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    • April 16, 2017 8:00 PM EDT
      • Ohio
         
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      Casting metals

       Who has experience in casting parts and stuff with metal like pewter lead and such?. I know of one on here ...Devon.... I have 15 years of experience with casting lead bullets for muzzle loading Civil war firearms, so I have the melting pots for such stuff. These however are cast in bullet mold blocks. Unlike bullets Ya have to make molds for what ya want to cast. This is where I'm getting confused somewhat on the molding material type. I have read that you use high temp RTV and some say silicone rubber molds?. the latter sound like it would melt or burn. I like the idea of doing metal casting as it would last longer and maybe get better details and the possibilities are somewhat endless on what ya can make. So any input, ideas, or suggestions would be welcomed. Thanks for all the help... Travis.

    • April 16, 2017 8:23 PM EDT
      • Sparta, TN
         
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      This may be an area of personal preference. I see RTVs advertised as suitable for "high-temp" applications, such as pot metal. However, I suspect the traditional process is vulcanized rubber
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    • April 16, 2017 9:41 PM EDT
      • Farmington, New Mexico
         
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      High temp RTV is the way to go..   It will handle pewter, and other similar low temp metals.  The right RTV is designed for this use, and will produce high detailed parts if you do it right.  I have cast numerous parts and made various molds for truck side frames, bolsters and switch parts.

      As you can see, there is a need for large volume spurs to handle the shrinkage of the pewter.  Also make sure that the master and molds allow for good flow to all areas.  On this mold I heat it ( the mold) before I pour.

       

      EDIT:  Also, check with you metal supplier as to the recommended pouring temp.  Also High temp RTV is defiantly less flexible and a harder rubber.  It will last near forever if it is used for Resin casting, and the same mold can be used for both metal and resin.

      Edit:  John C. would be the local Guru on spin casting and Vulcanized rubber molds.

      This post was edited by Dave Taylor at April 17, 2017 1:45 AM EDT
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    • April 18, 2017 2:42 AM EDT
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      Dave, 

        What brand of RTV mold did you use in he above pics?

    • April 18, 2017 9:43 AM EDT
      • Farmington, New Mexico
         
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      @Travis  I Used the stuff from AeroMarine Products...   The High temp stuff has changed from the time that I made those molds...  Call the company.  They have great customer service, and the ladies that answers the phone knows what she is talking about, not just a answer girl.  Tell her what you want to do, and make sure that you tell her it is for metal casting.

       

      1-877-342-8860  AeroMarine Products...  BTW the 55gal drums are really expensive!

       

      https://www.aeromarineproducts.com

       

       

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    • April 18, 2017 11:55 PM EDT
      • Post Falls, Idaho
         
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      Travis. RTV is Silicone rubber. And there is a wide variety of it. Trust Dave T. He is who I went to to understand the process. Now I have not used the High Temp RTV yet. I need to get some. But the standard RTV silicone mold rubber will work for low temp metals. It does not melt it and I have used it with some success. What happens though it seems is that it erodes or otherwise weakens the regular RTV. While it doesn't melt it loses detail and eventually tore on me. For one off parts or a few parts the regular RTV would work and is much cheaper than the high temp stuff. But if you want reusability then the High Temp stuff I would assume is the way to go. Trust Dave.

       

      Oh and I don't know if Dave does this or not but I use talc in my molds for pouring metal. I dusted the mold with a light coat and then tapped them clean so only a fine layer was left. seemed to help. Also the warmer my mold got the better.

       

      Dave, what temp do you heat your molds too before pouring? Seems to me coming very close to or even exceeding the pour temp of the metal would be good. then let the whole thing cool together. But I am wondering what you do.

       

       

      This post was edited by Devon Sinsley at April 19, 2017 4:11 AM EDT
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    • April 19, 2017 12:13 AM EDT
      • Port Orchard, Washington
         
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      Anyone every melt down aluminum cans and cast metal parts in aluminum? I've been thinking that would be a good way to make track detail parts.
    • April 19, 2017 10:23 AM EDT
      • Farmington, New Mexico
         
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      When casting the side frames,  I generally set my oven to 350-375 degrees,  and place the Talced molds for a few minutes, opened in the oven, and then take a temp reading with my infrared thermometer to assure that its at least 300 degrees on the mold surface, then assemble and pour.

       

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    • April 19, 2017 12:35 PM EDT
      • Vail, Az
         
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      Oooooh I'm a guru?!!!!!!

      Flattery my son will get you .....

       

      Only 20 years casting silver and gold with the spin caster, but all of it was investment casting and our vulcanized molds were only filled with wax. I cut all our molds after I objected to using some molds my bosses' buddy butchered...

      Then another 6 years with a vacuum caster, still all flasks were investment castings, which you need for; brass, bronze and other metals due to temperature burning up your rubber.

      About the only tip I gave Devon was to use an old nylon stocking to hold a 'golf' ball of talc, secured with a string or rubber band, just tap against the object and the dust is left behind, blow off excess. Too much can pit the surface.

       

      John C

    • April 19, 2017 3:06 PM EDT
      • Paraguay
         
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      Craig Townsend said:
      Anyone every melt down aluminum cans and cast metal parts in aluminum? I've been thinking that would be a good way to make track detail parts.

       

      our local hillbillies melt down cans for dagger-grips.

      open fire, founded iron pots (you might know them as "Dutch ovens") and forms/molds from the local clay.

      details are generally made with files, chisels and hammers. - so not really modeling quality...

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      My Chaosplace ->  

    • April 19, 2017 10:43 PM EDT
      • Post Falls, Idaho
         
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      Craig Townsend said:
      Anyone every melt down aluminum cans and cast metal parts in aluminum? I've been thinking that would be a good way to make track detail parts.

      Way beyond the temp range of RTV. need to use another mold materiel like sand or what ever is used in lost wax casting. Aluminum is a higher melt metal

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    • April 21, 2017 8:32 AM EDT
      • Southern Illinois
         
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      Son in law has exposed me to a whole new sub hobby of melting beer cans.  Gives another reason for consumption.

      He's very resourceful and enjoys sharing his hobbies.  You can investigate on youtube.

      This post was edited by Ric Golding at April 21, 2017 8:33 AM EDT
    • April 21, 2017 8:47 AM EDT
      • Pittsburgh, Pennsylvania
         
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      I already have a reason for consumption.

       

       

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    • April 23, 2017 7:42 PM EDT
      • Ohio
         
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      nice looking standing seam roof! how did you make the panels?

    • April 24, 2017 8:11 PM EDT
      • Pittsburgh, Pennsylvania
         
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      Travis Dague said:

      nice looking standing seam roof! how did you make the panels?

      Thank you. Like this;

      http://largescalecentral.com/forums/topic/20961/drink-can-standing-seam-metal-roof

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