Just as an update having seen some different makes, it appears some are
made out of copper clad Kapton, which is a thin flexible plastic sheet,
suitable for high temperatures, made by DuPont. The copper cladding is
etched into the element - rather like a PCB - and then laminated with a
second layer of plain Kapton. This sounds like it would be suitable for a
small production run - I know of several others who'd like replacement
elements. I've found a couple of suppliers of this stuff in the UK but not
had any replies to my e-mails.

Anyone have details of this process and suggestions for a supplier?

--
*When the going gets tough, the tough take a coffee break *

Dave Plowman London SW
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Dave Plowman (News) wrote:
Just as an update having seen some different makes, it appears some are
made out of copper clad Kapton, which is a thin flexible plastic sheet,
suitable for high temperatures, made by DuPont. The copper cladding is
etched into the element - rather like a PCB - and then laminated with a
second layer of plain Kapton. This sounds like it would be suitable for a
small production run - I know of several others who'd like replacement
elements. I've found a couple of suppliers of this stuff in the UK but not
had any replies to my e-mails.

If there is sufficient space withing the mirror housing, mount a
couple of 12v bulbs in there. You will probably need to paint the bulbs
to prevent the light coming around the edge of the miorror glass.

harry

In article .com,
Mr Harry wrote:
If there is sufficient space withing the mirror housing, mount a
couple of 12v bulbs in there. You will probably need to paint the bulbs
to prevent the light coming around the edge of the miorror glass.

What you need for efficient demisting, etc, is a good even heating source
since glass is a very poor conductor. And bulbs don't provide this.

--
*It doesn't take a genius to spot a goat in a flock of sheep *

Dave Plowman London SW
To e-mail, change noise into sound.

In article ,
"Dave Plowman (News)" writes:
In article .com,
Mr Harry wrote:
If there is sufficient space withing the mirror housing, mount a
couple of 12v bulbs in there. You will probably need to paint the bulbs
to prevent the light coming around the edge of the miorror glass.

What you need for efficient demisting, etc, is a good even heating source
since glass is a very poor conductor. And bulbs don't provide this.

Glueing 10 or so resistors on the back of the mirror would be
good enough.

--
Andrew Gabriel

Dave Plowman (News) wrote:
In article .com,
Mr Harry wrote:
If there is sufficient space withing the mirror housing, mount a
couple of 12v bulbs in there. You will probably need to paint the bulbs
to prevent the light coming around the edge of the miorror glass.

What you need for efficient demisting, etc, is a good even heating source
since glass is a very poor conductor. And bulbs don't provide this.

It certainly de-ices them

harry

In article ,
Andrew Gabriel wrote:
What you need for efficient demisting, etc, is a good even heating
source since glass is a very poor conductor. And bulbs don't provide
this.

Glueing 10 or so resistors on the back of the mirror would be
good enough.

Not enough room. The mirror is glued to a back plate which has a cutout
for the heating element and that cutout is only about 1mm deep. There
would be room for resistance wire, but making such a thing doesn't appear
easy. While etching a PCB type will be - if I can find a source of the
material I've mentioned.

--
*A fool and his money are soon partying *

Dave Plowman London SW
To e-mail, change noise into sound.

In article ,
Dave Plowman (News) wrote:

Not enough room. The mirror is glued to a back plate which has a
cutout for the heating element and that cutout is only about 1mm
deep. There would be room for resistance wire, but making such a
thing doesn't appear easy. While etching a PCB type will be - if
I can find a source of the material I've mentioned.

Sounds like a bit of a no-hoper Dave. All the cars
I've had recently have heated the wing mirrors by
piping some of the warm air from the passenger
compartment vents, through the door, and out behind
the mirror. Would that be an easier mod?

--
Tony Williams.

In article ,
Tony Williams wrote:
Not enough room. The mirror is glued to a back plate which has a
cutout for the heating element and that cutout is only about 1mm
deep. There would be room for resistance wire, but making such a
thing doesn't appear easy. While etching a PCB type will be - if
I can find a source of the material I've mentioned.

Sounds like a bit of a no-hoper Dave. All the cars
I've had recently have heated the wing mirrors by
piping some of the warm air from the passenger
compartment vents, through the door, and out behind
the mirror. Would that be an easier mod?

Interesting. Difficult to do on this car as the mirror is mounted on the
window frame so not much space for an air tube of an adequate size -
although it does have air ducted into the doors for side window demisting.

I've had a quote from a US firm to make the required elements in silicone.

They'd cost 6.30 gbp each - but with a one off tooling charge of 250 gbp.

--
*Beware - animal lover - brakes for pussy*

Dave Plowman London SW
To e-mail, change noise into sound.

Dave Plowman (News) wrote:
Just as an update having seen some different makes, it appears some are
made out of copper clad Kapton, which is a thin flexible plastic sheet,
suitable for high temperatures, made by DuPont. The copper cladding is
etched into the element - rather like a PCB - and then laminated with a
second layer of plain Kapton. This sounds like it would be suitable for a
small production run - I know of several others who'd like replacement
elements. I've found a couple of suppliers of this stuff in the UK but not
had any replies to my e-mails.

Anyone have details of this process and suggestions for a supplier?

I've used these guys in a professional capacity:
http://www.minco.com/
They do a range of off-the-shelf heaters but also custom to you design
- size, resistance etc.

Basicly the process is as you describe. Etched resistive material (not
exaclty sure what) sandwiched between two layers of Kapton.

I found them helpful, flexible and relatively cheap. (I needed 10,000)
but my application was much smaller and higher precision than yours.

Regards,
Jon.

Dave Plowman (News) wrote:

I know of several others who'd like replacement elements.

Why not just buy replacement glass, with a heater element already on it
?

In article . com,
Tournifreak wrote:
Anyone have details of this process and suggestions for a supplier?

I've used these guys in a professional capacity:
http://www.minco.com/
They do a range of off-the-shelf heaters but also custom to you design
- size, resistance etc.

Basicly the process is as you describe. Etched resistive material (not
exaclty sure what) sandwiched between two layers of Kapton.

I found them helpful, flexible and relatively cheap. (I needed 10,000)
but my application was much smaller and higher precision than yours.

Just what I needed. Thanks, Jon.

--
*Why do we say something is out of whack? What is a whack? *

Dave Plowman London SW
To e-mail, change noise into sound.

In article .com,
wrote:
I know of several others who'd like replacement elements.

Why not just buy replacement glass, with a heater element already on it

I suppose you've not seen the whole thread. It's for an older car, and new
heated replacements aren't available anymore. Un-heated ones are, though,
and are identical apart from the heating element. So it would be simply a
matter of removing the mounting frame which is held in place with double
sided tape, inserting the element, and glueing back together.

--
*Why isn't there mouse-flavoured cat food?

Dave Plowman London SW
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Dave Plowman (News) wrote:

It's for an older car, and new heated replacements aren't available anymore.

So bodge it. Find something else that's practically the right size.

Failing that, buy a big one and grind it down.

In article om,
wrote:
It's for an older car, and new heated replacements aren't available
anymore.

So bodge it. Find something else that's practically the right size.

Failing that, buy a big one and grind it down.

That's a possibility that occurred to me since BMW E39 ones are only
slightly oversize - and incorporate a 'blind spot' section. However,
they're of the order of 40 quid each.

--
*I couldn't repair your brakes, so I made your horn louder *

Dave Plowman London SW
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