Pouring Shanks: fitting smaller Crucibles?

I think Kelley (Al2O3) has permanent basins for aluminium casting and removes them before the aluminium has fully solidified so they can be reused.

 

You can use refractory to build one and coat it in black ice and sit it on top of the sprue for multiple use. I will be working on horizontal mold shape myself in the very near future. I will run some sims and see what I come up with for myself and I will share with you guys. I dont expect to reinvent the wheel but at least come up with something easy to mold and effective. These are some we use. B is one style we use for larger jobs and we often have them doubled. The small cup is for lighter jobs. We pour thin stuff so we have to hit it hard and fast and have to keep the metal from splashing out. B is roughly 3.5"x3.5"x3.5" and the small one is 3.5"x3.5" top...middle 3"x 1.75"....bottom 2.75"x2.75"...roughly.lol I am unable to pull those dimensions up to be sure at the moment...sad thing is I designed it and still have to look to see.LOL

 

IF (not likely) I were going to make a tumblehome pouring basin pattern, I might do it as I will try to illustrate. The pattern would consist of a main central piece, 4 loose pieces, and a couple brackets to hold it together while packing.

As I see it, the brackets (green) might be a piece of 1/4” plywood with 4 pins in each. It would be let into the base and top (though top bracket could actually just sit proud in most cases) and would have taper on the short pins so that the pins would keep the pieces together but the bracket would easily fall out of the loose pieces so that it would stay behind as the pattern was withdrawn. To withdraw the pattern, the center main piece would first be pulled out using a draw spike. Then the B and D parts would be pulled and finally A and C. In a production setting the work involved in making such a pattern might be worth it. But, for me, hand cutting is most practical at this time.

In the sketch below corners are shown as hard and sharp. In practice I would ease them considerably.

I hope the sketches are understandable.




The main central piece is outlined by dotted line.








There are probably easier ways to accomplish this.

Denjs

 

That's pretty close to what I had in mind, save with the side"away" from the sprue being a wide radius, and the one encompassing the sprue being a half-circle (for the radius).

 

Yes, I guess the loose pieces could have any outer shape desired. I usually just cut a squarish basin that sits over the sprue with the sprue being near one side of the basin. I personally like square corners as I think they arrest any swirling and promote iron just dropping down the sprue. But I know there are a number of differing viewpoints on that design variant.

Denis

 

I agree that the multi-piece pattern for a pouring basin is overly complicated for most purposes. My drawing and discussion was only intended to discuss the question raised as to how it could theoretically be done. I am not planning on executing any time soon. On the other hand, the principle might be used for a pattern for a part that had undercuts and then might be very practical.

Denis

 

I thought that this - a pattern - might help with consistency. (An area in which I need "all the help I can get.")

I've never used this style of spruing before, but I can tell it might well help more than I currently realize.

 

I was thinking the black ice would make them reusable hence making it worth the effort....if you need to help with the splash. If you do not have any splash I would not worry about it.
You could always mold them flat back like we do inside a square box to be used just like a core. Just have to make a box to mold in and either cut out or mold the core print for the core/cup.

 

Yes...rectangular is better. You can create a vortex on a long pour with round shaped basin and especially on a round sprue. Always best to make sprue shaped more rectangular...square will vortex too but not as bad as round. The vortex will suck air down the sprue and cause lots of porosity. I have some video of one of our jobs doing it ...somewhere... but on a square sprue. Since then we are making them tall and skinny...not square.

 

Until I talked to melt deck guy the other day that is all I knew about it as well.LOL Some type of graphite based paint they use on the ladles and furnace pouring lips to keep iron from sticking to them. Seems to work really well.

 

What is "black ice" in a foundry context? The previous use of that term usually means treacherous roads, if one speaks of Portland...

 

Graphite-based "paint?" Graphite, alcohol, bentonite, and a trace of shellac as a binder? Mix in a ball-mill, and then apply with one of those brass-n-copper "sprayers" sold by Freeman Supply?

 

For us home guys we might consider soot to be a substitute for black ice. Works nicely. Got a tiki torch? O/A torch overly rich works too. Furnace exhaust with air momentarily turned down is what I use.

On the other hand, Black Ice might be nice! Perhaps easier to apply the ice in certain circumstances.

Denis

 

No its a thick liquid....just slap it on with whatever is laying near by. I think that you should let it dry a little but I have seen our guys put it on and within minutes be using the ladle again. I tried to find a container of it while I was out there but I am not sure who had it last.LOL I would think it is cheap the way we go through it around here, but then again sometimes we are just wasteful.

 

I'm thinking there's 200+ mesh silica in that black ice stuff - that, or zircopax. The zircopax seems a bit more likely - more refractory. So, I'm guessing 30-50 % graphite, 10-20% bentonite, 3-5 percent flake shellac, and the rest the zircopax. Add alcohol, and rumble in a ball-mill for a while, then thin to a desired consistency before applying.

Should flame up good, too.

 

I’m hoping you can get some more info on Black Ice. Might be interesting to hear what the guys on the floor think of it. Also it’s composition would be good to know. Could it be applied to our crucibles to extend their life?

Denis

 

I was at the foundry today and did my solo best to make videos of a process that works for me:

The intro vid:

Part 2.

I wish I could have had someone tuning the camera as the quality would be better. I guess they convey the idea. Blowing the carved sand as I carve really helps me see what I am doing and what needs to be done. The carving tool is sharp on both the triangular and hoop ends.

Denis

 

That's some good green strength there. Sand I get to use is a lot more crumbly. Does a muller help that much?