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Here is a pic of the bridge when I first built it around 1994-95, maybe earlier, don't remember. It was on the Cedar Gken Nail Road. (All the people were made out of horsenails). The bridge was not used on the second layout which burnt in the forest fires of 2004, but it survived. The forest fires caused it to rust to that patina and that is how it will always stay. It is a fully functional pin truss bridge, built just like the real one. Many live steam engines have run thru it.
 

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Bob,

Thanks for taking the time to post the photos. The Lizard buckle is cool, especially because of how it was created.

Wood is my prefered medium but that bridge really has me thinking about working more in metal !

David
 

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No, it takes you to a site named like the link is named...

Here at printedsolid.com, through the use of a mix of dark magic and science, we have discovered the secret to turn plastic into metal. That’s right. We’re modern day alchemists.

Alright, maybe that’s a bit of an exaggeration.

We have been experimenting with using 3D printed parts for investment casting. Investment casting is not new. It is a manufacturing process where a part or artistic piece is made in a soft/low melting temperature (wax and foam are commonly used). That piece is then coated in a ceramic slurry (kind of like plaster of paris but with other stuff added in to make it stronger and more heat resistant). The slurry is cured until it is hard and strong. The original part is then burned out or melted out. Now there is a hollow cavity in the shape of the part. Molten metal is poured in and you ‘magically’ have a copy of your part in metal. This process allows for reproduction of very fine detail.

So, the process is not new. However, 3D printing is (relatively) new. It turns out that some common 3D printing materials (PLA in particular) also work really well as originals for investment casting.

We have partnered with a local casting guru with the goal of eventually offering lost PLA casting as a service. We will offer three different options.

1) Send us your idea and we design, print, and cast

2) Send us your stl file and we print and cast.

3) Send us your 3D printed PLA part and we cast. The ‘Maker’s Special’.

Some of you may be reading this and thinking, ‘why would I have someone cast for me when I can do all this myself’. For you makers that are not afraid of molten metal (I have to admit that I am) we will be starting up a blog with the lessons we learn as we perfect this art.
 

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I had created a 3D model driver for a coronation class 4-6-2. About 3 inches across. I put it on Shapeways and was quoted $98 for a steel print! $98 for one wheel? No thanks, shapeways.
 

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Thanks Pete, those are really nice. Truth be told, even at 1:32 it wouldn't make a single curve on my layout and would be a static model so 3D printing will suffice. I am just finishing up a standard scale Clyde Puffer for the layout and the pool! I'm trying to decide if I want water in a small lake or wrap it in plastic and press it into a painted concrete lake. When that's done it may be next.
 

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That's right Scott.
Wood Gadget Electronic device Font Circle

I had to do some slight modifications to the prints to cast them. Sand Casting is the way to go on some of them because there is no need for a burn out copy and the nice thing is:
Wood Font Circle Gas Metal

With sand casting you can use the same print over and over again. If you've looked at the price of wax resin you can easily calculate the cost difference between burn out blanks and reusuable blanks. Even the sand is reusuable.
 

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Moldmax 40 rubber to make reusable molds for whitemetal casting. Delft clay is good for larger item's and other metals ie brass, aluminium, bronze. With greensand or delft clay it needs to be rolled or broken up to re-use. Plus any burnt materials removed and discarded.
 

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Moldmax 40 rubber to make reusable molds for whitemetal casting. Delft clay is good for larger item's and other metals ie brass, aluminium, bronze. With greensand or delft clay it needs to be rolled or broken up to re-use. Plus any burnt materials removed and discarded.
I've used the polybond to do low temp castings.
Coin Currency Money Font Silver

Sand casted: Rt wheel is tin 550 F and the left is fields metal 175 F. It's also used for casting jewelry. I'm using the extra fine, like the jewelers do. You can use a sieve to break it up, or your hands, and the burnt stuff is minor, and a little bit mixed in with the good stuff is okay. The trick is packing it tight. It should be rock hard before you're ready to move to the second half or cast.
 
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