poor man's fein/festool vac load sensing switch

[Sam Shank]

Does anyone know of plans or is anyone smart enough to design a load sensing switch like those in the fein and festool vacs that turn the vac on when it senses a load from your tool that is plugged into the outlet that is part of the vac?

I would guess a simple relay could do this, but I'm too ignorant to figure it out myself. Does someone make a power strip or extension cord with this feature built in?

Thanks!

Sam

[Peter Pedisich]

Sam,

Do you mean like this?
I have one from Rockler (Woodcraft also has it) and it is GREAT!
http://www.woodcraft.com/images/Family/web5855.jpg

[Sam Shank]

Exactly like that, but not $35. The relays only run $10ish from grainger, and outlets and plugs and boxes are pennies. Maybe $15 to make one - if you have the smarts (which I do not in regards to relays.)

[Gary Keedwell]

So let me get this straight. You don't want to spend $400-$500 on a vacuum and someone suggests $35 and you still ain't happy?:confused: :rolleyes:

[Alister Orme]

$19.99 I found one in a sears hardware store.
http://www.sears.com/sr/javasr/product.do?BV_UseBVCookie=Yes&pid=00924031000&cat=Power+Tool+Accessories&subcat=Tool+Safety&vertical=TOOL&ihtoken=1

[Gary Keedwell]

$19.99 I found one in a sears hardware store.
http://www.sears.com/sr/javasr/product.do?BV_UseBVCookie=Yes&pid=00924031000&cat=Power+Tool+Accessories&subcat=Tool+Safety&vertical=TOOL&ihtoken=1
There you go...saving another $15......:rolleyes:
Gary K.

[Matt Meiser]

Sam, you would need more than a relay to make one. The Sears one works great. I briefly had one before I bought my Festool vac.

[Todd Jensen]

I've also used a couple of the Sears $19.99 units - a good price for not having to reverse engineer the thing. It has a 5 second clean-out delay and allows for 2 vacuums/accessories.

Here is my 'Festool' setup:
http://i191.photobucket.com/albums/z66/grizzified/festoolshopvac.jpg

[Kim Spence]

Sam - I was thinking of making the same thing some time back. I vaguely remember reading an article in one of the WW magazines, believe Fine WW, that showed how to make one. But when I searched through my old magazines I of course couldn't find it. Some searching on the web didn't turn anything up either. But I'm almost positive a plan is out there somewhere.

Does anyone else recall seeing this article?

[Sam Shank]

I'll check out sears. I thought it might be a good opportunity to save a few bucks and learn something. You know - a side project type thing.

The link to sears has an expired cookie. It's item number 00924031000 "craftsman auto switch"

And, yes, I am that CHEAP!

[Matt Meiser]

I can't for the life of me figure out how you would do this with just a standard relay. Relay's essentially sense potential (i.e. voltage.) For this application you need to sense current. There are current sensing relays, but I couldn't find them at Grainger.

The fact that the commercial units run the vac for an extra couple seconds is a significant advantage too, especially with something like a biscuit joiner.

[Steve Clardy]

$19.99 I found one in a sears hardware store.
http://www.sears.com/sr/javasr/product.do?BV_UseBVCookie=Yes&pid=00924031000&cat=Power+Tool+Accessories&subcat=Tool+Safety&vertical=TOOL&ihtoken=1

THats what I use.

[Todd Jensen]

Here is the Sears information:
Sears item #00924031000 Mfr. model #24031

and it looks like this:
http://i191.photobucket.com/albums/z66/grizzified/SearsAutomaticSwitch.jpg

http://www.sears.com/sr/javasr/product.do?BV_UseBVCookie=Yes&vertical=TOOL&pid=00924031000&cat=Power+Tool+Accessories&subcat=Tool+Safety

[Gary Curtis]

After two days of looking, I found the magazine article describing how to make this bugger. Fine WoodWorking Issue # 143, August 2000.

Gary Curtis:)

[Bruce Wrenn]

After two days of looking, I found the magazine article describing how to make this bugger. Fine WoodWorking Issue # 143, August 2000.

Gary Curtis:) In 2000, current sensing device from SSAC was about $40, relay from Grainger was about $15, and cube timer (delay on off) was about $20. so for about $75 (in 2000 dollars), you can build a device that retails for $15- $20. Wow, what a savings! I have this very set up in my panel to control DC unit. Never have to look for a remote. Comes on automatically and goes off the same.

[Matt Meiser]

But you'd have the satisfaction of saying you made it. And you could probably find some kind of new tool that you would NEED to buy for the project :D

Grainger doesn't carry the current sensor used in the project any more either. They do carry a more expensive one at about $75.

[Sam Shank]

Here's a link to a guy who built one for his stereo. I think it could be modified to handle more amps.

http://sound.westhost.com/project79.htm

[John Seiffer]

I have the Sears one. It was about $20. Works great.