Bulk Scrapping Furnace

My pile of rims is getting quite large and I would rather melt them in a controllable, less messy fashion.
I have a burner from a commercial oven and have done a mock up of what I'm thinking.


I did a test firing with a weed burner wand and the large flame came when I pushed the turbo handle on the wand. I have a 30 psi propane regulator on order for more control.



Before I go any further with this build, I need some guidance from you experienced gurus.
Since the burner is inside the burn chamber and will be only an inch or so away from the rims, is this thing going to blow up on me if the burner gets red hot????

 

I want the drip, drip, drip into ingot trays.

 

I've got 9 rims to do.
If the drips are fairly fast they make a nice ingot, if they slow down you get a layered ingot.
I have a 4" x 4" x 1/2" chunk of steel on legs that goes over the drip hole to keep it open, works like a charm.

Got the regulator today and did another test.The regulator must have an excess flow valve in it. I could get about 3 inches of blue flame and then it would snap and shut down if increased further.
It looks like option 2 will go into effect too.
A Rocket stove on the back with the flame entering under and past the burner. That is the red box I drew in picture #1.

One word of caution: if you want to keep your eyebrows and eyelashes, don't wear a hat when sticking your head over the front of the drum.

 

If you are running it off of a 20lb tank you probably tripped the internal safety valve. I've had a similar issue before when using modern 20lb tanks to test run antique tractors - if the demand gets high enough, the flow speeds up and it snaps shut on you to keep you "safe".

 

I have a ton of aluminum cans I want rid of and think I may need to build one of these. Something about shoving dirty old cans into my crucible just make me cringe. LOL

 

Aw dude. Shove those dirty old cans into a plastic bag instead of your crucible. Trade them to your scrapper for a single bell housing and you'll be way ahead! Lol.

Pete

 

Just say no to cans! You might as well melt an old ladder or junk window frames. Cast to Cast is the rule.

 

Can-demonium works well as an addition to zinc, so as to make Za-12/27...

 

Is that the consensus on aluminium cans? I've got a ton of them as well, but I swear I probably lose 50% to slag. I thought it was just because they were heavily painted, but I read elsewhere that you have to melt them really quickly, or they just oxidise. (Sorry, this is almost a repost of something I posted elsewhere here, but it looks like a different set of opinions!)

 

Guys use them but they're alot of extra work, crud, and entrapped moisture. Other more favorable material is just as easy to find once you start looking, and once you really start using other material chances are you wont look back.

Pete

 

In the distant pat of my youth I melted cans from time to time, mostly for amusement. They'll work when you're just figuring things out, but I think you'll get better results if you use a more appropriate alloy for casting. If you cast your eye about you should be able to find a bit of discarded auto parts or the like just laying around. I recommend weighing and measuring volume of unknown metals though, it can be hard to tell aluminum from zamak from magnesium sometimes. With a weight and a volume, you can do a little math and be pretty certain what you've got....and get better results as you'll know what to expect. Also important is you likely don't want to melt magnesium and you want to keep the zamak from getting too hot.

 

It is true, I did a couple of hard drive cases, a few frying pans and I couldn't BELIEVE the lack of crud which came out. I just wondered if there was a technique or something! I heard folk going "you need more table salt", etc. but I thought that was for degassing.

 

Hey Jeff: You should put an extruded muffin in each melt of cast. You won't notice the addition and the muffins will soon be gone.

I've got tw dozen rims to melt and am trying to figure out the easiest way. I'm thinking a lined drum has to be it.

 

Very true, make friends with a mechanic or body man and you'll have access to all of the high quality scrap you're likely to need. For example, several years ago, I was casting a part for a friend of mine and a friend of his owned a few body shops, he was very intrigued with my casting process and he said they very frequently have cars come in with alloy rims damaged beyond repair and offered to let me take as many as I needed. There are several ways to cut rims into manageable size pieces, I use a table saw with a carbide tipped blade (full PPE mandatory).

 

Round two
That burner is a propane hog so it's out.
Next is to try a wood fired version.
Started on it before winter set in.

 

Jeff covers it all there. The minute I switched from recycled anything Al to known LM25 (A356) the results were a mile forward.

I had a pallet of fittings I had cast by a local foundry (project went sour leaving me with a heap of lm25 scrap) a good alloy behaves so much differently.

There are enough headaches.