In this instruction I am going to show you two different ways of casting aluminum, telling you what the advantages and disadvantages of these methods are and what you need to know to make you own one. I am not good at writing English, but I try to do my best and I apologize for mistakes.
Step 1: Selecting the Method You Want to Use
The first method I introducing is the lost foam casting, it’s the easy way of doing it. The only advantage of this method is that you don’t have that much effort to make the Styrofoam template. It is quickly done and you only need to cut it out and glue it together. One of the biggest disadvantage in this method is the surface of the sward needs a lot of after work and cleaning. Secondly during the cast you breathe in a lot of toxic fumes and your clothes stink pretty badly. Furthermore in the caste you will see trapped air, which can ruin the cast completely or let it look bad. As you can see in the picture with the Minecraft pickaxe.
The second method is the green sand casting, it takes a bit more effort but the result you get is much better. This is the method I prefer and always use. The two big disadvantages are that it takes a long time to make the wooden template and prepare the casting mold. The big advantage of this is, that the surface cleaning and the polishing are much easier compared to the lost foam casting. Furthermore you get a much better result without trapped air bubbles.
Step 2: Lost Foam Casting Materials
3. Bucket big enougth to fit the template
4. Play sand
5. Aluminum scraps like heat sinks
How especially you do the lost foam casting you can see in this video of Grant Thompson - “The King of Random” and how he did the lost foam casting. I personally don’t really use this method, i only used it for my first tries and then quickly changed to the green sand casting that’s why I don’t go deep into the lost foam casting.
Step 3: The Green Sand Casting 1/3 Prepare the Wood
What do you need for this?
- poplar plywood 5mm
- wood glue
- round wood 4 mm
- Sanding paper
- wood spatula masse
To make the wooden template, just print out the paper template and cut it out. Then glue two pieces of the wood together so you have a 10mm thick plate. Now you need to glue the paper on the wood and just cut it out. After you cut them out just glue the single pieces together as shown in the video. At the end you finish with two separated half of the sword. Now to finish clamp them in a vice so they have a smooth edge now you need to drill a hole so the round wood can fit in with a bit of pressure. Then cut the round wood in length so it wouldn’t stick out of one side, then glue it to one of the half (both round woods need to be on one half).
Step 4: The Green Sand Casting 2/3 Prepare the Molde
What do you need to make the mold.
- Oil Sand
- Talk powder / carbon powder (to separate the two half’s)
- Sand Tin
- The previously done wooden template
What tools do you need?
- Hammer / wood piece to compress the Sand
- small pipe
- small stick
How to make the mold now? First you can watch the video, it’s just a time laps but you can see how it is done. First of all you need to take you template and cover it with the talk powder so the oil sand won’t stick to it. After you did this put the wooden side, that doesn’t have the round wood on it, flat on the table. Now lay the tin around it. Now you take the sieve and make a small layer of sieved Oil sand, which is necessary to catch all the details from the template. After a few centimeters you can press it on the template with the hand and a bit of pressure. Now you cover the rest with further oil sand and compress it with a hammer repeat that until that half of the tin is filled to the top. After you finished with this half turn it over and stick in the other half of the wooden template and then cover all of shown surface with further talk powder. Now you can put the second half of the tin on top of the first one. Now repeat the proses of the first half.
After you finished covering all, separate the two half’s slowly and with feeling so you don’t damage the two negatives. Now take the wooden template slowly out there and fix damaged sections of the mold. Now you just need to push through two holes in the top half of the mold with the small copper pipe. One hole is for the Al to flow in and the other for the air to get out. The penultimate thing to do is to make holes, at the top half of the mold, to release trapped air. You can do it by taking bamboo skewers and push them through the deepest places in the top mold.The last thing to do is to make a funnel at the filling hole. Then just put the two tins back together. !! Put them back together in the right way.!!
Step 5: The Green Sand Casting 3/3 Pouring the Aluminum
Basically what you need to do in this step is find some aluminum scrap and then melt it down in a of cut fire extinguisher. You can melt the aluminum in a flower pot and surrounded by charcoal. Now you need a hair dryer on the side and pump air into it. How you can build your own propane furnace you can see at The Mini Metal Foundry by The King of Random.
Step 6: Last But Not Least 4/3 the Cleaning
Grab some sand paper, files and a hex saw or an angle grinder and then start removing the excess metal that isn't needed and locks bad. After you removed all of that you can start filing the surface to a smooth finish. To finish of the project take some sand paper and clean of every surface to make it shine, to do so you start with a small numbered sand paper like 60 or 80 grid and work you way up to 1000 or 2000 grid. You then can finish the proses with some metal polish soap.
Till now I didn't use the sand paper because I have no time at the moment. I’m writing some exams in the school which are imported so I’m focusing on them. And I don’t have the motivation to do this because it takes a lot of time to bring it to a shiny surface.
All in all I hope I didn’t do so much grammatical and spelling mistakes but if there are some please let me now so I can change it.