Asheville Makers Wiki

You've loaded an old revision of the document! If you save it, you will create a new version with this data.

====== Bird Letter Opener 12/2016 ======
A friend asked me if I could forge her a letter opener shaped like a bird, I thought about it and decided that casting one would be better. Its aluminum so the blade will wear faster, but its a letter opener not a butcher knife so it will be OK as long as she doesn't open all the junk mail.

I started by creating a model in Fusion 360
pic here
Then bought some castable wax filament for the 3D printer and printed the model. This process took a LONG time to get the setting close enough to work for me.
pic here
Then I sanded and cleaned up the print and tried to make a plaster of paris mold. Making the mold worked fine, but melting / burning the wax out caused it to fail...
pic here
So I printed another one, sanded and cleaned it up, then with the help of Bob Sinclair, we created an investment mold and baked the wax out for 12 hours in his oven...
pic here
Then melted and poured the aluminum...
pic here
The result isnt what I hoped for, the surface texture should be smooth. 
pic here
I think this happened because my sprue wasn't long enough and the aluminum in the resivoir froze before the bird cooled. Then as the bird cooled it was able to shrink and pull away from the mold surface.
But sometimes we carry on and I sanded and dremmeled the casting until I got a descent finish. I didnt want to remove too much material so I left some of the pitting in the body. I ground the tail / blade at a slight angle so it looks like the vanes of a feather.
pic here
Over all I am happy with the end result. I am going to experiment with some lost foam casting of the same bird as an alternate method. I'll post those results later.

Please fill all the letters into the box to prove you're human. W Z Q L H Please keep this field empty:

Edit summary

Note: By editing this page you agree to license your content under the following license: CC Attribution-Noncommercial-Share Alike 3.0 Unported

Asheville Makers Wiki

Site Tools

Page Tools