Dim a Sawzall

[Steve B]

I am going to cannibalize a Sawzall to crack pecans. I need to slow it
down. If I use a dimmer, will that be adequate, and work? Or do I need to
go with a larger rheostat?

Steve

[The Daring Dufas]

1,000 watt 120 volt AC light dimmer? It should handle around 8 amps. ^_^

TDD

[Hench]

what if his sawzall is 9.5 or 10 amps....

[tra...@optonline.net]

I think a lot depends on how the existing speed control
works on the Sawzall and how it reacts to a
chopped sine wave like you'd get from a triac based
light dimmer and how it reacts to reduced voltage like
you'd get with a rheostat.

[Hench]

Wait a minute here: what if the sawzall is powered by 18 volt battery?
OP never said what powered his saw.

[tra...@optonline.net]

On Feb 16, 11:04 am, Hench <ido...@know.ca> wrote:

>   OP never said what powered his saw.- Hide quoted text -
>
> - Show quoted text -

Since he said the choices were a dimmer or a rheostat,
I assume we're talking AC, because dimmer to me implies
a typical dimmer for incandescent lights. Also, it would
be considerably more involved to get either into a cordless.

[cl...@snyder.on.ca]

On Fri, 15 Feb 2013 22:47:50 -0700, "Steve B" <ste...@gmail.com>
wrote:

A dedicated speed control will work better than a lamp dimmer because
of the inductive component of the universal motor in a sawzall. A
rheostat will be your least effective solution - a big Variac would
work better - but remember, you will reduce the power of the motor by
a whole lot more than you reduce the speed. What youreally want is a
variable speed sawzall.

[The Daring Dufas]

Find an old autotransformer dimmer like those used in old time theaters.
I used the bench top version autotransformer in the
TV repair shop I worked in years ago. ^_^

https://en.wikipedia.org/wiki/Autotransformer

http://tinyurl.com/czststb

TDD

[Jon Danniken]

A variac does work, but the motor will slow down when a load is applied.
This is one of the benefits to a phase angle controller; because the
motor still gets full voltage, there is far less speed variation when a
load is applied.

I guess it would depend on exactly how the unit was repurposed; maybe
the load used for cracking pecans would be so low that the variac would
work just fine (and then you have an excuse to buy a variac if you
didn't have one before).

Jon

[tra...@optonline.net]

Aren't all sawzall variable speed? At least the ones I've used all
were.

[Larry W]

It may not, since they are designed to work with lighting and typically the
AC current sine wave. Since they're so cheap, why not try one and see? If
it doesn't work, look for a "router speed control" or similar that is
specifically designed to work with the series-wound motors used in most
hand-held power tools.


--
When the game is over, the pawn and the king are returned to the same box.

Larry Wasserman - Baltimore Maryland - lwasserm(a)sdf. lonestar.org

[John C]

lwas...@sdf.lNoOnSePsAtMar.org (Larry W) wrote in
news:kfp0v2$ed9$1...@speranza.aioe.org:

> In article <kfn6i2$6ks$1...@speranza.aioe.org>, Steve B
> <ste...@gmail.com> wrote:
>>I am going to cannibalize a Sawzall to crack pecans. I need to slow
>>it down. If I use a dimmer, will that be adequate, and work? Or do I
>>need to go with a larger rheostat?
>>
>>Steve
>>
>>
>
> It may not, since they are designed to work with lighting and
> typically the AC current sine wave. Since they're so cheap, why not
> try one and see? If it doesn't work, look for a "router speed control"
> or similar that is specifically designed to work with the series-wound
> motors used in most hand-held power tools.

That would cost $$. If the cheapo was willing to spend a few bucks he
would do it right like a man and buy one of these

<http://pecannutbusters.com/>

That's not going to happen.

[Nate Nagel]

My first thought would be to use a variac, but those aren't cheap.
However they are handy to have around if you're the type of guy who
likes to mess with stuff and/or plays with vintage electronics.

nate

--
replace "roosters" with "cox" to reply.
http://members.cox.net/njnagel

[DerbyDad03]

Have you considered a speed control made for a router?

http://www.harborfreight.com/router-speed-control-43060.html

I'm not guaranteeing anything...

[gregz]

I thought most were ac/dc and had brushes. They used scr control many
times, not triacs. I looked up a couple, use ac/dc. Whats the label say ?

You can buy cheap variable saws.

Greg

[gregz]

Should work for an ac/dc device. It says that somewhere, but not
necessarily in that page. They do say 250 volts dc. ?


I'm not sure, but a rectifier should reduce speed, but I would never try
something without testing with variac or other series load control.

Greg

[larrymo...@my-deja.com]

Forget about a rheostat because you'd need one rated for at
least 1,000 watts, maybe 1,800W. Most light dimmers are
also limited to about 600W, an exception being....the dimmer
built into your Sawzall. Consider cannibalizing it by
replacing its potentiometer (variable resistor) attached to
the trigger with regular rotary potentiometer of the same
ohms rating, taper (linear or logarithmic), and power
rating at least as high (most chassis mount pots are
just 1/2W - 1W, while wirewound ones are 5W). However
any external potentiometer will have to be electrically
isolated because it will be attached directly to a 120VAC
source. You'll have to attaching it to something like
plastic or wood and make sure its metal shaft can't be
touched (plastic knob with NO set screw sticking out --
the set screw should be sunk deep in its hole and the
top of the hole covered with plastic). Another
possibility is control through something optically
isolated. Here's something that explains it:

http://www.fairchildsemi.com/an/AN/AN-3006.pdf

[Dean Hoffman]

On 2/16/13 4:39 PM, John C wrote:

> That would cost $$. If the cheapo was willing to spend a few bucks he
> would do it right like a man and buy one of these
>
> <http://pecannutbusters.com/>
>
> That's not going to happen.
>

Yeahbut. Where's the fun in buying a pre-made nutcracker?
Men don't climb Mt. Everest to see what's there.

[Oren]

LOL

After the video there is another link selection. A nut cracker that
uses a 1/2 inch drill. A smaller unit.

What ever happened to the days when a man cracked two pecans at once
in a cliched fist?

[cl...@snyder.on.ca]

On Sun, 17 Feb 2013 01:51:14 +0000 (UTC), gregz <ze...@comcast.net>
wrote:

AC/DC with brushes IS a universal motor, and they have a significant
inductive component to them..

[Steve B]

"Oren" <Or...@127.0.0.1> wrote in message
news:pgo0i8dk6rjhqj25o...@4ax.com...

When I look at the $15,000 models, my mind starts thinking, and I'm sure I
could cobble together one for a few hundred bucks that would work just fine.
And, there's nothing wrong with cracking pecans with your hands. It's just
tiring with thousands of pounds of them.

I remembered that there is a SawZall with a variable speed (IIRC, and it
wasn't a dream), and that could be altered to work. I just need about 1/8"+
of contact with the ends of the nuts to crack them. Shelling and cleaning
them will be the fun part to the project. That, and figuring out how to
make them fall into a straight line, but I already got that solved.

Steve

Steve

[CRNG]

On Sun, 17 Feb 2013 08:51:51 -0700, "Steve B" <ste...@gmail.com> wrote
in <kfquad$4ub$1...@speranza.aioe.org> Re Re: Dim a Sawzall:

>When I look at the $15,000 models, my mind starts thinking, and I'm sure I
>could cobble together one for a few hundred bucks that would work just fine.
>And, there's nothing wrong with cracking pecans with your hands. It's just
>tiring with thousands of pounds of them.

That looks like an income producing opportunity to me.

[justwe...@gmail.com]

I bought this on eBay and initial response it doesn't work for my harbor freight sawzal, so I have to do more testing and verify that it works as stated. I will definitely let you know what I find out.



http://www.ebay.com/itm/110V-AC-SCR-Electronic-Motor-Speed-Controller-Dimmer-Control-Governor-Thermostat-/141189936741?nma=true&si=1Jg5XBLH9qyX80gTstEVQcFC2rw%253D&orig_cvip=true&rt=nc&_trksid=p2047675.l2557

[Luke C Feur]

You handicapped bag of cocksucking mother fucking shit need you brains bashed in