i'd suggest fabricating ,welding , machining the guitar .
casting, outside of a specialiized industrial operation , will
be difficult ,at best . hydrogen will ruin the piece ,cause
bubbles and trash , unless the temp is just right , you flux it
right ,you'll get oxidation in the pour. buying a known casting alloy would help tremendously - scrap has to be melted and
purified . not to mention ...that's a big pour ! you'll need a
two-gallon crucible to pour that beast and purge the air
out + fill the sprue. if you don't......
the mostly pure 1xxx aluminum used for cans doesn't machine
well , doesn't hold screw threads , isn't what i'd want to use
to make anything tangible from. it sucks .too soft ,gummy .
7075 -t651 temper aluminum is stronger than 1020 mild
steel , and actually harder (RB-87 vs. RB-75) , but that
doesn't make it tougher or more wear resistant. besides,
you aren't going to cast this stuff... also ...can't really weld
to the stuff ..when they make structural airplane parts w/ it
it gets riveted/bolted in place. it's one of the more expensive commercial alloys .
6061-t6 temper is not as strong , not as hard , but can be easily welded . it could be feasible to fab a guitar from bar and
plate extrusions , TIG weld the assembly . once you machined
the fillet welds , the joints would be invisible anyway . once
you wore down the frets , you could get them built up and
mill them back to size . it's among the less expensive of the extrusions available.
i have heard of hardfacing AL
w/ a AL/CU/NI/FE plasma process . never seen it done ,though.
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about "billet" aluminum..........
Billet is an intermediate step in the manufacturing process .
AFAIK, NOBODY machines from billet . a billet is poured and
cast into an 6" to 12" round log , 20,30,40 feet long ....
(at this point the alloy has no temper from working and/or
heat treating )....
it's typically run through extrusion dies/rolls to make whatever shape it will end up as ...bar,round,plate etc...
"billet" is a bullsheit buzzword -created by bikers,truckers,grease
monkeys - to play up the fact that something was actually
machined , instead of stamped or cast .
why "billet" and not "ingot" i think ingot sounds better
