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Picture of Foundry Sand Casting Ramming Tool
This is sort of  part 3 for my two foundry  instructables. In this short ible I will show how I made a ramming tool for my sand casting future projects. The idea is very simple and done in a few steps.
Links to my first two ibles on how to make the foundry
:

Mini Charcoal Furnace
My Second Aluminium Foundry




 
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Step 1: Making the Ramming Pattern

Picture of Making the Ramming Pattern
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The pattern I made  was from a wooden stairs banister I had in my shed coverd with dust for a few years. It's a perfect size for a ramming tool and has a decorative feature.
After cutting to a suitable size I beveled one edge so it will fit nicely into the flask corners.
A bit of fine sanding and I got a good wood pattern ready.

Step 2: The Flask

Picture of The Flask
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I made a new wooden flask larger then my old one in order to fit my pattern.  The flask is made of 2 parts, top is the Cope and bottom is the Drag. On the side I have wood drilled to keep both parts aligned together. The pattern is placed in the Drag part. The Drag is placed upside down at this stage.

Step 3: Getting the mold ready

Picture of Getting the mold ready
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First I start placing the Petroband over the pattern ramming it with a block of timber and this is where the future ramming tool will come into use. After the drag was coverd all the way up I turned it back up and notched around the pattern half way down smoothing it with a spoon, nail and my trusty finger.
Then a bit of parting powder on top to prevent the drag petrobond sticking to the cope
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Step 4: Nerve wracking part

Picture of Nerve wracking part
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This is the nerve wracking part separating the cope from the drag and removing the pattern out of the Petrobond.
I removed very slow and gently both parts and the pattern .....SUCCESS , a beautiful mold was created. I made the pouring hole with a metal pipe, another way to do it is by placing a cone shape piece of timber into the cope while ramming  the sand and then remove it. On the pattern end part I made a small vent hole (a bit too small).
Then again very slowly I closed the flask and placed a clamp to hold it tight
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Step 5: My new Aluminum Ramming Tool

This was the hardest part for me, WAITING.  I poured the molten aluminum into the flask and the left overs into the slim ingot tray that I made. I let it cool down and then I opened it all exicited to see a beautiful new tool to add to my collection. My new Aluminum Sand Rammer.
I cut off the extra metal from the pouring spout and from the vent hole. After I gave it a light grinding and cleaning and it is ready for use.
Mozenrath1 year ago
Hey, this is a great tutorial. Thank you very much!

I do have some tips for people who want to cast some detailed parts using petrobond. I'm by no means an expert but my skills in sand casting have recently improved and I thought I'd share.

- First of all, use a screen to sift the sand while covering the pattern with the sand. A typical kitchen strainer works great for this. Not only I tried casting for ages without doing this but got really poor results. The difference in casting quality between a sifted cast and a non-sifted cast is night and day. It cut down on imperfections by about 95% I'd say. This really doesn't matter much for this kind of instructable(a large tool), but if you're trying to quickly cast something small, you have to sift the sand. No other way around it.

- When ramming the sand, ram it HARD!

- Aside from professional-grade stuff, chalk makes the best parting dust in my opinion. Many people use talcum powder and it usually works fine, but chalk works even better because it doesn't absorb water or oil. You can get little bottles of finely powdered chalk from virtually any hardware store.

- Cover any part of the mold that becomes exposed to the air at any point with parting dust. This helps prevent parts of the petrobond sand from crumbling off and contaminating the negative impression in the mold.

- Once you have taken out the pattern from the mold, use an air duster can to blow away any little rogue specs of sand that can ruin the mold.

- This isn't all that necessary, but heat treating the important part of the mold with a torch for a few seconds can help the negative pattern stay more solid. Again, not all that important, but it can make a difference if some imperfection in the mold breaks off when the molten metal rushes through.

- For small parts, removal of the pattern can be extremely difficult without screwing up parts of the mold. If you have a pattern that's not too delicate, the best way to remove it from the mold is to use cyanoacrylate glue to glue a little piece of wooden dowel to the exposed part of the pattern. As soon as the cyano dries, pull on the dowel to pull out the pattern.
rimar20004 years ago
Excellent!
NutandBolt (author)  rimar20004 years ago
Thank you :-)
ironsmiter4 years ago
Can't wait for "part 4" :-) Consider me subscribed.

Bonus... you have a spare wooden ramming tool for when you get a visiting sandcrab that wants to join you in your work.


On a Halloween note, "first look after cleaning the dirt off" sure does look like the beginnings of an awesome sci-fi blaster gun.
Very Pew-Pew!
NutandBolt (author)  ironsmiter4 years ago
Thanks for your comment, it does actually look like some sci-fi gun, Thats a cool idea to make some blaster pattern and cast it from aluminum.
Kryptonite4 years ago
Nice, I'm always amazed at this because the end result always turns out the same as the beginning.

Obviously that comes standard, but some how always impresses me. :D