removing hard water deposits on glass?

The materials used to build my greenhouse are almost 100 years old. Much of the glass has white mineral deposits on it - I'm assuming that's what they are. It is still quite usable, but I'd like to remove the white stuff if possible. I scraped paint off of them with a paint scraper when we put the greenhouse up, but the deposits remain. Any suggestions? Preferably ones that won't damage the wood framing or the paint on the wood framing.

Plain white vinegar might do the trick, we use it here for hard water crud left behind.

If the vinegar doesn't work, try cheap bottled lemon juice. Wipe on and let stand. After a bit the mineral deposits should soften so they can be rinsed or scraped.

If the vinegar or lemon juice doesn't work, there is a widely used product called CLR, (Calcium, Lime Rust) that is carried by every hardware store. You would have to read the instructions to see if it would harm the paint or the wood.

When doing the work make sure the area is well ventilated as the acids in any of the products mentioned above when combined with the hardwater stains, (calcium carbonate) will give off gases. After you remove the the deposits, rinse with distilled water and apply Rain-X per the instructions.

It is a good idea to get rid of the calcium carbaonate deposits as they will provide a substrate for algae and mold to grow on.

Sonny

Remember that glass is permeable and will "etch" over time from these minerals.
You May not be able to ever get the glass to it's original clear state.
If I were you I would call a glass installation co. in your area and they will give you information on
products and costs to clean/replace.
Good Luck.
Julie

Most of the glass isn't too bad, plenty of light still gets through - just a few of them that bug me. I'll try these things once it warms up a bit and let ya know what works.

Snoggle ~ I am finding out that too much light transmission can quickly scorch plants. After hanging shade cloth inside my greenhouse on Feb 28th, I am not sure I would worry overly much about the cloudy glass. Just my two cents.

Yeah, that's a really good point, podster. I guess it's hard to imagine right now with highs in the low 30's. I'm still kinda getting things set up out there, maybe I should watch temps and light levels this spring before I worry about it too much.

Snoggle,

I completely forgot the cheapest and most effective way the take hard water stains off of glass, use a new safety razor blade or razor scraper. Most of the deposits should come right off. Duhhh! LOL

Sonny

Sonny - I tried that when I scraped old paint off of them. The paint removed just fine, but the water stains did not.

if the water stains did not come off with a razor blade then they are etched into the glass.. I dont know of anything that can fix etched glass unless you replace it with new.. but like mentioned earlier you might need it for shade in a few months..

Try the "CLR" before you begin planting & give yourself plenty of ventilation. I know of other methods, but I would replace the glass first if money wasn't a huge issue.

Sonny