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Author Topic: Aluminum melting  (Read 10818 times)

Offline unfy

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Re: Aluminum melting
« Reply #60 on: October 08, 2016, 07:49:13 PM »
Was doing a gentle re-heat of the furnace today so can possibly get some melting in tomorrow.  With all the rain and humidity, figure'd it be a good idea.  Seems like it was - saw some steam and then detected presence of invisible steam later.

Since the furnace was gonna be hot even on 'gentle', went ahead and attempted a melt.

Earlier, had built some sand boxes out of some 1x2's, 1x4's, and cheap "plywood".  In case of an accident, molten metal on concrete or black top is a no-no, etc.

Using another cut up MAP gas bottle as a crucible, the melt went fine.  After lifting crucible out and cleaning up the dross - it failed at the 'webbing'.  The melt went pretty quick even on 'low' and the furnace and burner did nicely.  I'm happy.

Tomorrow I'll look into getting some 3/16" rod bent up for "tongs" on a real crucible I snagged off ebay.

hoppe's #9 is not the end all be all woman catching pheramone people make it out to be ... cause i smell of it 2 or 3 times a week but remain single  >:D

Offline unfy

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Re: Aluminum melting
« Reply #61 on: November 20, 2016, 08:49:45 PM »
Spent Sat and Sun working on finishing off the can pile.

After a 30-40gal trashcan of crushed cans, and a fair amount of uncrushed cans... I have around 18lb of aluminum ingots.

Some home made crucible tongs worked out nicely.  Two 1/8" x 1" x 36" weldable flat boars from hardware store.  Two bits of 1 or 1-1/8" angle iron about 1" long each.  Some 1/4 or 3/16 (i forget) round stock (also weldable), and an 1" x 18" black iron pipe cut in half to act as handles.



Q & A:

Q) Was working with cans worth it ?

A) Not really. 

It's slow to fill the pot - costing you money in fuel and trying your patience. 

It produces a lot of waste. 

The alloy that makes up cans (ABC or something... american beverage can ?) is not great for casting other things.

Because of trying to gently push cans down into the molten metal / crucible, you're also putting un-needed pressure on the crucible.



Q) Charcoal or propane ?

A) For me, propane.

Charcoal was interesting for seeing what I thought of the process, but propane is just cleaner and less fuss.  It's also cheaper, I think.

Building the burner will take a tiny amount of time, or buying a burner will add a bit of cost - but if you're gonna play with this, might as well just accept these things.

Being able to simply start the furnace and not have to play with charcoal management is a huge benefit.  Also not dealing with charcoal dust is really nice.

I dunno if forced air charcoal can be made to run hotter or not.  Waste oil burners are a valid 'thing' for running hotter, though.



Q) Opinions on the cheap burner made from hardware store stuff ?

A) Works fine for me.  During actual melts I've had no blow outs or any other issues.  I dunno if some flaps for chokes would be of benefit or not.



Q) Bought crucible or home made ?

A) For me, bought.

Food cans really didn't work out well when melting pop cans.  With chunkier source material, it might do okay... I dunno.

Propane bottles really seemed like they wanted to work, but I never had any luck.  Again, using better source metal (not cans) might make them far more viable for a few melts.  The whole 'press the can down into the pool' really seems to hurt things.

Exhaust pipe did somewhat okay... but not terribly great either.  Again - better source material might make all the difference...

Notice a pattern of not liking cans ? :D

Never tried a fire extinguisher.

Never got to try some 1/4" wall pipe or other thick pipe stuff.

I had bought a 'salamander' A shaped crucible.  Fabricated up some lifting tongs.  I'm really happy with it.  3 or 4 melts with no problems what so ever.



Q) Thoughts on the furnace

A) I approve.  It's inexpensive, fun to do/learn-to-do, and works.  And relatively inexpensive. Make your own!

A more round burn chamber would be nice heh.  A slightly larger burn chamber would also be nice to better fit the crucible I have (squeezing the lifting tongs in it is a chore).

I would possibly suggest some kind of more / better re-enforcement inside of it.  I have plenty of screws sticking in from the handles and seems - which the furnace body seems generally okay.  The lid, however, does have a crack or two in it that makes me 'hmmmm' to myself.

hoppe's #9 is not the end all be all woman catching pheramone people make it out to be ... cause i smell of it 2 or 3 times a week but remain single  >:D

Offline Les

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Re: Aluminum melting
« Reply #62 on: November 20, 2016, 08:58:13 PM »
Spent Sat and Sun working on finishing off the can pile.

After a 30-40gal trashcan of crushed cans, and a fair amount of uncrushed cans... I have around 18lb of aluminum ingots.

Some home made crucible tongs worked out nicely.  Two 1/8" x 1" x 36" weldable flat boars from hardware store.  Two bits of 1 or 1-1/8" angle iron about 1" long each.  Some 1/4 or 3/16 (i forget) round stock (also weldable), and an 1" x 18" black iron pipe cut in half to act as handles.

Q & A:

Q) Was working with cans worth it ?

A) Not really. 

It's slow to fill the pot - costing you money in fuel and trying your patience. 

It produces a lot of waste. 

The alloy that makes up cans (ABC or something... american beverage can ?) is not great for casting other things.

Because of trying to gently push cans down into the molten metal / crucible, you're also putting un-needed pressure on the crucible.



Q) Charcoal or propane ?

A) For me, propane.

Charcoal was interesting for seeing what I thought of the process, but propane is just cleaner and less fuss.  It's also cheaper, I think.

Building the burner will take a tiny amount of time, or buying a burner will add a bit of cost - but if you're gonna play with this, might as well just accept these things.

Being able to simply start the furnace and not have to play with charcoal management is a huge benefit.  Also not dealing with charcoal dust is really nice.

I dunno if forced air charcoal can be made to run hotter or not.  Waste oil burners are a valid 'thing' for running hotter, though.



Q) Opinions on the cheap burner made from hardware store stuff ?

A) Works fine for me.  During actual melts I've had no blow outs or any other issues.  I dunno if some flaps for chokes would be of benefit or not.



Q) Bought crucible or home made ?

A) For me, bought.

Food cans really didn't work out well when melting pop cans.  With chunkier source material, it might do okay... I dunno.

Propane bottles really seemed like they wanted to work, but I never had any luck.  Again, using better source metal (not cans) might make them far more viable for a few melts.  The whole 'press the can down into the pool' really seems to hurt things.

Exhaust pipe did somewhat okay... but not terribly great either.  Again - better source material might make all the difference...

Notice a pattern of not liking cans ? :D

Never tried a fire extinguisher.

Never got to try some 1/4" wall pipe or other thick pipe stuff.

I had bought a 'salamander' A shaped crucible.  Fabricated up some lifting tongs.  I'm really happy with it.  3 or 4 melts with no problems what so ever.



Q) Thoughts on the furnace

A) I approve.  It's inexpensive, fun to do/learn-to-do, and works.  And relatively inexpensive. Make your own!

A more round burn chamber would be nice heh.  A slightly larger burn chamber would also be nice to better fit the crucible I have (squeezing the lifting tongs in it is a chore).

I would possibly suggest some kind of more / better re-enforcement inside of it.  I have plenty of screws sticking in from the handles and seems - which the furnace body seems generally okay.  The lid, however, does have a crack or two in it that makes me 'hmmmm' to myself.
« Last Edit: November 20, 2016, 09:02:53 PM by Les »

Offline Les

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Re: Aluminum melting
« Reply #63 on: November 20, 2016, 09:04:37 PM »

Offline unfy

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Re: Aluminum melting
« Reply #64 on: November 20, 2016, 10:05:15 PM »
Can you melt AL alloy?

That's what this thread has been about :D.

Yes - I've been making some aluminum muffins. It's been a neat learning experience.
hoppe's #9 is not the end all be all woman catching pheramone people make it out to be ... cause i smell of it 2 or 3 times a week but remain single  >:D

Offline Les

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Re: Aluminum melting
« Reply #65 on: November 21, 2016, 07:09:34 AM »
Sorry guess I misspoke, meant to say cast Al. 

Offline unfy

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Re: Aluminum melting
« Reply #66 on: November 22, 2016, 02:39:44 AM »
I have yet to do any useful casting.  Been mostly just ingot-izing a pile of cans.

I'll be grabbing a thrift store coffee grinder or food processor to grind up some cat litter as a bentonite clay source for green sand.  Will also be making my own flasks real soon now, too.

After that, I'm free to play with trying to cast useful objects.  Whatever those may be - I've got no plans for anything as of yet heh.

Wonder if using some silicone or plaster and other stuff in order to make a pattern or something for duplicating an object... or... I dunno.  *shrug*.  Sadly, a lot of the 'useful' objects ya might wanna make would usually require further machining - which I don't have the capacity to do at the moment :(.  Artsy stuff I can prolly do... but I am not an artist :D



hoppe's #9 is not the end all be all woman catching pheramone people make it out to be ... cause i smell of it 2 or 3 times a week but remain single  >:D

Offline Les

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Re: Aluminum melting
« Reply #67 on: November 22, 2016, 06:56:07 AM »
I have yet to do any useful casting.  Been mostly just ingot-izing a pile of cans.

I'll be grabbing a thrift store coffee grinder or food processor to grind up some cat litter as a bentonite clay source for green sand.  Will also be making my own flasks real soon now, too.

After that, I'm free to play with trying to cast useful objects.  Whatever those may be - I've got no plans for anything as of yet heh.

Wonder if using some silicone or plaster and other stuff in order to make a pattern or something for duplicating an object... or... I dunno.  *shrug*.  Sadly, a lot of the 'useful' objects ya might wanna make would usually require further machining - which I don't have the capacity to do at the moment :(.  Artsy stuff I can prolly do... but I am not an artist :D
The reason I'm curious about cast is I have some cast aluminum pole bases and aluminum poles (5" if memory serves) I was planning on scrapping but wondered if they can be melted down for a usefull purpose.

Offline m morton

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Re: Aluminum melting
« Reply #68 on: November 22, 2016, 01:09:07 PM »
i did some casting back in school using forms and that sticky oil sand . place an object face up , put the sand on top of it and tamp the sand as you add more and more till the form is full "the forms should not have smooth in side surface" or the sand will not hold to the inside of the form and fall out while flipping them over etc..  ,once full you strike a clean flat top so it can be flipped over, place another form on top fill another form from the back , filling and tamping the sand the form should have a pins or rods to keep them from moving apart or side to side. then after both are filled you separate the 2 forms remove the item being duplicated. and make fill and vent holes plus cut out flow notches to the fill and vent holes . once the aluminum is melted pore it in to the fill and vent holes . allow to cool and remove the cast and dump the sand in a storage ben to be used again.

once the cast is cool to the touch you use a saw to remove the notches and fill hole excess and a file to smooth it to look as it should. i did a few items and i should still have them in a box in storage. was fun projects back in metals class in Jr. high. back in the late 70's

FYI the tacky sand will smoke, so do it in a well vented area ! the sand is reusable till too much of the tacky oil is burned off the sand from the hot aluminum, when that happens the casting will be harder as the sand will not pack as good and crumbles and the vent and fill holes and cast will cave in. not sure if the metals teacher added more tacky oil to the sand or replaced the sand all together ??? sorry never seen him do either . i just know the oil sand started out black & tacky and when it was dark gray it did not work as good and soon after the storage ben sand was black again...

that's what i remember from back then
ever want to try and would like my novice help i live in west Omaha and would need a ride
I will allow myself one personal observation. If you want to disarm yourself, that is your choice. The following quote is a favorite of mine and something to keep in mind when you make that choice.

“Sheep don’t tell wolves what’s for dinner.”

Offline unfy

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Re: Aluminum melting
« Reply #69 on: November 22, 2016, 03:07:42 PM »
i did some casting back in school using forms and that sticky oil sand . place an object face up , put the sand on top of it and tamp the sand as you add more and more till the form is full "the forms should not have smooth in side surface" or the sand will not hold to the inside of the form and fall out while flipping them over etc..  ,once full you strike a clean flat top so it can be flipped over, place another form on top fill another form from the back , filling and tamping the sand the form should have a pins or rods to keep them from moving apart or side to side. then after both are filled you separate the 2 forms remove the item being duplicated. and make fill and vent holes plus cut out flow notches to the fill and vent holes . once the aluminum is melted pore it in to the fill and vent holes . allow to cool and remove the cast and dump the sand in a storage ben to be used again.

once the cast is cool to the touch you use a saw to remove the notches and fill hole excess and a file to smooth it to look as it should. i did a few items and i should still have them in a box in storage. was fun projects back in metals class in Jr. high. back in the late 70's

FYI the tacky sand will smoke, so do it in a well vented area ! the sand is reusable till too much of the tacky oil is burned off the sand from the hot aluminum, when that happens the casting will be harder as the sand will not pack as good and crumbles and the vent and fill holes and cast will cave in. not sure if the metals teacher added more tacky oil to the sand or replaced the sand all together ??? sorry never seen him do either . i just know the oil sand started out black & tacky and when it was dark gray it did not work as good and soon after the storage ben sand was black again...

that's what i remember from back then
ever want to try and would like my novice help i live in west Omaha and would need a ride

This.

That is the process in a nutshell.

I won't be using petrobond (oil bonded sand) - but rather a mix of bentonite clay and sand (aka greensand).  It can't reach the temperatures that petrobond can, and the finish won't be as nice -- but it's far cheaper heh.

There's a semi decent chance I might take ya up on the offer for a bit of help.  If anything - it'd be an excuse to get together over a cup of coffee heh.  Note that I'm doing my melting out of a detached garage at an apt complex - so snow and stuff incoming shall be fun :D.  Don't have a schedule planned yet.  Busy at work, holiday, etc.


hoppe's #9 is not the end all be all woman catching pheramone people make it out to be ... cause i smell of it 2 or 3 times a week but remain single  >:D

Offline unfy

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Re: Aluminum melting
« Reply #70 on: November 22, 2016, 03:23:28 PM »
The reason I'm curious about cast is I have some cast aluminum pole bases and aluminum poles (5" if memory serves) I was planning on scrapping but wondered if they can be melted down for a usefull purpose.

I'm currently in the "this has been fun and learning a lot!" (seems a lot of my projects work out that way....)

If you can think of anything you'd want cast, then maybe there'd be a use for it.  There are some rules for casting.  If we go the 'lost foam' route - you construct the object out of styrofoam or insulation foam, we pack it in a bucket of sand and pour the molten metal on it.

2 part casting with flasks (as m morton mentioned) - there are some rules as to what the shape the object is due to the fact that you're taking a pattern / object, cutting it in half, and packing sand around each half... then have to remove the halves.  Think in 3D concerning the sand and you can see how the rules come about.

Any kind of precision object (something you add to reloading press or a firearm) would need machine work afterwards.  shooter has tooling for that, but I do not.  I can grind, polish, drill holes, and tap some common sizes.  That's about it :(

hoppe's #9 is not the end all be all woman catching pheramone people make it out to be ... cause i smell of it 2 or 3 times a week but remain single  >:D

Offline m morton

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Re: Aluminum melting
« Reply #71 on: June 27, 2018, 12:11:46 PM »
for you all that melt aluminum this is cool



I will allow myself one personal observation. If you want to disarm yourself, that is your choice. The following quote is a favorite of mine and something to keep in mind when you make that choice.

“Sheep don’t tell wolves what’s for dinner.”

Offline shooter

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Re: Aluminum melting
« Reply #72 on: June 27, 2018, 03:07:21 PM »
 this must drive the animal rights wacos nuts.    but it looks neat. almost like a christmas tree. just put some lights on it !
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Offline GreyGeek

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Re: Aluminum melting
« Reply #73 on: June 29, 2018, 07:49:25 PM »
this must drive the animal rights wacos nuts.    but it looks neat. almost like a christmas tree. just put some lights on it !
It's a short drive!  Most of them took that trip years ago and never came back.