Rear Window Defroster

[Thanatopsis]

I've been working on the design of a wiring harness to keep myself busy with coupe related projects while I save my pennies. I plan on it being a daily driver so I want climate control and the like which leads to my question. Has anyone installed or considered a rear window defogger/defroster in a coupe?

I found this on the intarwebs: Frost Fighter 2600 Clear View Defrosters

[pefflyem]

Looks like a good idea if you have the glass rear hatch.
The only problem I see is the rear hatch on the coupe is less than the Minimum Width of 40". In the FAQ section they say they are working on a version for a smaller width. Let us know what you find out.
Ed

[trichardson]

I don't have a window in front of me but I imagine you could turn the element sideways and make it fit.

[1cobra]

Hi,
If you plan on driving in cold weather then a 2nd set of tires and rims would be worth it as performance summer tires to not work in cold weather and it is easy to go off roading, and yes I have had my roadster in the snow a couple of times.
Perry.

[tirod]

Exactly the kind of stuff that makes the car a real daily driver, not a garage queen. Reading the link I saw the grid could be mounted sideways, It would fit the biggest part of the flat area.

As for special "winter" tires and rims, I think it's more like, special "summer track" tires. If you drive in the rain, dry tires won't help, especially in July or August downpours. It's pretty indicative of the mindset that surrounds these cars, anything that might be a reasonable choice for a daily driver is considered low speed high drag. Well, not when it's actually used every day.

Choose tires that work in the rain and you get to drive it year round, like we did the muscle cars of the '60's. It's all we had. You drove them or missed a day of work.

[Thanatopsis]

Originally Posted by pefflyem

Looks like a good idea if you have the glass rear hatch... Let us know what you find out.
Ed

I've swapped a couple emails with John over there and he says they can come up with a defogger that will work if I send him the dimensions of the window.

Anybody with a glass hatch and some spare time want to measure the glass as shown in the attachment?

[CJBergquist]

I got 44" across the top, 34" across the bottom and 36.5" from bottom to the wide spot on the top (which is how your diagram looks to me) overall top to bottom is 40.5". There is a 1" black boarder all the way around the glass.

[Thanatopsis]

Thanks Chris. I sent them the info so we'll see what they come up with. With the height of the window being what it is I'm a little concerned with what the power consumption might be.

[Spaceclam]

THe reason they give a maximum and minimum is that it's a resistive heater, where the power busses run up the side. Too wide, and you have too much resistance, and it never gets warm. Too narrow, and it will get very warm and either draw too much current, or damage something.

The window being tall increases the number of wires in paralell, increasing current draw.

So our issue is that the window is too narrow (wires draw too much current, gets too hot and probably melts the self adhesive tape) and the window is too tall (too may wires drawing current) leading to excessive current draw from the unit.

You may very well find that you are just fine if you add some series resistance to the circuit. Or, if you installed the grids in an arc instead of a line, it will cause the arclength of the grid to be longer than the straight line distance from one side to the other. IT will also increase the amount of wire in contact with the glass, causing it to work more efficiently.

Also, you don't need grid lines going all the way down to the bottom, because you can not see out of the bottom of the glass. There's a spoiler in the way.

No reason you couldn't turn the unit sideways and have the copper strips run vertically, and have the bus bars hidden under the smoked edges of the glass.

-Clam