Subproject: Knight

Sub project: Knight


I decided to begin with the most intricate, and thus the most difficult piece to create as all of the other pieces are easily machines in the lathe.


I started out with designing the knight in Blender. It's a professional grade 3D modeling/animation application available for Windows, Mac, and Linux. Based on a generic image for a knight I came up with this design:



From this I'm able to generate the gCode used by my CNC router. I'm using EMC2 which is available for Ubuntu Linux to run my CNC machine:




I'm not going to go into detail on my CNC machine in this article, but may post an article on how I built it at another time. Here is the first rough pass from the CNC router which gave me the basic shapes. Because This will become the base for the mold, I need to do the piece in halves.

rough cut

 After a final pass with the CNC router and some rough sanding, My mold
model is almost ready for casting.
You can see the two halves held
together here so that I can get a sense of symmetry:


Here is the final part. I'm ready to cast it in aluminium which will have to wait for the weekend.
I put a coat of clear gloss to seal it up and prevent cracking. It has to last long enough to make four knights.


Ive now made the sand cast mold from the wooden template:

 Coat the template with a bit of talc, then pack the sand around the first half of the template. I use Jupiter Blend casting sand.
 Once I;ve done both halves, I remove the wooden template and cut a fill hole with a brass tube to the top of the mold with a 'gate' to the chess piece cavity. This will allow the aluminum to flow into the mold. You can tell from the photo, but I also used a wooden BBQ skewer to make a vent hole at the top of the mold so that air and gases can escape and not create air bubbles in the pour. 



Now I fire up my furnace and melt my scrap the same as I did in This Article:

   

After the metal is poured and cooled, I've taken the casting out of the mold and am ready to cut off the excess. It is a very rough casting and will need to be sanded, machined and polished.


Here is the finished piece. Not quite polished as much as I want but for now it will do. Now to make three more...


Comments

Hi,
What type and size is your crucible?
 
(your Captcha is easy to read, but could still use a recycle button. Some characters truly are unreadable :-) )

By flink (not verified)

Sorry about the Captcha, I'll look into that.

 

The crucible I use is from Budgetcastingsupply.com  It the type "A" Silicon Graphite one.

By dave

Add new comment

Filtered HTML

  • Web page addresses and e-mail addresses turn into links automatically.
  • Allowed HTML tags: <a> <em> <strong> <cite> <blockquote> <code> <ul> <ol> <li> <dl> <dt> <dd>
  • Lines and paragraphs break automatically.

Plain text

  • No HTML tags allowed.
  • Web page addresses and e-mail addresses turn into links automatically.
  • Lines and paragraphs break automatically.
CAPTCHA
This question is for testing whether you are a human visitor and to prevent automated spam submissions.
Image CAPTCHA
Enter the characters shown in the image.
secret-login