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Yep- but how do you control the temperature?

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I had to think about this for a bit and I could be out to lunch so if anyone wants to step up please feel free. There’s no thermostat of any kind on the furnace so I guess don’t control the temperature at all. The propane burns at 3623F (1995C) and the aluminum melts at around 1240F (660C) all I have control over is the volume of heat going into the furnace. I’m not sure on the math needed to calculate the BTU of a burner but found a link that does it. (http://adamziegler.com/foundry/prop...5&coef=0.77&time=60&btu=2490&air=23.86&xair=5)
Using that the Reil style Burner I have been using should preform something like this:(Though the numbers don’t look right to me)
8 oz. = 11634 BTU's
2 lb = 23269 BTU's
6 lb = 40303 BTU's


I cleaned up the garage yesterday and can’t for the life of me remember where I put the flare for the burner scratch.gif so I just but an oversized union fitting over the end.
In the video I start the burner at 1/2lb about the same as a gas BBQ regulator and you can see the flame would be ok for roasting one marshmallow at a time but not much more.
I then turn the pressure up to 2psi and open the choke. This is the setting I start with to warm the furnace, crucible and all the tools I’ll be using.
Around the 35 second mark I turn the pressure up to 6psi. This is where I normally run the furnace. At this setting I can melt a full crucible of aluminum in less than 10 minutes and it will use around 1 pound of propane per hour. Hope that helps.

[ame]https://www.youtube.com/watch?v=tzBGJ8y1WO8[/ame]
 
In between the rainy patches it certainly is the time to be casting. At this point my furnace is ready to go, though I do need a proper crucible, my cobbled together tools and PPE is adequate and I have 1 smallish flask with enough greensand to fill it. I know enough to make a pattern and ram a mold but I don't yet know enough to cast one. My few test pours and ingot making have ended up with porous lumps and vary quite a bit from each other. I'm thinking I need some way to know the temperature of the melt so I can get some consistency, then I can work on improving the results.

It sure is a fun learning process though and I do have a couple of new ornaments for the shelf.

skull1_zpsotuaw2cm.jpg
 
Nice skull. See a lot of that around here stuffed into the hitch receiver of a pickup with red lights in the eye sockets and connected to the brake lights on the trailer plug. ;D
One thing I find with my green sand is the more I work it, pouring, mulling and just beating it up the better it gets. I’ve been using a big paint mixer in a ½ drill to work my sand but I’ve been giving this simple muller a lot of thought. It was originally posted on Alloy Avenue by jrandomuser back in 2013





http://www.alloyavenue.com/vb/showt...thought-I-would-share&highlight=Bucket+muller

Best of all, most of the parts can probably be scrounged for free. The one improvement I would do is to toss in a couple of rocks to help mull the sand. Purists might sneer at it but I can’t justify blowing the bank on a real muller.
 
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