How to make a simple silicone mold from an existing pattern

      How to make a simple silicone mold from an existing pattern

      This is a pictorial of how the mold was created.

      The pattern was
      prepped using techniques I've learned over the years doing automotive
      body work, surf board building, bronze casting and custom car
      painting. What I've discovered is “you get what you put into it”
      so the pattern had to be perfect. Surface smooth and free from and
      bumps, pin holes, paint drips, sand paper marks and even finger
      prints.

      120612-mold-making--1.jpg

      Materials need to successfully make a silicone mold

      1. Tin or platinum based silicone parts A and B
      2. Thixotrophic additive (thickening agent)
      3. Brushes
      4. Icing knife (for cake decoration)
      5. putty knife or a 5 in 1 painter's knife
      6. Razor knife and extra blades
      7. Plaster bandages
      8. Hydrocal or plaster of paris
      9. Assorted Buckets & Containers
      10. Newspaper
      11. Latex gloves
      12. A few harsh words and lots of clean water
      120612-mold-making--1a.jpg

      With the pattern
      prepped and ready for it's fist coat of silicone wipe down the
      surface with rubbing alcohol to remove any oils or other contaminants
      present. Mix up a batch of silicon and brush onto the surface on the
      pattern. At this point in the process, don't worry about brush
      strokes as the silicone will flow out into a uniform skin coat.
      Allow this first coat to setup to the point of no tack. Do not let
      the coat cure. Follow the manufacturer's instructions on mixing
      ratios cure times.

      120612-mold-making--2.jpg

      After no tack has
      been achieved it is time for the second coat. Depending on the type
      of silicone purchased you may or may not have to use Thixotrophic
      additive to the mixture. What this material does for you is it acts
      like a thickening agent. What you want is a mix that is the
      consistency of peanut butter. Using the Icing knife, carefully and
      evenly spread the thickened material unto the skin coat. Take care
      not to drag the knife into the skin coat.

      120612-mold-making--3.jpg

      Repeat this process
      until you have a buildup of at least 1 to 1.5 cm. On the last coat
      you'll want to create mold keys. This can easily be done by using 2
      liter soda bottle caps, filling the caps with silicone and placing
      them onto the uncured final coat. What you are trying to accomplish
      here are keys to hold the jacket or ​mother mold in place.

      120612-mold-making--4.jpg

      On this particular mold I was designing it to have a two part
      mother mold. So I positioned the keys as needed to achieve this.

      120612-mold-making--5.jpg

      Prepping for the
      plaster mother mold. Layout all the materials you will need for this
      process. Cut the bandage in 6 inch strips. Make sure to cut more than
      you'll need because plaster cures and will not wait for you. It is
      better to have material left over rather than having to redo the
      mother mold because you didn't want to waste materials. Plaster
      bandages have to be applied all at the same time building up the
      thickness of the mold. Once the plaster has set you will be unable to
      add more thickness, The material will not adhere leaving you with a
      failed mother mold. In this process I mix cols water with the dry
      powder plaster at a ratio of 5 parts water to 1 part plaster. It is
      better to use a material like hydrocal or even ultracal plaster. It
      gives the plaster bandages extra strength. A stronger mother mold
      gives you more cycles of use.

      120612-mold-making--6.jpg

      With the first
      section of plaster bandages cured it is time to move onto the main
      section of the mold. Repeat what you did on the first part. Make sure
      when applying the plaster bandages to read the manufacturers
      directions on application.

      120612-mold-making--7.jpg

      Having finished the second part of the mother mold let it cure for a day or so before
      removing it.

      120612-mold-making--8.jpg

      Using the painter's
      knife carefully pry off the smallest part of the mold. This may take
      you a bit of time. If the bandages were properly applied the plaster
      with take on the surface of the silicone. This simply means it will
      be a real pain in you back side to remove the mother mold for the
      first time without damaging it. Take you time. If you do screw up,
      simply reapply a new entire section of the plaster bandages.

      120612-mold-making--9.jpg

      Repeat on the main section of the mother mold.

      120612-mold-making--10.jpg

      With the two sections successfully removed from the silicone mold it is now time
      to spit the silicone.

      120612-mold-making--11.jpg

      Using the razor
      knife cut up the back of the silicone on the bulk of the pattern. You
      are doing this so you can easily separate the mold from whatever it
      is being used for. After the cut has been made, start pealing up the
      mold. Start at the back and carefully peel it up. As air gets between
      the mold and the pattern it will loose it adhesion to the pattern.
      Some people use compressed air to help in the demolding process.

      120612-mold-making--12.jpg

      Once you have successfully separated the mold from it's pattern It is now time to
      place it back in the mother mold. See on the top of the image frame
      where I cut the mold??

      120612-mold-making--13.jpg

      First pull. Prepping for the first shell. I use masking tape of really any type od tape to
      wrap and hold the mother molds together. I place strips of duct tape
      around the edge of the mold to protect the plaster. Once all the
      peop id done I coat the interior of the new mold woth gelcoat. I
      allow it enough time to start setting before I lay in the first coat
      of glass matte. The matte is cut in 5 x 15cm strips “BEFORE” I
      mix up the polyester resin.

      120612-mold-making--14.jpg

      First coat done, get ready for number two.

      120612-mold-making--15.jpg

      Second layer of FRP done. Let it setup so there is no tack. Depanding on the
      resin to catalyst ratio you use this can be 4 to 24 hours.

      120612-mold-making--16.jpg

      I use a body grinder to trim the edges of the shell. Some people use a razor knife or even
      sand down the edges after the shell is pulled from the mold. This is
      all up to you. As there is no “right” way to do it. These are
      just the basics. You will learn your own techniques the more you do this.

      120612-mold-making--17.jpg

      Since all LiveWearYu's are half masks grinding the edges down while in the mold
      saves time after the shell has been removed.

      120612-mold-making--18.jpg

      If you did your pattern right and know how the properly layup FRP into a mold the
      surface should be fairly flawless. Sanding and painting should not be
      a big deal. Remember to allow the FRP to “completely” cure out
      “before” applying and type of paint. However you can fill and
      sand any inconsistencies in the shell with catalyzed automotive body filler.

      120612-mold-making--19.jpg

      Once cured go ahead and finish off the shell. Get it ready for flesh. Make the magic
      happen. My prep work is some of the best I've ever seen. Free on
      sanding marks, pin holes, drips and otherwise sloppy and rushed
      finishing. There is no excuse for shotty work if you plan to do get
      into the making business.

      Well I hope this short tutorial helps those interested in making basic silicone molds
      for kigurumi mask making. As I said in the beginning. I've used these
      methods and techniques for a few years. There are no short cuts or
      ways to do it in a more cost effective manner.

      Basic costs of a mold of this size.

      Basic tools $35 USD
      Silicone $175 USD
      Plaster Bandages $ 45 USD
      Body Grinder $85-125 USD
      Plaster $25 USD
      Newpaper Free
      Bottlecaps Free
      Sundries $25

      Patterns costs are all over the map. I can basically say the you can spend $75 on clay
      and plastic. Another $50 on basic tools, plastic, turntables and
      such. All this portion really takes is talent and the will to finish the project.

      Time involved to get to a finished shell?? 4 weeks to 5 years depending on your
      determination to complete the project. Remember that 95% of the
      people that start a mask never finish it.

      So when you look at the price tag on a finished mask think about the time it took the
      maker to complete it. Not just the time to actually turn it around
      from a shell, but all the R&D that went into the production of
      the finished piece. We don't like to think about the fact the making
      these jewels are a business but they are. Successful makers have a
      business plan, charge profit, pay taxes and put everything they can
      back into the development of new models and processes. It is very
      exciting to be a maker in these times because of all the new and cool
      processes being used these days.



      Great tutorial Cici.

      I'd just like to mention one thing about undercuts, since your pattern did not have ears.

      If a pattern has areas which might get caught in the mother mold, like behind ears, or a really sharp chin, it's useful to make sure the silicone fills in areas like that before you apply the plaster for the mother mold.

      It makes removing the mother mold easier, without having to make the mother mold in two pieces.

      Kiki
      First , thanks so much, Senpai! It would help me a lot on my kigu future if everything go well...
      For now I don't get 100% of it but I think I can do it with care o3o
      Maybe not the first time , but it's possible, right?
      Great work!!
      ( ^w^)/ hey~

      Post was edited 1 time, last by “Takami” ().

      Miss Kiki wrote:

      Great tutorial Cici.

      I'd just like to mention one thing about undercuts, since your pattern did not have ears.

      If a pattern has areas which might get caught in the mother mold, like behind ears, or a really sharp chin, it's useful to make sure the silicone fills in areas like that before you apply the plaster for the mother mold.

      It makes removing the mother mold easier, without having to make the mother mold in two pieces.

      Kiki


      Undercuts have never been a problem much less two, three and even four piece mother molds here at the studio. Not a bad tip for beginners though kiki. Here we never prep patterns with ears. Simple enough reasons, one is we have so many different options of ears to offer our buyers, and two, we've found that attached ears actually give us inferior layups using the types of matte and resins the studio employs.

      Takami wrote:

      First , thanks so much, Senpai! It would help me a lot on my kigu future if everything go well...
      For now I don't get 100% of it but I think I can do it with care o3o
      Maybe not the first time , but it's possible, right?
      Great work!!



      Remember kouhai, this process was used by the studio three years ago. It is solid and easy to do for beginners. You just take your time making sure the pattern is perfect "BEFORE" you give it a bath in silicone. Since then we've applied completely different techniques to replicate semi custom shells. Mold making takes on a whole different meaning when you advance from half masks to full enclosures.

      For now though, stiff to this process as it will serve you well ^^//
      And finally the time for me to do it arrived, I not sure about base perfection but I'm totally new for it, It's funny the mess I'm doing here xD
      One thing is that I don't have this productthat make the silicone thicker. .. since it gonna take some time to arrive if I order it, how bad is the idea about doing layers of silicone and towel paper ? Should I be patient instead? XD
      ( ^w^)/ hey~

      Wait for the thickening agent to arrive. It will be well worth it.
      Using paper towels as an alternative is a novel idea but let's stick to what works.

      Here is a good reference video on the subject



      A suggestion is while you are waiting for the agent to arrive get that pattern perfect. Remember if the pattern is perfect the mold and cast will be as well.
      A little more time to prefect gives you time to work on the finishes and wigs rather than sanding out the same imperfection in the cast every time you cast it.
      Thanks for the video!
      Well the two main problems here is that ... I'm looking for this thickening agent so idk how much gonna take heheh /runs/
      And about perfection, I think the way I let it I could not work more unless take out a big part an re do it all... (but was my fault, I should have worked in the daylight actually ...=3= )
      And that I already started using the silicone on the first steps to see how it would go :v
      Strange that after a day some small parts are sticky/uncured in, like, a day, maybe I haven't mixed it right? well I can wait util the agent arrives :B
      ( ^w^)/ hey~