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Any Experience With Frost Fighter Stick-on Window Defrost Kits?

The kit looks pretty straight forward. The original grid lines appear to be in the glass as a template for the exterior wires. I would add the wires one by one following the grid. I think 83 had the green defrost switch? It was just on/off. I think later switches had a built in or connected timer to the rocker switch, so the defroster would shut off after time/heat (I not sure which). So I think if you purchased a 15 wire and only used 13 wires it wouldn't be a problem with the later switch. Also I would think once your glass is defrosted enough to see you would turn off the grid.
 
I would install them one line at a time following OE grid. First do all 13 original then decide where you would put the last 2. One high and one low? Or both in the center so the window clears up faster?
 
I would install them one line at a time following OE grid. First do all 13 original then decide where you would put the last 2. One high and one low? Or both in the center so the window clears up faster?
Thanks. I am leaning this way too. Doing some computations and trying how best to cut the 4-wire sheets. This is a 12 wire kit so no need to "freehand" any of them. Whew!
 
Just back from measuring my existing grid wire spacing much more carefully. Using a caliper, it is easy to see that the lines in the original grid are NOT consistently spaced. I find some are the same spacing between adjacent wires all the way across the window and others spaced wider in the window's middle than at the edges. And I have found differing widths even measured only at the center. It is interesting that I find similar in my wife's 1980 244.

I am not at all sure how I can adapt to this and keep even single lines applied at a time directly over the existing lines. Hmmm.
 
Just back from measuring my existing grid wire spacing much more carefully. Using a caliper, it is easy to see that the lines in the original grid are NOT consistently spaced. I find some are the same spacing between adjacent wires all the way across the window and others spaced wider in the window's middle than at the edges. And I have found differing widths even measured only at the center. It is interesting that I find similar in my wife's 1980 244.

I am not at all sure how I can adapt to this and keep even single lines applied at a time directly over the existing lines. Hmmm.

How much is the difference? mm? cm?

Sounds like the common issue people encounter when doing restorations... factory work was less precise than expected!
 
I am not at all sure how I can adapt to this and keep even single lines applied at a time directly over the existing lines.

So, the new lines are perfectly straight, because they're attached to some backing paper which won't bend without wrinkling? Hmmm. Cut reliefs in the paper edges, maybe?
 
So, the new lines are perfectly straight, because they're attached to some backing paper which won't bend without wrinkling? Hmmm. Cut reliefs in the paper edges, maybe?
Precisely. But I plan to try anyhow. Waiting now for 60 degree weather here in the PNW. Perhaps this coming week. Cheers
 
How much is the difference? mm? cm?

Sounds like the common issue people encounter when doing restorations... factory work was less precise than expected!

Just saw this. Sorry. Up to 5 mm in some places. Mostly 2-3 mm. And sometimes very little deviations.

I am surprised by these lines in the first place. No idea if they were put in the glass originally or created somehow over the years by using the defroster itself. But either way, I AM surprised at the lack of precision/consistency from the factory - as you mention.
 
The weather is finally warming up here in the PNW. And I have just committed myself to the line-by-line installation. As I am a total newbie at this, I fear what might happen. I also have "tested" to see if I can "see" enough of the lines in the glass through the release paper to follow them in placing the new wires. In short, the answer is NOT REALLY. So I have ordered some 1/8" blue masking tape and I will use that on the outside over the lines so I can see what I am doing more clearly. I can only hope that is enough.
 
One down side of the kit I purchased to achieve 12 wires (closest I could get to the original 13) is that both power and ground tabs on the new grid will be on the driver's side. This makes using the original ground connection on the right side difficult. It could be done using a long wire but... So I went searching for an alternate source of ground for the new grid. Ground is ground, right? While prepping for the install, I removed the plastic covers from the rear seat belt retractors and found the big, honking bolt used to fasten them to the body metal. I tested the bolt head's continuity to the original ground connection and found it solid. So I decided to use that bolt with its nut welded to the underside of the rear deck metal.

I originally thought to solder a wire to a steel washer placed under this bolt head. But I had no luck whatsoever in soldering a copper wire to a large steel washer (tried to solder to a drain plug washer - which I thought was copper - and had no luck there either). No idea why but it has been suggested that I would need a larger iron than I have available. So I am basically giving up on solder joints.

One of the wires in the wire kit I purchased along with the stick-on kit came with a nice, crimped on male spade connector attached and is about 10" long - plenty to route around the plastic cover and plug into the lower tab on the grid. So I decided to sandwich that spade connector between two washers under that large bolt head on the seat belt retractor. I again tested continuity to the original ground connection and found it solid.
 
Nice and warm now in the PNW for a change. Should stay this way a while. So I am plunging onward into the install.

I realized that the original lines in the glass were not going to be visible enough through the kit's release paper to allow me to follow them very well (if at all). So today I applied some 1/8 masking tape over the lines and to demarcate the center and edge lines. Here is the result from outside and in. This shows the difference in visibility. Note: I am not using this topmost line as the kit has only 12 wires compared to the original's 13.

While sitting around and re-reading the instructions (for maybe the 20th time) today, I realized that I missed the admonition on page 6 of 12 to NOT TOUCH THE BUSS BAR METAL! Well too damn late for this dummkoph! While I was working on the layout on paper, realizing that as I am not following the kit's spacing of 1.25" between lines, I was going to have to cut/modify the lengths of the buss bar metal and other components. In doing this, I made full-size drawings and handled the metal quite a bit. Not sure what I can do about that. I have emailed to find out. Damn!
 
Basically spent from 10 am until 3:30 pm (with only minor breaks now and then) struggling with the install of the wire grid from the stick-on kit. I have not completed the connection to power/ground and, of course, have not tested anything yet.

First, the summary conclusions:

1. DO NOT, I repeat, DO NOT try to install the grid lines individually - especially if the window glass is curved as it is on my 240s. I tried everything in my power to get the new wires to follow the old ones in the glass. This is simply impossible to achieve since the new grid wires cannot really be made to follow the way the original lines travel (discussed above). My results are less than ideal and in some places down right awful.

2. There isn't single step in the process that is forgiving. You basically get one chance and one chance only to do something and you must be spot on the very first time. I went slowly - measured twice and cut once and all that. But still managed to get caught off-guard at some points.

3. Baby its hot inside! The instructions insist that you have many hours of 60 degree+ weather to do the install. I would say we hit 70 today but it was only 62-3 when I started. Working in the rear seat, close quarters and all got quite hot - even after I threw a white towel over the window to reduce both heat and glare.

4. Oh my aching knees and back! Good thing I removed the right side front seat from my 242 as I must have had to get in and out of the car about 100 times while doing this. My rear seat has gotten more use today than in the last 20 years for sure. And despite the padding of that seat, it still is quite unpleasant on the old knees. That padding is made for our hindquarters, not our knees.

5. Would I do this again (even if it does work - and I have my doubts)? I certainly don't think so. Installing via the multi-line sheets MIGHT be better than one at a time. But I am unconvinced the results would be that much better. It is true that some of my most serious difficulties resulted from trying to match the original grid lines. This takes far more time in the stick-on process but also in having to custom cut the buss bar components to fit the result. If the results were better, it might be worth it. But they weren't.

Now some details:

1. The release paper used for the inside surface of the grid wires does not provide any visibility. It is too opaque. And so you simply cannot even see the existing grid lines enough to follow them with any accuracy. I say this even after going the extra mile to put 1/8 masking tape over each line in an effort to make it stand out/show through the paper.

2. The release paper has no ability to flex or place the grid wires in any but straight lines. Just forget about anything else. I did not try, as some suggested, to make cuts in the paper to facilitate this. The process is just too difficult to consider doing this as you are sticking things on. And you are severely time limited. From the time you use the special moist cloth to wipe down the window and then dry it off, you have only 30 minutes to complete installing the grid. The instructions were not specific and I was only able to install the horizontal grid wires in about this time. I decided not to sweat the time limit on the buss bars. It would have been impossible to get it ALL done within the time limit even if I had NOT done this line by line.

3. The release paper itself is made sticky. I get this as necessary to make it all work. But from my standpoint, the degree of stickiness is about 3-5 times more than it needs to be. And this makes removing it much more difficult that it should be. I would snip the paper with my surgical snips in the middle of the window and start to pull/tear from there. In many cases the release paper simply would not release nicely and left bits of itself that I had to go back and address. Thankfully, the wires, once stuck to the window, seemed to hold tenaciously enough that the release process worked without pulling them off the glass.

So all in all, the interior release paper is a problem.

4. The buss bars are actually comprised of multiple pieces and need to follow a specific pattern with gaps between them as they cover the grid wires. I am not sure I understand why this is so given that the original defroster just had straight bars with no gaps at all. But the instructions are VERY SPECIFIC. I understand that had I not tried to follow the original grid lines, the pieces included in the kit would have been sized correctly for the grid supplied and most of the pain associated with the buss bars dramatically reduced. But I didn't and so I had to custom cut every piece of the brass strips to follow the pattern. Overall, this makes the buss bars shorter and so the adhesive strip which holds them to the window and the cover pieces must also be custom cut. And at least in my case, this had to be done by sight in the back seat as nothing turned out consistently space to allow for computations and cutting in my shop.

5.The adhesive strips that adhere the buss bars to the window have adhesive on both sides. One is covered with release paper very similar to that used on the grid wires. The other side says 3M on it and is red plastic of some sort. The instructions do not say which side to use where. The 3M side is super hard to start peeling back. I could NOT have done it with the strip in place on the window. I had to fiddle with it using a tweezers in the shop under a magnifier. So I decide to get that side started in the shop, go out to the car, peel off the rest of the red plastic, and adhere that side to the window. I hope that was not an error. But there was nothing in the instructions to clarify it. With the release paper side on the interior, I was able to work with sizing the buss bar strips of brass without fear of getting it stuck in the process by accident. And I could pull back the paper only as far as I needed for the section of brass I was working on at the moment.

6. Above I discussed the "tip" to NOT touch the brass strips of the buss bar and how I had done that to a significant degree prior to the install while trying to make a full scale mock up of the layout. Thankfully, Jeff told me not to sweat that too much and to wipe the brass down with the included wet wipe cloth if needed. Well, there is no way in the world one could manage all the custom fitting and cutting that was required without touching all over the brass strips. So I am glad Jeff chimed in. Again, much of this was due to my decision to try and match the existing grid rather than use the kit out of the box.

Here are photos taken today.

You can easily see my general failure to closely match the lines of the existing grid. You can see from the inside how opaque the release paper is and this makes orienting and following the grid lines near impossible - even it the original lines were straight (and they sadly are far from that).

What you cannot see is that it is nearly impossible to avoid kinks in the wires. After putting them down, I tried to smooth them best I could using an old credit card like a putty knife. You cannot over do it as that might break the wire and then you are totally toast. So all you can do is try to minimize these. There is one case that is severely kinked with the wire a bit twisted so you can see a bit of the copper side from the outside. That should NOT be the case at all. But again, the opacity of the release paper makes it impossible to see from the inside what is going on so this was not really apparent until the release paper had been removed. And by that time, the stuff is down and there is nothing you can do.

So, will this work at all once power and ground is supplied? Will it work, but not well due to the minor and major kinks in the grid wires? Will the contacts achieved to the buss bars be good enough after all that handling and cleaning? Will this work but the kinks and uneven spacing cause bad heating characteristics resulting in a shattered window? Only time will tell!
 
Wow, that's an awful lot of fussy, contorted and uncomfortable work. Sure hope it works well and that you have a big grin every time you flip that switch :)
 
This morning, I tested continuity of all the components and connected the new grid to power/ground. As I expected (but hoped to avoid), I broke the C-Pillar trim piece when trying to do this. Damn! I powered up the grid and I can feel it warming up. It did not feel like it was getting to 140 degrees as Jeff said they would. But it is not easy to tell. I also cannot say if it will de-mist or defog the window and that may take a while to actually see happening since things have finally warmed up here in the PNW.
 
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