More Suction!!

April 26, 2007 10:15 AM

I bought a car GPS unit a couple of months ago and it came with a windshield mount that uses a suction cup. I have had a helluva time getting the suction cup to stay on the windshield. I've tried the trick I learned playing with rubber dart guns as a kid -- basically licking the cup so that the saliva helps hold the seal -- but even that doesn't keep the thing stuck on for long. Any ideas?
posted by briank to Grab Bag (24 answers total)

Aside from crazy glue?

Make sure that the glass you're sticking it to is super clean.
posted by drstein at 10:21 AM on April 26, 2007

WD-40
posted by IronLizard at 10:25 AM on April 26, 2007

Best answer: Rubbing alcohol works wonders.
posted by BiffSlamkovich at 10:28 AM on April 26, 2007

Best answer: Clean both surfaces with rubbing alcohol, allow to try, then dampen the suction cup and it should stick better.
posted by bondcliff at 10:31 AM on April 26, 2007

er, try = dry.
posted by bondcliff at 10:32 AM on April 26, 2007

When you say it doesn't stay on for long, do you mean it falls off while you're driving, or falls off if you leave it up in the car when you park it? Mine will fall if I leave it up while parked, and the instructions say it has to do with sunlight heating up the windows. I just take it down and put it up each time I use it.
If it's falling off while driving, though, I don't know what to do about that. Clean glass as suggested above would seem to be the best bet.
posted by katemonster at 10:33 AM on April 26, 2007

Perhaps the thing to do is to glue it on with silicone rubber. If you ever want to remove it, a knife will work fine
posted by Steven C. Den Beste at 10:35 AM on April 26, 2007

Our GPS unit (Garmin 340, I think) has a small lever that you push to help the suction stay suctioned. When you want to remove it, you pop the lever back up and it comes right off. Maybe you have one of these levers and don't know it?
posted by mbd1mbd1 at 10:40 AM on April 26, 2007

Best answer: Clean it for sure, but also put it on hot. If you put it on cold and then turn on the heater (or park in the sun) the air inside the cup will expand and reduce your adhesion.
posted by DU at 10:41 AM on April 26, 2007 [1 favorite]

Perhaps you need a better mount. Panavise has a variety of mounting brackets that attach to that mount. Note that Panavise's website kinda sucks. Ask for a free catalog and peruse their options.
posted by fief at 11:12 AM on April 26, 2007

Response by poster: I've jumped the gun a bit and marked a couple responses as best answer because they seem to fit the circumstances. I just went out to my car, cleaned the windshield with some alcohol wipes and re-attached the mount. I'll let you know if it sticks. Thanks.
posted by briank at 11:17 AM on April 26, 2007

If it doesn't work, promise you'll try the wd-40. It doesn't dry as fast as spit (and I'm rather curious to see if it'll work without sliding down the windshield).
posted by IronLizard at 11:58 AM on April 26, 2007

My Siruis Sat. Radio mount has 3 suction cups. On a hot Louisiana day, 1 usually gives out. I would look for a mount that has more cups. Justanidea.
posted by winks007 at 12:21 PM on April 26, 2007

A denture adhesive such as Super PoliGrip® works wonders in these situations.

Caution: never leave it the same drawer as sexual lubes...

I'm just saying.
posted by cinemafiend at 12:24 PM on April 26, 2007 [1 favorite]

I don't know what brand of GPS unit you have, but like the Garmin unit that mbd1mbd1 mentions, the TomTom also has a lever near the suction cup that attaches/detaches the device from the window. More complex than your run-of-the-mill suction cup and it won't really work unless you use the lever properly.
posted by Jeff Howard at 1:23 PM on April 26, 2007

As others mentioned, cleaning the surface is important.

The other thing that I do: Instead of licking the suction cup, just breathe on it the way you would breathe on your glasses before wiping them clean.
posted by qvtqht at 1:24 PM on April 26, 2007

Counterintuitively, I have had great success -- based on a manufacturer's promptings -- in sticking devices to windows by using facial oils rather than saliva. Somehow permits a better seal.
posted by Clyde Mnestra at 1:46 PM on April 26, 2007

Clean it with wet-wipes, which contain alcohol.
Also never store the unit in the glovebox overnight - it will get cold.
posted by Lanark at 2:07 PM on April 26, 2007

The suction cup mount for my GPS worked for a year or so, but then started coming off mid-trip. It was kind of unnerving to watch my $600 GPS fall off the window. So I've started keeping a roll of white duct tape in the car (it's less sticky than the 'real' stuff), and I reinforce the mount with two small pieces of tape. I take it off at the end of the day so that it doesn't adhere too much.
posted by bchaplin at 3:15 PM on April 26, 2007

Clean the surface well. Apply a thin smear of silicon grease (grease, not sealant, and extremely thin) to the suction cup. Apply when warm.
posted by Pinback at 3:21 PM on April 26, 2007

I had the same problem, and I can't use any of the suggestions that leave a tell-tale ring on the glass, because where I sometimes park, that's a signal to thieves to break in and look for the hidden GPS unit. I leave the suction cup and bracket at home, sandwich the GPS unit between two small sheets of foam, and wedge the sandwich between the dash and the window. It works in my car, but probably depends on the contour of your dash and window. Make sure not to put undue pressure on the antenna (assuming that's the top edge of your unit, too): wedge sideways, not back, or it will crack.
posted by daisyace at 6:39 PM on April 26, 2007

I've had success using Armor All Glass Cleaner on the windshield and moistening the suction cup before attaching my Garmin mount to the windshield. Be careful when it's hot - if you leave the mount up there for more than a day or two, you will leave some of the rubber on the windshield and never get a good seal again.

Not that it answers your question, but for my car (late-model VW Jetta) I attached the metal disc that comes with the mount to a hockey puck; I put the puck in a cubby underneath the dash with the suction mount attached, and have the GPS right behind my gearshift lever. No windshield mount, totally stealth and rock-solid.

I'm considering going with one of these for when I'm not in my own car. Don't have to worry about the suction cup falling off (which bedevils me in rental cars when I don't have my glass cleaner with me, usually just as I'm merging onto the Cross-Bronx Expressway), and it's quicker to pull it off the dash to hide when the car's parked.
posted by gazole at 9:38 AM on April 27, 2007

Response by poster: To wrap this up:

It has been about a week and I have not had to re-attach the suction cup since using the highlighted recommendations, despite the interior of the car getting warm in the sun on several occasions, so I consider that a successful resolution.

Thanks.
posted by briank at 11:35 AM on May 2, 2007

Thank you for following up.
posted by IronLizard at 12:25 PM on May 2, 2007