Florida Man Metals

Yes, the bottom of the furnace/melter. I hope your shop doesn't get hot enought to burn bone to ash. You would definitely need some crazy PPE.

It is important to protect your foundry from metal spills and flux. Putting a 3/8 inch or so layer on the bottom makes for easier clean up of any spilt materials and prolongs the life of your foundry.

I used to use a layer of fine silica on top of my fire brick to protect them from spills. I recently switched to bone ash. It is much finer than silica and works better. More of a powder than a grain consistency.

Technically the books calls for calcined bone ash. I used bone meal from Lowe's garden department. Initially it turned black upon the first firing, then turned into the desired white ash.

     I read a while back that pyrite actually contains nanoparticles of gold in it. More recently I read about lithium being in pyrite. They are looking at it for industrial lithium extraction.

  I was confused as well and realized I might have committed this fauxpar. The only difference that I could come up with was that he was the one that originally started the initial thread. Correct me if I'm wrong.

   I appreciate the time you took to research the coal question George. I mainly came to the same conclusion but figured I would ask the right person their opinion. I know you're a recovering geologist so who better than you. Like you said it is murky water when it came to trying to research online. Not to mention throw in the confusion about true coal or charcoal aspect and all the warning to get rid of any bags that have gotten wet only muddied the waters more.

Goods you figured out my plan. Hey an asset is an asset.

This coal question might be another misnomer like the back flash suppressor that Frosty schooled me on so I thought I would ask.

George

Do you have to worry about spontaneous combustion due to oxygen absorption from the air? The oxidation causes a hot spot deep in the pile possibly causing it to ignite. I don't deal with coal I use propane in my foundry? Just curious thought this would be the best place to ask others opinion.

Fyi

    If you would have given us more information like your intended use we could of solved this for you day one. I would of told you to buy something like a lee lead hotpot. It has a heating element built into it. Add a rheostat or something to control the temp. 

  I would buy a quartz melt dish or something along those line if you're worried about carbon. I use a pretty large one for my silver pours. I'm not sure about a hot plate getting any crucible hot enough to be used in that manner (I maybe wrong). Why not a stainless steel bowl or something that transfer heat better and way cheaper?

Have you fired/used it yet. The only sure way to tell that i know of is to use it. It will form a hard outer layer that is grey in color. Nothing black should wipe off after it's first use. Graphite crucible are only good in electric furnaces. If you are using gas/propane the graphite crucible will erode away after just a few uses.

Novice here, but I would agree with Thomas. 

I pour my copper bars as soon as I can stir the pot with a graphite rod and not feel any solid pieces. The longer it is molten the more problems you will have.

He mentioned an iron mold. How is he keeping the the metal from sticking?

I coat my mold in soot from my furnace after I cut off the oxygen making it fuel rich. Similar to oxy/acetylene torches.

The soot allows a route for the gases to escape around your bar vs trying to rise up the center.

I also use an plate iron mold that isn't very tall to facilitate the escaping gases.

Appreciate it Frosty. I know I'm not exactly doing anything apples to apples with you folk, but my understanding is growing.

Frosty, you seem to be a wealth of knowledge with a knack for explaining idea to the uneducated (me).

You brought up a good point about refractory cement. I also use fire bricks (rated for 2700°F) for the base of my furnace. 

Why would someone want to cement fire bricks together vs just stacking them? Wouldn't all the expansion just crack the mortar anyways?

After all the repeated firings of my furnace the bricks have probably moved over an inch. I use a nice layer of super fine silica (aquarium sand) on the bottom of my furnace for that reason and to protect my fire brick from spills and whatnot.

Actually, the ones I use are called insulating fire brick rated for 2500°f.

Speaking of sound I've seen a jeweler use essential a tall, big box full of sand for his anvil stand. He said it helped with dampening reverberation. Not sure how big of an anvil you could go thou.

I used a one inch ceramic fiber insulation blanket (rated for 2700°f) doubled up and lined it with a ceramic coating (100HT). Mine is more of a furnace than a forge but it gets Hot...

All available from Amazon.

Thank you for the detailed explanation. Makes sense to me (the layman) in theory. However the sound the burner makes when I shut it off makes it seem possible.

I have no understanding of the physics necessary to build a proper burner. I felt it was a safer option to buy a pre-built burner with a proper regulator from a company than risk a homemade one. 

The manufacturer recommended a flash suppressor. So I followed their advice.

I guess better safe than sorry. Another case of the manufacturer trying to cover their *ss?

This might not be the right place for this but I was curious how many of you are actually using a back flow preventer?

I haven't seen anyone mention this vital safety device. I have always used one installed on my propane supply line.

It is designed to keep a flame from traveling down your gas line and reaching your tank. Boom....

And yes i have a real regulator attached to my propane tank.

I'm rather new to this forum and this might have been answered already. If so please excuse. I don't really run a forge. I run a propane burner in my furnace to refine precious metals and cast base alloys. I'm talking fairly high temperatures. Hot enough to refine paladium from catalytic converters.

Lead free pewter is like saying fat free butter. There is almost always some amount of lead in every pewter alloy. Whether it is cross contamination from machinery or handling and storage. For instance, if the source tin came from the Democratic Republic of the Congo where they still use leaded gas it becomes contaminated. Lead, tin, and antimony is very hard to separate due to their similar compositions. To truly separate it you have to heat them to their vaporization points and vacuum separate them one at a time. I'm talking super high temperatures 2260°C for tin. 

Lead/tin alloys are still very prevalent today. They are mainly used in items meant for decoration like picture frames and whatnot.

As for food safe. I honestly believe there is no such thing. Antimony is toxic. They say copper dishes leach toxins in your food. Same with cast aluminum.

Profitable? Like I've said it all depends on how you buy and sell. If you buy all your pewter from the thift store you wouldn't nake a dime. I can fit 500 pounds of pewter in a 5 gallon bucket if it is cast in large bars. The alloys need to be sorted with xrf gun to make sure they are alike alloys so you don't get hit with penalties on say a hundred pound bar because you added a pound of Antimony to your  99 pound Britannia bar.

My girl has family in Pennsylvania so I usually bring it up when we visit. The company keeps telling me I can send it up by freight but that's because they want to do more business with me more frequently. I only get paid for the tin content. They really want the free lead I give them. Lead is very useful for a multitude of scientific processes.

Word of advice. Fight the urge to pour large pewter bars. Melt and pour every item separate. Unless they are identical items from the same maker from the same time. Everyone keeps saying there isn't any tin smelters in the us. Technically smelters no, but there is a company called Tin Tech in Pennsylvania who refines tin from industrial producers who make items using tin. All different forms and compounds of tin. They use an xrf gun. It is a 500 pound minimum and took almost 2 months the last time I used them. Any pewter that contains antimony will be charged a penalty. I have personally shot (xrf) many pewter alloys over the years. I have seen so many other elements in them like arsenic and all kinds of other things I never would of thought would be in pewter.

Man I really need to reread and spell check before I upload. Forgive all the grammatical errors.

There really isn't any diffrence in buy from the thrift store vs the scrap yard besides the price. I use an old technique for sorting pewter alloys. If it does on the dinner table it is most likely not to contain lead. That being said lead free pewter can technically contains up to 1% lead of the total alloy. English pewter is easy to tell because it stays pretty white and Shiney even after a few years of oxidation because of the bismuth content. American pewters basic formula is 90% tin and 10% copper. It has a copper sheen appearance after oxidation. The only real diffrence is that the scrap yards melt pewter accent pieces of of silver plated brass. I get the same mugs, chargers, bowls and everything you buy from the thrift store buy at a better price. Every bin I pick up has some amout of sterling silver in it. Half the time the value of the silver pays for the bin.

I'm on the Treasure Coast. Yeah summer sucks here but the winter is like your summers in Wyoming. I don't know if I could do the Wyoming winters. It is 70°f right now.

I was stationed in El paso, Texas and when people asked me where I was located I told them North Mexico. I can easily see why some teachers taught that and wouldn't necessarily say they were wrong. No disrespect to your family but I don't think I ever had a class with them. Speaking in general.

*feasible

See I told you the school system in florida is atrocious. 

Thank you for the clarification. I had  seen a few conflicting things mentioning tin in the northern hemisphere. That doesn't change the fact it is an unviable option here. If there isn't high enough concentrations to mine for tin which makes it economically pheasabil. We would have to mine other metals to capture it as a byproduct and We can't process it here. Sounds like we will always be dependent on southeast asia.