Where to get 12mm dia flat on both side glass lens?

Marsupial

Active Member
I am currently working with vintage glass top typewriter keys, and would need "replacement glass" for some of the keys. It happens that some keys didn't have glass, some other had broken glass or yellowed plastic instead of glass. I figure using the key with replacement glass would be better than getting just more keys.

I've been looking around, and it seems easy to get 12mm glass cabochon, but not flat glass. Unless it is 20-25mm diameter or more.

I've found the top inserts for microscopes in circular 12mm, but they are awfully thin.

I am sure flat 12mm circular lens exist somewhere... it is just to find it. So, your help is needed - if you have any idea, please voice up!!! :D
 
Does this have to actually be a lens? Isn't a lens curved by the nature of it being a lens?

If just flat glass will do, you should be able to find those in jewelry findings. I know they have the little 1/2 inch mirrors that you might could de-silver. How thick does it need to be or rather how thick is too thick?

Shylaah
 
You could glue the thinner glass togethey using Watchmakers crystal glue.
My local hobby shop carries some,so check if they have any at yours.
 
Shylaah, it would need to be as flat as possible... but I haven't found anything under 20mm that isn't domed in jewelry dept at craft stores like Michael's. Will check about mirrors.

Will also check about crystal glue. Would the resulting "merged" glass be somewhat solid?
 
for real deal lenses; you could try: Surplus Shed
You'd probably want a Plano convex lens, as that's flat on one side and a slight outward curvature; steepness dependent on focal length. Buuuut they are kind of pricey at $4.00 a pop.

On the other hand, like Sidewinder said, you could get someone with a laser cutter than can cut acrylic circles for cheap. There's a seller on etsy that could probably help you out. He cut 50 acrylic circles for me at around $12.00 shipped IIRC
 
Yeah, I got the ones I have from Michael's. It was a mixed bag of sizes, but I think they had the just one size bags. They are 1/2 inch though and that's a little over 12mm, closer to 13mm actually (12.7mm), so not any help if it has to be exactly 12mm. And the ones I have are about 2mm thick.

1/2" Round Glass Mosaic Tile Mirrors - 10pcs

You're right, everything out there in this size is domed/cabouchon :(

Shylaah


Shylaah, it would need to be as flat as possible... but I haven't found anything under 20mm that isn't domed in jewelry dept at craft stores like Michael's. Will check about mirrors.

Will also check about crystal glue. Would the resulting "merged" glass be somewhat solid?
 
Is it easy to remove the mirror without scratching the glass?
13mm would be good, as long as it is less than 14mm it will fit in there. The typewriter keys are 14mm with the inner ring a bit under 12mm ID. I'll go to Michael's today. Michael's in Quebec are still brand new (opened last month) so I hope they do have what's available in US Michael's...

Otherwise I'll look for laser-cut... I was looking at cutting glass, but never found tools under 25mm (what's with 20 and 25mm anyway???) - it didn't occur to me that laser cut would work like a champ, and that there'd be people here who could do that. I like this place :D
 
There actually is a product, Mirror Silvering Remover, that takes all that stuff off the back of mirrors......kind of expensive though if you only going to do a few little mosaics......
MSR - Mirror Silvering Remover 16oz

I tried scraping the backing off with my Xacto knife, it's hard to get off, and I can't really tell if it's scratching it. The mirrors don't cost much so you could afford to experiment with them. There were some "home remedies" come up in Google search, but they seemed rather "involved"......

Laser cut would be great if you can get them, save the mirror tiles for an "if all else fails" project!?

Shylaah
 
I got the same "mix bag" at Michael's - they have "single size" but only in bigger ones. The mix bag has 9 "1.2 cm" (close to 13mm) that I can confirm fit in the keys. They are a bit wider and a bit thicker, but would work. I'll experiment removing the silvering on the bigger ones - I have plenty that will only end up in my "useless parts" bin.

Think acetone would work dissolving that? (Time to go google hunting :D)

The mix bag here is 3.50$ - for 9 keys its not exactly cheap.
Would the laser cut ones be acrylic? I am wondering if it would be dangerous to get scratchy... they'll be "hit" somewhat regularly, being that I'll use them on a keyboard. Although, the most used keys will be real glass, and fingers hitting a key isn't "hard contact". I'll still hunt that maker down on etsy. if I can get 50 for 12$, its a great deal.
 
Mirror soaking in acetone for half an hour seems to have little to no effect. I see online people talking about paint remover, but also about various acids - phosphoric acid and muriatic acid seems to be mentioned several time.
I am fresh out of paint remover, will see if I can get a small quantity and try it out.

Other than that, haven't found the etsy laser etcher yet. :( There are a few that cut acrylic shapes, I guess I will just pick one randomly and ask for quotes for clear 12mm circles...
 
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i might be able to help you. Either this week or on the Friday next I may have something for you. One of my jobs is sorting through piles of military surplus being used in a physics lab, aka tons of lenses, most of which are too tiny to be used. 12 mm you said? I'll see what I can find.
 
Here you go!
lasercut on Etsy
He's pretty personable and had my order shipped the same day I paid. I was surprised at that and it turned out he started cutting the night before based on the conversation we had. All in all a pleasant experience. :):thumbsup
 
I got the same "mix bag" at Michael's ->>>clip<<<

The mix bag here is 3.50$ - for 9 keys its not exactly cheap.
Would the laser cut ones be acrylic? I am wondering if it would be dangerous to get scratchy... they'll be "hit" somewhat regularly, being that I'll use them on a keyboard. Although, the most used keys will be real glass, and fingers hitting a key isn't "hard contact". I'll still hunt that maker down on etsy. if I can get 50 for 12$, its a great deal.

3.50....wow, they were only $1.99 here, mixed bag 25 items 9 were 1/2", 8 were 3/4" and 8 were 1".....and I am sure I had a 40% off coupon or got them when they were having 40% your entire order day......I never pay full price for anything at Michael's or Hobby Lobby or JoAnns :)


Mirror soaking in acetone for half an hour seems to have little to no effect. I see online people talking about paint remover, but also about various acids - phosphoric acid and muriatic acid seems to be mentioned several time.
I am fresh out of paint remover, will see if I can get a small quantity and try it out.

Other than that, haven't found the etsy laser etcher yet. :( There are a few that cut acrylic shapes, I guess I will just pick one randomly and ask for quotes for clear 12mm circles...

Well, you have several things going on altogether on the back of a mirror.....next to the glass is the silvering, over that sometimes a copper layer but doubt these little cheapies have that, then a paint and then maybe a paint sealer.......so if you're not using that magic de-silvering solution, you have to address each layer......

I don't have any paint thinner to experiment with, but I scrapped some of the paint off then used what I saw suggested in a Google search, some toilet bowl cleaner to take of the sliver and it did work, but I had to get the paint off it first......so I think if you had some paint remover to remove the paint, then hit it with the toilet bowl cleaner......unless those two items would add up to be more then the silvering remover.....

The Xactor did scratch up the glass a bit though.......so I wouldn't recommend that approach......

The etsy laser cutter, does he offer glass cutting? All I could see was acrylic he was cutting??

Shylaah
 
I have found someone on etsy that is from Vancouver that can make laser cut acrylic so I ordered a lot of 50. I figure it will do the trick and costs less than the mirrors as bought at Canadian Michael's.

I have enough glass ones to cover the essential keys and I hope there won't be a visible difference between the plastic and glass ones.
 
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That's probably for the best :)......I don't think there will be any visible differences at first.....but there eventually will be, depending on how much the acrylic yellows over time, might be sooner than later though if the yellowing is exasperated by the constant touching??

Shylaah
 
I just received the plexiglass discs. I paid for 1/2"D discs, what I received is a lot closer to 7/16"
It is close to the 12mm I was originally talking about, maybe like 11.8 mm
But the .2mm missing makes that the discs can slip right trough the lips of the keys.

it sucks big time. I suggest you avoid ETSY seller "plasticsmith" - what's the point of using a laser cutter if you end up being almost 1/16" off?
 
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