www.TK560.com Forum Index www.TK560.com
Vacuum Forming, Movie Prop, Sci-fi and GIjOE Forum
 
Log in to check your private messagesLog in to check your private messages

Log inLog in  RegisterRegister


Profile  Search  Memberlist  FAQ  Usergroups
Small aluminum/bronze furnace
Goto page 1, 2  Next
 
Post new topic   Reply to topic    www.TK560.com Forum Index -> Off Topic
View previous topic :: View next topic  
Author Message
Fredo
Expert


Joined: 21 Mar 2007
Posts: 247
Location: Kingdom of Nye Area 51

PostPosted: Mon Oct 14, 2013 2:08 pm    Post subject: Small aluminum/bronze furnace Reply with quote

I built this small furnace for aluminum/bronze, but mostly alum.. The last pic is of a few ideas of what to cast... Mostly what I've been working on are skull themed ashtrays in alum.. I'll put up some pics of of the molds.







Can't figure out why the pics stack like they do? The white plastic mold I bought on line.. I cast a water putty mold from it.. I removed the divider in the top part of that mold for the RIP letters I cut from 2 mm aluminum sheet. I pulled another mold from the plastic mold I made with my 12"x12" vf. The two white molds are an attempt to reduce the amount of metal needed.. One I reduced the volume of the ashtray and the other I hollowed out the back... I think I've reduced the weight over the original casting by about 40%.
I can't unlink these god damned pictures from their albums and their all mixed up..... Don't click on the pics unless you want to go to photofucket....




_________________
If someone has a gun and is trying to kill you,
it would be reasonable to shoot back with your own gun...The Dalai Lama..Seattle 2001


Last edited by Fredo on Mon Oct 14, 2013 8:40 pm; edited 1 time in total
Back to top
View user's profile Send private message
IMMark
Expert


Joined: 18 Nov 2010
Posts: 189
Location: Columbus, Ohio

PostPosted: Mon Oct 14, 2013 5:51 pm    Post subject: Reply with quote

Thanks for sharing Fredo...always interesting to see what people are up to.
What is the heat source for your furnace?
Mark
Back to top
View user's profile Send private message MSN Messenger
Fredo
Expert


Joined: 21 Mar 2007
Posts: 247
Location: Kingdom of Nye Area 51

PostPosted: Mon Oct 14, 2013 8:34 pm    Post subject: Reply with quote

This a test fire on my shop bench, I'd never try to melt metal in the shop. Here's also a few pics of the burners I made from pipe and fittings. The valve at the burner is a 1/4" water valve and the gas orifice is a .035 MIG tip. This 1/2" propane burner is running at 8# pressure.. Here's some pics of burners I made.


_________________
If someone has a gun and is trying to kill you,
it would be reasonable to shoot back with your own gun...The Dalai Lama..Seattle 2001
Back to top
View user's profile Send private message
IMMark
Expert


Joined: 18 Nov 2010
Posts: 189
Location: Columbus, Ohio

PostPosted: Tue Oct 15, 2013 8:42 am    Post subject: Reply with quote

Sorry, I don't know much (or anything) about such projects....is the reason not to use in the shop fumes? It seems like I have seen many small forges inside of shops running?
Also, is the black plastic ABS?
Mark
Back to top
View user's profile Send private message MSN Messenger
Fredo
Expert


Joined: 21 Mar 2007
Posts: 247
Location: Kingdom of Nye Area 51

PostPosted: Tue Oct 15, 2013 12:45 pm    Post subject: Reply with quote

Propane forges still need some venting.. In a closed area propane will use the oxygen and replace it with carbon dioxide.. The big plus for propane is that it doesn't make carbon monoxide..
Although not fatal, zinc fumes will make you really sick and melting aluminum requires fluxes and degassing agents and can produce chlorine gas.. Inert gas can be used to degas the aluminum instead, if you have it, or can afford a tank.. Casting metal is not an expensive hobby, on the low end..

The black plastic is abs.. My little 12x12" vf is really handy for making plastic molds for water putty... I alter the water putty molds and make a new plastic mold.. Don't anyone get their knickers in a knot, I just can't feel bad about copying cheap imported Chinese shit..
_________________
If someone has a gun and is trying to kill you,
it would be reasonable to shoot back with your own gun...The Dalai Lama..Seattle 2001
Back to top
View user's profile Send private message
IMMark
Expert


Joined: 18 Nov 2010
Posts: 189
Location: Columbus, Ohio

PostPosted: Thu Oct 17, 2013 9:17 am    Post subject: Reply with quote

Nice job,...if you can, please update with pics and progress. Would love to see finished castings!
Also, darn you...now I may have yet another hobby : )
Mark
Back to top
View user's profile Send private message MSN Messenger
Fredo
Expert


Joined: 21 Mar 2007
Posts: 247
Location: Kingdom of Nye Area 51

PostPosted: Fri Oct 18, 2013 1:46 pm    Post subject: Reply with quote

I've done investment casting using a Kerr broken arm, spring driven, casting machine. I've used both the long and short arms.. The long arm will take up to a 4"x6" flask... I always used the short arm because with its base it fits in a wash tub, that makes a good splash shield.. With the Kerr, metal is melted in a crucible mounted on the arm, it slides up to the flask when it's in position... The metal in the crucible moves to the flask in a second when it spins.
Melting metal in a furnace and pouring into a sand mold by hand is new to me.. But, what the hell, a man can't have to many hobbies.. Stop taking on new hobbies and you stop learning... When we stop being the makers of things, we become the cattle called consumers....
This site is so slow now days I thought I'd start a thread and keep track of my new venture here...
Let me link you to Myfordboy, he has a series on sand casting, most are under 15 min. http://myfordboy.blogspot.com/ ..
I'll keep you up to date and answer any questions you have.. You're sure to have a few after watching his videos.. Be sure to check out his You Tube channel
_________________
If someone has a gun and is trying to kill you,
it would be reasonable to shoot back with your own gun...The Dalai Lama..Seattle 2001
Back to top
View user's profile Send private message
IMMark
Expert


Joined: 18 Nov 2010
Posts: 189
Location: Columbus, Ohio

PostPosted: Sat Oct 19, 2013 12:39 pm    Post subject: Reply with quote

I will have to look into some casting...seems fun and useful!
Thanks for the Myfordboy link...I started watching some video's, great stuff...I am sure there will be questions down the road.
Along the same lines of not having too many hobbies...this is what has been taking up my time and $;
http://www.mechmate.com/forums/index.php

Don't know if you have ever heard of it or have any interest....let me know if you do.
And yes, please keep the posts/updates coming...knowledge is power!!
Mark
Back to top
View user's profile Send private message MSN Messenger
Fredo
Expert


Joined: 21 Mar 2007
Posts: 247
Location: Kingdom of Nye Area 51

PostPosted: Wed Oct 23, 2013 8:52 pm    Post subject: Reply with quote

Did my first melt in the furnace.. I used zinc because I thought I had enough metal to do the job.. Wrong.. The zinc I used was heavy chrome plated zinc..... I used zinc for my first melt because of its lower melting temp. http://www.a-m.de/englisch/lexikon/giesstemperatur.htm I lost more metal by drag out than I anticipated when skimming the plating off the top of the melt. That left me short..... I plan on using only clean ingots made from metal thats been melted and had the dross removed..... Dross is whatever winds up on top of the melt.... Second time around the metal makes very little dross. One skimming and your ready to pour...My next melt will be aluminun... Hopefully this sunday...
You can see where the front tooth is missing in the pattern..The missing tooth will be cast in brass and set with a 4.5mm CZ. The pupils of the eyes will be set with 8mm black onyx cabichons.... If I buy 50 of each stone, the cost of the 3 stones is about $1.00 total. Really, no bs.... The CZ will be cast in place in the tooth by centrifugal spin casting.....Setting the cabs 5-10 minutes.. Maybe 20 minutes total, including setting the tooth in place.. I'll set it just like it was a stone, no solder..
For the tooth, I'll make a wax that fits the pattern and cast that in brass. Then make a rubber mold of the brass tooth. Wax will be injected into that mold, the stone then set in that wax for casting with the CZ in place...The CZ will take the heat with very slow cooling of the investment mold... The pic of the burner is to show how I changed it from 1/2" burner to 3/8" burner using a 1/2" to 3/8" bushing and a 3/8" burner tube.... The 1/2 inch would have been to hot. The 3/8 burner gave me a slower melt without the risk of over heating and making zinc fumes...
I'll edit in new pics in the morning....done




I built the 9.5"x9" flask out of scrap wood.. Wooden flasks work just as well as the store bought metal ones. The main requirements being that they must mate with no gaps, and have guides on the sides to realigned exactly the same each time they're put together..
The red sand is mulled 140 mesh petro-bond I bought on line. The stuffs not cheap, I paid $100 for 70lbs shipped... This eliminates me trying to blame any casting problems on bad sand.... Besides making greensand is a hit and miss operation until you get it right... You need use a muller to get right.. I just don't have the time for that..
_________________
If someone has a gun and is trying to kill you,
it would be reasonable to shoot back with your own gun...The Dalai Lama..Seattle 2001
Back to top
View user's profile Send private message
Fredo
Expert


Joined: 21 Mar 2007
Posts: 247
Location: Kingdom of Nye Area 51

PostPosted: Sat Oct 26, 2013 1:20 pm    Post subject: Reply with quote

I may be making just ingots tomorrow.. In between castings I thought I'd pull a wax impression of the ashtray for a later investment casting.. It was to be a negative impression for casting an aluminum EPS foam mold.. The pictures are of a wax I pulled from an unpainted mold for a test to see if it would work.. It was done on glass and worked fine... This time when I did it I made one little mistake... I forgot the mold release... Scratch a weeks work on that pattern.. I hadn't made a finished VF mold of of the one with eyes......
A little explanation of what I was trying to do... Expanded polystyrene is what's used for making duck decoys.. My reason for wanting to make foam ashtrays is so I can do lost foam casting... I've come realize, in a flash, pounding sand is not that good for my arthritis.. With a foam mold, the mold is coated with drywall mud, dried, then buryed in loose dry sand. Instead of pouring directly on the foam, most people dissolve the foam with acetone to reduce the gas that's created. The resulting hollow shell is fragile, but can be handled, with proper care... Some sprinkle sand on the first coat and re coat with more drywall mud for a little extra strength... Youtube has a lot of videos of sand and lost foam castings...





Mark, how far are you into your mechmate build?? If I had one I'd build precut plywood boat kits. After the wood is cut, most DIY plywood boats are a weeks work, or less, to give you a 90% finished hull.. Just one of the things I've thought about...
_________________
If someone has a gun and is trying to kill you,
it would be reasonable to shoot back with your own gun...The Dalai Lama..Seattle 2001
Back to top
View user's profile Send private message
Fredo
Expert


Joined: 21 Mar 2007
Posts: 247
Location: Kingdom of Nye Area 51

PostPosted: Wed Oct 30, 2013 3:50 pm    Post subject: Reply with quote

Sunday...I made a few pounds of aluminum ingots for another try at the ashtray... This is a fairly small furnace, 4 lbs of aluminum is about all it'll melt at one time... enough to pour two ashtrays.. The bore is only six inches, and the crucible, a disposable propane cylinder, is about as large as will fit.. I'm already thinking there may be a bigger furnace in my future...
Worked on a new pattern. It'll take a few days to dry enough to use.. These water putty molds are easy to work with but they're only for temporary use....
Rammed up the mold for the next casting last night.. It was a nice morning, the winds are gone. Got up at sunrise to cast while the furnace was still in the shade... Last time it was in full sun and a little hard to see inside.. I'm not unhappy with the casting.. There would have been less porosity if I had used a better aluminum alloy... The best alloys are old aluminum castings, wheels, lawn mower engines, things that call for a better quality of aluninum... cans are about the worst choice... they're painted and so thin they oxidize and produce a load of dross.
A few pics of the casting. The pics are all mixed up in the album so you need to click on each one and not try to scroll on photofucket..


_________________
If someone has a gun and is trying to kill you,
it would be reasonable to shoot back with your own gun...The Dalai Lama..Seattle 2001
Back to top
View user's profile Send private message
Fredo
Expert


Joined: 21 Mar 2007
Posts: 247
Location: Kingdom of Nye Area 51

PostPosted: Fri Nov 01, 2013 2:02 pm    Post subject: Reply with quote

Here's the ashtray finished, still needing the stones... With this casting I'll be setting the CZ in the aluminum tooth.. Next one I'll give the brass tooth a shot.. Try to give it a gold tooth look... Ordered the stones for the eyes and tooth... 20-10mm onyx- $7.60, 50-4.5mm CZ - $16.60 + $9.10 shipping... After this first successful ashtray casting, it's back to trying for my negative wax mold again.....

_________________
If someone has a gun and is trying to kill you,
it would be reasonable to shoot back with your own gun...The Dalai Lama..Seattle 2001
Back to top
View user's profile Send private message
Fredo
Expert


Joined: 21 Mar 2007
Posts: 247
Location: Kingdom of Nye Area 51

PostPosted: Fri Nov 08, 2013 1:39 pm    Post subject: Reply with quote

Here's a couple pics with the stones... I have some red carnelian cabs back ordered that I'll use in the next one...
The one at an angle was before clean up.. The CZ really seems dead set in the aluminum.. It'll need to be set in yellow brass to jump out at you.



_________________
If someone has a gun and is trying to kill you,
it would be reasonable to shoot back with your own gun...The Dalai Lama..Seattle 2001
Back to top
View user's profile Send private message
IMMark
Expert


Joined: 18 Nov 2010
Posts: 189
Location: Columbus, Ohio

PostPosted: Fri Jan 10, 2014 5:33 pm    Post subject: Reply with quote

Wow, I have been gone awhile...time flies!
Those look great. I have started my furnace build too. Just a small one, I have the tank cut and floor poured. Have most of the parts for the burner too. I will post some pics when I get back to it.
Thanks
Mark
Back to top
View user's profile Send private message MSN Messenger
jdougn
Guru


Joined: 18 Mar 2009
Posts: 714
Location: Louisville KY area

PostPosted: Thu Feb 13, 2014 7:43 pm    Post subject: Reply with quote

Yeah, this is definitely an interesting thread! I've done a little metal casting in the past, just enough to appreciate all the hard work!
_________________
DougN - Just in case you're wondering, I got my "rating" legitimately... by posting aimless drivel, useless advice, and pointless questions.
Back to top
View user's profile Send private message Visit poster's website
Display posts from previous:   
Post new topic   Reply to topic    www.TK560.com Forum Index -> Off Topic All times are GMT - 6 Hours
Goto page 1, 2  Next
Page 1 of 2

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum

phpBB "skin" by DewChugr


Powered by phpBB © 2001, 2005 phpBB Group