Removing a dash cam from glass in extremely cold weather

[GTA Driver]

We are returning a leased vehicle to the dealership. It has a remote starter. Our mechanic has an associate that removes these things and the guy removed most parts with the exception to the sensor mounted to the glass. He claims it was so cold, if he tried to remove it would crack the glass. I told him I would remove that part on my own with a hair dryer. With more thought, I may run the car, get the heater running and get the front window defrost on for a few minutes. I have a thermometer and may start using my dash cam removal strings that came with my A118c2 and A119 when the cabin reaches 15 c / 60 f. Credit cards too.

So has anyone removed a dash cam in temperatures less than -15 c ( 5 f) outside temperatures. Any tips or tricks.

 

[Nigel]

At -15C, a hair dryer may crack the glass if you are not careful since the part that gets hot will expand as it heats up and the surrounding glass will not heat up because the heat is being lost too fast. Using the car heater for a while would make it much safer, then use the hair dryer on the mount for 5 minutes so that the heat works its way through the mount to the adhesive, don't get it too hot, give it time to warm through instead. Maybe cover the glass with a blanket before using the car heater so it does warm up properly.

If it has been on there for a long time then you may end up with some residue stuck to the glass, a small amount of petrol is very effective for removing this, but make sure you have plenty of ventilation to prevent an explosion!

 

[SawMaster]

Any tips or tricks.

Sarcasm warning
1- Move to Florida
2- Wait for "global warming"

Seriously, do pay heed to not concentrating heat on a cold windshield. Even here in the southern US where it doesn't get very cold that can crack your windshied On the solvent I'd try less-active ones first like alcohol, then moving up a step at a time. Don't forget to lay an old towel on the dash to catch any drips

Phil

 

[Nigel]

Sarcasm warning
1- Move to Florida
2- Wait for "global warming"

When global warming really starts to take effect, Florida will be under the sea, which definitely won't help with removing the mount!

Current average height above sea level is 1.8m for Miami

 

[Ralph2]

Seriously.. do not apply heat to a cold windshield (and you take your chances with any heat applied to a warm windshield as well). Take your car into a warm garage.. car wash... and wait till the car warms up. Or.. abandon the sensor mount.. cheaper to replace it than a windshield.

 

[SawMaster]

When global warming really starts to take effect, Florida will be under the sea, which definitely won't help with removing the mount!

Current average height above sea level is 1.8m for Miami

More sarcasm warning
California will fall into the ocean via "the big one" first raising the ocean levels even more According to the end predictions, if all the icecaps melt I may have to move uphill a few blocks. I don't think I'll be around to care about it by then.

Phil

 

[Nigel]

More sarcasm warning
California will fall into the ocean via "the big one" first raising the ocean levels even more According to the end predictions, if all the icecaps melt I may have to move uphill a few blocks. I don't think I'll be around to care about it by then.

Phil

Doesn't matter if California falls into the ocean, it will just climb back out due to continental drift

 

[GTA Driver]

Seriously.. do not apply heat to a cold windshield (and you take your chances with any heat applied to a warm windshield as well). Take your car into a warm garage.. car wash... and wait till the car warms up. Or.. abandon the sensor mount.. cheaper to replace it than a windshield.

Its a family members car. Using our garage as she has another vehicle. I haven't spoken to her since I got advice here on how to go about this. I sent her a text call me. Apparently we may take back to the dealership and let them worry about it. Its -19c now. I don't know if we can get a replacement mount.

Years ago, I got a stone hit on my front windshield in similar weather. The result was hardly visible. Car was running much of the day and early evening several hours after the hit. When I woke up the next day and looked at my car, there was a crack ... to the entire wind shield.

It makes me appreciate what @viofo is doing with having two mounts in their packages all the more. However you only get one GPS mount, but a replacement GPS mount is a lot cheaper than a new windshield. My front a119 with GPS mount, it may need to be moved 1/4 inch and my other front camera doesn't have an even picture after 4 years of being pushed with me going for the event button. I will fix all of that .... in warmer weather.

 

[Dashmellow]

I live in New England where the winter temperatures can become quite cold, especially this season where we have had relentless arctic temps in the single digits or below for about two weeks now due to an unusually intense and sustained polar vortex. This morning when I awoke it was -3º below zero Fahrenheit (-19.44º C). Tonight we are expecting temps of somewhere between -15º to -20º below zero Fahenheit (-26.11º C - to -28.88º C)!

So, I mention all this because I have a bit of experience with 3M VHB tape in such cold conditions.

If you carefully insert a putty knife under a corner of the glass mounted sensor and give it a gentle twist or two back and forth while continuing to push the knife forward there is a reasonable chance that the whole thing will simply pop off in one go. You'll know pretty quickly whether to keep applying force or to abandon the effort.

For several years now I have used a sharp, thin bladed putty knife to remove 3M VHB mounts from windshields and have never once experienced any scratches or other issues. Works far better than string and offers much better control and leverage. Just use care and common sense.

 

[Nigel]

If you can get it down to -40 then a sharp tap with your knife and it should just drop off since the adhesive will have solidified!

 

[GTA Driver]

They ended up returning the SUV without removing the sensor. The dealership said they would remove it, but when it was returned they said it was too cold. Which means buying a new sensor. I would imagine it means getting new fobs too. Also some remote starters are unsuitable for some vehicles.

I think on a remote starter or a "cylinder" shaped dash cam where thru an arm it connect directly to the wind shield, unlike a mount with some wedge camera, best to kiss them good buy. As some wedge cameras have two mounts or easy to acquire GPS mounts, best to get one of those than risking a window.

Where it gets complicated is you have a multiple cameras on the front or very expensive ones.

If I were to remove one of these things, the only thing I would add to all of the suggestions is to get use some unused thermometers or get some. A dollar store had large display ones for cheap. I would put them on the windshield before putting a blanket or comforter like @Nigel suggested and have a thermometer in the cabin in the car. When the inside temperatures reaches '50 f then I would start with the hair dryer

 

[Ralph2]

When the inside temperatures reaches '50 f then I would start with the hair dryer

You take your chances with cracking the windshield ANY time you start adding heat. The tiniest rock chip will start a stress crack. In colder climates it is very common to see a horizontal crack just above the wipers.. caused by cold snow left at the bottom of the windshield and defroster on high.
Heat.. cause expansion.. glass does not stretch / expand well.