Well guys, for some extra cash on the side, to outfit the volvos with some more goodies, i need to build a foundry.

One of my profs is doing some research and currently is paying through the nose for casting new prototypes in aluminum.

Soooo, i mentioned people are doing some backyard foundry work.....

and he wants me to build a foundry. I made a little one out of type 3 portland and zonolite, and it worked quite well! did some lost-foam casting of the small design he had that came out flawlessly... and all the concrete slumped off the walls and melted. so it went to the jobsite trashbin.

so now comes time to build the big one!

here's the conceptual drawing...



The lid isn't shown.

what it is is 2" of cerawool ceramic insulation at 6lb/ft^3
1" of dukast 2800 refractory castable (good to 2800f working temp, it's an aluminum silicate cement, gotta wear a respirator handling it, free silica is nasty stuff!)
all inside a garbage can.



there's the garbage can and beginnings of a base.

This will be able to hold a 6-7" diameter crucible, at full length, i could probably melt up to 40lbs of aluminum.

Most of these castings will be in the 15-18lb range (model Shovel buckets, dozer blades, teeth, etc...)

The furnace will use the old burner head from my grandparents oil heating furnace that's been sitting around since they converted to natural gas.

The pipe shown in the picture was for a different design, this one will be 4" in diameter of opening and basically be a self contained unit.

I intend to run this on filtered waste oil thinned out with a bit of diesel (virtually free).

I'm hoping to get the refractory cast this weekend, and hopefully have the thing fired up sometime during the week next week to melt some ingots and reduce my aluminum scrap pile (I've got a b5252s block to melt down for some nice high silica stuff that runs real good

The dream for this project: 8v and 16v manifolds, no clue if it's doable yet, but i'm making enough cash casting a few simple parts CNC'd out of foam for the prof that it'll be worth it

Total cost for the furnace and materials so far is $334 for the refractory, ceramic wool, trashcan and scrap steel. i anticipate ~$450 after my special tools are built and i've got some casting sand, not counting new safety gear which is DEFINITELY needed for this.

used up some of the scraps and got some iron casters.

decided to use #9 wire through the garbage can and wool to reinforce the refractory, along with some stucco mesh. The plan has changed to just using one 10" sonotube in the middle, and then from the garbage can, the ceramic wool, a layer of wax paper, stucco mesh held by the #9 wire, then the refractory in/around that, and lastly the sonotube in the middle.

fitted the ceramic wool liner!

still need to cut the burner holes/such. and get the bottom ready for casting.

I think you might have the ADD, but it's alright 'cause you seem to be good with that.

I've wanted to build a refractory for a while, since I read this cool old book on the subject. I'll be watching.

I think I AM ADD




got a burner!

Hot stuff

took two bags of dukast 2800f castable refractory to fill it to the brim of the can around the insulation. Used a square patching trowel to the the material in, burnt a 5A drill out with the paddles on it, and used a concrete vibrator and a 1x1 to tamp it down around the form, amazing how much air came out!

still figuring out my cerawool gasket for the lid and the lifting mechanism, but i got my mill tooling today!

however, i was playing with the burner, and definitely need to preheat the used oil and cut it at least 50/50 with diesel...

to do this, i've got a black steel tee, i'm going to put a spare volvo blockheater in the middle of it, and put plugs in each end with a fitting in them.

i figure 400watts should be be enough to raise it about 25 degrees, but we'll have to see. I may need to try having two heaters, one before the filter and one after.

time to do some jiggering to finish welding up the milling machine table, and it'll be in use for a variety of things -- including buttoning up the 8.8" for the 220.