what size crucible is good?

[dogdog]

Trying to build a smelting furnace out of an old 40-gallon water heater core.... So never done it before,... what is a good size crucible to buy? I needed to plan out the furnace hole size... But when I looked up a crucible, they come in #x size or kg format .... Not sure what that means... anyone can decipher that for me what they mean?


Just needed it to cast a few parts, or at least trying to and learn something in the process..

 

[dogdog]

https://www.ebay.com/sch/i.html?_fr...A0.H0.Xcrucible+.TRS0&_nkw=crucible+&_sacat=0

 

[hawkeye2]

http://www.budgetcastingsupply.com/mobile/Product.aspx?id=37575

 

[PAToyota]

what is a good size crucible to buy?

About 25% more volume than what you're casting is a good start.

 

[dogdog]

No idea what that means...
so the KG or LBs rating on that crucible means it is the volume or is it the weight of the material? or is that the weight of the crucible ?

Doesn't make sense since material different by weight from alumnium/copper/bronze/iron/gold etc.. and volume doesn't go by kg/lbs.....

So far the link provided by hawkeye2 says there are different shapes.. but that link doesn't provide enough details...

 

[Gizmosity]

casting materials are a commodity. They are sold by weight. When talking about castings, weights are used. Similarly, crucibles are based on weight capacity, in the case of the link, 6kg. of brass.

 

[hawkeye2]

The link I posted above provides dimensions and weight of different materials they hold.

 

[PAToyota]

No idea what that means...

The eBay listings typically are giving dimensions and/or weight of a material (from which you can calculate volume). Figure out the volume you need, add 1/4 more, and get a crucible that will hold that volume.

 

[dogdog]

Being the first time building this, I don't know what volume I needed, so that is why I am asking what is a common size...#3 #4 #5 etc ?... the furnace I am going to use sodium silicate / and perlite. cheap enough to do. I have the two Reil style burner... that is good... Just not sure what is a good common size and type of crucible or tongs I needed.... This is not for business, just a DIY casting of few things I needed.

 

[R.Anderson]

Being the first time building this, I don't know what volume I needed, so that is why I am asking what is a common size...#3 #4 #5 etc ?... the furnace I am going to use sodium silicate / and perlite. cheap enough to do. I have the two Reil style burner... that is good... Just not sure what is a good common size and type of crucible or tongs I needed.... This is not for business, just a DIY casting of few things I needed.

Well for the parts you need figure out the volume needed for the largest part and like stated add 25% Only you can really answer your question.

What are ya planning on casting? Aluminum, iron, brass, copper, etc. Different metals shrink more than others.

What method of casting? Green sand, lost foam, investment, etc. This matters with how you make the mold cavity which will vary the volume needed.

http://www.backyardmetalcasting.com/
http://www.themetalcasting.com/hobby-foundry.html

There are few good sites out there for this exact subject that will help you out.

 

[Lelandwelds]

Being the first time building this, I don't know what volume I needed, so that is why I am asking what is a common size...#3 #4 #5 etc ?... the furnace I am going to use sodium silicate / and perlite. cheap enough to do. I have the two Reil style burner... that is good... Just not sure what is a good common size and type of crucible or tongs I needed.... This is not for business, just a DIY casting of few things I needed.

You don't know the size of the things you need? Who does? Is it bigger than a breadbox? Can you wear it around your finger?

Casting, forging, etc. is noisy, messy, and hot work anyway. Maybe you should pursue another hobby.

 

[PAToyota]

so that is why I am asking what is a common size...#3 #4 #5 etc ?

Well for the parts you need figure out the volume needed for the largest part and like stated add 25% Only you can really answer your question.

Pretty much this. A "good size" crucible for casting a couple rings or other jewelry is not going to be a "good size" for casting a door knocker or a door stop.

"Common sizes" go from small to large.

 

[dogdog]

You don't know the size of the things you need? Who does? Is it bigger than a breadbox? Can you wear it around your finger?

Casting, forging, etc. is noisy, messy, and hot work anyway. Maybe you should pursue another hobby.

Trying to figure out/planning a furnace so it can accommodate a good size crucible(s). Not how to calculate the volume of material needed on this thread.

 

[dogdog]

Well for the parts you need figure out the volume needed for the largest part and like stated add 25% Only you can really answer your question.

What are ya planning on casting? Aluminum, iron, brass, copper, etc. Different metals shrink more than others.

What method of casting? Green sand, lost foam, investment, etc. This matters with how you make the mold cavity which will vary the volume needed.

http://www.backyardmetalcasting.com/
http://www.themetalcasting.com/hobby-foundry.html

There are few good sites out there for this exact subject that will help you out.

Thanks, I'll check those two links out

 

[PAToyota]

Trying to figure out/planning a furnace so it can accommodate a good size crucible(s). Not how to calculate the volume of material needed on this thread.

The volume of material dictates the size of the crucible to melt it in, which then dictates the size of the furnace to fit the crucible...

If you're trying to figure out the size of the furnace, I'd probably at least go double the size of the volume of material I thought I needed. You can always buy a bigger crucible, but building a bigger furnace is much more work.

 

[01-7700]

Buy the biggest crucible you can fit in your already determined furnace size. Fill it with enough material to complete the project at hand.

 

[dogdog]

.........

If you're trying to figure out the size of the furnace, I'd probably at least go double the size of the volume of material I thought I needed. You can always buy a bigger crucible, but building a bigger furnace is much more work.

Yes trying to figure out a size I would need, just a question out there to see what is common... I am eyeing on that #3 7kg or #4 10Kg one... and maybe a smaller size one for a smaller part. I don't want to build a one off for just this part, a coffee can forge would have done this one .... which is small. wanted one that can anticipate

Buy the biggest crucible you can fit in your already determined furnace size. Fill it with enough material to complete the project at hand.

Yea I haven't built the furnace, sort of stuck....in this loop... that is why the question... I think a 10" chamber should be good?

 

[PAToyota]

Yes trying to figure out a size I would need, just a question out there to see what is common.

Until you figure out what YOU are going to cast, you'll continue to spin your wheels.

A common size crucible for jewelry making is going to be much different from a common size for tool making is going to be much different from a common size for heavy equipment parts.

It's like you're asking how big a pot you need to make soup. Well, are you making soup for yourself, your family of four, or the family reunion of sixty people?

 

[dogdog]

Until you figure out what YOU are going to cast, you'll continue to spin your wheels.

A common size crucible for jewelry making is going to be much different from a common size for tool making is going to be much different from a common size for heavy equipment parts.

It's like you're asking how big a pot you need to make soup. Well, are you making soup for yourself, your family of four, or the family reunion of sixty people?

Yea, I got what you mean, I'll just go with one and "upgrade from there then" thanks.

 

[OccupantRJ]

Go on YouTube and look for myfordboy. He has lots of casting videos. See what he is casting. Contact him and ask about cask sizes he uses.