Easy Mold Using Hot Glue

by Amit_Jain

2.5K1217

Intro: Easy Mold Using Hot Glue

Hi All,

Last year I carved a Moai Statue out of a "plaster of Paris" block. I received many requests from my friends for one. Carving a new Moai statue is not very difficult but carving 5 to 10 such statues is too much effort for a lazy fellow like me.

I explored (googled) on how to make molds and found silicone as the best choice, but using silicone, is expensive in India. Cheaper alternate is Alginate, but cannot reuse... There are alternate methods using hot glue or silicone sealant.

In this intructable I will share how to use hot glue gun to make a mold.

STEP 1: What Do You Need?

  • Hot Glue Gun
  • Play Doh
  • Moai Statue
  • Plaster of Paris
  • Paper Knife
  • Oil

STEP 2: Preparation

  • Make sure the master object is water proof and smooth
  • I painted my Moai statue with varnish
  • On a play doh, insert the Moai statue half way through
  • Make sure edges are clean
  • The play doh should be sas flat as possible
  • Apply oil on the surface on the doh and statue

STEP 3: First Half

  • Let the glue gun get hot for 5 to 10 minutes
  • Start from the bottom go upto the top
  • Move slowly upwards, cover all surface
  • Cover everything
  • Leave it to cool for 10 to 15 minutes
  • Remove the play doh
  • Gently de-mold the statue and inspect if there are any holes
  • If any holes are found, apply small quantities on hot glue

STEP 4: Second Half

  • Place the statue in the first half of the mold
  • Apply oil on the exposed part of the statue and the first half of mold
  • Pour hot glue starting from bottom towards the top
  • Cover all of the statue
  • Leave it cool for 10 to 20 minutes

STEP 5: De-Mold

  • Gently slice the hot glue at teh joint of first and second half of the mold
  • Cut across to open like a book as in the picture
  • Remove the original statue

STEP 6: Test

  • Using a tape or thread, hold the two molds together
  • Pour a mixture of "plaster of Paris" and water in the mold
  • Let it dry for 20 minutes

STEP 7: Conclusion

  • I was able to replicate simple design using Hot glue
  • There were some bubbles that I need to work on during the pour
  • I will add a larger slot for it in future

I hope this instructable was useful and share your comments, On How I can improve this or make cheaper molds to replicate statues

Thanks

11 Comments

NitsanS1 5 years ago

Good job,
During my studies I was creating a very similar method of molding and here are few thoughts of mine:
1. you should add a small tube to the model to create a flow hole
2. the glue gun plastic is VERY sensitive to heat (so much so that even when you play with it a lot, you can leave indents and marks of your warm fingerprint) so a thermosetted material like epoxy (and even large models of plaster) could generate enough heat to make the mold slightly deform while they are reacting and setting, so mind that.
3. you could actually put several sticks in a pot, heat it up a bit and make a pouring variant to this method (with longer cool time), make sure to wear mask when doing it (because it smells, and probably not as healthy).

that's it, nice instructable.

Avatoon 5 years ago

There are a lot of applications for this. Really good job showing a great and cheap moulding technique. Definately voted!

Amit_Jain 5 years ago

Thanks, Please share if you have ideas

AnandM54 5 years ago

Nice try friend... Simple way and nicely did it.. Great idea !!

Gadisha 5 years ago

That's such a cool technique! :)
Thanks for sharing, I 'll keep this in mind.

Amit_Jain 5 years ago

Thanks, DO share what you make with it

randofo 5 years ago

Interesting. I never thought to make a mold using hot glue.

Malicity 5 years ago

Fantastic idea! I have a massive amount of glue sticks, as I bought a case, in a moment of madness...and I so don't have a load of money! This is such a great option; thanks!

Just so you know, a friend of mine is a Master in casting, and even so, her casts will come out with flaws, such as little "positives", as well as the occasional hole. She makes very intricate pieces, an uses dental tools to remove excess, whereas I hit it with a wire brush...my clients aren't as discerning!

With the holes, it's easy enough, until you get your mix/pour down, to fill with a bit of plaster, before painting. I voted for you. Best wishes.

Amit_Jain 5 years ago

Thanks, Please share your friend's work. It could be inspiration for my next project