Car mirror heater pad

[Dave Plowman (News)]

I've done a fair bit of research in the UK and come up with nothing, so
cast myself humbly on the mercy of this group. ;-)

I've got an old car which has heated door mirrors. Both the elements are
burnt out, and spares are no longer available. The mirrors themselves (the
heating was an option) are no problem. So what I'd like to buy are
suitable heating mats to replace the originals. RS Components do silicone
heating mats for 12 volts, but not in a suitable size which is approx 100
x 50mm. The thickness should be not much more than about 1 mm.
The originals appeared rather like a PCB made of thin flexible plastic
with silver coloured tracks as the heating element.

I can make copper PCBs at home using conventional methods, and of course a
similar method using this plastic material would be great. If I knew what
it was and where to get it.

I'd also be willing to pay for a small production run of say 100 if the
price was right as other owners are in the same position and winter's
coming on...

 

[Homer J Simpson]

The originals appeared rather like a PCB made of thin flexible plastic
with silver coloured tracks as the heating element.

Is there room to fit a light bulb or two? You could run two in series for
heat without much light.

Another way would be to buy a 240 Volt radiator element and some fibreglass
tubing and make up a 12 volt heater that way. Cut the wire off the radiator
element - 1/12 of the heater rod would be too little so use double that
perhaps.

 

[Jim Yanik]

I've done a fair bit of research in the UK and come up with nothing,
so cast myself humbly on the mercy of this group. ;-)

I've got an old car which has heated door mirrors. Both the elements
are burnt out, and spares are no longer available. The mirrors
themselves (the heating was an option) are no problem. So what I'd
like to buy are suitable heating mats to replace the originals. RS
Components do silicone heating mats for 12 volts, but not in a
suitable size which is approx 100 x 50mm. The thickness should be not
much more than about 1 mm. The originals appeared rather like a PCB
made of thin flexible plastic with silver coloured tracks as the
heating element.

I can make copper PCBs at home using conventional methods, and of
course a similar method using this plastic material would be great. If
I knew what it was and where to get it.

I'd also be willing to pay for a small production run of say 100 if
the price was right as other owners are in the same position and
winter's coming on...

Get some plastic sheet,and some resistive ink(GC silver print?),and make
your own.
(perhaps laminating the sheet in plastic would increase durability?)

Use riveted terminals to attach the heater to the car's wiring.
If you had a flat-bad plotter,you could use that to write the ink onto the
plastic,especially for a production run.

 

[James Thompson]

I've done a fair bit of research in the UK and come up with nothing, so
cast myself humbly on the mercy of this group. ;-)

I've got an old car which has heated door mirrors. Both the elements are
burnt out, and spares are no longer available. The mirrors themselves (the
heating was an option) are no problem. So what I'd like to buy are
suitable heating mats to replace the originals. RS Components do silicone
heating mats for 12 volts, but not in a suitable size which is approx 100
x 50mm. The thickness should be not much more than about 1 mm.
The originals appeared rather like a PCB made of thin flexible plastic
with silver coloured tracks as the heating element.

I can make copper PCBs at home using conventional methods, and of course a
similar method using this plastic material would be great. If I knew what
it was and where to get it.

I'd also be willing to pay for a small production run of say 100 if the
price was right as other owners are in the same position and winter's
coming on...

--
*In some places, C:\ is the root of all directories *

Dave Plowman [email protected] London SW
To e-mail, change noise into sound.

For a DIY project: take a small plastic sheet that will fit the back of the
mirror and get some enameled wire (magnet wire). lay out a coil on the
plastic and glue it down to the sheet. That is your heater, and to control
the temperature of it - make a constant current source using an LM317T
regulator. The data sheet will show how to do it. JTT

 

[lakewood]

I've done a fair bit of research in the UK and come up with nothing, so
cast myself humbly on the mercy of this group. ;-)

I've got an old car which has heated door mirrors. Both the elements are
burnt out, and spares are no longer available. The mirrors themselves (the
heating was an option) are no problem. So what I'd like to buy are
suitable heating mats to replace the originals. RS Components do silicone
heating mats for 12 volts, but not in a suitable size which is approx 100
x 50mm. The thickness should be not much more than about 1 mm.
The originals appeared rather like a PCB made of thin flexible plastic
with silver coloured tracks as the heating element.

I can make copper PCBs at home using conventional methods, and of course a
similar method using this plastic material would be great. If I knew what
it was and where to get it.

I'd also be willing to pay for a small production run of say 100 if the
price was right as other owners are in the same position and winter's
coming on...

--
*In some places, C:\ is the root of all directories *

Dave Plowman [email protected] London SW
To e-mail, change noise into sound.

 

[Tony Marsillo]

I've done a fair bit of research in the UK and come up with nothing, so
cast myself humbly on the mercy of this group. ;-)

I've got an old car which has heated door mirrors. Both the elements are
burnt out, and spares are no longer available. The mirrors themselves (the
heating was an option) are no problem. So what I'd like to buy are
suitable heating mats to replace the originals. RS Components do silicone
heating mats for 12 volts, but not in a suitable size which is approx 100
x 50mm. The thickness should be not much more than about 1 mm.
The originals appeared rather like a PCB made of thin flexible plastic
with silver coloured tracks as the heating element.

I can make copper PCBs at home using conventional methods, and of course a
similar method using this plastic material would be great. If I knew what
it was and where to get it.

I'd also be willing to pay for a small production run of say 100 if the
price was right as other owners are in the same position and winter's
coming on...

--
*In some places, C:\ is the root of all directories *

Dave Plowman [email protected] London SW
To e-mail, change noise into sound.

If you took a few power resistors and epoxyed them to the back of the mirror
that might work. I don't think they would need to disipate much to melt ice
in the winter.

Tony

 

[Dave Plowman (News)]

If you took a few power resistors and epoxyed them to the back of the
mirror that might work. I don't think they would need to disipate much
to melt ice in the winter.

Space is a problem. The glass is glued to a thin frame which clips onto
the motor assembly. There is some space in the centre of the mirror, but
some form of thin heating mat as original would be best.

 

[Homer J Simpson]

Space is a problem. The glass is glued to a thin frame which clips onto
the motor assembly. There is some space in the centre of the mirror, but
some form of thin heating mat as original would be best.

Then use the 240 Volt radiator element and some fibreglass tubing and make
up a 12 volt heater that way.

Unless a wrecker has these your chances look pretty slim. I doubt that
cutting down the RS Components pads will work.

 

[Ken Weitzel]

Then use the 240 Volt radiator element and some fibreglass tubing and make
up a 12 volt heater that way.

Unless a wrecker has these your chances look pretty slim. I doubt that
cutting down the RS Components pads will work.

Hi...

Just a thought, but how's about straightening out as best you
can a piece of nichrome from an old toaster and zig zag an appropriate
length behind the mirror?

Take care.

Ken

 

[Homer J Simpson]

Just a thought, but how's about straightening out as best you
can a piece of nichrome from an old toaster and zig zag an appropriate
length behind the mirror?

Same idea. Just use the fibreglass tubing to prevent shorts.

 

[Dave Plowman (News)]

Then use the 240 Volt radiator element and some fibreglass tubing and
make up a 12 volt heater that way.

That's another thought. My idea for using NiChrome resistance wire was to
weave it through some thin flexible sheet - but don't know what sort of
sheet would stand the temperature. First thoughts were mica.

Unless a wrecker has these your chances look pretty slim.

Thing is I believe it's still the way heated mirrors are made so someone
must still make the elements. The size isn't critical as the original only
covers about 1/2 of the area.

As regards secondhand ones, the stupid wiring has the element on all the
time the car is running, and the youngest cars are now 20 years old. When
I do find a solution I'll think of a better way. Either switched by the
heated rear screen circuit, or incorporate a thermostat.

I doubt that cutting down the RS Components pads will work.

My feeling is also that their heat output per area is too small for this
app.

 

[Homer J Simpson]

My feeling is also that their heat output per area is too small for this
app.

My guess is that cutting one will kill it.

 

[Lionel]

Space is a problem. The glass is glued to a thin frame which clips onto
the motor assembly. There is some space in the centre of the mirror, but
some form of thin heating mat as original would be best.

Surface mount resistors make good, flat heating elements. (I've seen
them used that way in one of those mains-powered slow release air
freshener gizmos.)

PS: Whatever method you use, don't forget that the silver coating on
the mirror is conductive, & most mirrors only only have a thin coat of
paint protecting it, so you'll need to insulate anything powered that
presses agains the mirrors.