soft start circuit for angle grinder - anyone done one?

[Des Bromilow]

Hi,

I've got an antique angle grinder which does not have a soft start - as
a result the retainer siezes on and it's a right PITA.

Knowing modern grinders have softstarts built in, is it possible to
retrofit a softstart circuit into an older grinder?
The grinder is single phase 240 VAC and about 2kW. I've sent Makita an
email, but heard nothing back yet.

If it's not something easily built, does anyone know of a module which
can be added in from another model? links to part numbers, cct
schematics etc? All I've found googling are audio ccts - not single
phase power units.

Thanks,
Des

 

[kreed]

On Apr 7, 11:01 pm, Des Bromilow <desbromi...@yahoo.comV2> wrote:

Hi,

I've got an antique angle grinder which does not have a soft start - as
a result the retainer siezes on and it's a right PITA.

Knowing modern grinders have softstarts built in, is it possible to
retrofit a softstart circuit into an older grinder?
The grinder is single phase 240 VAC and about 2kW. I've sent Makita an
email, but heard nothing back yet.

If it's not something easily built, does anyone know of a module which
can be added in from another model? links to part numbers, cct
schematics etc? All I've found googling are audio ccts - not single
phase power units.

Thanks,
Des

I was thinking something along the lines of a light dimmer type
circuit, with a suitably rated triac, turn the knob from zero to full
to turn it on. Or modify it with a resistor/capacitor type
arrangement to simulate turning the knob from zero to full over a
couple of seconds when started. ?

 

[Grant]

On Thu, 07 Apr 2011 21:01:13 +0800, Des Bromilow <desbromilow@yahoo.comV2> wrote:

Hi,

I've got an antique angle grinder which does not have a soft start - as
a result the retainer siezes on and it's a right PITA.

Wimp, just get a good grip on the thing before turning on the power

Yes I know they like to try jumping out of your hands

Solutions? How technical are you?

Series resistor shorted out by a timed relay? Simple but mechanical.

Current surge limit thermistor as used in power supplies? Bad because
they need a long cool-down period after use, or use a timed relay to
short the thermistor during use so it's cool for the next start.

Some sort of TRIAC based slow start? Haven't seen one, but then I
haven't been looking for one either, it's a simple enough problem.

Knowing modern grinders have softstarts built in, is it possible to
retrofit a softstart circuit into an older grinder?

If there's room, otherwise inline.

The grinder is single phase 240 VAC and about 2kW. I've sent Makita an
email, but heard nothing back yet.

Ouch, big enough

If it's not something easily built, does anyone know of a module which
can be added in from another model? links to part numbers, cct
schematics etc? All I've found googling are audio ccts - not single
phase power units.

Start by looking for a drill speed controller, and think of sending a ramp
voltage into whatever the speed wiper goes into, but it depends on the
circuit you start with.

Grant.

 

[Dennis]

"Des Bromilow" <desbromilow@yahoo.comV2> wrote in message
news:4d9db59f$0$11207$c30e37c6@exi-reader.telstra.net...

Hi,

I've got an antique angle grinder which does not have a soft start - as a
result the retainer siezes on and it's a right PITA.

Knowing modern grinders have softstarts built in, is it possible to
retrofit a softstart circuit into an older grinder?
The grinder is single phase 240 VAC and about 2kW. I've sent Makita an
email, but heard nothing back yet.

If it's not something easily built, does anyone know of a module which can
be added in from another model? links to part numbers, cct schematics etc?
All I've found googling are audio ccts - not single phase power units.

Thanks,
Des

Maybe just try some anti-seize on the threads (& retainer face?). Loctite
makes a good anti-seize compound. Lots less work......

 

[F Murtz]

Grant wrote:

On Thu, 07 Apr 2011 21:01:13 +0800, Des Bromilow<desbromilow@yahoo.comV2> wrote:

Hi,

I've got an antique angle grinder which does not have a soft start - as
a result the retainer siezes on and it's a right PITA.

Wimp, just get a good grip on the thing before turning on the power

His complaint is that it tightens the blade to much, getting a grip has
nothing to do with it.

Yes I know they like to try jumping out of your hands

Solutions? How technical are you?

Series resistor shorted out by a timed relay? Simple but mechanical.

Current surge limit thermistor as used in power supplies? Bad because
they need a long cool-down period after use, or use a timed relay to
short the thermistor during use so it's cool for the next start.

Some sort of TRIAC based slow start? Haven't seen one, but then I
haven't been looking for one either, it's a simple enough problem.

Knowing modern grinders have softstarts built in, is it possible to
retrofit a softstart circuit into an older grinder?

If there's room, otherwise inline.

The grinder is single phase 240 VAC and about 2kW. I've sent Makita an
email, but heard nothing back yet.

Ouch, big enough

If it's not something easily built, does anyone know of a module which
can be added in from another model? links to part numbers, cct
schematics etc? All I've found googling are audio ccts - not single
phase power units.

Start by looking for a drill speed controller, and think of sending a ramp
voltage into whatever the speed wiper goes into, but it depends on the
circuit you start with.

Grant.

 

[Graeme Zimmer]

Series resistor shorted out by a timed relay? Simple but mechanical.

This is the classic solution for a soft start. Doesn't even need a timed
relay.
The initial voltage drop causes the relay to delay until the motor comes up
to speed.

.................. Zim

 

[Grant]

On Fri, 08 Apr 2011 14:50:19 +1000, F Murtz <haggisz@hotmail.com> wrote:

Grant wrote:
On Thu, 07 Apr 2011 21:01:13 +0800, Des Bromilow<desbromilow@yahoo.comV2> wrote:

Hi,

I've got an antique angle grinder which does not have a soft start - as
a result the retainer siezes on and it's a right PITA.

Wimp, just get a good grip on the thing before turning on the power


His complaint is that it tightens the blade to much, getting a grip has
nothing to do with it.

learn to spell (s/to/too/)

Grant.

 

[F Murtz]

Grant wrote:

On Fri, 08 Apr 2011 14:50:19 +1000, F Murtz<haggisz@hotmail.com> wrote:

Grant wrote:
On Thu, 07 Apr 2011 21:01:13 +0800, Des Bromilow<desbromilow@yahoo.comV2> wrote:

Hi,

I've got an antique angle grinder which does not have a soft start - as
a result the retainer siezes on and it's a right PITA.

Wimp, just get a good grip on the thing before turning on the power


His complaint is that it tightens the blade to much, getting a grip has
nothing to do with it.

learn to spell (s/to/too/)

Grant.
The extra o just wastes bandwidth just like this post (and your post)

 

[Jasen Betts]

On 2011-04-07, Des Bromilow <desbromilow@yahoo.comV2> wrote:

Hi,

I've got an antique angle grinder which does not have a soft start - as
a result the retainer siezes on and it's a right PITA.

do it up tight before you turn it on.

Knowing modern grinders have softstarts built in, is it possible to
retrofit a softstart circuit into an older grinder?

All the 100mm cheapies I've used had no such thing, I never used
the spanner just gripped the disc and turned it hand tight.
after use it was still hand-tight.

If the disc slips at startup it will overtighten the nut.

The grinder is single phase 240 VAC and about 2kW. I've sent Makita an
email, but heard nothing back yet.

It's a big one then, you've got to get the nut really tight on those,
two-hand tight. You say it's old, perhaps you need to replace the
retainer nut and/or spindle. Does is look worn ?

If it's not something easily built, does anyone know of a module which
can be added in from another model? links to part numbers, cct
schematics etc? All I've found googling are audio ccts - not single
phase power units.

go to makita and grab the spare-parts diagrams, if it's not a feature
of the rotor their replacement part for the new models may fit yours.

⚂⚃ 100% natural

--- news://freenews.netfront.net/ - complaints: news@netfront.net ---

 

[no one]

try this...

http://www.pne.com.au/products/istart.shtml?gclid=CKvn8cnyl6gCFQlspAod62t3Cg

mark



"Des Bromilow" <desbromilow@yahoo.comV2> wrote in message
news:4d9db59f$0$11207$c30e37c6@exi-reader.telstra.net...

Hi,

I've got an antique angle grinder which does not have a soft start - as a
result the retainer siezes on and it's a right PITA.

Knowing modern grinders have softstarts built in, is it possible to
retrofit a softstart circuit into an older grinder?
The grinder is single phase 240 VAC and about 2kW. I've sent Makita an
email, but heard nothing back yet.

If it's not something easily built, does anyone know of a module which can
be added in from another model? links to part numbers, cct schematics etc?
All I've found googling are audio ccts - not single phase power units.

Thanks,
Des

 

On Thursday, April 7, 2011 6:31:13 PM UTC+5:30, Des Bromilow wrote:

Hi,

I've got an antique angle grinder which does not have a soft start - as
a result the retainer siezes on and it's a right PITA.

Knowing modern grinders have softstarts built in, is it possible to
retrofit a softstart circuit into an older grinder?
The grinder is single phase 240 VAC and about 2kW. I've sent Makita an
email, but heard nothing back yet.

If it's not something easily built, does anyone know of a module which
can be added in from another model? links to part numbers, cct
schematics etc? All I've found googling are audio ccts - not single
phase power units.

Thanks,
Des

I have an endico angel grinder which doesn't require this so never tried this before.It is long lasting and durable.

http://www.endicopowertools.com/electric-angle-grinder.php

 

[JW]

On Thu, 5 Sep 2013 04:17:01 -0700 (PDT) karam.brar87@gmail.com wrote in
Message id: <2ecabf74-deae-4ef5-a464-2424473d8370@googlegroups.com>:

On Thursday, April 7, 2011 6:31:13 PM UTC+5:30, Des Bromilow wrote:
Hi,

I've got an antique angle grinder which does not have a soft start - as
a result the retainer siezes on and it's a right PITA.

Knowing modern grinders have softstarts built in, is it possible to
retrofit a softstart circuit into an older grinder?
The grinder is single phase 240 VAC and about 2kW. I've sent Makita an
email, but heard nothing back yet.

If it's not something easily built, does anyone know of a module which
can be added in from another model? links to part numbers, cct
schematics etc? All I've found googling are audio ccts - not single
phase power units.

Thanks,
Des

I have an endico angel grinder which doesn't require this so never tried this before.
It is long lasting and durable.
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

I'll take thing that a spammer would say for $100, Alex.

>http://www.endiSPAM

 

[Bob Milutinovic]

"JW" <none@dev.null> wrote in message
news:mm2h29hpqnpd4r0kcpn5s1p7jbdtgaob9t@4ax.com...

On Thu, 5 Sep 2013 04:17:01 -0700 (PDT) karam.brar87@gmail.com wrote in
Message id: <2ecabf74-deae-4ef5-a464-2424473d8370@googlegroups.com>:

<snip most of the spam>

I have an endico angel grinder which doesn't require this so never tried
this before.
It is long lasting and durable.
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

I'll take thing that a spammer would say for $100, Alex.

http://www.endiSPAM

I wonder how much torque's required to grind an angel?

--
Bob Milutinovic
Cognicom