Trains.com

Subscriber & Member Login

Login, or register today to interact in our online community, comment on articles, receive our newsletter, manage your account online and more!

Making latex rubber molds

29253 views
37 replies
1 rating 2 rating 3 rating 4 rating 5 rating
  • Member since
    August 2008
  • 357 posts
Posted by EM-1 on Wednesday, February 10, 2010 12:49 AM

I was just looking at the Micro Mark cataogue, which shows a number of different one and two part molding rubber compounds.  The current catalogue pages 26 and 27 show a considerable number of items for making molds and castings, while on page 76 they list a Mold Maker Liquid Latex rubber, a single component item, 32 ounces for 22.85.

An article on molding parts I just scanned into a JPEG file show the author spraying the master with spray paint to seal the surface and make striping it from the mold easier.

It's been a while since I read articles in MRR and RMC about making rock molds, but I seem to recal the rocks may have been sprayed with water or "Wet Water" (water with a couple drops of liquid soap added.

If you get the liquid rubber, just get a couple random rocks of little interest and expirement.

  • Member since
    December 2005
  • From: Central Florida
  • 45 posts
Posted by Bob W on Tuesday, February 9, 2010 6:40 PM
Mold Builder

Mold Builder

Castin’ Craft® Mold Builder is ideal for making molds to cast Clear Polyester Resin or epoxy, plaster, candle wax and even concrete! This liquid latex rubber product brushes-on almost anything,

 

 

Bob W [FL]

If it ain't broke.... Fix it till it is !

  • Member since
    July 2006
  • From: Central Vermont
  • 4,565 posts
Posted by cowman on Tuesday, February 9, 2010 6:14 PM

Brent,

The only brand I know of is Woodland Scenics "Latex Rubber" it's number is C1204.  Since I have no Michaels or the like around I am not sure what you should look for.  Try asking for Latex Rubber.  If that doesn't work ask your LHS to add it to his next order.  They are usually happy to do this, they can special order, but that usually costs more and for that you'd  probably do better to place an order with a mailorder or online store.

Good luck,

  • Member since
    July 2006
  • From: Pittsburgh, PA
  • 1,796 posts
Posted by JoeinPA on Tuesday, February 9, 2010 4:59 PM

 Mark:

The raw plaster of the master will present a problem in that it will adhere strongly to the rubber in places with the result that you will risk either tearing the rubber or damaging the master when you try to remove the mold. I found that sealing the plaster master a couple of coats of Minwax Polyacrylic varnish gave a nice surface and the rubber molds separated nicely. I sprayed the finished mold with a little wet water (water plus a drop or 2 of liquid dish detergent) before adding the plaster and the finished castings separated nicely.

Joe

  • Member since
    December 2009
  • 159 posts
Posted by mkepler954 on Tuesday, February 9, 2010 2:32 PM

The pieces I have now are brand new raw plaster.  They have never been painted or stained.  I didn't know if the latex rubber would react with the plaster, i.e. soften it which would destroy much of the details. 

  • Member since
    July 2006
  • From: 4610 Metre's North of the Fortyninth on the left coast of Canada
  • 9,352 posts
Posted by BATMAN on Tuesday, February 9, 2010 10:24 AM

 This is a timely and interesting subject for me as I am contemplating trying to mold some interesting rocks my daughter collected for me. Can anyone please give me a brand name or two. Also is it available at Michaels? My two nearest hobby shops don't carry anything like this. As always thanks.Smile

 

                                                              Brent

Brent

"All of the world's problems are the result of the difference between how we think and how the world works."

  • Member since
    January 2006
  • From: Austell, GA
  • 42 posts
Posted by randythawkins on Tuesday, February 9, 2010 9:53 AM

cowman

 

 One thing I will suggest is that after a couple of layers of latex, cover a layer, while still wet, with some fiberglass tape (wallboard tape), then give it another layer or two. It makes the mold much stronger and it will last a lot longer. Good luck,

 

 

I have used used dryer sheets.  Due to the finer mesh they are a little more difficult to get soaked with the latex but seem to have resulted in comparable results. I have used my 'dryer sheets supported molds' many times without a problem.

Randy
  • Member since
    July 2006
  • From: Central Vermont
  • 4,565 posts
Posted by cowman on Tuesday, February 9, 2010 8:53 AM

It's been a while since I made a mold, but I have several rocks awaiting a through cleaning, then I will make some molds. I would think as long as they are good and clean that you should have no problems. Don't know if it will take a little paint off your pieces or not. I have a retaining wall I plan to duplicate also. One thing I will suggest is that after a couple of layers of latex, cover a layer, while still wet, with some fiberglass tape (wallboard tape), then give it another layer or two. It makes the mold much stronger and it will last a lot longer. Good luck,
  • Member since
    December 2009
  • 159 posts
Making latex rubber molds
Posted by mkepler954 on Monday, February 8, 2010 8:57 PM

I bought several plaster portals and stone walls from Woodland Scenics and intend to use them as masters for making latex rubber molds.  Is there any special prep I must do to the plaster portals/walls before I apply the latex rubber?

Subscriber & Member Login

Login, or register today to interact in our online community, comment on articles, receive our newsletter, manage your account online and more!

Users Online

There are no community member online

Search the Community

ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT
Model Railroader Newsletter See all
Sign up for our FREE e-newsletter and get model railroad news in your inbox!