.
Magnetic switches are set up for the rated draw of the motor they are attached to. On some switches this is accomplished by an adjustment knob inside of the switch housing, while on other switches a small part called a heater, sized for the motor it is protecting, must be installed in the switch. A properly adjusted magnetic switch will protect an induction motor against both sudden overloads and damage from being run too long at too much of a load.
A basic 15 amp switch, like the one in the Rockler catalog, should in theory be able to handle a motor of up to 1 3/4 horsepower, but it would probably suffer from burned contacts after only moderate use connected to that large of a motor.
I agree w/ John
You are right, John. Thermal, (or running, or overload) protection for an induction motor must be provided along with short circuit protection. Switches don't address either of these required protections. They are just on/off devices.
Article 430 of the National Electrical Code, (NEC) is the minimum acceptable guide, in the US, for sizing motor circuits and protection.
Some low HP motors today are internally thermally protected. They don't require external thermal protection. The heaters are built into the windings. Internal running protection is usually not adjustable. Motor short circuit protection is provided by a breaker or fuse.
If you put the whole package together, motor disconnect, short circuit protection, switch, heaters, etc. you get a Motor Starter. Starters can be magnetic or manual. A magnetic starter contains an electrically operated contactor that uses an electromagnet to close the motor circuit. A manual starter replaces the contactor with a hand operated switch.
The basic switch from Rockler would be very dangerous if applied to a table saw.
Best regards,
Fred
I like Chris's switch but... not sure how he gets to the ON switch easily as it seems to be hidden. Here's my paddle attached to a door hinge attached to the front rail. Cost .. about $3. I did do a cut-out on mine so see the ON swithch when using it.
Not a push-button switch like yours
Sarge,
My switch looks kind of standard light switch with a cover over it. Lift from below the cut-out to turn it on, hit the cover to turn it off. I couldn't easily find a picture of one though.
1 vote big paddle like "Sarge's"
He posted when he made it or needed to comment on it a bit ago... and I made one.
Drill holes under your fence guide and tap them to the right size and hang the paddle.. Or if your switch is already mounted that way, buy longer bolts and make a plywood base for your paddle and remount it.. you can cut out a "Start/Run" area in it and make it as big as you want. You want it to work, but not work so great that it turns off alot when you dont want it too. so you may actually get frustrated until you noodle that out. Your looking at I bet scrap you already have and a pair of hinges.. or a single one.
Why make this so hard...
Rich
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