Let's talk melting pots gentlemen...

[Springfield]

Magma's 90 lb pot is 3000 watts. I would hate for you to make a bunch of 90 lbers at 1200 watts only to find out it is way underpowered. It's not just a matter of increasing insulation, when you are in the middle of a large casting session, and I assume anyone who buys a 90 lb pot is going to do that, the last thing you need is to be dumping in ingots and have spout freeze up on you 'cause it can't melt the new lead fast enough. Personally I never saw a reason to get a pot larger than my Magma 40 lber, and I do this on a small commercial basis and cast 2-3000 bullets in a session. I'm also thinking that 1200 watts will take at least 45 minutes to melt 90 lbs, maybe longer. I'm sure you were going to already but do some testing on the first pot before you commit to the design. I hope this works out well, I would like to get another nice pot, then I can sell my RCBS 22 lber and have a Magma 40 and whatever yours turns out to be.

[cbrick]

Diddo Springfield,

My Magma 40 pound pot takes 35-40 minutes to get to casting temp (700 degrees) in the summer when it starts out at 90 degrees+, in the winter when it starts at about 35-40 degrees add 10-15 minutes to melt time.

Rick

[Cranium]

Magma's 90 lb pot is 3000 watts. I would hate for you to make a bunch of 90 lbers at 1200 watts only to find out it is way underpowered. It's not just a matter of increasing insulation, when you are in the middle of a large casting session, and I assume anyone who buys a 90 lb pot is going to do that, the last thing you need is to be dumping in ingots and have spout freeze up on you 'cause it can't melt the new lead fast enough. Personally I never saw a reason to get a pot larger than my Magma 40 lber, and I do this on a small commercial basis and cast 2-3000 bullets in a session. I'm also thinking that 1200 watts will take at least 45 minutes to melt 90 lbs, maybe longer. I'm sure you were going to already but do some testing on the first pot before you commit to the design. I hope this works out well, I would like to get another nice pot, then I can sell my RCBS 22 lber and have a Magma 40 and whatever yours turns out to be.

I understand where you are coming from with capacity. BUT....if you are able to purchase another pot that

• Has more capacity than the magma (if you ever need it)
• Has better temperature control than the base magma (PID)
• Is more efficient than the magma (better insulation = less power required)
• Costs less than the magma
  I'm sure you would be quite interested. I had been looking at a magma as well. Even the Master caster was an option for me. But I justify my purchases with how many bullets it takes to cast in order to pay itself off. I have to cast 8,000 to pay off what I've bought so far and I've done 1400 so far. <-- NOOB caster.
  
  Also, since he has his degree in engineering, I'm sure he knows all about prototyping and testing before declaring it 'all good'.
  
  
  

[Springfield]

Absolutely no offense to anyone but an engineering degree may need some input from some solid "experience" . I read quite a few books on casting and followed the sage advice here but actually casting bullets itself was the best teacher. Still not sure why the 90 lb capacity is so loved, seems like a bit of overkill. It will take twice as much electricity to get it melted in the first place, so unless you always cast at least 90 lbs worth of lead you will be wasting electricity and money. And if it takes 30 minutes to melt 40 lbs of lead at 1500 watts, it gotta be double that for 90 at 1200, unless you have managed to change the laws of physics. Or maybe you are just like that guy in the movie" My cousin Vinny", and just "cook faster" than most

[Idaho Sharpshooter]

Springfield,

1. when I start casting 960gr boolets for my 10 Bore Double Rifle or 900gr GC for my 600 OK it doesn't seem that big.
2. a 90 pounder is big enough to let you use it to alloy as well.
3. for the bottom pour contingent, you do not have to fill it.

I have two 4-cavity moulds for the 311247 buy ordered. Rotating them will drop the level quickly.

Rich

[Springfield]

I can do 2- 6 cavity 250 grain 45 moulds and put out 1300 bullets an hour and never strain my 40 lb Magma. That's 46 lbs an hour. I alloy lead with my turkey fryer and a 180 lb capacity stainless steel pot. I like to do at least 1000 lbs in a session. I would never alloy in my casting pot, like to keep it clean. Just a personal opinion but I don't think capacity trumps wattage. Bigger isn't always better. If you need to change alloy and do a small batch you will still have to heat up 90 lbs as it might burn out the element or at least damage/overheat the pot if you leave an area with no lead. Maybe I will just have to order a smaller version if he offers it.

[Idaho Sharpshooter]

Like my Grandfather told me; "vote with your wallet..."
I have the utmost confidence in Matt working this out.

Rich

[Cranium]

I can do 2- 6 cavity 250 grain 45 moulds and put out 1300 bullets an hour and never strain my 40 lb Magma. That's 46 lbs an hour. I alloy lead with my turkey fryer and a 180 lb capacity stainless steel pot. I like to do at least 1000 lbs in a session. I would never alloy in my casting pot, like to keep it clean. Just a personal opinion but I don't think capacity trumps wattage. Bigger isn't always better. If you need to change alloy and do a small batch you will still have to heat up 90 lbs as it might burn out the element or at least damage/overheat the pot if you leave an area with no lead. Maybe I will just have to order a smaller version if he offers it.

If it does not appeal to you that is fine. I don't think you should be dismissing it, as you are, without it being proven. Make suggestions, share your experiences, but don't judge a concept that has not even been created yet. Imagine if people did this when combustion engines were invented or electricity was harnessed as a tool. Encourage innovation rather than discourage it.

If the initial creation isn't up to par, it can be changed. If there are issues, they can be corrected. And even if the project is dropped, there is research and data that can be used by someone in the future.

Don't be a hater! Let's see where this goes.

[tonyjones]

This IS a discussion thread. Springfield and others have raised legitimate concerns. It harms no one to discuss these things among ourselves. In all likelihood this discussion will lead to a better product for those of us that end up purchasing and using them. I too respect Matt's talent and willingness to work on this project and I may well end up purchasing two pots. These discussions have, so far, been respectful, curteous and friendly. I hope that will continue.

Best regards,

Tony

[Idaho Sharpshooter]

Tell me again, how you get that 46lbs of alloy into a 40lb pot. Hee-hee!

When I sit down to cast, I do not want to have to do anything else until I decide to.
I came to the 90lb number based on being able to make a large enough alloy to cast a couple times if I opt to do so.

I also tend to an "Overkill" preference VS the notion of "just big enough". It's why I have a Dodge 3/4ton Diesel 4-door with an 8ft box, instead of a half ton short box 2-door with a gas engine. And a 10 Bore double rifle. With a 960gr mould, I will be casting a pound in less than two minutes.

The good news; Matt might offer a smaller capacity version down the road if there is sufficient demand.

There is also a difference between offering a suggestion and saying according to the laws of physics you can't do that.

I'd just go along with the notion that if you can't say something complimentary or helpful, then save it for a PM.


Rich

[Springfield]

I don't get 46 lbs into a 40 lbs pot, but I do cast for 2-3 hours at a time. I just keep feeding ingots in my pot for as long as I like without a hiccup. I know 1500 watts in a 40 lb pot can do this. I have no idea whether a 90 lb pot with 1200 watts can do this, and I suspect neither do you. I am interested in getting one of these new pots if they work. I am just trying to give the maker the benefit of my experience. He can use it or not, simple as that. I'm through playing the Devil's Advocate, and will just wait and see how this all pans out. I hope it does, it sounds like it would be a good quality pot.

[Cranium]

i don't get 46 lbs into a 40 lbs pot, but i do cast for 2-3 hours at a time. I just keep feeding ingots in my pot for as long as i like without a hiccup. I know 1500 watts in a 40 lb pot can do this. I have no idea whether a 90 lb pot with 1200 watts can do this, and i suspect neither do you. I am interested in getting one of these new pots if they work. I am just trying to give the maker the benefit of my experience. He can use it or not, simple as that. I'm through playing the devil's advocate, and will just wait and see how this all pans out. I hope it does, it sounds like it would be a good quality pot.

+1

[happy7]

Well, it sounds like there are going to be option in terms of pot size. Personally, after having used a 40 pound pot, that is big enough for almost every application, and I cast some large bullets. The problem for me with going bigger than that is that even when you have a small casting job to do, you will have to heat the whole pot (if you left if full of alloy), you are going to 90 pounds of alloy in front of you to make you sweat (which in arkansas in the summer is a consideration), and if the pot is deaper, it is going to be harder to ladel cast from.

The great thing about Matt is that it sounds like he is going to be flexible in his design, and those who want/need the bigger pot can have it, and those who prefer the smaller pot can also have it.

Springfield. Please stay involved in this topic. I certainly value the input you have had so far. You have a lot of experience we can all benefit from with the design of this thing.

[midnight]

I'll keep lurking here. This pot sounds like what I have been looking for. A 40 lb pot is plenty for me but we will see what the consensus is. I am especially interested in the design of the mold guide. I need it adjustable front to back, vertically, and horizontally. I was thinking of doing a PID controller myself but having someone else who knows what he is doing design it appeals to me more and more. I might need two of them. I wish I had some technical expertise to contribute but I do not. I can just indicate what I would like and hope it parallels the rest of the members.

Bob

[Matt3357]

Hello everyone,

It seems that I have missed a few postings to this thread and need to mitigate a few things. First and foremost, a 90 lb pot is huge and 1200watts is not much heat on it. The more I think about it, the more I think that a pot that size really needs to be on a 240v circuit only with about 3000watts. That puts it around 12.5 amps. I came up with the 1200watts because that is the size I can find a good source of without having to go through a company like Watlow or Hotwatt or Chromalox etc. I can source the 1200watt at an affordable price and don't want to get involved with a company until after I make the first couple pots and then am able to make a large enough order from them. I will see what I can find and get back to you. But I do agree that 1200watts just would not cut it.

As far as pot capacity goes, whatever flips your switch. I can adjust the depth of the pot very easily thereby adjusting the capacity. The one I make for myself will only be 50-60lbs as that I what I want/need.

Also, if you remember back a couple pages, I outlined what kind of product offering I was planning on having once things got rolling and that included smaller pots for ladle casting and a much larger pot for smelting. If you know what you want, I am sure we can do it within reason. I can do this because I will fabricate each one, not mass produce. Be thinking about what you want and please don't criticize other peoples decisions. I started with a 90lb design, because that is what Idaho wanted, no big deal to modify, it just gave me a place to start.

I appreciate everyone's input and while I have just completed my degree, this is not my first rodeo. Experience is the best teacher by far, and after building my own first pot and designing and building my shot making system, I have learned a lot. I am here to answer any questions or concerns anyone has, but lets keep them civilized.

BTW, if anyone knows where I can source band heaters for an inexpensive price, please let me know.

Thanks,
Matt

[cbrick]

Like many posting on this thread I am very interested in these pots. My Magma 40# pot serves my casting needs very well, my interest lies in a bottom pour smelting pot of about 100# but not with a 1200W element and not with 240 volt. Given the time it takes the Magma 1500W to heat up 40 pounds 1200W and 100 pounds I don't think would work plus, I rent and dont have 240 available. No idea what it might cost to have 240 installed or even if the property owner would allow it.

I don't know what the max wattage on a 120v line would be, I think about 1500-1800W but not sure. I would expect a longer heat up time with 100 pounds of alloy but 1200W I think would be way to long, possibly what I would like isn't feasible. Don't know.

Rick

[Matt3357]

Rick,

I don't see that happening unfortunately. For a standard 120v outlet, you are limited to 15 amps that would put you at a max of 1800W. Even 1800W would be too weak to be useful. You would need a much greater heat source. Do you have an electric dryer? If so, you could make an extension cord to run it outside to get 240. I know my dryer is hooked to a 30 amp breaker. Maxed out you could run 7200 watts. I would probably put 5K watts on the pot. Should be plenty of heat to melt 100lbs of alloy in about a half hour. You could also go the turkey fryer route, which is what I would do in your position. It would be much cheaper and more convenient for you in your current residence. I hope I helped.

Thanks,
Matt

[bwgdog]

Former electic lineman here. Been to many homes while working. New homes are wired with a 15amp GFI on the garage and outside outlets. Most casters will not have one pot going in the garage. Normal is- tv-radio-fans-refrigerator-coffee pot-hot plate-did I miss anything? We all need to be aware of the safety limits of our wiring systems and if in doubt-check it out. bwgdog

[Matt3357]

Good advice bwgdog. I guess I used to wiring up my own circuits so I know what is loading on what line. I don't want to give advice that could be used against me, so I would definitely recommend anyone that buys one of my pots to be sure to have their circuits checked out to make sure they are not being overloaded and can handle whatever the load may end up being on my pots.

Thanks,
Matt

[Cranium]

I did a calculation with the assumptions of:

• Pot Width 6"
• Pot Depth 8"
• Pot insulation 2" rock wool
• Pot Weight 10 Lbs
• Pot Lead Capacity 92.7 Lbs
• Top Surface Area (ft2) 0.2
• Pot shell surface Area (ft2) 3.14159 <--- Pi by coincidence
• Starting Temp 80°F
• End Temp 700°F
• Heat up time 30 min

A 90 lb lead capacity pot would require 2750W to achieve a 30 minute heat up time. This is well beyond the capabilities of a 15A 120V circuit [total] limit of 1800W.

To check my calculations, I sized down the pot to 5" W x 5" D (40 lbs) and this resulted in 1500 W required to heat the lead in 30 min. This seems to be on par with what others have reported and what other pots have for their heater size.

With this in mind, the max amount of lead that a 15A 120V circuit could heat to temp in 1/2 hour is 50 lbs. This assumes a dedicated circuit so in reality, maybe 45 lbs max.

I based my calculations on formulas found here: http://www.chromalox.com/catalog/res...ng-Liquids.pdf
The formula used has these assumptions:

• Melting point of lead = 621°F
• Specific heat of solid lead = 0.0306 Btu/lb/°F
• Specific heat of molten lead = 0.038 Btu/lb/°F
• Heat of fusion/lead = 10.8 Btu/lb
• Specific heat of steel crucible = 0.12 Btu/lb/°F
• Radiation loss from molten lead surface = 1000
• Surface loss from outside shell of pot 62 W/ft2
• SF = Safety Factor 20%