Girder Bridge
Cost for RTV to make mold: $7
Cost for each 12” section of Resin: $2
Time to make master: 4 hours, including making rivets on cardstock, gluing coffee stir sticks and sealing
Time to make resin copies: about 4 minutes to mix and pour and wait time of 1 hour to cure
Directions: use spray paint of color of bridge you want to spray in mold. Acts as mold release and paint embeds into the casting. Attach girder to wood with wire nails;
Mistake: used what I thought was smooth wood but grain pattern came out in master and castings. To correct the mistake, simply made small batch of RTV and skimmed over the surface to fill in the wood grain impressions. RTV sticks to RTV so RTV repairs can only be made with RTV as nothing on earth sticks to dried RTV.
Note the wood grain; I later sanded this casting down and corrected the RTV mold
2 castings in place (2 feet)
Curly spokes (handmade)
Started with Bachmann wheel casting (casting easier to carve than metal so master is casting), scales to 20 inches in 7/8. Used drill and needle files to make curlies. Didn’t use template. Simply freehand drew curlies on the wheel.
Tom Trigg
the hound might break the mold :-)
FJ and G wrote: the hound might break the mold :-)
Hey! That is the Boss BB your speaking about!!!!!
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