My rear glass on my 51 Bel Air is out and I am going to re-use it however the surface just above where the rubber seal mated is very dirty. I have used glass cleaner and it does not come off-even tried scraping with a razor blade. Does anyone have a recommendation or experience using a glass polish? Photo attached of rear corner glass.
It looks like some residue from the original mounting. Try some Goo-Gone to see if that works. if not, then try rubbing with a rag that you have dipped in some gasoline (but not when you're smoking!!)
I agree that you are probably going to have better results using a chemical cleaner to remove that residue. Glass polish does a great job improve the overall clarity and smoothness of glass. It is such a fine polish that it will not remove much if any physical residue.
Thanks guys for the suggestions. So far i have tried the GooGone, acetone, and Novus #3 polish but not the gasoline. Also tried to locate a glass company that could tackle the job but no luck there as it seems they have all given it up as due to labor cost it's cheaper to just replace. I might try some rubbing compound with a buffing pad on my Dremel. Might be a couple days before I get to it but I'll let you know the results.
Ideally you need to try to determine what the heck the "dirt" actually is.
If it's truly just aged environmental dirt that is baked on by father time, you need something to soften it without the cleaning product penetrating the laminated layers of the glass. Some kind of thick, foaming water based cleaner that you can let sit for hours while keeping it moist. Even resoaking rags with simple green, water and Dawn, shaving cream, paste made with toothpaste, etc could do it.
If it is chemical based residue on the glass from waxing, paint overspray, etc, then soaking with a solvent should do it. You will need to experiment to determine if it's lacquer based, enamel based, etc and try a few chemicals, again keeping it moist for hours.
Abrasive blasting with a soft media like crushed walnut shells or plastic beads will quickly remove water or chemical based layers of gunk from glass without doing any damage to the glass. A steam based cleaner like the "As seen on TV" infomercials should work too but too much heat could damage the glass so proceed slowly.
1938 Canadian Pontiac Business Coupe (aka a 1938 Chevy Coupe with Pontiac shaped front sheet metal - almost all Chevy!) 1975 4-speed L82 Vette
Some good info Tim-had not thought about soaking but will give it a try. i did use a little 2000 grit paper on a small spot and it did come off so I am guessing it is residue that accumulated over time.
We used to clean glass test tubes etc in high school chemistry class using acid. The one used was hellish strong and called aquaregia. It is a mixture of nitric and hydrochloric acids and the sum is much greater than the parts. Never the less, it didn't etch the glass at all.
I would not recommend using an acid any where near that strong. But maybe you could dip a corner of the glass in something more reasonable and accessible? In fact, if I were you I'd get some glacial acetic acid (a very strong version of vinegar) and soak one corner of the glass for some time and see what happens. If that doesn't work, try muriatic acid.
I have one piece soaking in a soapy water overnight. will see how that goes in the AM. If that does not work i am going to try hand sanitizer, It works great for removing pine pitch so maybe it will help. Not too crazy about using acids but I do have an acid product I use for cleaning my woodworking saw blades.
You can also try waterless hand cleaner. It takes grease and oil out of clothes Muriatic acid is 35% hydrochloric in water. Works well on hard water deposits, rust and similar stuff.
I had the same staining on all my original front and rear glass. I used some metal prep for cleaning the surface before painting and a scrubbing pad. On the pad, try to find one that is not too aggressive. There are different grits just like sandpaper. I believe the darker the color, the more aggressive the pad will be. And a large portion of patience.
Well none of the above worked so I used Busch aluminum polish on a Q-Tip . It required as Hawkeye said lots of patience but it did remove all the dirt though there is still what I will call etching. I don't see any evidence of scratching or dulling as the glass looks clear. I will also try Hawkeyes suggestion as the metal prep is phosphoric acid. Photo attached of glass after partial cleaning. In the photo the dark line on the left went all the way around the glass. The dark wavy line seen on the right is shadow. Just to update I used both the metal prep and the polish at the same time with the scrub pad and am pleased with the results. I will continue to do the rest of the glass in the same manner.
Last edited by m006840; 02/07/2208:11 PM. Reason: Photo added
Chipper is correct. There are specific compounds for polishing glass. I use the Griot's Fine Glass Polish with their 3" glass polishing pads on a random orbital polisher.
It is not so aggressive that it leaves swirl marks but does a nice job of smoothing the glass. I was surprised how well a polished windshield sheds rain water and the wipers work better. My wife accused me of putting RainX on her car after I polished the windshield. She does not like the way it makes the water slide off the glass.
Thanks Rusty for the info. What I am learning from this post is there is a difference between polishing and cleaning. The black lines seem to be coming off OK and I am guessing it's mostly built up grime and dirt. Once I have finished the "cleaning" I may do a "polish" of the complete glass.
I was the assistant director for the Columbia River Region for quite a number of years. My wife and I used to organize "Garage Nights" once a month in the summer. We would occasionally solicit Griots in Portland. One member would bring his '63 Nova. He got several 1/2 services as a test vehicle. Claying of 1/2 of the paint on the hood, polishing of the aluminum trim on one side, and polishing of 1/2 of the windshield with their glass polish. Actually worked well.
On a project 55 Chev panel truck a long time ago my dad showed me you could use tooth paste on glass. Took a lot of patience and elbow grease but it did work. It got rid of a lot of the wiper crazing on a 30 year old windshield.
I did purchase Eastwood's glass and polishing kit, years ago and ended up having to buy new glass.
John
1954 Belair Sport Coupe 1960 2 door Impala Hardtop 348/340HP 4spd 1962 2 door Impala Hardtop 409/409 4spd 1962 2 Door Biscayne Sedan 327/250 Auto 1977 Monza Mirage 305 4 Speed 1988 Celebrity Wagon 2018 GMC Sierra 2500 HD Diesel
The glass after basic cleaning looks good although it's amazing how many fine nicks and scratches there are. With the price of Bel Air glass I can live with some minor defects.