So let's start pouring our own ShinyBars branded silver bars! It can't be that hard right? Well, the journey begins....
Over in the ShinyBars Hand Poured Silver category you will find all of the beautiful hand poured products we come up with! In addition to the "beautiful" products, you will find the monstrosities in the Reject Bin. I will try to address both the beauty and the beast in this blog post!
Let's start with a beauty!
To the left is our 10oz hand poured loaf silver bar. It is a product born out of consistent flow of molten .999+ fine silver. Consistent flow you say? Well, we have found that finding an optimal speed of pouring silver has been extremely difficult! If you pour too slowly the silver hardens before it settles into the beauty shown to the left. If you pour too fast you end up with sharp edges and a deep dimple in the middle. Finding the balance is the key and this balance changes depending on what size bar is being poured! As of this time our pouring is so inefficient that it takes about 3 attempts to arrive at 1 "pretty" bar. As we practice and learn more the process is getting much more efficient!
Now let's take a look at a beast!
The bar to the left was a complete failure! Well, not a "complete" failure as it fell within our weight threshold for a "10 troy ounce" hand poured silver bar. It is UGLY! What caused this? One of two things happened (or a combination of both).
1.) The mold was not pre-heated enough
2.) The pour was entirely too slow
My guess is number 2 since we heat the molds pretty thoroughly. When pouring too slow the silver starts to harden. If it starts hardening it creates a bowl of silver so when you continue pouring it just fills the silver "bowl" instead of the mold. And in turn you end up with the blob of fine silver to the left.
Common Problems and Solutions
1.) Graphite blob
Our nemesis has been the graphite blob that plops out at the end of a pour! What is it? Well, graphite crucibles break down slowly under such high heat. When it breaks down the material floats on top of the melt. When pouring it ends up being the last thing to come out of the crucible. What does it do? It plops out on the "pretty" pour and has just enough force to push the edges of the pour out and create sharp edges. Also, it leaves a crust/messed up spot on the bar that has to be sanded off. I, being a cost cutting freak, hate sanding on a silver bar! First, it wastes material and secondly it wastes time. The solution? We haven't really found one! We have tried borax, stirring rods, mix of borax and stirring rod, etc. and still end up with the "fire scale" as it was described to me by an individual who has a lot of experience in pouring. What is our workaround? Simple....no! Melt more silver than is needed to pour the bar and "learn" to hit our target weight! This results in awesome looking bars but the downside is that we are still learning to pour consistent weights.
2.) Pour too fast
Pouring molten fine silver too fast causes a couple of issues. First, you risk splattering blazing hot silver out of the mold and potentially on yourself (please wear proper safety gear and ensure your work area is non-flammable!***). The second issue is that it will push the edges out similar to the graphite blob problem above and you will end up with sharp edges instead of the desirable smooth/rounded edges. The final issue is that when using the above mentioned method of melting more silver than is needed for the pour, pouring too fast tends to result in an overpour.
3.) Pour too slow
This was pretty much covered in the above about the "beast" of a bar! Pouring too slow results in silver hardening before it should. It will harden in the mold and create a blob of silver instead of a bar. Go even slower and your silver will start hardening to the inside of the crucible and sticking to the sides.
4.) Under pour
Pour too slow and you usually end up with premature hardening and an ugly underpour. Gotta hit the weight!
5.) Over pour
Enough said, too much silver is poured. This problem persists but is certainly better than an underpour!
That's it for now! Future episodes will cover more aspects of our hand poured silver endeavor so keep checking back.
***Proper safety gear includes a face shield, leather apron, leather gloves (we use welding gloves), etc.