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How do I make glass replicas without using actual glass? Answered

Ok, so I have been trying to make a replica for The Phial of Galadriel from LOTR, but I don't have the materials to make a glass replica. Is there a way to make the replica using shape-able plastic or something? I don't have a budget for buying a kiln or other glass-making tools. Does anyone have any tips? (I am also very new to Instructables and I try to make some of the projects on this awesome website)



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1 year ago

plexiglass, or research TKOR sugar glass

Jack A Lopez
Jack A Lopez

Reply 1 year ago

I like this sugar glass idea, and I found an 'ible for a fake beer bottle made from the same, here:


By the way, Plexiglass (r) is a brand name. Not everyone recognises it by that name. Although, maybe fewer people recognise the generic name, which is, PMMA (poly methyl methacrylate)


Also guessing TKOR stands for, "The King of Random." Guessing the vid linked below is their "sugar glass" tutorial.


Reply 1 year ago

And Yup, TKOR rules. Rip Grant Thompson.


Reply 1 year ago

I will call it that from now on. It is the same case with "styrofoam" which is really just a special version of extruded or expanded polystyrene.

Jack A Lopez
Jack A Lopez

1 year ago

PET (poly ethylene terephthalate) plastic, the kind found commonly in many mass-produced clear plastic bottles, can be re-shaped using heat, but it is a subtle art.

The way the manufacturers of PET plastic bottles do this, is by starting with a bottle preform.


Then loading that preform into a blow molding machine.


For amateurs, the method is, in some sense, reversed, because the shape of the plastic gets smaller instead of larger.

That is to say, the amateur method is to start with a PET plastic bottle. Then put a rigid form inside the bottle. Then use a source of hot air (.e.g heat gun or hairdryer) to heat the PET plastic, which causes it to shrink onto the internal form.

I think a Let's Make search for "shrink pet bottle heat"

gives some good examples.

Like I said at the beginning, shrinking PET bottles is a subtle art. By that I mean, it is not easy to produce a shrinked PET bottle that looks symmetrical, pretty, and perfect.

However,the raw material, recyclable PET plastic bottles, is dirt cheap, and easy to find. The same is true of the tools... if you already own a hairdryer or heat gun.

Penolopy Bulnick
Penolopy Bulnick

1 year ago

You could use resin, but you'd need to make a mold first. It's a good alternative to glass since it's clear.


Reply 1 year ago

Ok, thanks for the tip. :)


1 year ago

I know it is a very unusual approch to mold making but I think in this case it could be beneficial.
A few years ago I required a positive mold with a really smooth surface - and it had similar furface challenges as your glass piece.
If there would just be a way to remove thee last surface imperfection AND to get a mirror like finnish....

Well, there is...
For a hollow "glass" piece I modified the steps a little bit:
Make a positive mold for inside of the bottle or if you have something of suitable shape skip and go directly to making a usable negative mold from it.
Two halfs for easy working, like all standard molds if you can.
Please be advised that you need a "neck extension" on your model!
You want a few centimeters extra to be able to joing the final moldswith suffient room.
I prefer quick setting silicone mold material here but anything that provides a smooth surface and half decent stiffness will do.

Next step is to create something for the outside that is big enough to allow you to carve out what you need later.
I guess a suitable alternative would be simple PVC piping.
Make sure the diameter is big enough so that you have enough material to work on your details when the piece comes out.
To cap the pipe at the bottom you can use a standard push fitting.
The key is now to cu some thin wooden disc to fit inside the cap and to glue a popsticle stic or similar upright in the center of that stick.
Literally the same purpose - to hold your ice ;)

Use the popsticle construction as the "bottle cap" for your inside mold - make sure it is properly centered.
Fill the mold with wax:
I prefer a wax with a low melting point and low oil content here.
Do not fill in sections, fill fully, the use a hair dryer or such to keep the top warm while you add more wax to counteract the shrinking.
Let cool fully, then remove from the mold.

Your wax model now goes into the PVC pipe cap and you add a layer of electrical tape to make sure it really is water tight.
Fill with water to get a suitable length for your bottle.
It is prefered to de-gas the water to avoid bubbles but this is optional.
Let the thing freeze sowly.
After a day or so it should be rock solid, make sure the freezer is set to really cold.
Let some warm water run over the pipe after removing the tape so you can pull the ice block out.
Place back in the freezer for half an hour or so.
Now you can fix the frozen piece with some clamp or such and start working on the outside.
Use an ice pick, sharp knifes, chisel or cut copper strips that you heat up to act as a melting tool.
Do not remove too much material!!!
Work quick and have a timer running!
Before the outside starts to melt off you need to put it back in the freezer - that is unless you can work inside a freezer for this...
You can repair minor mishaps with a drop of water and freezing it again.
To finnish the surface place in the freezer, also place some water in there as well.
Once the water start to show the first ice crystal take both out.
Quickly dip your iced piece in some water at room temp - just a quick dunk, in and out.
You should see the water freezing on the surface right away and forming a uniform surface.
If there are still imperfection dunk again in the water you took out of the freezer.
Place the piece back in the freezer for later use.

Hardest step is to get a usable mold from the frozen piece as most mold making materials you can pour won't work at sub zero temps.
I figured a reasonable workaround is to use modelling clay that is rolled into thin sheets.
If placed onto a warm surface and really thin they are extremely plyable.
Use it as a wrapper on the iced model.
You need to make sure the ice is as cold as possible to get a better working time.
Also don't cook the clay ;)
Works best if you have an extra set of hands.
Start with the center of your sheet on the top of the "bottle" - if the bottle is horizontal.
Use whatever tools suits to get the thin clay sheet into all nooks and cavities you created.
It will go really hard really quickly on the ice, so keep what is not in contact away from the ice and try to work quick.
Where the sheets joins on the other side try to get the seem somehwere on the actual outside.
It is easier to fix the finnished model if seem marks are accessible.
Place in a sealed plastic bag back in the freezer when done.
You can try to work in sections by flattening the rim of the used sheet onto the ice but it should be the last resort or used if the piece is quite complex in shape.
For example to do fine engravings first like this.
The plastic bag should prevent a lot of ice build up in the freezer but once out the piece will fog over quickly.
You need to work quick to add more clay for a firm mold as it can be tricky to press it onto the getting wet surface of the existing clay.
Make sure you get proper adhesion!!
Add enough clay to get a big enough mold that is stable enough when cut in half.

Depending on the shape it can be good to push a wire through the center of the mold once the ice is melted away.
If you made sure the shape is suitable to be cut so the seam hits suitable areas you can cut the mold with a wire while the ice is still inside - prefered options as it allows to start over with the mold without carving a new piece.
Of course the best would be if you have an outside shape that can be pressed into a half mold.
Avoids all the cutting issues that migh arise.

Might not be the perfect solution but it works cheap on a hobby level.
For the glass like appearence you can use clear casting resin.
Once done simply melt out the wax ;)