Miter Saw Push Button

"...that way it is a two hand operation...."

An anti-tiedown switch setup?

that way you have to use both hands to control the saw, left hand for the push button and the right hand for the miter saw....thanks

Put a push button switch in-line on the AC power cord.

I would buy a short heavy duty extension cord, a NEMA box and a correctly rated push button switch to mount in the box, but there may be an off-the-shelf device already available.

I have seen some industrial applications where they mount that box on a wall above the machine.

You can buy something at McMaster-Carr that all you need to do is wire it up. I would use part number 6156K41.

Will the saw blade brake operate if the AC power is interrupted? If no, this is probably not a good solution; use the new safety switch in series with the existing trigger switch located in the saw grip.

Agree that an industrial control should be used.

Depending on the location, If you fall under OSHA, etc. a plug-in extension cord may not be legal.

There may also be legal/insurance implications to modifying an existing piece of equipment.

Something to consider.

I agree that the extension cord is probably not the best idea. I would hard wire the box in place and add a dedicated receptacle just for the saw.

I can not say what legal or insurance ramifications that would carry, but it is the least invasive method to achieve the poster's requirements. You do not need to modify the saw in any way, just install the switch as per electrical code.

Dip into the Americans With Disabilities pool...hire one armed workers: http://www.dol.gov/dol/topic/disability/ada.htm

Seriously, think of the good press you would get!

thanks for the replys....I was planning to interupt the original switch and put the push button in front of it, wasnt sure if this would work or not.

How about a foot operated switch?

I thought this was to make it into a two-hand control for safety ?

"How about a foot operated switch?"

Yes, that way you can cut off BOTH hands!

I don't know if I coulld get my foot that high. Assuming the saw is mounted on a 3 foot table.

yes, it is for safety reasons

Miter saw has always been a two handed operation. One to hold the work, the other squeezes the switch and pulls the handle down to cut.

Are there claps to hold the work? If not then the operator in taking his hand from the work is also a safety issue. Will also lead to poor miters.

Pneumatic clamps, momentary push button switch to activate clamps and pressure switch to insure part is clamped wired in series with saw trigger switch. This set up allows the operator to clamp work as needed. One positioning the other depressing the switch for the clamp. Once clamped it frees the other hand to cut while the other is depressing clamp button.

When I was in college in the 70s I worked at Sears selling power tools. I had a guy come in with one arm to buy a new radial arm saw. He had destroyed his in a fit of rage because he was making repetitive cuts against a jig, but got to the end of a board and had untinkingly moved the short end work piece into the jig on the saw table to where the saw came across and he cut off is arm just above the wrist. He still had to finish the project though so he was buying a new saw. He even joked that one good thing was that he couldn't do that again!

The problem is that you must know the way the miter saw motor is powered via the switch in the handle. If the motor power goes directly through that switch, then whatever switch you put in series with it must also have a MOTOR rating suitable for the saw motor starting. Standard off-the-shelf push buttons may not. If the motor is powered through a relay and the switch just controls the relay, that would be easier to interrupt.

A better approach would be to not disassemble the miter saw at all and use the extra input as a power enabling device, i.e. through a properly rated relay or contactor (depending on the size of your motor). Using a "Safety Relay" may be a requirement in some jurisdictions anyway. Hard wire the miter saw power connection into the relay (in a box of course) and then control the relay with a switch. That box can then be plugged in anywhere to get power to it.

Personally, I like using capacitive switches as the "two hand" control interlock. Mechanical switches can be easily defeated by jamming something into it or taping them down. Capacitive need flesh to be touching them and also don't need force to operate, which can lead to fatigue and increase the likelihood of someone looking for a way to defeat it.

Link

there is a manual clamp to hold the piece that is being cut and also a fence in front and back, we will be cutting the same size material at all times, so, no need for adjustment on the fence.

Doorman you have too much time on your hands. But I do like your idea you could not forget to clamp it down that way, a lot safer for the really simple operation/operator

Good idea!

Add a light curtain such as we use on metal shears and breaks that detect any intrusive object in the path of the saw including hands or fingers or feet to prevent and/or stop the saw operation.

A search on "light curtains for personnel safety" will reveal several suppliers.

Manual clamp?

You already see the need of a device to keep their hands away from the blade. In repetitive tasks the mind has to be focused. Or mistakes are made like getting cut. So that said what makes you think that this manual clamp will be applied every time. The work being kicked out from the saw can be just as injurious or more so.

What's in post 12 works. I have one set up like that.

thanks to everyone that replied back, I appreciate it...I think I got it figured out.

Just wire a normally open push button in series with the saw's own switch; make sure the amp rating is adequate. The clamping system you mention is needed to allow both hands to be free for operating the switches.

I used a miter-saw professionally for many years and

it's my opinion that I want one hand on the trigger

and the other one free to hold the work piece...

Maybe a foot switch?

Were it a table saw, you could use the Saw Stop device that clamps the blade if it ever contacts anything like skin. I saw it demonstrated at a trade show. Watch the video, it's impressive.

http://www.sawstop.com/

http://www.youtube.com/watch?v=E3mzhvMgrLE

I don't think they have it for miter saws though.

This is an example of a push button switch that keeps the electricity flowing as long as you hold the button in the on position as soon as you let go the switch turns off.
Here is the URL http://electrical-controls.springercontrols.com/ImgMedium/N5CEM3_N--Page-G6-006.jpg
The switch should be put in between the cord to the motor and the motor itself. It would require holding down the switch in order to give electricity to the safety switch on the saw.

1. The button head should not be red - this is reserved for the machine STOP function.

2. The button head should be flush - otherwise it's much too easy to accidentally or deliberately actuate the switch, with an object. Alternatively (and preferably) a cover should be fitted, e.g.: