Pouring Shanks: fitting smaller Crucibles?

I'm have an A4/#4 and an A6/#6, both Salamanders. Bought a few months ago at Legend. As I have yet to build my own furnace - hopefully, a Gingery-style lifting-body version, using Insulating Refractory Bricks - I will need to do foundry elsewhere.

Thought is to "roughly" duplicate the Mifco pouring shank that I've downloaded pictures of. Theirs was stated as being for A10 and larger, if my memory serves. Dimensions will need changing to fit smaller pots. (?)

Comments appreciated and welcomed.

 

Salamanders taper out all the way to the top. All you need is a simple ring, the hold down is unnecessary.

If you do make a lift off furnace you can avoid lifting tongs and make an open ring "C" shape to slide around the crucible low then capture it when you lift. I would make a separate shank for each crucible size rather than spending a lot of time trying to make a universal shank which does not fit any crucible well.

I can't criticize MIFCO however I don't know how I would use lifting tongs to safely set the crucible in the picture into the shank in the picture. The crucible is tapering inward where you would have to grab it.

Maybe an expert will happen along and explain it.

Design in the picture would not work in my foundry since I work along and the shank looks like it would not stand on it's own so I would have to build some sort of support to hold it safely upright while I was loading it. And all the braces and mechanism add extra weight. A pot full of liquid metal is heavy enough without adding unnecessary weight.

I did add sheet metal to mine to keep my hand cool and make a stand. I don't regret it.

Here was my first iteration:



That was an attempt to have one shank work for two sizes of crucible. It also had a hold down incorporated in the shield. It worked OK but the extra hardware was in the way.

This is not a very good pour but you can see the simple shank I use now. It works well for me.

 

Old Iron Farmer's simple ring pouring shank is what I use for a A25 and AT30 size crucibles, it grips on the lower half of the crucible and uses the weight of the crucible to "cock" over and jam in the ring when pouring. Also by having the ring below halfway it balances better as the molten metal depletes in the crucible so you don't rely on wrist strength to pour the metal. I added a couple of small tabs/ears of steel on the ring to help stabilize the crucible and am very happy with performance. In the second photo you can see the crucible ready to lift, at the time I forgot a small brick or puck of refractory to rest the crucible on to raise it enough to prevent the shank from getting in the way of the crucible lifter when I lowered the crucible onto the pouring shank. Also you can see the stainless steel radiant heat shield that lets you hold the shank close to the crucible without overheating your gloves from the radiant infra red heat.

Edit: There is a 'T' handle not visible on the end of the shank to allow one hand to rotate the shank when pouring.

 

Yes, big pots. Thus far: 1) watch the weight, and 2) simpler is usually better.

Then why does Mifco make such a Beastly Brutal Clanger, then?

 

I don't know... the angle of the handle shaft means you'll be fighting the weight of the crucible the entire time you're pouring with it and the end of the shank handle now has to move in a circular arc instead of being rotated by wrist action. It looks like it was designed by a safety committee after the ergonomics team member quit in disgust . I can see it working for aluminium but not for anything denser, bronze or iron would typically be a two handled affair with 20 or larger crucibles if you have a second person to help.

A straight shank is helped by having the moulds off the ground so you don't bend over to pour, that shank you show may work for lighter aluminium poured into moulds sitting low on the ground.

 

if you have watched my videos, you have seen my shank cant get any simpler, there are three concerns when designing "your" shank ,
1) the average height of your molds,
2) how tall are you
3) where are your hands comfortable

in reverse, I like my lead hand(closest to Crucible) in my case left hand, almost fully extended downward,
the shank should ballance or be crucible light in this hand
my control hand right should be about middle of up and down, probably a hair above your belt

1 & 2work together my molds are short, 7 inches , im tall 74 inches , i need the crucible paralel to the deck , with the lip of the crucible about 9 inches off the deck , while im in a steady stance, leggs apart and bent

to make all this happen, my shank is about 5ft 6 inches , and there is a 15degree from the shank handle to the ring holding the crucible



V/r HT1

P.S. I'm adding adding the tabs pictured in Marks post above to my shank great idea

 

I figured I would need to make most parts adjustable, i.e. the main angle.where the "pole" touches the ring. Also, I had thought to use a "fabricated and welded" hexagon of 1/8 inch hot-rolled steel. (Small, light(er) pots here). Length of Mifco's Spendy (~ 340$) shank is 41 inches. I thought to order a 4 ft. Tube.

 

4 foot seems short, remember you have to have a couple of foot between you and the molten metal

I used 1Inch pipe from the hardware store

V/r HT1

 

It also helps to have a larger target. Not for everyone I suppose, but I cut a pouring basin about 4” square and 2” or more deep with tumblehome sides. Of course, I am using a trolly not a hand shank. But, with the large target, tumblehome sides and good depth it is a whole lot easier to get the metal into the basin and the tumblehome and square shape lmakes slopping backup and out of the basin unlikely. And the big target encourages rapid dumping of metal at the start of the pour which makes for rapid filling of the basin and tends to keep the sprue choked. It Works better for me than small round basins anyway.

Denis

 

Will keep that larger "target" in mind.

 

They say a good rule of thumb for pouring basins is one and a half seconds of your pour rate to fill. So if you are pouring at 3 pounds per second than you need a 4.5 pound pouring basin... this rule of thumb is for suggested smaller pour weights. I suggest using the average of the beginning of the pour and the end of the pour for better yield but suggest using the initial rate for quality.

 

Not sure what tumbehome means in this context. Have seen that term used in regard to boat construction, where it refers to the shape of the hull - really fuzzy to me.

 

Interesting. I did not know this rule of thumb. But it is interesting and surprising that it pretty much matches what by trial and plenty of error I have come up with using. Here’s a pic of one of my recent pouring basins which is 4 x 4 by about 1 1/2 and weighs 4 1/2 pounds.

I would add that a large non-spilling basin encourages me to more rapid pouring as a side benefit.

I am using the term "Tumblehome" here just exactly like it’s used in a boat hull. I am not sure everyone would agree with my idea but it sure seems to make sense and work well for me. And the recurve of the side of the pouring basin tends to redirect any metal back into the pouring basin as opposed to straight or even worse curving sides that tend to slop metal out of the pouring basin. Here’s a picture showing the tumble home on my base and from a couple of days ago. The top is up in the photo.



In early days I used funnel-shaped basins. They tended to really result in metal falling down one side and climbing right back up the other—- lots of spills. Also they tended to empty slowly due to swirling.

Denis

 

These are for my A6 and A10 crucibles.
Just 1/4" rod bent into shape.
Hand pressure closes the tongs for lift out.
I squeeze the pouring shank to open it up to slide up the crucible, then let go for it to grip the pot.

 

Is this shape of pouring basin hand-cut? I could picture a complex jigsaw-puzzle way of doing otherwise (as in a pattern) but then ramming it up...???

 

Dennis, if you haven't watched Martins video's I highly recommend doing so. He is a wealth of knowledge and has been passing it on.

 

Hand cut? Yes, I us a clay modeling tool like this


and a compressed air blower and carve away sand and simultaneously blown out with air. Works welll and is pretty fast. I lerave the sprue pattern in place while carving. I used to use a spoon to carve but the clay tool plus air is a lot more efficient. I'll make a video soon.

I used to use patterns to make the pouring basin and still do in one pattern. In that case I use the basin pattern inverted (narrow end UP) as it passes all the way through the cope. I draw it on the drag surface of the cope. I do hope that makes sense. But in most cases I just carve the basin.

As you suggest you could use a main basin pattern piece with 4 loose pieces to make a basin with tumblehome. But that has, so far, been too much trouble. Another option would be to make the main cavity for the basin with a pattern and then just carve the tumblehome into it.

Maybe I have tumblehome "on the brain" , but, since using it, I rarely have metal outside the basin when I finish pouring with my trolly.

Denis

 

I have pieces - patterns - that could work well, but again, ramming around them...