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[email protected] September 10th 07 04:21 AM

how to bypass dremel tool internal variable speed control?
 
I'm on my second electronic variable speed control inside my Dremel
model 395 tool. This one just crapped out with the same temperamental
symptoms as the last one. I need to use the tool tomorrow night, and
would like to bypass the internal variable speed circuitry to simplify
it; maybe buy an external control later.

There aren't any wiring diagrams I could find on the Dremel site. I'm
thinking if I had one for the model 275 tool (single speed) and the
395 (electronic variable speed), I might be able to make the 395 into
a 275 by just jumpering some wires. I'll probaqbly need to at least
retain the variable speed assembly, since the brushes fit into it.

Can anyone help?


Jamie September 10th 07 04:44 AM

how to bypass dremel tool internal variable speed control?
 
wrote:

I'm on my second electronic variable speed control inside my Dremel
model 395 tool. This one just crapped out with the same temperamental
symptoms as the last one. I need to use the tool tomorrow night, and
would like to bypass the internal variable speed circuitry to simplify
it; maybe buy an external control later.

There aren't any wiring diagrams I could find on the Dremel site. I'm
thinking if I had one for the model 275 tool (single speed) and the
395 (electronic variable speed), I might be able to make the 395 into
a 275 by just jumpering some wires. I'll probaqbly need to at least
retain the variable speed assembly, since the brushes fit into it.

Can anyone help?

Obvious, it's junk! Buy a new model dremel.
or better yet, by one of those no name brands
like I did, looks like it's made in the same place
but cost much less!
$29.00 for a complete set of cutters, stones with
variable speed unit.
I think it was "All Trade" or "TradeAll" or something like that.


--
"I'm never wrong, once i thought i was, but was mistaken"
Real Programmers Do things like this.
http://webpages.charter.net/jamie_5


Claude Desjardins September 10th 07 04:46 AM

how to bypass dremel tool internal variable speed control?
 
wrote:
I'm on my second electronic variable speed control inside my Dremel
model 395 tool. This one just crapped out with the same temperamental
symptoms as the last one. I need to use the tool tomorrow night, and
would like to bypass the internal variable speed circuitry to simplify
it; maybe buy an external control later.

There aren't any wiring diagrams I could find on the Dremel site. I'm
thinking if I had one for the model 275 tool (single speed) and the
395 (electronic variable speed), I might be able to make the 395 into
a 275 by just jumpering some wires. I'll probaqbly need to at least
retain the variable speed assembly, since the brushes fit into it.

Can anyone help?



Hi

Just take it apart, I'm pretty sure it's just a "potentiometer"
(variable resistor) so it would only have 3 leads, one from the external
wire to the pot., one from the pot to the motor, and one from the other
external wire to the other lead of the motor.

Cut things off, plug the external leads directly to the motor.

You can make yourself something that would do the same with a variable
light controller (those you have to control your house lights) Get one
of these, one wall plug unit and one extension cord.

PWR IN (1) to VARIABLE (1)
VARIABLE (2) to PWR OUT (1)
PWR IN (2) to PWR OUT (2)

it would be an awesome idea to tape everything together to cover the
connections once you're done so you don't get shocked everytime you want
to slow it down or speed it up :)

Have fun


(PS I also have one of the new Dremel units and it smokes too ... Uh.)

lj_robins September 10th 07 04:54 AM

how to bypass dremel tool internal variable speed control?
 
wrote:
I'm on my second electronic variable speed control inside my Dremel
model 395 tool. This one just crapped out with the same temperamental
symptoms as the last one. I need to use the tool tomorrow night, and
would like to bypass the internal variable speed circuitry to simplify
it; maybe buy an external control later.

There aren't any wiring diagrams I could find on the Dremel site. I'm
thinking if I had one for the model 275 tool (single speed) and the
395 (electronic variable speed), I might be able to make the 395 into
a 275 by just jumpering some wires. I'll probaqbly need to at least
retain the variable speed assembly, since the brushes fit into it.

Can anyone help?


I'm not positive, but I would think if you just soldered a wire around
the speed control it would run at full speed, I could be wrong though.

-Landon

[email protected] September 10th 07 05:00 AM

how to bypass dremel tool internal variable speed control?
 
Just take it apart, I'm pretty sure it's just a "potentiometer"
(variable resistor) so it would only have 3 leads, one from the external
wire to the pot., one from the pot to the motor, and one from the other
external wire to the other lead of the motor.

Cut things off, plug the external leads directly to the motor.



Unfortuantely it doesn't seem that simple. The speed control has what
looks like a some kind of semiconductor/IC (3 leads), a diode, and
maybe a fixed resistor in addition to the slide pot. I don't know if
they're doing pulse width modulation or what.


Trevor Jones September 10th 07 05:01 AM

how to bypass dremel tool internal variable speed control?
 
wrote:
I'm on my second electronic variable speed control inside my Dremel
model 395 tool. This one just crapped out with the same temperamental
symptoms as the last one. I need to use the tool tomorrow night, and
would like to bypass the internal variable speed circuitry to simplify
it; maybe buy an external control later.

There aren't any wiring diagrams I could find on the Dremel site. I'm
thinking if I had one for the model 275 tool (single speed) and the
395 (electronic variable speed), I might be able to make the 395 into
a 275 by just jumpering some wires. I'll probaqbly need to at least
retain the variable speed assembly, since the brushes fit into it.

Can anyone help?


If you cannot figure that out by looking, you probably should not be
dicking around with it.

The last fried speed control in a chinese one I bought, took a buck's
worth of a new triac to fix.

Cheers
Trevor Jones


Claude Desjardins September 10th 07 05:20 AM

how to bypass dremel tool internal variable speed control?
 
wrote:
Just take it apart, I'm pretty sure it's just a "potentiometer"
(variable resistor) so it would only have 3 leads, one from the external
wire to the pot., one from the pot to the motor, and one from the other
external wire to the other lead of the motor.

Cut things off, plug the external leads directly to the motor.


Unfortuantely it doesn't seem that simple. The speed control has what
looks like a some kind of semiconductor/IC (3 leads), a diode, and
maybe a fixed resistor in addition to the slide pot. I don't know if
they're doing pulse width modulation or what.



I doubt they have put a stepper motor in there, they wouldn't sell for
20$ each! -- You still should only have two leads coming out of the
motor. Confirm?


Claude Desjardins September 10th 07 05:22 AM

how to bypass dremel tool internal variable speed control?
 
Claude Desjardins wrote:
wrote:
Just take it apart, I'm pretty sure it's just a "potentiometer"
(variable resistor) so it would only have 3 leads, one from the external
wire to the pot., one from the pot to the motor, and one from the other
external wire to the other lead of the motor.

Cut things off, plug the external leads directly to the motor.


Unfortuantely it doesn't seem that simple. The speed control has what
looks like a some kind of semiconductor/IC (3 leads), a diode, and
maybe a fixed resistor in addition to the slide pot. I don't know if
they're doing pulse width modulation or what.



I doubt they have put a stepper motor in there, they wouldn't sell for
20$ each! -- You still should only have two leads coming out of the
motor. Confirm?


Btw you said there was a IC ... how many pins does it has, can u give
out the ID (in case it's a bridge or something so your motor would be DC
(Uhm?!) and wouldnt be a great idea to plug it right into a wall outlet!

James Sweet September 10th 07 06:27 AM

how to bypass dremel tool internal variable speed control?
 

wrote in message
ups.com...
Just take it apart, I'm pretty sure it's just a "potentiometer"
(variable resistor) so it would only have 3 leads, one from the external
wire to the pot., one from the pot to the motor, and one from the other
external wire to the other lead of the motor.

Cut things off, plug the external leads directly to the motor.



Unfortuantely it doesn't seem that simple. The speed control has what
looks like a some kind of semiconductor/IC (3 leads), a diode, and
maybe a fixed resistor in addition to the slide pot. I don't know if
they're doing pulse width modulation or what.


Of course it's not gonna be a pot, it would have to be far too big and burn
up a lot of power. Instead they use what is essentially a light dimmer. The
semiconductor you see is a triac, the diode is a diac to trigger it, if you
just jumper together the right two pins on the triac, the motor will be
forced on.



William Noble September 10th 07 08:21 AM

how to bypass dremel tool internal variable speed control?
 
the speed control is a triac based phase control, the same as a light
dimmer - typically it has two wires, just short the two wires together and
the dremel will run full speed all the time.

by the way, typical failure is just noisy pot, try cleaning carbon track
wrote in message
oups.com...
I'm on my second electronic variable speed control inside my Dremel
model 395 tool. This one just crapped out with the same temperamental
symptoms as the last one. I need to use the tool tomorrow night, and
would like to bypass the internal variable speed circuitry to simplify
it; maybe buy an external control later.

There aren't any wiring diagrams I could find on the Dremel site. I'm
thinking if I had one for the model 275 tool (single speed) and the
395 (electronic variable speed), I might be able to make the 395 into
a 275 by just jumpering some wires. I'll probaqbly need to at least
retain the variable speed assembly, since the brushes fit into it.

Can anyone help?




--
Posted via a free Usenet account from http://www.teranews.com


Kristian Ukkonen September 10th 07 10:07 AM

how to bypass dremel tool internal variable speed control?
 

William Noble wrote:
the speed control is a triac based phase control, the same as a light
dimmer - typically it has two wires, just short the two wires together and
the dremel will run full speed all the time.

by the way, typical failure is just noisy pot, try cleaning carbon track


Mine had a smd triac BT134W which was faulty.

I replaced it (easy!!) with a new one, and
the dremel has worked years after that. The
triac costs about 1 usd.. The parts are on a
white ceramic circuitboard.

Kristian Ukkonen.

Arfa Daily September 10th 07 10:42 AM

how to bypass dremel tool internal variable speed control?
 

"James Sweet" wrote in message
news:UI3Fi.1085$rw3.1000@trndny04...

wrote in message
ups.com...
Just take it apart, I'm pretty sure it's just a "potentiometer"
(variable resistor) so it would only have 3 leads, one from the external
wire to the pot., one from the pot to the motor, and one from the other
external wire to the other lead of the motor.

Cut things off, plug the external leads directly to the motor.



Unfortuantely it doesn't seem that simple. The speed control has what
looks like a some kind of semiconductor/IC (3 leads), a diode, and
maybe a fixed resistor in addition to the slide pot. I don't know if
they're doing pulse width modulation or what.


Of course it's not gonna be a pot, it would have to be far too big and
burn up a lot of power. Instead they use what is essentially a light
dimmer. The semiconductor you see is a triac, the diode is a diac to
trigger it, if you just jumper together the right two pins on the triac,
the motor will be forced on.

Don' it just hurt to the core, James ... ? !!! ;~)

Arfa



B Fuhrmann September 10th 07 12:35 PM

how to bypass dremel tool internal variable speed control?
 
hillpc wrote ...
I'm on my second electronic variable speed control inside my Dremel
model 395 tool. This one just crapped out with the same temperamental
symptoms as the last one. I need to use the tool tomorrow night, and
would like to bypass the internal variable speed circuitry to simplify
it; maybe buy an external control later.

. . .
Can anyone help?


This is one of those cases where "If you don't know already, you probably
shouldn't be doing the job".

The wiring should be simple enough to do it by inspection. If it isn't, you
really need the schematic and the ability to understand it.

Unlike the other poster, I really doubt that the motor speed control is just
a pot.


--
Bill Fuhrmann



[email protected] September 10th 07 02:25 PM

how to bypass dremel tool internal variable speed control?
 
Thanks, folks. This discussion is exactly the type of info I
needed.


Jamie September 10th 07 06:55 PM

how to bypass dremel tool internal variable speed control?
 
wrote:
Just take it apart, I'm pretty sure it's just a "potentiometer"
(variable resistor) so it would only have 3 leads, one from the external
wire to the pot., one from the pot to the motor, and one from the other
external wire to the other lead of the motor.

Cut things off, plug the external leads directly to the motor.



Unfortuantely it doesn't seem that simple. The speed control has what
looks like a some kind of semiconductor/IC (3 leads), a diode, and
maybe a fixed resistor in addition to the slide pot. I don't know if
they're doing pulse width modulation or what.

That's a simple phase control SCR circuit.
the diode is a DIAC.. etc..
if it's not firing, I would check the pot and
resistor.


--
"I'm never wrong, once i thought i was, but was mistaken"
Real Programmers Do things like this.
http://webpages.charter.net/jamie_5


Michael A. Terrell September 10th 07 07:48 PM

how to bypass dremel tool internal variable speed control?
 
Claude Desjardins wrote:

wrote:
Just take it apart, I'm pretty sure it's just a "potentiometer"
(variable resistor) so it would only have 3 leads, one from the external
wire to the pot., one from the pot to the motor, and one from the other
external wire to the other lead of the motor.

Cut things off, plug the external leads directly to the motor.


Unfortuantely it doesn't seem that simple. The speed control has what
looks like a some kind of semiconductor/IC (3 leads), a diode, and
maybe a fixed resistor in addition to the slide pot. I don't know if
they're doing pulse width modulation or what.


I doubt they have put a stepper motor in there, they wouldn't sell for
20$ each! -- You still should only have two leads coming out of the
motor. Confirm?



Every Dremel tool I've had apart used a universal motor, and the
speed control was a simple dimmer circuit. This one might be PWM, and
run the motor on DC.

--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

Jamie September 10th 07 08:14 PM

how to bypass dremel tool internal variable speed control?
 
Michael A. Terrell wrote:

Claude Desjardins wrote:

wrote:

Just take it apart, I'm pretty sure it's just a "potentiometer"
(variable resistor) so it would only have 3 leads, one from the external
wire to the pot., one from the pot to the motor, and one from the other
external wire to the other lead of the motor.

Cut things off, plug the external leads directly to the motor.


Unfortuantely it doesn't seem that simple. The speed control has what
looks like a some kind of semiconductor/IC (3 leads), a diode, and
maybe a fixed resistor in addition to the slide pot. I don't know if
they're doing pulse width modulation or what.


I doubt they have put a stepper motor in there, they wouldn't sell for
20$ each! -- You still should only have two leads coming out of the
motor. Confirm?




Every Dremel tool I've had apart used a universal motor, and the
speed control was a simple dimmer circuit. This one might be PWM, and
run the motor on DC.

Most of the cordless drills these days use PWM power FeT drivers.

I modified a cordless drill with a mini PIC and Bridge to
perform regulated torque control, auto reverse and then forward
again until maximum torque was no longer peaking. Did this so that
the drill would have a TAP mode in it. I stuck a mini pot on the back
side of the handle to set the torque level.

if his dremel is also cordless, It may also be using it a PWM?
who knows. how ever, with the part count, I'm guessing he's using a
corded unit with a phase control.


--
"I'm never wrong, once i thought i was, but was mistaken"
Real Programmers Do things like this.
http://webpages.charter.net/jamie_5


Michael A. Terrell September 10th 07 09:06 PM

how to bypass dremel tool internal variable speed control?
 
Jamie wrote:

Michael A. Terrell wrote:

Claude Desjardins wrote:

wrote:

Just take it apart, I'm pretty sure it's just a "potentiometer"
(variable resistor) so it would only have 3 leads, one from the external
wire to the pot., one from the pot to the motor, and one from the other
external wire to the other lead of the motor.

Cut things off, plug the external leads directly to the motor.


Unfortuantely it doesn't seem that simple. The speed control has what
looks like a some kind of semiconductor/IC (3 leads), a diode, and
maybe a fixed resistor in addition to the slide pot. I don't know if
they're doing pulse width modulation or what.


I doubt they have put a stepper motor in there, they wouldn't sell for
20$ each! -- You still should only have two leads coming out of the
motor. Confirm?




Every Dremel tool I've had apart used a universal motor, and the
speed control was a simple dimmer circuit. This one might be PWM, and
run the motor on DC.

Most of the cordless drills these days use PWM power FeT drivers.

I modified a cordless drill with a mini PIC and Bridge to
perform regulated torque control, auto reverse and then forward
again until maximum torque was no longer peaking. Did this so that
the drill would have a TAP mode in it. I stuck a mini pot on the back
side of the handle to set the torque level.

if his dremel is also cordless, It may also be using it a PWM?
who knows. how ever, with the part count, I'm guessing he's using a
corded unit with a phase control.



None of those I've seen used an IC in the speed control. Also, he
didn't mention a filter capacitor, so id may be a simple dimmer
circuit. It's hard to tell from such a vague description. Part numbers
would have been a big help.

BTW, have you seen the small DC powered clone at Harbor Freight? It
runs on 12 VDC, and comes with an AC adapter. I was thinking about
using one (or more, with different sized drills) with a homebrew CNC
machine to drill PC boards.


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

Jamie September 10th 07 09:53 PM

how to bypass dremel tool internal variable speed control?
 
Michael A. Terrell wrote:

Jamie wrote:

Michael A. Terrell wrote:


Claude Desjardins wrote:


wrote:



Unfortuantely it doesn't seem that simple. The speed control has what
looks like a some kind of semiconductor/IC (3 leads), a diode, and
maybe a fixed resistor in addition to the slide pot. I don't know if
they're doing pulse width modulation or what.


I doubt they have put a stepper motor in there, they wouldn't sell for
20$ each! -- You still should only have two leads coming out of the
motor. Confirm?



Every Dremel tool I've had apart used a universal motor, and the
speed control was a simple dimmer circuit. This one might be PWM, and
run the motor on DC.


Most of the cordless drills these days use PWM power FeT drivers.

I modified a cordless drill with a mini PIC and Bridge to
perform regulated torque control, auto reverse and then forward
again until maximum torque was no longer peaking. Did this so that
the drill would have a TAP mode in it. I stuck a mini pot on the back
side of the handle to set the torque level.

if his dremel is also cordless, It may also be using it a PWM?
who knows. how ever, with the part count, I'm guessing he's using a
corded unit with a phase control.




None of those I've seen used an IC in the speed control. Also, he
didn't mention a filter capacitor, so id may be a simple dimmer
circuit. It's hard to tell from such a vague description. Part numbers
would have been a big help.

BTW, have you seen the small DC powered clone at Harbor Freight? It
runs on 12 VDC, and comes with an AC adapter. I was thinking about
using one (or more, with different sized drills) with a homebrew CNC
machine to drill PC boards.


Hmm, No, I haven't checked into Harbor Freight in some time how ever, I
think you'll find that a lot of named brand tools we know are now being
made by the same people that make the no-name brands from China.
For example, I have a rotary tool that in all respects is a dremal.
bu t the name isn't of course.
As far as drills with PWM, the Craftsman 1/2 drive chuck cordless uses
PWM driver board which is mounted as part of the trigger. the speed pot
slider is on the board. It employs an IC chip with a logic level Power Fet.

We have some electric real movers that are still being modified by the
manufacturer because they can't seem to get one to last any longer than
2 months in our shop. First they had drive problems where it wouldn't
start half the time. This was an elaborate board with a micro driving
what looked like a Mosfet H-bridge.

Any ways, we sent them back, the next set that came our way, they
modified with the speed control in the handle of the unit. All they
did was employ a speed control trigger slide switch from some existing
cordless drill system.
Those were very simply units, a single Power Fet with a 555 timer
driving it. Not sure if it was variable freq pulsed or PWM? Anyways,
those have a switch in the slide that initially connected the + batt
lead to the Vcc and Drain of the Powerfet. the Minimum speed was too
much on initial start. Those would burned them self's up in the switch.!
oh well, so much for engineering.


--
"I'm never wrong, once i thought i was, but was mistaken"
Real Programmers Do things like this.
http://webpages.charter.net/jamie_5


Claude Desjardins September 11th 07 03:39 AM

how to bypass dremel tool internal variable speed control?
 
Michael A. Terrell wrote:
Jamie wrote:
Michael A. Terrell wrote:

Claude Desjardins wrote:

wrote:

Just take it apart, I'm pretty sure it's just a "potentiometer"
(variable resistor) so it would only have 3 leads, one from the external
wire to the pot., one from the pot to the motor, and one from the other
external wire to the other lead of the motor.

Cut things off, plug the external leads directly to the motor.

Unfortuantely it doesn't seem that simple. The speed control has what
looks like a some kind of semiconductor/IC (3 leads), a diode, and
maybe a fixed resistor in addition to the slide pot. I don't know if
they're doing pulse width modulation or what.

I doubt they have put a stepper motor in there, they wouldn't sell for
20$ each! -- You still should only have two leads coming out of the
motor. Confirm?


Every Dremel tool I've had apart used a universal motor, and the
speed control was a simple dimmer circuit. This one might be PWM, and
run the motor on DC.

Most of the cordless drills these days use PWM power FeT drivers.

I modified a cordless drill with a mini PIC and Bridge to
perform regulated torque control, auto reverse and then forward
again until maximum torque was no longer peaking. Did this so that
the drill would have a TAP mode in it. I stuck a mini pot on the back
side of the handle to set the torque level.

if his dremel is also cordless, It may also be using it a PWM?
who knows. how ever, with the part count, I'm guessing he's using a
corded unit with a phase control.



None of those I've seen used an IC in the speed control. Also, he
didn't mention a filter capacitor, so id may be a simple dimmer
circuit. It's hard to tell from such a vague description. Part numbers
would have been a big help.

BTW, have you seen the small DC powered clone at Harbor Freight? It
runs on 12 VDC, and comes with an AC adapter. I was thinking about
using one (or more, with different sized drills) with a homebrew CNC
machine to drill PC boards.



I took a look at google images for his model and the dimmer really is
just a dimmer ... providing they sell brushes kits (2) for his model,
the principle was ok from the first post; plug it right to the input.

If the person who originally posted the question still follows the
discussion; it is strongly suggested that you do NOT use the tool wired
that way for too long as the motor will overheat and break (or some of
its internals will melt down)... take it as a temporary fix only.

clare at snyder.on.ca September 11th 07 05:01 AM

how to bypass dremel tool internal variable speed control?
 
On Mon, 10 Sep 2007 21:39:17 -0400, Claude Desjardins
wrote:


I took a look at google images for his model and the dimmer really is
just a dimmer ... providing they sell brushes kits (2) for his model,
the principle was ok from the first post; plug it right to the input.

If the person who originally posted the question still follows the
discussion; it is strongly suggested that you do NOT use the tool wired
that way for too long as the motor will overheat and break (or some of
its internals will melt down)... take it as a temporary fix only.



Or do like I did. I took a 600 watt dimmer and put it in a project box
with a cord on one end, and a receptacle on the other. I use it to
control the speed of dremel type tools (anything with universal motor
under about 400 watts) and to regulate output of my soldering iron.
Also comes in handy to dim the occaisional lamp.

As long as you don't run it wide open for long periods of time it will
last as long as if you had the built-in speed control. My luck with
Dremels has been terrible. The cheap chinese crap lasts just as long,
for 1/4 the price. Much as I hate chinese crap.

--
Posted via a free Usenet account from http://www.teranews.com


Tony September 11th 07 05:42 AM

how to bypass dremel tool internal variable speed control?
 
after you make your temporary repair, dremel sells all the parts you might
need for a nominal cost if you call customer service.


wrote in message
ups.com...
Thanks, folks. This discussion is exactly the type of info I
needed.



cavelamb himself[_4_] September 11th 07 08:38 AM

how to bypass dremel tool internal variable speed control?
 
clare at snyder.on.ca wrote:


Or do like I did. I took a 600 watt dimmer and put it in a project box
with a cord on one end, and a receptacle on the other. I use it to
control the speed of dremel type tools (anything with universal motor
under about 400 watts) and to regulate output of my soldering iron.
Also comes in handy to dim the occaisional lamp.

As long as you don't run it wide open for long periods of time it will
last as long as if you had the built-in speed control. My luck with
Dremels has been terrible. The cheap chinese crap lasts just as long,
for 1/4 the price. Much as I hate chinese crap.



I was like that once - long ago.

Then I got my first DIE GRINDER!

OOOOOoooohhhh Baby.

Atomic powered Dremel.

What a TOOL to have in hand. Oh, The POWER!

But warning - this dude ain't for balsa wood, kiddies.

And you probably outta practice on something else before trimming those
gnarly toe nails...



[email protected] September 11th 07 06:14 PM

how to bypass dremel tool internal variable speed control?
 
On Sep 10, 11:55 am, Jamie
t wrote:
wrote:
Unfortuantely it doesn't seem that simple. The speed control has what
looks like a some kind of semiconductor/IC (3 leads), a diode, and
maybe a fixed resistor in addition to the slide pot. I don't know if
they're doing pulse width modulation or what.


That's a simple phase control SCR circuit.
the diode is a DIAC.. etc..
if it's not firing, I would check the pot and
resistor.


Trace it with a volt meter. Probably a bad solder job and the heat
from the controller loosened something up. Easy fix if you have a
decent iron.


Leon Fisk September 11th 07 10:44 PM

how to bypass dremel tool internal variable speed control?
 
On Mon, 10 Sep 2007 23:01:45 -0400, clare at snyder.on.ca
wrote:

snip
Or do like I did. I took a 600 watt dimmer and put it in a project box
with a cord on one end, and a receptacle on the other. I use it to
control the speed of dremel type tools (anything with universal motor
under about 400 watts) and to regulate output of my soldering iron.
Also comes in handy to dim the occaisional lamp.

As long as you don't run it wide open for long periods of time it will
last as long as if you had the built-in speed control. My luck with
Dremels has been terrible. The cheap chinese crap lasts just as long,
for 1/4 the price. Much as I hate chinese crap.


More China crap...

You can get a Router Speed Control from Harbor Freight for
~$13 on sale pretty often.

"ROUTER SPEED CONTROL

Get better results and longer bit life when routing tough
woods, plastics, even aluminum. Plug your router into the
control unit and you instantly have a variable-speed tool.
Works with any universal AC/DC brush type motor, 15 amps and
under. Will not work with soft- or slow-start motors.

ITEM 43060-1VGA"

See:

http://www.harborfreight.com/cpi/cta...emnumber=43060

I have one and it works okay with my die grinder, drill,
table saw (cheapo, has universal motor), 4 inch angle
grinder...

Your going to have a hard time building one cheaper than
this and have it look and work as well.

--
Leon Fisk
Grand Rapids MI/Zone 5b
Remove no.spam for email

Jerry September 12th 07 01:07 AM

how to bypass dremel tool internal variable speed control?
 
On Sep 10, 12:06 pm, "Michael A. Terrell"
wrote:

BTW, have you seen the small DC powered clone at Harbor Freight? It
runs on 12 VDC, and comes with an AC adapter. I was thinking about
using one (or more, with different sized drills) with a homebrew CNC
machine to drill PC boards.


I have one of those HF pseudo-dremels. Not very torque-y at all. Bogs
down very easily. A very light touch is required.

Jerry


Michael Black September 12th 07 01:15 AM

how to bypass dremel tool internal variable speed control?
 
Jerry ) writes:
On Sep 10, 12:06 pm, "Michael A. Terrell"
wrote:

BTW, have you seen the small DC powered clone at Harbor Freight? It
runs on 12 VDC, and comes with an AC adapter. I was thinking about
using one (or more, with different sized drills) with a homebrew CNC
machine to drill PC boards.


I have one of those HF pseudo-dremels. Not very torque-y at all. Bogs
down very easily. A very light touch is required.

But that's the point, those things have really high speed to do the
work, and you shouldn't be using much pressure.

Try sawing through a bolt. You'd have to use the hacksaw and lots
of pressure. Put a cutoff wheel in the "rotary tool", and you barely
need to apply any pressure. The first time I tried a cutoff wheel
in one of those things was the day I realized how wonderful they
were.

Now, your cheap one may have other problems. But a light touch
is what's required with "rotary tools" anyway.

Michael


clare at snyder.on.ca September 12th 07 03:32 AM

how to bypass dremel tool internal variable speed control?
 
On Tue, 11 Sep 2007 01:38:45 -0500, cavelamb himself
wrote:

clare at snyder.on.ca wrote:


Or do like I did. I took a 600 watt dimmer and put it in a project box
with a cord on one end, and a receptacle on the other. I use it to
control the speed of dremel type tools (anything with universal motor
under about 400 watts) and to regulate output of my soldering iron.
Also comes in handy to dim the occaisional lamp.

As long as you don't run it wide open for long periods of time it will
last as long as if you had the built-in speed control. My luck with
Dremels has been terrible. The cheap chinese crap lasts just as long,
for 1/4 the price. Much as I hate chinese crap.



I was like that once - long ago.

Then I got my first DIE GRINDER!

OOOOOoooohhhh Baby.

Atomic powered Dremel.

What a TOOL to have in hand. Oh, The POWER!

But warning - this dude ain't for balsa wood, kiddies.

And you probably outta practice on something else before trimming those
gnarly toe nails...

I've got a good air powered one of those for the "serious stuff" but
the crappy dremels don't even stund up th the "balsa and toenails"
type jobs.

--
Posted via a free Usenet account from http://www.teranews.com


clare at snyder.on.ca September 12th 07 03:35 AM

how to bypass dremel tool internal variable speed control?
 
On Tue, 11 Sep 2007 16:44:37 -0400, Leon Fisk
wrote:

Your going to have a hard time building one cheaper than
this and have it look and work as well.

Built mine about 15 or more years ago in a $2 surplus project box,
using the cord from an old iron and the receptacle from an old
stove-top with a dimmer I picked up in a box of stuff at an auction. I
think total cast was $5 or less and it STILL looks and works just
fine.

--
Posted via a free Usenet account from http://www.teranews.com


Jim Yanik September 12th 07 04:15 AM

how to bypass dremel tool internal variable speed control?
 
(Michael Black) wrote in
:

Jerry ) writes:
On Sep 10, 12:06 pm, "Michael A. Terrell"
wrote:

BTW, have you seen the small DC powered clone at Harbor Freight? It
runs on 12 VDC, and comes with an AC adapter. I was thinking about
using one (or more, with different sized drills) with a homebrew CNC
machine to drill PC boards.


I have one of those HF pseudo-dremels. Not very torque-y at all. Bogs
down very easily. A very light touch is required.

But that's the point, those things have really high speed to do the
work, and you shouldn't be using much pressure.


the motor on a Dremel is a lot bigger than the motor on the Harbor Freight
tool.

--
Jim Yanik
jyanik
at
kua.net

Jim Yanik September 12th 07 04:19 AM

how to bypass dremel tool internal variable speed control?
 
clare at snyder.on.ca wrote in
:

I've got a good air powered one of those for the "serious stuff" but
the crappy dremels don't even stund up th the "balsa and toenails"
type jobs.


I have a Dremel 270 that I've had for 20 years or more.
I have a homemade "lamp dimmer" speed control I often use with it.
It's no "crappy tool".

Maybe the newer ones are,though.

--
Jim Yanik
jyanik
at
kua.net

cavelamb himself[_4_] September 12th 07 04:40 AM

how to bypass dremel tool internal variable speed control?
 
clare at snyder.on.ca wrote:
On Tue, 11 Sep 2007 01:38:45 -0500, cavelamb himself
wrote:


clare at snyder.on.ca wrote:


Or do like I did. I took a 600 watt dimmer and put it in a project box
with a cord on one end, and a receptacle on the other. I use it to
control the speed of dremel type tools (anything with universal motor
under about 400 watts) and to regulate output of my soldering iron.
Also comes in handy to dim the occaisional lamp.

As long as you don't run it wide open for long periods of time it will
last as long as if you had the built-in speed control. My luck with
Dremels has been terrible. The cheap chinese crap lasts just as long,
for 1/4 the price. Much as I hate chinese crap.



I was like that once - long ago.

Then I got my first DIE GRINDER!

OOOOOoooohhhh Baby.

Atomic powered Dremel.

What a TOOL to have in hand. Oh, The POWER!

But warning - this dude ain't for balsa wood, kiddies.

And you probably outta practice on something else before trimming those
gnarly toe nails...


I've got a good air powered one of those for the "serious stuff" but
the crappy dremels don't even stund up th the "balsa and toenails"
type jobs.



Well, balsa is no problem, byt dam, Clare, those toenails....

Claude Desjardins September 12th 07 07:35 AM

how to bypass dremel tool internal variable speed control?
 
cavelamb himself wrote:
clare at snyder.on.ca wrote:
On Tue, 11 Sep 2007 01:38:45 -0500, cavelamb himself
wrote:


clare at snyder.on.ca wrote:


Or do like I did. I took a 600 watt dimmer and put it in a project box
with a cord on one end, and a receptacle on the other. I use it to
control the speed of dremel type tools (anything with universal motor
under about 400 watts) and to regulate output of my soldering iron.
Also comes in handy to dim the occaisional lamp.

As long as you don't run it wide open for long periods of time it will
last as long as if you had the built-in speed control. My luck with
Dremels has been terrible. The cheap chinese crap lasts just as long,
for 1/4 the price. Much as I hate chinese crap.



I was like that once - long ago.

Then I got my first DIE GRINDER!

OOOOOoooohhhh Baby.

Atomic powered Dremel.

What a TOOL to have in hand. Oh, The POWER!

But warning - this dude ain't for balsa wood, kiddies.

And you probably outta practice on something else before trimming those
gnarly toe nails...


I've got a good air powered one of those for the "serious stuff" but
the crappy dremels don't even stund up th the "balsa and toenails"
type jobs.



Well, balsa is no problem, byt dam, Clare, those toenails....


Pneumatic rotary tool at 120psi, should fix a stereo in a matter of
seconds ;) It's a "I fixed it, now go back to radioshack"

Marc Britten October 3rd 07 03:55 AM

how to bypass dremel tool internal variable speed control?
 
On Sep 9, 9:21 pm, wrote:
I'm on my second electronic variable speed control inside myDremel
model 395 tool. This one just crapped out with the same temperamental
symptoms as the last one. I need to use the tool tomorrow night, and
would like to bypass the internal variable speed circuitry to simplify
it; maybe buy an external control later.

There aren't any wiring diagrams I could find on theDremelsite. I'm
thinking if I had one for the model 275 tool (single speed) and the
395 (electronic variable speed), I might be able to make the 395 into
a 275 by just jumpering some wires. I'll probaqbly need to at least
retain the variable speed assembly, since the brushes fit into it.

Can anyone help?


Not to dig up an old topic, but I just ran into this
http://mondo-technology.com/dremel.html


Boris Beizer October 3rd 07 04:44 PM

how to bypass dremel tool internal variable speed control?
 

"Marc Britten" wrote in message
oups.com...
On Sep 9, 9:21 pm, wrote:
I'm on my second electronic variable speed control inside myDremel
model 395 tool. This one just crapped out with the same temperamental
symptoms as the last one. I need to use the tool tomorrow night, and
would like to bypass the internal variable speed circuitry to simplify
it; maybe buy an external control later.

There aren't any wiring diagrams I could find on theDremelsite. I'm
thinking if I had one for the model 275 tool (single speed) and the
395 (electronic variable speed), I might be able to make the 395 into
a 275 by just jumpering some wires. I'll probaqbly need to at least
retain the variable speed assembly, since the brushes fit into it.


If it runs at all, hopefully at full speed, jst plug it in to a sewing
machine rheostat, Works fine for me.

Boris



[email protected] October 4th 07 06:49 AM

how to bypass dremel tool internal variable speed control?
 
On Sep 11, 5:07 pm, Jerry wrote:
On Sep 10, 12:06 pm, "Michael A. Terrell"
wrote:

BTW, have you seen the small DC powered clone at Harbor Freight? It
runs on 12 VDC, and comes with an AC adapter. I was thinking about
using one (or more, with different sized drills) with a homebrew CNC
machine to drill PC boards.


I have one of those HF pseudo-dremels. Not very torque-y at all. Bogs
down very easily. A very light touch is required.

Jerry


Plus the collets are brass and wear out in no time. Good for a one or
two time use project, no substitute for a pneumatic die grinder.
Bearings suck on them, too. Whadda ya want for $6 anyway? Spend a
couple of bucks more and get the mini-pneumatic die grinder. Some of
the ones I have accept Foredom collets, too.

Stan


James Sweet October 4th 07 08:45 AM

how to bypass dremel tool internal variable speed control?
 

wrote in message
ups.com...
On Sep 11, 5:07 pm, Jerry wrote:
On Sep 10, 12:06 pm, "Michael A. Terrell"
wrote:

BTW, have you seen the small DC powered clone at Harbor Freight? It
runs on 12 VDC, and comes with an AC adapter. I was thinking about
using one (or more, with different sized drills) with a homebrew CNC
machine to drill PC boards.


I have one of those HF pseudo-dremels. Not very torque-y at all. Bogs
down very easily. A very light touch is required.

Jerry


Plus the collets are brass and wear out in no time. Good for a one or
two time use project, no substitute for a pneumatic die grinder.
Bearings suck on them, too. Whadda ya want for $6 anyway? Spend a
couple of bucks more and get the mini-pneumatic die grinder. Some of
the ones I have accept Foredom collets, too.

Stan


Well you need an air compressor for one of those, a tool relatively few
people own. I use a pneumatic die grinder occasionally, but it's louder than
my Dremel and it spews out a bit of oil in use.



Stuart[_2_] October 4th 07 05:40 PM

how to bypass dremel tool internal variable speed control?
 
In article . com,
wrote:
On Sep 11, 5:07 pm, Jerry wrote:
On Sep 10, 12:06 pm, "Michael A. Terrell"
wrote:

BTW, have you seen the small DC powered clone at Harbor Freight? It
runs on 12 VDC, and comes with an AC adapter. I was thinking about
using one (or more, with different sized drills) with a homebrew CNC
machine to drill PC boards.



Sorry not to reply to this directly, I don't seem to have the original.

If you're interested in making PCBs have you looked at the mailing list
" and their archives?

--
Stuart Winsor

From is valid but subject to change without notice if it gets spammed.

For Barn dances and folk evenings in the Coventry and Warwickshire area
See: http://www.barndance.org.uk

Rich Grise October 4th 07 11:53 PM

how to bypass dremel tool internal variable speed control?
 
On Thu, 04 Oct 2007 06:45:49 +0000, James Sweet wrote:
wrote in message
On Sep 11, 5:07 pm, Jerry wrote:
On Sep 10, 12:06 pm, "Michael A. Terrell"

BTW, have you seen the small DC powered clone at Harbor Freight? It
runs on 12 VDC, and comes with an AC adapter. I was thinking about
using one (or more, with different sized drills) with a homebrew CNC
machine to drill PC boards.

I have one of those HF pseudo-dremels. Not very torque-y at all. Bogs
down very easily. A very light touch is required.


Plus the collets are brass and wear out in no time. Good for a one or
two time use project, no substitute for a pneumatic die grinder.
Bearings suck on them, too. Whadda ya want for $6 anyway? Spend a
couple of bucks more and get the mini-pneumatic die grinder. Some of
the ones I have accept Foredom collets, too.


Well you need an air compressor for one of those, a tool relatively few
people own. I use a pneumatic die grinder occasionally, but it's louder than
my Dremel and it spews out a bit of oil in use.


Sounds like you nead an oil trap next to your bench.

Good Luck!
Rich


James Sweet October 5th 07 12:14 AM

how to bypass dremel tool internal variable speed control?
 

Well you need an air compressor for one of those, a tool relatively few
people own. I use a pneumatic die grinder occasionally, but it's louder
than
my Dremel and it spews out a bit of oil in use.


Sounds like you nead an oil trap next to your bench.



Well that would defeat the purpose of the oil in the first place, which is
squirted into the tool to lubricate the air motor. Perhaps you're referring
to the high speed air turbine tools? Either way unless you already have the
compressor as I did, an electric tool is far cheaper and is not tethered to
a big heavy noisy piece of equipment.




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