Render frosted glass transparent with Scotch tape

YouTube user TheFarmacyMan discovered that his workplace frosted glass privacy screen could be rendered transparent by applying a piece of Scotch tape to it. A useful detail for anyone planning a caper novel or a robbery. A user called rawnoodles10 posits "..the glue on the tape fills in the small imperfections on the surface of the glass. Since the glass, the glue, and the tape are clear, filling in the imperfections (the frosting) makes the glass clear."

Weird Tape Effect (via Core77)


  1. This has been around since 2010, and it also was explained, that this only works on the side with the frosting – which normally is the side that you don’t have access to in the first place. So nothing is gained with this “trick”, because you can put as much scotch tape on the flat side of the frosted glass as you like, it will still be frosted on the other side…

  2. This is basically the same idea as something Babbage described:

    I will here mention another mode of treating glass, which may occasionally be found worth communicating.

    Ground glass is frequently employed for transmitting light into an apartment, whilst it effectually prevents persons on the outside from seeing into the room. Rough plate-glass is now in very common use for the same purpose. In both these circumstances there is a reciprocity, for those who are within such rooms cannot see external forms.

    It may in some cases be desirable partially to remedy this difficulty. In my own case, I cut with my diamond a small disc of window-glass, about two inches in diameter, and cemented it with Canada balsam to the rough side of my rough plate-glass. I then suspended a circular piece of card by a thread, so as to cover the circular disc. When the Canada balsam is dry, it fills up all the little inequalities of the rough glass with a transparent substance, of nearly the same refracting power; consequently, on drawing aside the suspended card, the forms of external objects become tolerably well defined.

    The smooth surface of the rough plate-glass, not being perfectly flat, produces a slight distortion, which might, if it were worth while, be cured by cementing another disc of glass upon that side. In case the ground glass itself happens to be plate-glass, the image of external objects is perfect.

    Passages from the life of a philosopher (p. 383)

    1. Among a dozen replies which all correctly assess that this discovery is pretty meh, you sir have brought something pretty frickin awesome to the table. That the prior art on this discovery was Charles Babbage is _really_ cool.

  3. What’s weird to me is that things like this get discovered in 2011. What else are we missing?

      1. Someone needs to post a video of someone watching this video pointing out the spelling and grammar errors.

        /Am I the only one that suspects that lady is a Tea Partier?

  4. Not an issue in privacy as long as you put the frosted surface on the inside of the room you’re protecting.

    e.g. if it’s a shower glass door, the frosting should be where the nekkid people are.

    1. False. If you have ever owned anything that is frosted glass you would know that getting it wet disables the abilities of the frosted glass. So, putting the frosted side on the “nekkid” side would actualy make it bad. In fact, using frosted glass for a shower would be useless as well, that is why I have always used plastic frosted doors, or plexiglass.

  5. Frosted drinking glasses don’t look so frosted when full of liquid. Probably the same principle.

  6. This is nothing new. Same effect if you have a frosted shower door and it gets wet. Only works though on the side with the imperfections, which is weird on MacGyver, since it’s usually on the inside, not the outside.

  7. This didn’t get “discovered” in 2011; it just got put on YouTube in 2011. I’m sure a million people have also noticed that a similar thing happens when you put water, vaseline or any other clear runny thing on frosted glass.

    Other astonishing tape facts: you can write on matte tape in pencil and rub out the writing, repeatedly, without leaving much of an afterimage or damaging the tape. So you can use it to protect the parts of your tabletop RPG character sheet which see the most wear and tear, like the places you write down your hit points and ammo. In fact, you could coat the entire page in tape and make an everlasting, reusable character sheet in case you die and need to roll up a completely different character.

    Let me get my video camera… ;)

      1. Yes, but with a different kind of plastic – normal lamination plastic does not take pencil marks at all, the smooth glossy surface doesn’t provide enough friction.

        If the matte plastic from scotch tape was available in large sheets or for lamination, I would be all over that for RPG maps :)

        In large sheets all I need is some spray adhesive and voilla, home lamination with a pencil friendly surface. I would be all OVER that.

        You used to be able to get rolls of clear, adhesive-backed “shelf liner” at hardware stores, but apparently the natural wood look went out of fashion and they only have the opaque stuff now. It was the closest stuff to this concept, and it still didn’t take pencil very well.

    1. I guess I meant personally “discovered.” I suppose I’d learn a lot of new things if I sat down with a volume of “Hints from Heloise” as well. Oh, and rainbows and magnets are magic.

  8. This is pretty common knowledge.. ever tried washing frosted glass? Does the same thing temporarily.. But of course all of this only works on the frosted side!

    1. But of course all of this only works on the frosted side!

      Really?!? Wow, you’ve blown my mind. But wait, what if _both sides_ are frosted?

    2. I know…I’m thinking that either a lot of bber’s have someone to take care of them(ie male), are really dirty, or just haven’t ever used a shower with doors. I am leaning toward a combination of male/really dirty given mostly because it amuses me.

  9. Smearing glycerol (n~1.47) on the glass (n~1.51) should make it almost as clear as though it were never frosted if the frosting is merely fine scale etching and not painted- it’s the refractive index that matters. drop a piece of glass into glycerol!

  10. What’s thoroughly amazing about this is the fact that anybody is amazed by it.
    I’d have thought that it was common knowledge, surely, to everybody above the age of about eight, we learn the basic principle when we dip dull matt pebbles, or seashells in water, then admire their beauty.
    Clear adhesive tape, or varnish, or Babbage’s Canada Balsam all work in the same way.

    If sticky-tape man works in a pharmacy, that’s truly worrying.

  11. The headline next week will be geek arrested under DMCA for circumventing security feature in frosted glass technology.

  12. I’m surprised by all the surprise. Weren’t any of you people kids at some point? I thought everyone had tried this before.

  13. Since the glass, the glue, and the tape are clear, filling in the imperfections (the frosting) makes the glass clear.

    The problem with this explanation is that air, which is what was inside those imperfections in the first place, is also clear, yet it did not have the same effect. The missing link is probably that the adhesive and the tape also have a similar index of refraction to the glass.

  14. didn’t know that about frosted glass, also didn’t know a youtube URL could start a video anywhere on the timeline, thanks RobDubya

    two facts for the price of two Boings!

  15. Grease on paper works well, too. Many years ago, a secretary where I worked showed me a trick… she sprayed people’s pay envelopes with circuit cooler (freon or similar, I believe) and could read the pay amounts inside. When the coolant evaporates, it leaves no trace. Why she admitted the trick to me, I have no idea.

    1. Greased paper was also once a common window pane material, before cheap glass (but after cheap paper). The grease helps weatherproof the paper as well as let more light in.

  16. This is similar to a technique lapidaries use to find the best portion of a gemstone to use. The rough material is covered with a clear epoxy, which sinks into crevices in the stone. The underlying color and pattern is revealed, and the epoxy is either dissolved with a solvent or ground off as the stone is formed.

  17. Only thing I would say with this is WATCH OUT!!! Some places, especially banks, are now using a vinyl laminate that gives the effect of a frosted surface.

    The stuff is very thin and scratches very easily, so if you put tape on it and scratch it up, you might put a hole in a $200 sheet of material!

  18. and to think: I’ve been using my face grease to turn these things transparent all along.

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