window defrost grid

[AK260]

The only other consideration may be that if the paint itself isn’t resistive (I.e. it’s purely conductive) you will create hot and cold spots that may break the glass on a cold day. I have read about people fixing their modern cars and having this issue.

Well done for the tenacity and effort to make it work - you need to employ an artist with a steady hand!!

I am very much going down the frost fighter route. On my car, the grid has 16 elements with 35mm separations resulting in a grid height of 52.5mm

The frost fighter 16 element jobbie ends up as 50.8 - there HAS to be a way to make their product work for us.



It’s definitely worth asking them if they can do a custom size - but even with that, i wonder if the original silk screen has to be rubbed off for good adhesion?

[Dave WM]

I would think you want it clean to start just to avoid chaos looking lines.

[AK260]

Agreed! Completely!! The question is, just how does one get the silk printing off? It’s very hardy stuff! ;)

[Dave WM]

the trial wipe with glass cleaner and a paper towel worked well no effect. I get about 2 ohms per inch on the 1/16 stencil line.

[Dave WM]

I am hoping that the remains of the old grid act as a good surface for applying the new paint. So far I have done test application on only smooth clean glass. The rough texture of the old grid may help with the stencil on new adhesion..

Edited September 8, 2020 by Dave WM

[Dave WM]

2 ohms per inch X 34 inch per line=68 ohms per line, 16 lines in P = 68/16= 4.25 ohms, 12v/4.25r=2.8 amps,2.8*12=34 watts.

Think I did that right sound like enough power to warm the glass. can you check on this captO

oh and the stencil lines are about 50% wider than the orig at least from what remains. the stencil is for 1/16.

My plan is to remove the hatch for better access, then do one line and confirm the resistance. My biggest prob right now is trying to figure out how to remove the hatch by myself. maybe the boss can help, but sometimes that does not go well. maybe rig up a carrier that loops around the top and bottom and use the cherry picker to hold it while I remove the hinge bolts.

Edited September 8, 2020 by Dave WM

[AK260]

2 ohms per inch X 34 inch per line=68 ohms per line, 16 lines in P = 68/16= 4.25 ohms, 12v/4.25r=2.8 amps,2.8*12=34 watts.
Think I did that right sound like enough power to warm the glass. can you check on this captO
oh and the stencil lines are about 50% wider than the orig at least from what remains. the stencil is for 1/16.
My plan is to remove the hatch for better access, then do one line and confirm the resistance. My biggest prob right now is trying to figure out how to remove the hatch by myself. maybe the boss can help, but sometimes that does not go well. maybe rig up a carrier that loops around the top and bottom and use the cherry picker to hold it while I remove the hinge bolts.

Nice work! That should definitely add some warmth! [emoji106][emoji106]

And on glass removal, don’t even!!! Get a friend around with a face mask, you will kick yourself if you damage bodywork or drop the glass!!! Especially after that hard work!

[AK260]

2 ohms per inch X 34 inch per line=68 ohms per line, 16 lines in P = 68/16= 4.25 ohms, 12v/4.25r=2.8 amps,2.8*12=34 watts.
Think I did that right sound like enough power to warm the glass. can you check on this captO
oh and the stencil lines are about 50% wider than the orig at least from what remains. the stencil is for 1/16.
My plan is to remove the hatch for better access, then do one line and confirm the resistance. My biggest prob right now is trying to figure out how to remove the hatch by myself. maybe the boss can help, but sometimes that does not go well. maybe rig up a carrier that loops around the top and bottom and use the cherry picker to hold it while I remove the hinge bolts.

Nice work! That should definitely add some warmth! [emoji106][emoji106]

And on glass removal, don’t even!!! Get a friend around with a face mask, you will kick yourself if you damage bodywork or drop the glass!!! Especially after that hard work!

[Patcon]

10 hours ago, Zup said:

That was lifted from frost fighters website.

Apparently there is no residual material after application---only the lines.

A purpose built grid that matches in lengths, spacing and element thickness should be as close to original as one is probably going to get and in my mind would likely be a better performer than a mix of old and repaired segments or a new conductive grid with irregular thickness (hence resistive) properties.

I appreciate your "do it myself" approach and applaud you for it. My only intent here is to see if there is interest in a quality one source solution that virtually anyone can purchase and install with a minimum of hassle and a maximum of performance.

So good to see you around Jim. Will miss seeing everyone at Zcon...I would be in for at least 2 grids, maybe 3

@Dave WM

I think I would want a solvant based product and in enough bulk to use a touch up spray gun

[Patcon]

I would think a good buffing compound and a  rotary buffer would take care of the lines

[Namerow]

5 hours ago, Dave WM said:

My biggest prob right now is trying to figure out how to remove the hatch by myself.

I'm sure others have succeeded at this task.  In my case, I used my engine hoist.  I wrapped the hatch using HF-quality cargo straps -- one strap along the vertical centreline, the other along the horizontal CL.  I used zip-ties at the crossover points so as to make sure that the straps didn't walk under load.  Lift cautiously.  Study the balance. Watch to ensure that nothing shifts.  Make sure in advance that you know where you're going to drop the hatch panel after removing it.  A set of movers' blankets is a good idea for protecting the hatch paint once in storage.

BTW, I successfully re-installed my hatch (a much bigger challenge, BTW) using the same process in reverse.

[zKars]

3 minutes ago, Namerow said:

I'm sure others have succeeded at this task.  In my case, I used my engine hoist.  I wrapped the hatch using HF-quality cargo straps -- one strap along the vertical centreline, the other along the horizontal CL.  I used zip-ties at the crossover points so as to make sure that the straps didn't walk under load.  Lift cautiously.  Study the balance. Watch to ensure that nothing shifts.  Make sure in advance that you know where you're going to drop the hatch panel after removing it.  A set of movers' blankets is a good idea for protecting the hatch paint once in storage.

BTW, I successfully re-installed my hatch (a much bigger challenge, BTW) using the same process in reverse.

And masking tape on the roof around the hatch hole where the hatch might touch too. Hood is easy one man, hatch not so much...

Take the hatch strut off first. Not that I’ve ever forgotten to....

Edited September 9, 2020 by zKars