A polishing disk from a washing machine

And now for something completely different: I dismantled a washing
machine last week with the vague idea of making a polishing disk
from it. Has anybody done this before, and are there any caveats?

The general idea is to throw away the inner and outer drum, but
keep the assemblage on which the drums were mounted. As it is (was!)
a front-loading machine, it is mounted at only one side, with
heavy bearings.

On the bracket for the inner drum, I propose to mount a wooden disk
of 50 cm diameter, and on top of this a glass disk. The bracket,
axle and V-belt wheel are mounted again in a PVC basin, made from
an old 400 litre container.

I have the following worries:

1. what is the maximum speed with which a polishing wheel
normally revolves? I do not know the original speed of
the motor, and I am also uncertain about throttling it down.
It seems condensators come in somewhere...

2. How much horizontal play (vibration) is admissible?
What if the axis is off-center? Would it be a good idea
to mount a rubber mat or so on the wooden disk?

3. What is the best way to prevent the glass disc of
becoming a discus? In a professional shop I have seen a
polishing wheel with only 80 revs/minute, and there
the glass disk just was put on the wooden disk, without
brackets or adhesive. It feels a bit unsafe, even with the
PVC rim around the installation.

Suggestions are welcome. I promise not to mention the L-word.

You could also look here for an idea

http://www.ceramicsmonthly.org/mustreads/wheel.asp

and rec.crafts.metalworking is always active and helpful.
I haven't heard of a conversion like this but it sounds doable. I added a 150mm grinder surface to my Krystal 2000 glass grinder. I used UHDPE sheet with self adhesive diamond sheet for the grinding surface. The UHDPE discs are interchangeable so I can use different grades. I shall add this to my web site i'm working on and send you the link soon.

1. I don't know what the speed would be but at a guess from one I have seen converted from a plane blade sharpener at LGC, 150 - 200 RPM and its disc is about 50cm diameter. Is the washing machine a modern variable speed?. Does the motor use brushes.

2. The less the better but you are going to run it fairly slowly so if accurately made I wouldn't expect much problem. Rubber would help keep the glass and wood together in my experience as the glass is less likely to slip on the rubber.

3. Add a ring around the wooden disc to stop it going anywhere.


Hans Paijmans wrote:


And now for something completely different: I dismantled a washing
machine last week with the vague idea of making a polishing disk
from it. Has anybody done this before, and are there any caveats?

The general idea is to throw away the inner and outer drum, but
keep the assemblage on which the drums were mounted. As it is (was!)
a front-loading machine, it is mounted at only one side, with
heavy bearings.

On the bracket for the inner drum, I propose to mount a wooden disk
of 50 cm diameter, and on top of this a glass disk. The bracket,
axle and V-belt wheel are mounted again in a PVC basin, made from
an old 400 litre container.

I have the following worries:

1. what is the maximum speed with which a polishing wheel
normally revolves? I do not know the original speed of
the motor, and I am also uncertain about throttling it down.
It seems condensators come in somewhere...

2. How much horizontal play (vibration) is admissible?
What if the axis is off-center? Would it be a good idea
to mount a rubber mat or so on the wooden disk?

3. What is the best way to prevent the glass disc of
becoming a discus? In a professional shop I have seen a
polishing wheel with only 80 revs/minute, and there
the glass disk just was put on the wooden disk, without
brackets or adhesive. It feels a bit unsafe, even with the
PVC rim around the installation.

Suggestions are welcome. I promise not to mention the L-word.

David Billington wrote:
You could also look here for an idea

http://www.ceramicsmonthly.org/mustreads/wheel.asp

and rec.crafts.metalworking is always active and helpful.

So is our dutch electronics community.

1. I don't know what the speed would be but at a guess from one I have
seen converted from a plane blade sharpener at LGC, 150 - 200 RPM and
its disc is about 50cm diameter. Is the washing machine a modern
variable speed?. Does the motor use brushes.

It is a 15 year old Miele, so far as I can see without brushes,
but with a really *big* pack of condensators. I have the vague
idea that the speed of such motors can be varied by adding
condensators, but I must go back to nl.hobby.electronica to
get a clear answer.

If I can get the thing working, I will publish photos and
experiences on my site, if not - you will read it in my
obiutary... obutary... obituio... IN MEMORIAM!

paai

"Hans Paijmans" wrote in message
...

And now for something completely different: I dismantled a washing
machine last week with the vague idea of making a polishing disk
from it. Has anybody done this before, and are there any caveats?

The general idea is to throw away the inner and outer drum, but
keep the assemblage on which the drums were mounted. As it is (was!)
a front-loading machine, it is mounted at only one side, with
heavy bearings.

On the bracket for the inner drum, I propose to mount a wooden disk
of 50 cm diameter, and on top of this a glass disk. The bracket,
axle and V-belt wheel are mounted again in a PVC basin, made from
an old 400 litre container.

I have the following worries:

1. what is the maximum speed with which a polishing wheel
normally revolves? I do not know the original speed of
the motor, and I am also uncertain about throttling it down.
It seems condensators come in somewhere...

2. How much horizontal play (vibration) is admissible?
What if the axis is off-center? Would it be a good idea
to mount a rubber mat or so on the wooden disk?

3. What is the best way to prevent the glass disc of
becoming a discus? In a professional shop I have seen a
polishing wheel with only 80 revs/minute, and there
the glass disk just was put on the wooden disk, without
brackets or adhesive. It feels a bit unsafe, even with the
PVC rim around the installation.

Suggestions are welcome. I promise not to mention the L-word.


Proposals to help.
Could use more help in seeing this,
So you are mounting this on the end of a horizontal arbor?
Any chance or small sketch and a link to it?

1) Reducing the speed at the arbor, wooden disk? (What is the glass disk
for?) could be accomplished with different size pulleys. On the polishing
arbor on my beveller is a 14" pulley, never measured, just guessing, with a
3" pulley on the motor. My wheel runs about 90 RPM, or slower.

2)The less play, as in none, will give the best and truest surface, from
there it is what you can put up with.

3)Haven't figured out the use of the glass disk? Is it to hold grit?

Check out this link, may save you some grief, and have some apps you can
make use of.
http://www.hisglassworks.com/files/lapplans.pdf

Javahut wrote:

Proposals to help.
Could use more help in seeing this,
So you are mounting this on the end of a horizontal arbor?
Any chance or small sketch and a link to it?

1) Reducing the speed at the arbor, wooden disk? (What is the glass disk
for?) could be accomplished with different size pulleys. On the polishing
arbor on my beveller is a 14" pulley, never measured, just guessing, with a
3" pulley on the motor. My wheel runs about 90 RPM, or slower.

2)The less play, as in none, will give the best and truest surface, from
there it is what you can put up with.

3)Haven't figured out the use of the glass disk? Is it to hold grit?

Check out this link, may save you some grief, and have some apps you can
make use of.
http://www.hisglassworks.com/files/lapplans.pdf


This pdf-file for some reason gives solid black squares
where pictures should be. Of course I use, um, a different
operating system, but I never seen this problem.

Anyway, I lay the bracket (arbor???) on its back, so the
wheel wil turn in the horizontal plane. I am taking
photos with my digital camera, so it should become
clear when I put them on the web.

On the first test it shook rather badly, but then I put the
blocks of cast iron that served as contraweights in the
original washingmachine on the rim, and then it was more
or less rock-solid. Now I have to do some shopping, and
tonight I'll mount the wooden disk. Things look promising.

The glass disk is to put carborundum slush on.


Paai

If its variable speed which I expect it is then it will probably have
brushes. I am not aware of motors which use capacitors to vary speed but
more info may be required. Photo posted somewhere might make it clearer.



Hans Paijmans wrote:

David Billington wrote:

You could also look here for an idea

http://www.ceramicsmonthly.org/mustreads/wheel.asp

and rec.crafts.metalworking is always active and helpful.


So is our dutch electronics community.

1. I don't know what the speed would be but at a guess from one I
have seen converted from a plane blade sharpener at LGC, 150 - 200
RPM and its disc is about 50cm diameter. Is the washing machine a
modern variable speed?. Does the motor use brushes.


It is a 15 year old Miele, so far as I can see without brushes,
but with a really *big* pack of condensators. I have the vague
idea that the speed of such motors can be varied by adding
condensators, but I must go back to nl.hobby.electronica to
get a clear answer.

If I can get the thing working, I will publish photos and
experiences on my site, if not - you will read it in my
obiutary... obutary... obituio... IN MEMORIAM!

paai

I too use linux and currently Mandrake 8.2 and mozilla 0.9.8 and the PDF
views fine with the plugin so may just be an issue with your setup.

Hans Paijmans wrote:

Javahut wrote:

Proposals to help.
Could use more help in seeing this,
So you are mounting this on the end of a horizontal arbor?
Any chance or small sketch and a link to it?

1) Reducing the speed at the arbor, wooden disk? (What is the glass disk
for?) could be accomplished with different size pulleys. On the
polishing
arbor on my beveller is a 14" pulley, never measured, just guessing,
with a
3" pulley on the motor. My wheel runs about 90 RPM, or slower.

2)The less play, as in none, will give the best and truest surface, from
there it is what you can put up with.

3)Haven't figured out the use of the glass disk? Is it to hold grit?

Check out this link, may save you some grief, and have some apps you can
make use of.
http://www.hisglassworks.com/files/lapplans.pdf



This pdf-file for some reason gives solid black squares
where pictures should be. Of course I use, um, a different
operating system, but I never seen this problem.

Anyway, I lay the bracket (arbor???) on its back, so the
wheel wil turn in the horizontal plane. I am taking
photos with my digital camera, so it should become
clear when I put them on the web.

On the first test it shook rather badly, but then I put the
blocks of cast iron that served as contraweights in the
original washingmachine on the rim, and then it was more
or less rock-solid. Now I have to do some shopping, and
tonight I'll mount the wooden disk. Things look promising.

The glass disk is to put carborundum slush on.


Paai

On Fri, 06 Feb 2004 15:12:05 GMT, Hans Paijmans wrote:

http://www.hisglassworks.com/files/lapplans.pdf


This pdf-file for some reason gives solid black squares
where pictures should be. Of course I use, um, a different
operating system, but I never seen this problem.

Works fine here... both xpdf-0.92-1.62.0 and
Acrobat4, so it's definitely not your OS.

As I understand it, condensors are for short term
current "storage" to supply that large current draw
when the motor first starts. I've never heard of them
having anything to do with motor speed.

--
Steve Ackman
http://twoloonscoffee.com (Need green beans?)
http://twovoyagers.com (glass, linux & other stuff)

"Steve Ackman" wrote in message
...
On Fri, 06 Feb 2004 15:12:05 GMT, Hans Paijmans
wrote:

As I understand it, condensors are for short term
current "storage" to supply that large current draw
when the motor first starts. I've never heard of them
having anything to do with motor speed.

That's because condensors have nothing to do with motor speed. Varying
voltage causes the motor to slow/speedup. Condensers only "store" voltage,
not modulate it.

I'm no motor expert, but it seems to me that most, if not all, of the
variable speed motors I've seen/used were DC voltage. Washing machines vary
the speed of the tub by a gearbox which is activated by a solenoid. Some AC
motors have two sets of windings in them, and the motor RPM varys by which
set of windings are selected. Like a furnace fan, for example.

My 10 year old+ Servis 1100 washing machine has a brushed motor just
like a variable speed drill and poly V belt drive giving about 20:1
reduction. It is capable of running down to maybe 60 rpm and upto
1100rpm. No gearbox required. Variable speed AC brushed motors are
common these days and have been for some time like electric drills etc.
What I don't know is if they would use phase angle control (like a light
dimmer) or PWM control. For simple items such as drills phase angle is
common as its simple and cheap. If a bank of capacitors is present it
may be there to smooth the power supply to the motor. It may be DC as
you suggest and a switching power supply design utilised and the
capacitors are used to smooth the supply to the motor.

Moonraker wrote:

"Steve Ackman" wrote in message
...

On Fri, 06 Feb 2004 15:12:05 GMT, Hans Paijmans

wrote:

As I understand it, condensors are for short term
current "storage" to supply that large current draw
when the motor first starts. I've never heard of them
having anything to do with motor speed.


That's because condensors have nothing to do with motor speed. Varying
voltage causes the motor to slow/speedup. Condensers only "store" voltage,
not modulate it.

I'm no motor expert, but it seems to me that most, if not all, of the
variable speed motors I've seen/used were DC voltage. Washing machines vary
the speed of the tub by a gearbox which is activated by a solenoid. Some AC
motors have two sets of windings in them, and the motor RPM varys by which
set of windings are selected. Like a furnace fan, for example.