dimensional analysis from back in physics 101 was the most useful thing I've ever learned and I have an engineering degree. i find it's easiest to write it out explicitly so you don't have to remember anything or do anything in your head
1. Place crucible on kitchen scale set to metric (grams). 2. Zero the scale. 3. Fill with water to a level you're comfortable with if it was holding molten metal. 4. Read kitchen scale. That's the (hopefully safe) usable volume of your crucible, in cubic centimeters. 1 gram of water = 1 c.c. = 1 mililiter 5. Be sure the crucible is dry before use.
I'm always amazed with the number of people that suggest filling my crucible, that is going in a 2000F furnace, with water and never mention the idea of thoroughly drying the crucible out before using it.
Complex shaped chambers are hard to calculate so physical measurement is fast and fairly accurate. Using bean bag beads, fill the chamber then pour them into a measuring jug. Measured a pool filter leaf basket, engine inlet manifold, hollow door and many others this way.
Trivia: A cube of water with the sides of 10cm, it's 1 liter of volume and it weights 1kg. So in the metric system we have distance, volume and weight all connected to each others 😃 Adding on, 0° Celsius is water freezing point and 100° C is water boiling point, all is linked to water 💧 I don't know how someone would prefer the imperial system over the simplicity and logic of the metric 😊
Well if we're going trivia wasn't a meter based on a fraction of the the distance between the north pole and the equator as it ran through Paris or something? Then they found out the number changed and the changed the length again and now its based on the distance light travels in some whacko number of time increments? I do agree that having things tied together and based on 10 is a far simpler way to do things. I don't know that anyone will argue that calculating fractions of an inch is better or easier than counting
@@markfryer9880 Mark I love you, but I am amazed how proving the volume the volume of 6KG of brass is equivalent to 4 pounds of aluminum turned into the "volume of my crucible" as the main subject. Nearly 80% of the content of the video was based on defining the numbers on the product and proving them out, yet the sidetrack that I took at the end has turned into the main point that people have landed on. I am really amazed that people took such great offense (not you) at me multiplying three numbers to calculate the volume. It was almost as if I uttered the great blasphemy "how dare you ask us to do arithmetic!". I realize that things change at different altitudes. That wasn't the point of the video, The point was are 6kg of brass equivalent to 4 pounds in aluminum? Yes they are.
Great video. Even though I had to find this out on my own a long time ago. This should help anyone out that isn't afraid of numbers. To add to the thoughtful advice in the video. It's ok for customers to get product info from suppliers, and to check out details when they feel confused. Thanks 🙏 blessings to you.
Thank you Arik. I'm always a little surprised when someone tells me they stopped watching when I mentioned a number. It's crazy. It is alright to contact the manufacturer/supplier. Often times, not always, they readily provide the information.
@@swdweeb Of course the manufacturer as well. Right shockingly disconcerting to get backlash for trying to help others. Generally it's because the individual is afraid of how little they know to learn anything new. It can have nothing to do with their intelligence but that they see themselves as not capable. A negative feedback loop brought on by anxiety, exacerbated from lack of actual social interaction. It's becoming more and more common as people lose themselves into social media platforms.
Great video, thanks for making it. Went to the PCM website and it states the #6 is the weight in lbs of aluminum that the crucible holds, and the kg number is the kg of copper or brass it can hold. So a #8 - 10 kg will hold 8 lbs of aluminum, OR 10 kg of brass or copper.
Its funny, I got a comment on this video just a day or two ago where the guy started ranting about the stupid American measurement (his words not mine) . He even went so far as to say if computers were base 10 they would run faster. Guess he didn't understand the beauty and speed of arithmetic shifting. Sorry, I digress. It's amazing the comments this has generated. Everything from "when you divided two numbers my head exploded" to "just fill your crucible full of water"
I've just started getting into it, so far I've bought 3 crucibles, and I have been wondering myself, when you said I also was like, duh, how did I not see that
I actually really like your casual yet straight forward approach to your videos , I have actually learnt a lot here. Also as one that was looking at Petrabond thinking this is going to get expensive, you have made my day with your in depth discussion on the green sand. I'm going to definitely give this a go, Would of been interesting to see how a petrabond mould holds up to your latest batch of sand? Understandably the cost far out-ways the minimal benefit or loss to detail, but would have been a great comparison of detail using the same mould.
Thanks Jim. I actually thought about doing a comparison...briefly... but didn't have any new petrobond and didn't want to buy a batch just for one test. I'm hoping to get out and cast a few things today, maybe I can show some of the detail the new green sand picks up. Be a good way for me to advertise my sand again 😄 www.plmfoundries.com/product-page/green-sand
The good old days. Does anyone remember sitting in school saying " when will I ever need to know this"? Good stuff. I forget all the formulas I need sometimes and have to look them up but its satisfactory knowing how to read and calculate them
Excellent video so informative! First crucible arrives today from Amazon. Went to the same crucible dealer website you mentioned and got to confused with there blerb..changed website and payed to much..Doh!!!!thanks for the heads up video
Maybe I missed your reasoning for doing it the way you did but I would just fill it with Sand or BB's then pour that into a measuring cup to get the volume of the crucible?
Based on the number of similar comments I've received, I realize now that multiplying three numbers together to get the volume was an issue for a lot of people. My intent was to simply prove that the volumes calculated based on the weight of brass and aluminum were reasonable for the volume of the crucible. My sincerest apologies to all that were offended by the use of arithmetic during this video.
Another great video Sir..A lot of info in there! Wished I had it a week or so ago when I was casting that bronze slider and didn’t have enough bronze in my crucible!
Great info Perry. I have baught a few from PMC too. A lot of the crucibles actually explain that in the description, thats how I first figured it out. Thanks for the info on how to figure out the volume.
A much simpler way is to multiply the # of the crucible by 10 to get the volume in cubic inches. A #12 crucible is 120 cubic inches, aluminum weighs .1 lbs per cubic inch.
I have a simpler method. Measure the weight of the crucible, fill the crucible to the top with water, measure the weight of the crucible and water, then subtract the crucible's weight from the combined weight to get the weight of the water. If your measurements are in grams, then the weight of the water is the volume of the crucible in cc's. It eliminates the protracted calculations, and is more accurate than estimating the diameters, depths, etc which introduce errors. Now if you want to know the volume you can pour, then fill the crucible about 80%, or whatever volume of molten metal you feel comfortable having in the crucible and do the same procedure with the crucible partially full. Just remember to dry your crucible in an oven to eliminate all the moisture before using it for a melt. FYI: I have purchased crucibles online and the physical size of the crucible can vary from one manufacturer to another. One manufacturer's 8 kg crucible is another's 10 kg. Stick with the Morgan crucibles to determine the size. Take the Morgan crucible dimensions and compare the dimensions of the crucible you are purchasing to determine a reliable kg weight for the crucible. I have seen crucibles of the same dimensions listed as 8 kg, 9 kg, & 10 kg. It is for selling purposes. I am guessing that the 8 kg actually represents the weight a 80% full, 9 kg - 90%, and 10 kg - 100%. I don't know anyone who would do a melt to fill 100% of the crucible, 90% is a push. Personally I am comfortable with 80%. Bottom line, I don't generally work with the weight of metal when casting an item, I am concerned with the volume because the same part is going to require the same volume regardless of the metal being used.
You forgot the step of drying your crucible thoroughly so it doesn’t break or explode when you heat it. I’d never fill my crucibles with water but I’m just weird. I’ve never been concerned with the weight either but three or four years ago when I made that video a few people had asked what the numbers meant.
Another great video! Conversion can sure mess with your head for sure! I have had some odd shaped containers to use for melting and being that calculation would be too complex, I filled with water and poured into a measuring container. Your method is far better for sure and with a bit more volume than you need for a piece, you can cover the extra material needed for the in and out holes :) Thanks for this, I found it enriching!
AH yes # Pound gives a new dimension to the whole #me2 thing 😂 Weird they use an alloy for a measurement, it can vary depending on the ratio Thanks for this science lesson, I learned something today 😋👊👍
Yeah, there are all sorts of things in this world that are the way they are because that's how we've always done it 😄 Glad you got something out of it.
Awesome video and great explanation. I got what I needed when you said pounds and kilograms but you were having way too much fun with the density calculations so I kept watching. Lol. I am an aerospace engineering major that did heavy diesel for about a decade before the career change. Good call averaging the diameter because the only other way to calculate that volume is with calculus. Great job explaining everything.
There are also crucible sizes that start with an A or a B instead of a #. Someone told me the A refers to weight in aluminum and the B refers to a bilge type crucible... You'd think it stood for brass, but maybe not? 😲 The plot thickens! I've heard a few conflicting explanations, perhaps sizing standards vary to some extent from one manufacturer to another. Well, at least the math for those PMC crucibles seems to fit the explanation they gave you. 👍
Thanks for the explanation, as for how much aluminium I need, I have CAD give me the volume say 1 litre and since that is equivalent to 1000cc I fill a measuring jug to the litre mark pour it into the crucible and make a mental note where I have to be above. Works for me Cheers Peter
Guess what. You have now broken the 100 subscribers list. I'm the guy who guessed a weight in #s and ounces. I think it was something like 4#s and 22ounces.I Lol
To calculate the volume of an irregular object, simply fill it with water to whatever level is "full" and then put that water in a known graduated cylinder.
Yeah, it does seem a volume measure would be more practical. The people over at PMC have bee very chatty, maybe I'll ask them why they the don't say 1 litre. They might tell me "we're in America and we spell it liter" Who knows :-D
I just recently had the same question about using my AutoCAD volume calcs to figure out how much aluminum I needed for a 3D printed model I designed. I found a simple in^3/lb of aluminum on EngineeringToolbox and did the math from there. Funny thing is I measured my #4 crucible, 3D modelled the inside, and got a total volume. I, coincidentally, decided 75% was a safe fill for a melt and came up with numbers VERY close to yours. The mystery was the #4-6. Now I know! If you ever want to crunch numbers like that again ask your friendly neighborhood plumbing engineer. I deal with this kind of mathy stuff every day. :D
Great video as always Perry! The safety factor you mention is called Freeboard in the foundry industry. Typically 70-80% capacity of the ladle/crucible. When are you opening your own aluminum foundry!?! 😁
As a Mariner, I totally get the Freeboard analogy. My question is... Is there a maximum/ most economical size of the crucible size to furnace volume ratio? I have a crucible that just fits inside the furnace, with just enough free space for the tongs. However, I am reluctant to use it because I feel there must be an optimum space for the "flame" to circulate, both for safety and economy of gas used. Another commenter alluded to this in the above comments, so I'm sure there are a few of us newbies that would appreciate your thoughts. Thanks, in advance for any thoughts you have.
@@leeii337 Let me start off with "I don't know". That said, the furnace I've been using for about three years has about 1/2" (12cm) distance between the crucible and the wall. The crucible naturally develops a hot spot where the flame blasts into it. This can be dealt with by rotating the crucible to a new position each time it is used but I never do. The tongs I had until last weekend simply made it impractical for me to turn the crucible in other directions. I don't know that this was a problem as my crucibles generally last a year or more. My new furnace has a ton of room between the furnace wall and the crucible. I have at least 2.5" (6cm) all around. I've yet to melt in it so I don't know how that will perform. Simple reasoning tells me that less volume to heat means less time to melt and that my old smaller furnace would melt metal sooner. I wanted more space for the tongs and the ability to use a larger crucible, hence the larger furnace.
I was gonna ask about your sand mix in the description section. Something along the line of how dry is your dry sand and how do you determine its dryness. Kidding. Lol Good info Perry, I think I'll stick with what someone else said. Just melt a lot more than what you'll need. All this reminds me of my geometry classes, still good to know if you need to. Thanks
Had been wondering about the numbers as I bought my first crucible and found out after it came it was almost too big for the furnace . Oops. Just have to build a bigger foundry furnace I reckon.
Been binge-watching? 😄😄 I was told years ago to buy your crucible first then build your furnace around it. I didn't listen and ended up building a furnace that was too tight. So, I built a bigger furnace 😄
They should standardize this whole system. Stick with kg, even though I'm American, I'm willing to compromise. Stick with a metal - copper is a common enough metal that is dense enough to make calculations on the fly or guesstimate (e.g. when melting brass or bronze). So e.g. a No. (#) 1 crucible should simply be the volume to fit one kg of copper.... a No. 10 should simply be the volume to fit ten kg of copper.
I agree, that would make things a lot easier. But I also know that if they did that some group would complain that that "they only melt aluminum" You wouldn't believe how many flipped out on this video because I divided two numbers. I even had a guy tell me I had lost him as subscriber because I did arithmetic in the video. Seriously. I can only imagine what would happen if you asked them to convert KG of copper to KG of aluminum.
Love your videos. Math melts my brains and im looking at getting started in this as a side hobby :) Hopefully i'll be able to work out the right ones i'll be needing to smelt 1kg ingots. keep up the videos
Sigh... I would have never guessed how many people would be derailed by some division but you’re in a large group. We don’t smelt, we melt. Smelting is what is done to extract metal from ore 😀
@@swdweeb S = Same size as last size diameter wise but taller to make up the volume! So I just bought a #10-S Which I guess is identical to a #8 in diameter! But 2 inches taller to make up a #10 volume! but yeah i messaged the company and got email this Moring lol! 🍺😜👍
So does that mean (in my instance I bought a #3-4kg crucible would I be able to use a3 lifting tongs? Im just confused why tongs they label crucibles a a# not ##)
I have no idea, but I did a little looking around and the measurements from pmc supplies indicate the #3-4K crucible is larger in diameter than their A3 crucible. My guess, and I emphasize GUESS, is that tongs for an A3 crucible would be too small for a #3-4KG crucible.
You know I went to the kitchen and got a large measuring cup. My crucible holds 8 cups of water comfortable fill level and 12 cups total. And the back side of the glass measure cup has metric.
Hello Sir.👋 Sir I am finding difficulty in melting steel.(As it melts at >1500°C) Its not becoming fluid or liquid.😣 So can you please tell me which "chemical or element" I can add to steel to lower its melting point. So that it can be easily melt at temperature
@@altamashansari8817 I got an answer that you're probably not going to like. I have a friend that runs a foundry here in the States. He told me what you need is more heat and that there is nota chemical you can add to lower the melting point. He said you can add phosphorus to iron to add fluidity but that you need to be careful how much you add. So, more heat is the answer.
No problem. And also Thank you Sir that you worked on my problem 😊 Is propane gas is enough to get much temperature to melt steel. Or should I use Acetylene gas for that. Or propane+oxygen gas.
@@swdweeb - I can do them but felt like a math class lecture. Lol. Was never a great student and taking notes is a weak skill for me. Doing it is better learning technique for me.
@@swdweeb Makes total sense. I am getting ready to start playing with this stuff as it looks like fun and a logical progression for my home shop. Thank you!
I've apologized a number of times for dividing two numbers in a video. I will never do that again, just as I will never fill my crucible full of water. The thought of drying it out without cracking it and ruining it is not something I'm interested in doing.
I would never fill my crucible with water. I guess if you want to go through a drying out period so it doesn't explode when you fire it the next time and think that's easier and faster than multiplying three numbers go for it.
no joke here, and not a criticism, but you have excellent videos with measurements I do not know and just viscerally reject. i deal in pounds and ounces, and at 57 i am beyond teaching or even wanting to be taught about metric measurements. i do not believe that metric is superior to English statute, but hey it is your channel, not mine. just know that you are either losing your audience or self-limiting your audience. would you be willing to include both metric and English statute measures? or are you just as inured to metric as I am to English?
This video stirred a lot of emotions when it first came out a little more than a year ago. A number of people were pretty upset that I divided two numbers, telling me "their heads exploded." The reality is there are two systems out there, imperial, what you call English, and metric. My videos are watched all over the world and the fact of the matter is we here in the States are the only country that is metric adverse. The crucibles that I buy are designated just the way I presented it , pounds of aluminum and kilograms of brass. That came from the manufacturer not me. If you prefer to work in fractions of an inch and fractions of pounds that's fine. I have no desire to try and convert anyone. For me, working in whole numbers is just easier. If you're opposed to learning then my channel isn't the one for you. I tend to put videos out that I think will teach people something. There are plenty of channels out there that simply melt metal and pour it into a ingot mold.
@@swdweeb It probably isn’t but my brain shuts down around math and number just like paper work I’m a normal functioning human then you hand me the paper work and my mind says screw this daaaa
dimensional analysis from back in physics 101 was the most useful thing I've ever learned and I have an engineering degree. i find it's easiest to write it out explicitly so you don't have to remember anything or do anything in your head
That make all the sense in the world now on how to get the correct crucible for your project and the number system used.
Thanks Lloyd
1. Place crucible on kitchen scale set to metric (grams).
2. Zero the scale.
3. Fill with water to a level you're comfortable with if it was holding molten metal.
4. Read kitchen scale. That's the (hopefully safe) usable volume of your crucible, in cubic centimeters. 1 gram of water = 1 c.c. = 1 mililiter
5. Be sure the crucible is dry before use.
I'm always amazed with the number of people that suggest filling my crucible, that is going in a 2000F furnace, with water and never mention the idea of thoroughly drying the crucible out before using it.
Just throw a bunch of metal in and eyeball it like BigD 🤣 haha thanks for explaining that to those that don’t know 👍🏻 well put buddy!
Ha!!! great example of what can go wrong. 😄😄
Thx Perry. I was always wondering the same thing! buying some crucible and hoping they are the right size. With this knowledge thats history!
I'm glad this was useful to someone. It seems a lot of people didn't find it useful or too complex.
@@swdweeb they don’t have to watch. 😂 it was very useful information and I liked the arithmetic as well! 😁
Complex shaped chambers are hard to calculate so physical measurement is fast and fairly accurate. Using bean bag beads, fill the chamber then pour them into a measuring jug. Measured a pool filter leaf basket, engine inlet manifold, hollow door and many others this way.
Trivia:
A cube of water with the sides of 10cm, it's 1 liter of volume and it weights 1kg.
So in the metric system we have distance, volume and weight all connected to each others 😃
Adding on, 0° Celsius is water freezing point and 100° C is water boiling point, all is linked to water 💧
I don't know how someone would prefer the imperial system over the simplicity and logic of the metric 😊
Well if we're going trivia wasn't a meter based on a fraction of the the distance between the north pole and the equator as it ran through Paris or something? Then they found out the number changed and the changed the length again and now its based on the distance light travels in some whacko number of time increments?
I do agree that having things tied together and based on 10 is a far simpler way to do things. I don't know that anyone will argue that calculating fractions of an inch is better or easier than counting
@@honthirty_ Now be nice.
You forgot to mention that those figures are all based on being at sea level. Things change when you go up a mountain or down in a submarine.
@@markfryer9880 Mark I love you, but I am amazed how proving the volume the volume of 6KG of brass is equivalent to 4 pounds of aluminum turned into the "volume of my crucible" as the main subject. Nearly 80% of the content of the video was based on defining the numbers on the product and proving them out, yet the sidetrack that I took at the end has turned into the main point that people have landed on. I am really amazed that people took such great offense (not you) at me multiplying three numbers to calculate the volume. It was almost as if I uttered the great blasphemy "how dare you ask us to do arithmetic!".
I realize that things change at different altitudes. That wasn't the point of the video, The point was are 6kg of brass equivalent to 4 pounds in aluminum? Yes they are.
Hey mate bigstackddd sent me over love the video's man. Keep it up.
Thanks for letting me know 😄
Great video. Even though I had to find this out on my own a long time ago. This should help anyone out that isn't afraid of numbers. To add to the thoughtful advice in the video. It's ok for customers to get product info from suppliers, and to check out details when they feel confused. Thanks 🙏 blessings to you.
Thank you Arik. I'm always a little surprised when someone tells me they stopped watching when I mentioned a number. It's crazy. It is alright to contact the manufacturer/supplier. Often times, not always, they readily provide the information.
@@swdweeb Of course the manufacturer as well.
Right shockingly disconcerting to get backlash for trying to help others. Generally it's because the individual is afraid of how little they know to learn anything new. It can have nothing to do with their intelligence but that they see themselves as not capable. A negative feedback loop brought on by anxiety, exacerbated from lack of actual social interaction. It's becoming more and more common as people lose themselves into social media platforms.
Great video, thanks for making it.
Went to the PCM website and it states the #6 is the weight in lbs of aluminum that the crucible holds, and the kg number is the kg of copper or brass it can hold. So a #8 - 10 kg will hold 8 lbs of aluminum, OR 10 kg of brass or copper.
Its funny, I got a comment on this video just a day or two ago where the guy started ranting about the stupid American measurement (his words not mine) . He even went so far as to say if computers were base 10 they would run faster. Guess he didn't understand the beauty and speed of arithmetic shifting. Sorry, I digress. It's amazing the comments this has generated. Everything from "when you divided two numbers my head exploded" to "just fill your crucible full of water"
I've just started getting into it, so far I've bought 3 crucibles, and I have been wondering myself, when you said I also was like, duh, how did I not see that
I guess its just another reason we all need to cut each other a little slack 😄 I assume you're referring to the "pound sign"?
@@swdweeb the pound sign... Correct
I actually really like your casual yet straight forward approach to your videos , I have actually learnt a lot here. Also as one that was looking at Petrabond thinking this is going to get expensive, you have made my day with your in depth discussion on the green sand. I'm going to definitely give this a go, Would of been interesting to see how a petrabond mould holds up to your latest batch of sand? Understandably the cost far out-ways the minimal benefit or loss to detail, but would have been a great comparison of detail using the same mould.
Thanks Jim. I actually thought about doing a comparison...briefly... but didn't have any new petrobond and didn't want to buy a batch just for one test. I'm hoping to get out and cast a few things today, maybe I can show some of the detail the new green sand picks up. Be a good way for me to advertise my sand again 😄 www.plmfoundries.com/product-page/green-sand
The good old days. Does anyone remember sitting in school saying " when will I ever need to know this"? Good stuff. I forget all the formulas I need sometimes and have to look them up but its satisfactory knowing how to read and calculate them
Yep, unfortunately some people never seem to grow out of "when will I ever need to know this stuff".
Thank you.
I appreciate the insight.
You're very welcome, thank you
Excellent video so informative! First crucible arrives today from Amazon.
Went to the same crucible dealer website you mentioned and got to confused with there blerb..changed website and payed to much..Doh!!!!thanks for the heads up video
I actually found that the 4mazon price is cheaper than buying direct from the supplier in this case. Weird. Happy melting 😄
Maybe I missed your reasoning for doing it the way you did but I would just fill it with Sand or BB's then pour that into a measuring cup to get the volume of the crucible?
Based on the number of similar comments I've received, I realize now that multiplying three numbers together to get the volume was an issue for a lot of people. My intent was to simply prove that the volumes calculated based on the weight of brass and aluminum were reasonable for the volume of the crucible. My sincerest apologies to all that were offended by the use of arithmetic during this video.
Another great video Sir..A lot of info in there! Wished I had it a week or so ago when I was casting that bronze slider and didn’t have enough bronze in my crucible!
Thanks bud. I've got some larger pieces in mind and I'm hopeful it'll keep me from underrunning the part
@@swdweeb trust me!!! It’s way better to have to much than not enough
Great info Perry. I have baught a few from PMC too. A lot of the crucibles actually explain that in the description, thats how I first figured it out. Thanks for the info on how to figure out the volume.
I've never seen it on the crucibles I buy.
Thank you for doing the hard work for us. But now I can say I know what the numbers mean.
Thanks, it was fun finding out... as I said, only took me 3 years 😄
A much simpler way is to multiply the # of the crucible by 10 to get the volume in cubic inches. A #12 crucible is 120 cubic inches, aluminum weighs .1 lbs per cubic inch.
Great info to know! I’ve just been ordering 8kg crucibles because my furnace holds a 10kg, and I like having the extra room for my lifters 😁
That's one of the big reasons I built my new furnace. Wanted to make sure I could get my tongs in around the crucible.
👍👍👍👍👍
Thanks
Now I Know and knowing is half the battle. Thanks for sharing!
Thanks Craig
Great video and really good info to know!
Glad it was helpful!
I have a simpler method. Measure the weight of the crucible, fill the crucible to the top with water, measure the weight of the crucible and water, then subtract the crucible's weight from the combined weight to get the weight of the water. If your measurements are in grams, then the weight of the water is the volume of the crucible in cc's. It eliminates the protracted calculations, and is more accurate than estimating the diameters, depths, etc which introduce errors. Now if you want to know the volume you can pour, then fill the crucible about 80%, or whatever volume of molten metal you feel comfortable having in the crucible and do the same procedure with the crucible partially full. Just remember to dry your crucible in an oven to eliminate all the moisture before using it for a melt.
FYI: I have purchased crucibles online and the physical size of the crucible can vary from one manufacturer to another. One manufacturer's 8 kg crucible is another's 10 kg. Stick with the Morgan crucibles to determine the size. Take the Morgan crucible dimensions and compare the dimensions of the crucible you are purchasing to determine a reliable kg weight for the crucible. I have seen crucibles of the same dimensions listed as 8 kg, 9 kg, & 10 kg. It is for selling purposes. I am guessing that the 8 kg actually represents the weight a 80% full, 9 kg - 90%, and 10 kg - 100%. I don't know anyone who would do a melt to fill 100% of the crucible, 90% is a push. Personally I am comfortable with 80%.
Bottom line, I don't generally work with the weight of metal when casting an item, I am concerned with the volume because the same part is going to require the same volume regardless of the metal being used.
You forgot the step of drying your crucible thoroughly so it doesn’t break or explode when you heat it. I’d never fill my crucibles with water but I’m just weird.
I’ve never been concerned with the weight either but three or four years ago when I made that video a few people had asked what the numbers meant.
Another great video! Conversion can sure mess with your head for sure! I have had some odd shaped containers to use for melting and being that calculation would be too complex, I filled with water and poured into a measuring container. Your method is far better for sure and with a bit more volume than you need for a piece, you can cover the extra material needed for the in and out holes :) Thanks for this, I found it enriching!
Thanks, I'm glad it helped. 😄
Well that cleared that up, it was worth the pain in my head
I know multiplication and division can be tough, sorry
AH yes # Pound gives a new dimension to the whole #me2 thing 😂
Weird they use an alloy for a measurement, it can vary depending on the ratio
Thanks for this science lesson, I learned something today 😋👊👍
Yeah, there are all sorts of things in this world that are the way they are because that's how we've always done it 😄
Glad you got something out of it.
BigstackD sent me here Perry. Hoping to learn a lot from you.
No pressure them right? 😄😄 Welcome, I hope you do as well. Thanks for letting me know
@@swdweeb no pressure, gotta be a step ahead of my boy which wants to get into it as well.
Same here!
Awesome video and great explanation. I got what I needed when you said pounds and kilograms but you were having way too much fun with the density calculations so I kept watching. Lol. I am an aerospace engineering major that did heavy diesel for about a decade before the career change. Good call averaging the diameter because the only other way to calculate that volume is with calculus. Great job explaining everything.
Thank you so much. When I originally posted that video I had a number of people complain because I talked about dividing two numbers. It was surreal
Or use water in a measuring cup?
@@drdean1996 You can’t calculate with a measuring cup. Lol
There are also crucible sizes that start with an A or a B instead of a #. Someone told me the A refers to weight in aluminum and the B refers to a bilge type crucible... You'd think it stood for brass, but maybe not? 😲 The plot thickens! I've heard a few conflicting explanations, perhaps sizing standards vary to some extent from one manufacturer to another. Well, at least the math for those PMC crucibles seems to fit the explanation they gave you. 👍
Yeah, I know, I've seen the lettered crucibles as well. It's almost like the casting world just comes up with stuff willy nilly 😄😄
Thanks for the explanation, as for how much aluminium I need, I have CAD give me the volume say 1 litre and since that is equivalent to 1000cc I fill a measuring jug to the litre mark pour it into the crucible and make a mental note where I have to be above. Works for me
Cheers
Peter
You're welcome
Thought it was a pound. Mind blown thank you for the content
You were right then. 😄
👍👍😎👍👍 - great info - thank you
Glad it was helpful!
Someone just filled me in on this in the last few months! I couldn't figure it out myself either for the longest time.
Man you should have done a video and spared me the trouble 😄😄
@@swdweeb nah I have 99 subs, you have 6k, much more ppl will see it now instead! :)
@@ChatterontheWire Fair enough. I've only lost one sub since it came out 😄😄
Guess what. You have now broken the 100 subscribers list.
I'm the guy who guessed a weight in #s and ounces. I think it was something like 4#s and 22ounces.I
Lol
To calculate the volume of an irregular object, simply fill it with water to whatever level is "full" and then put that water in a known graduated cylinder.
I would never fill my crucible with water. The effort to thoroughly dry it out before heating is far greater than some simple arithmetic.
Its strange they still put kg of brass on them still, a volume is much more useful when 3d modelling.
Yeah, it does seem a volume measure would be more practical. The people over at PMC have bee very chatty, maybe I'll ask them why they the don't say 1 litre. They might tell me "we're in America and we spell it liter" Who knows :-D
A little tongue twister today. It was great!
Yes, just another case of the brain not working as fast as the mouth 😄
Well done on that math assignment. :) Really hitting home with me right now as I am helping my youngest daughter with her college chemistry.
😄 Good that you can actually do that
I just recently had the same question about using my AutoCAD volume calcs to figure out how much aluminum I needed for a 3D printed model I designed. I found a simple in^3/lb of aluminum on EngineeringToolbox and did the math from there.
Funny thing is I measured my #4 crucible, 3D modelled the inside, and got a total volume. I, coincidentally, decided 75% was a safe fill for a melt and came up with numbers VERY close to yours.
The mystery was the #4-6. Now I know!
If you ever want to crunch numbers like that again ask your friendly neighborhood plumbing engineer. I deal with this kind of mathy stuff every day. :D
Ha. Ok. I'll remember that. I do try to limit the number of people I expose my lack of math skills to 😄😄
Great video as always Perry! The safety factor you mention is called Freeboard in the foundry industry. Typically 70-80% capacity of the ladle/crucible. When are you opening your own aluminum foundry!?! 😁
Ha! I'd love to.
As a Mariner, I totally get the Freeboard analogy.
My question is...
Is there a maximum/ most economical size of the crucible size to furnace volume ratio?
I have a crucible that just fits inside the furnace, with just enough free space for the tongs. However, I am reluctant to use it because I feel there must be an optimum space for the "flame" to circulate, both for safety and economy of gas used.
Another commenter alluded to this in the above comments, so I'm sure there are a few of us newbies that would appreciate your thoughts.
Thanks, in advance for any thoughts you have.
@@leeii337 Let me start off with "I don't know".
That said, the furnace I've been using for about three years has about 1/2" (12cm) distance between the crucible and the wall. The crucible naturally develops a hot spot where the flame blasts into it. This can be dealt with by rotating the crucible to a new position each time it is used but I never do. The tongs I had until last weekend simply made it impractical for me to turn the crucible in other directions. I don't know that this was a problem as my crucibles generally last a year or more.
My new furnace has a ton of room between the furnace wall and the crucible. I have at least 2.5" (6cm) all around. I've yet to melt in it so I don't know how that will perform. Simple reasoning tells me that less volume to heat means less time to melt and that my old smaller furnace would melt metal sooner.
I wanted more space for the tongs and the ability to use a larger crucible, hence the larger furnace.
Great video Perry, you did all the math :) I think I use no 3 crucibles in my small furnace then :)
yeah, and I got several people mad at me for doing arithmetic in the video. Seems multiplying three numbers together was too much for some people. 😄
I was gonna ask about your sand mix in the description section. Something along the line of how dry is your dry sand and how do you determine its dryness. Kidding. Lol
Good info Perry, I think I'll stick with what someone else said. Just melt a lot more than what you'll need.
All this reminds me of my geometry classes, still good to know if you need to.
Thanks
The point wasnt to know... oh never mind.
I never knew what the numbers meant! Now I do, but will I remember it when I need it??
Probably don't need to remember 😄 All you have to remember is "is the same one I bought last time?"
Had been wondering about the numbers as I bought my first crucible and found out after it came it was almost too big for the furnace . Oops. Just have to build a bigger foundry furnace I reckon.
Been binge-watching? 😄😄 I was told years ago to buy your crucible first then build your furnace around it. I didn't listen and ended up building a furnace that was too tight. So, I built a bigger furnace 😄
This was great!
Thank you John. I'm glad you appreciated it. You're in the minority 😄
They should standardize this whole system. Stick with kg, even though I'm American, I'm willing to compromise. Stick with a metal - copper is a common enough metal that is dense enough to make calculations on the fly or guesstimate (e.g. when melting brass or bronze). So e.g. a No. (#) 1 crucible should simply be the volume to fit one kg of copper.... a No. 10 should simply be the volume to fit ten kg of copper.
I agree, that would make things a lot easier. But I also know that if they did that some group would complain that that "they only melt aluminum" You wouldn't believe how many flipped out on this video because I divided two numbers. I even had a guy tell me I had lost him as subscriber because I did arithmetic in the video. Seriously.
I can only imagine what would happen if you asked them to convert KG of copper to KG of aluminum.
Love your videos. Math melts my brains and im looking at getting started in this as a side hobby :) Hopefully i'll be able to work out the right ones i'll be needing to smelt 1kg ingots. keep up the videos
Sigh... I would have never guessed how many people would be derailed by some division but you’re in a large group.
We don’t smelt, we melt. Smelting is what is done to extract metal from ore 😀
@@swdweeb I would bet after working in all that heat you smelt. :)
very nice video man! good work!
Thanks
@@swdweeb so.... what's the s mean on one of these lol! One bought today was #10S #10 looked nearly identical lol any ideas?
@@BuildBreakFix A quick internet search turns up... nothing 😄 I have no idea. Maybe reach out to the manufacturer and see if they'll tell you.
@@swdweeb S = Same size as last size diameter wise but taller to make up the volume! So I just bought a #10-S Which I guess is identical to a #8 in diameter! But 2 inches taller to make up a #10 volume! but yeah i messaged the company and got email this Moring lol! 🍺😜👍
So does that mean (in my instance I bought a #3-4kg crucible would I be able to use a3 lifting tongs? Im just confused why tongs they label crucibles a a# not ##)
I have no idea, but I did a little looking around and the measurements from pmc supplies indicate the #3-4K crucible is larger in diameter than their A3 crucible. My guess, and I emphasize GUESS, is that tongs for an A3 crucible would be too small for a #3-4KG crucible.
You know I went to the kitchen and got a large measuring cup. My crucible holds 8 cups of water comfortable fill level and 12 cups total. And the back side of the glass measure cup has metric.
Cool, I never fill my crucible with water but more power to you
@@swdweeb Yeah, let it dry for week. And slowly heat it for a while. Flash steam is bad.
This is interesting... thank you...
You're welcome 😄
Whatup new friend, great info!
thanks
BigstackD sent me big thanks for your knowledge
Thanks for your note and thanks for letting me know he sent you. I appreciate it.
Let me try one other avenue for you.
Awesome tongue twister. Thumbs up from a small creator 😅
😁
Hello Sir.👋
Sir I am finding difficulty in melting steel.(As it melts at >1500°C)
Its not becoming fluid or liquid.😣
So can you please tell me which "chemical or element" I can add to steel to lower its melting point.
So that it can be easily melt at temperature
I'm sorry, I do not know. I would reach out to @luckygen1001 and ask him. He routinely melts iron and might have knowledge of steel.
No problem.😊
I had also asked from @luckygen1001. He hadn't replied yet.
@@altamashansari8817 I got an answer that you're probably not going to like. I have a friend that runs a foundry here in the States. He told me what you need is more heat and that there is nota chemical you can add to lower the melting point. He said you can add phosphorus to iron to add fluidity but that you need to be careful how much you add. So, more heat is the answer.
No problem.
And also Thank you Sir that you worked on my problem 😊
Is propane gas is enough to get much temperature to melt steel.
Or should I use Acetylene gas for that.
Or propane+oxygen gas.
Maths are too hard...
Good video.
Tell me you're joking
@@swdweeb - I can do them but felt like a math class lecture. Lol. Was never a great student and taking notes is a weak skill for me. Doing it is better learning technique for me.
1kg = 2.2lb. 4lb to 6kg doesn't add up. Am I missing something?
Yes, you're missing the specific gravity. Aluminum is nowhere near as dense as brass
Thank you
Why not fill it with water first, then pour the water into a measuring cup... just an idea..
Because I'd have to go through the process of drying the thing out again before I could safely use it
@@swdweeb Makes total sense. I am getting ready to start playing with this stuff as it looks like fun and a logical progression for my home shop. Thank you!
Just put the container on a scale, zero it, then fill it to volume with water. 1 gram = 1 cc
I've apologized a number of times for dividing two numbers in a video. I will never do that again, just as I will never fill my crucible full of water. The thought of drying it out without cracking it and ruining it is not something I'm interested in doing.
Hello Sir..my name is Abbas..from Malaysia..
Hello
Alot of math there for me lol just put enough in there and go for it lol
Yeah, that high-powered arithmetic gets to some people
I would measure the amount of water the crucible holds. Sounds like easier math.
I would never fill my crucible with water. I guess if you want to go through a drying out period so it doesn't explode when you fire it the next time and think that's easier and faster than multiplying three numbers go for it.
Maybe something dry like rice or wheat? Would give a good idea without soaking the crucible.
Those plastic yellow BBs would work too 👍
@@swdweeb good point! Never thought of that :-)
@@swdweeb
Dry sand
I didn't know. Im from other side on world hehe
Don't tell me you live in one of those places that abandoned imperial units of measure 🤣
Perry, I think that your measures for a gram of water are wrong.
What did I say, a cubic centimeter right? That's a milliliter.
en.wikipedia.org/wiki/Cubic_centimetre
no joke here, and not a criticism, but you have excellent videos with measurements I do not know and just viscerally reject. i deal in pounds and ounces, and at 57 i am beyond teaching or even wanting to be taught about metric measurements. i do not believe that metric is superior to English statute, but hey it is your channel, not mine. just know that you are either losing your audience or self-limiting your audience. would you be willing to include both metric and English statute measures? or are you just as inured to metric as I am to English?
This video stirred a lot of emotions when it first came out a little more than a year ago. A number of people were pretty upset that I divided two numbers, telling me "their heads exploded." The reality is there are two systems out there, imperial, what you call English, and metric. My videos are watched all over the world and the fact of the matter is we here in the States are the only country that is metric adverse. The crucibles that I buy are designated just the way I presented it , pounds of aluminum and kilograms of brass. That came from the manufacturer not me.
If you prefer to work in fractions of an inch and fractions of pounds that's fine. I have no desire to try and convert anyone. For me, working in whole numbers is just easier.
If you're opposed to learning then my channel isn't the one for you. I tend to put videos out that I think will teach people something. There are plenty of channels out there that simply melt metal and pour it into a ingot mold.
1st!!!
Yay for you bud!
Interesting but you lost me at the math and all the numbers lol makes my brain hurt
I will just stick with melting more than I need lol
Oh come on. Surely that wasn't too complex for you.
@@swdweeb
It probably isn’t but my brain shuts down around math and number just like paper work
I’m a normal functioning human then you hand me the paper work and my mind says screw this daaaa