I want to glue a piece of steel to my truck's windshield, with some threaded holes so I can attach anything to it (such as radar detector, parking permits etc).
My question is, what sort of steel glues best and what is the right surface prep. Should I sandpaper it? Should I sandpaper the glass? What is that rearview glue exactly?
Also what is the minimum ambient temp at which I can do the gluing.
i
Clean, smooth, flat, and small (large pieces won't mate to the curvature of the windshield -- you want something the size of a rearview mirror mounting button).
No to both.
Cyanoacrylate aka "superglue".
Consult the manufacturer of the glue. Typically 60F and up, I believe.
Yep
Yep
Nope. There are specific rear view mirror glues from Locktite that work very well.
Yes, reasonably warm temps are needed.
The other option would be a somewhat larger plate and some of the 3M VHB very high bond DS foam tape where the foam will help compensate for the windshield curvature.
Pete, thanks a lot, I will actually use that 3M VHB, I was not even aware of it.
I bought this
The VHB tape is pretty good stuff, it's been known to be used on commercial decorative ceiling panels and other overhead stuff.
Flat.
Yes, it can't hurt.
ABSOLUTELY NOT!
Polyester Acrylic Epoxy?
Much higher than in Illinoise in the Wintertime. RTFM, sir. Then don't even consider gluing at anywhere near the low temp. It works better at higher temps. I know this from many reglues in the warmer climes of LoCal. Nearly every wreck that came into the body shop had a blown mirror or broken windshield, so I learned how to remove the tab, clean it up, and glue it on the new w/s.
-- "Human nature itself is evermore an advocate for liberty. There is also in human nature a resentment of injury, and indignation against wrong. A love of truth and a veneration of virtue. These amiable passions, are the latent spark. If the people are capable of understanding, seeing and feeling the differences between true and false, right and wrong, virtue and vice, to what better principle can the friends of mankind apply than to the sense of this difference?" --John Adams
NO-NOT SUPERGLUE! The proper stuff can be had at the auto parts places, it's a two-part glue, vinyl-based, same as OEM. Has enough flexibility to take up the difference in temperature coefficients between glass and metal. FOLLOW DIRECTIONS! Failure to do so will result in the part ending up in your lap at the worst possible time. The stuff I've used was under the Loctite label, has lasted about 10 years so far.
If you're designing something, grab a rearview mirror and mounting button off a wreck and you'll be miles ahead. Usually a couple of bucks for the non-powered kind from a U-Pullit. Put your holes in the shoe that mounts to the button, not the button itself. Another thing to check is local and state laws about stuff around the rearview mirror, some states are picky about having absolutely nothing except the mirror on the windshield. Tickets for same can be costly.
Stan
IIRC the stuff that I have in my '69 Chevy was one-part, and it was a strong enough bond that when my (then) six year old kid kicked the mirror off in a tantrum, it took some glass with it. Fortunately a bit more of the same glued the whole mess back on; the kid's 17 now*, so you can't say it doesn't last well.
Tim Wescott fired this volley in news:icOdnWYMCujoWGfRnZ2dnUVZ snipped-for-privacy@web-ster.com:
Most of them are, except that they use an "activator". It's not truly a two-part system. The activator merely kick-starts the naturally slower cure process. I has only to make contact with one side of the film to have its effect, sort of like "Zip Kicker" for CAs.
But Mirror Glue isn't a CA. Last one I used was a Methacrylate, similar to some thread-lockers, but transparent.
LLoyd
Goop - any available flavor...
Be aware that it may creep under load in summer, and fall off. Consult datasheet for details and limits.
As for windshield curvature, given that this is a one-off, one can simply machine a steel pad to fit the windshield using a CNC mill.
Joe Gwinn
I tried some of that rear view mirror glue once ages ago, and the mirror fell off again in a couple weeks. I followed the instruction on the back exactly. I sanded the puck and the glass and put it back with JB Weld. It stayed. Infact when the car was junked I tried to save the mirror because the one in my truck then was cracked. I had to break the windshield and grind off the glass to get the puck.
It sounds like you didn't hold it tightly against the glass for about two minutes. I've seen guys tape 'em up after pressing them on, but that doesn't work. YOu have to expend the time and energy to hold them tight and immovable against the glass for at least 120 contiguous seconds or the bond fails. DAMHIKT @ $5 a pop in '70s dollars...
Wouldn't a buck at a junkyard have been cheaper in the long run?
-- You can't wait for inspiration. You have to go after it with a club. --Jack London
Junkyard? Is that where foolish city folks throw away perfectly good stuff and let somebody else make money off of it?
It was a bit of a drive to the nearest junkyard from where I grew up.
When I finally made the pilgrimage to a junkyard I was floored by them asking new prices for used wore out parts. I have heard they have better junkyards back east, but...
Hmm ... I used the rear view mirror glue also -- following the directions o the back -- and it lasted until the front windshield had to be replaced because of a rock crack. (FWIW, the car was a Mazada Navajo (like a Ford Explorer, but two-door.)
IIRC -- there was a container of solvent in the kit which you had to break and quickly scrub the area of attachment -- both the mirror stem and the window surface.
Enjoy, DoN.
I needed a replacement overflow tank for my Nissan Patrol. Went to a wreckers to see availability. $44 for used genuine, $86 for new aftermarket version. Rip-off merchants. I searched Ebay and bought an identical aftermarket version for $29.50 including delivery. Ordered Thursday evening, delivered Tuesday morning from Melbourne, Vic to Darling Downs, an outer suburb of Perth, WA, something like Houston, Tx to Seattle, Wa in distance.
Alan
I went three or four years with an annual reglue of the mirror puck (with careful sanding, cleaning with alcohol, and use of the solvent) in my old Lebaron, using the "official" cement (once bought from Chrysler, other times from NAPA). When I gave up and JB Welded it, it stayed on from then until we sold the car, probably a decade or more later.
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