Intake Manifold Casting
04-22-16, 08:03 PM
#76
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Yeah, in basic layout that was the inspiration - I have an old 12A Lake Cities manifold kicking around. I never liked the way it transitioned to the keg though, and you can see how with the spacing of the snowmobile TBs how the outer ports get straighter shots than the LC one.
lol!
01-23-17, 01:27 PM
#77
spoon!
Thread Starter
Well what the heck, bumping this up because I've been doing casting things, even if not back to intake manifolds yet.
The trusty foundry in action...
Christmas present after pouring, breaking out and installing on its new home (Miata)
It was a good idea to give myself a project with a deadline to get my butt back in gear.
The trusty foundry in action...
Christmas present after pouring, breaking out and installing on its new home (Miata)
It was a good idea to give myself a project with a deadline to get my butt back in gear.
01-24-17, 09:46 AM
#79
Red Pill Dealer
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Awesome! Lost wax plaster investment molding? What are you using for melt?
01-24-17, 10:17 AM
#80
spoon!
Thread Starter
That was lost PLA investment casting done in a mix of plaster and sand (1:1:1 plaster, playground sand and water by weight) poured into an empty paint can for a flask. I need to make reusable flasks at some point but no big deal so far. Burn out was done in an old electric oven - initial heating was done for about 8 hours at 250ish F to bake a lot of the moisture out, another 4 hours at 400ish, and another 4 hours ramped up to 550+ (oven's "bake" temperature dial only goes to 550, but having the mode dial on "bake" and the temperature on "broil" makes the heating element go on after it had stabilized at 550) Then let it cool down, blow it out with compressed air, and heat it up to 500ish for a couple hours for the pour.
Not very scientific, but after having one attempt a year or so ago that resulted in a lot of steam bubbling out at the same time I was trying to pour aluminum in, I felt like being conservative, and this schedule worked. An extra day or two of burn-out was a lot preferable to the extra days to print more patterns and invest them when I had a deadline.
Big improvement over previous attempts was trying to do reasonable runner design - big sprue (I may be using the wrong words, problem with being self taught) with a tapered funnel was in the middle of two of those skulls, then fed those from about where the shifter threads in, and vented out vents on the top of the skull.
Not very scientific, but after having one attempt a year or so ago that resulted in a lot of steam bubbling out at the same time I was trying to pour aluminum in, I felt like being conservative, and this schedule worked. An extra day or two of burn-out was a lot preferable to the extra days to print more patterns and invest them when I had a deadline.
Big improvement over previous attempts was trying to do reasonable runner design - big sprue (I may be using the wrong words, problem with being self taught) with a tapered funnel was in the middle of two of those skulls, then fed those from about where the shifter threads in, and vented out vents on the top of the skull.
01-24-17, 11:22 AM
#81
Red Pill Dealer
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You just melting cans? It seems your plan was really good. I've been looking in to this lately and have practical experience from work. I have this idea of using a part in the plaster mold and drafting the parts accordingly to get more than one use but I have no experience in the plaster degradation (unfired plaster) after a use. I need to search this more.
I use to do some commercial permanent mold tooling work. They are made from steel but are not die casting. They usually have six sides like all cubes but sometimes only two or three, gravity fed from the bottom of the mold, venting (they used metal screen, that's those funny bumpy pattern in rows yet a circle on some stuff), and have locating pockets for premade sand cores.
They would heat those up to 750 degrees.
I use to do some commercial permanent mold tooling work. They are made from steel but are not die casting. They usually have six sides like all cubes but sometimes only two or three, gravity fed from the bottom of the mold, venting (they used metal screen, that's those funny bumpy pattern in rows yet a circle on some stuff), and have locating pockets for premade sand cores.
They would heat those up to 750 degrees.
01-24-17, 11:59 AM
#82
spoon!
Thread Starter
Heh heh... no, that skull was made from 100% recycled 1st gen RX-7 factory alloy wheels. Like everyone who raced 1st gens for a while, my dad and I ended up with a bunch of parts cars (literally about a dozen) and about twice as many wheels as cars that they were mounted on, so I just bandsawed a couple of the worst ones into chunks that will fit into my crucible and skimmed off the dross. May go and just buy ingots somewhere in the future though.
The plaster is hard as heck after it's baked and all. With the right part geometry you might be able to use it more than once, but obviously not with something shaped like that skull.
I'm thinking for the future to use the printed positive to make a mold to make wax copies - found a bunch of people who want their own fury road inspired skull shifter for example - but not really sure if my best bet would be printing a master, cleaning it up and making a silicone mold, or printing a female mold and being done with it. Things to experiment with, I guess.
I'm with a small engine company nowadays, in the R&D lab but the designers are inhouse. Interesting to see the back and forth between us and the foundry over die cast tooling.
The plaster is hard as heck after it's baked and all. With the right part geometry you might be able to use it more than once, but obviously not with something shaped like that skull.
I'm thinking for the future to use the printed positive to make a mold to make wax copies - found a bunch of people who want their own fury road inspired skull shifter for example - but not really sure if my best bet would be printing a master, cleaning it up and making a silicone mold, or printing a female mold and being done with it. Things to experiment with, I guess.
I'm with a small engine company nowadays, in the R&D lab but the designers are inhouse. Interesting to see the back and forth between us and the foundry over die cast tooling.
01-25-17, 02:13 PM
#83
Red Pill Dealer
iTrader: (10)
Well, that's where my livelihood is, diecasting. I've worked in many other parts of the tooling trade (primarily molding) but they are doing some cool stuff that really offers nothing to your pursuit in this thread.
That doesn't mean I don't like what your doing and am not interested. This stuff is totally doable, as you've proven. Best of luck man!
That doesn't mean I don't like what your doing and am not interested. This stuff is totally doable, as you've proven. Best of luck man!
11-30-17, 08:19 AM
#85
spoon!
Thread Starter
Oh boy... well.
Basically there's two problems with continuing as I was. 1, I need more foundry experience, 2, what do I do with the intake manifold once it's done?
1, after a busy year where most of my car-time went to roadracing an NC MX-5, I'm getting back to casting more skulls and some other stuff. Mostly decorative to get my foundry technique down. That intake manifold had a lot of print time and I don't feel like doing it next if I'm not confident in what I'm doing.
2, I bought an engine dyno from the Skip Barber bankruptcy auction. I figure what's the point of just building things if I can't test them too?
Basically there's two problems with continuing as I was. 1, I need more foundry experience, 2, what do I do with the intake manifold once it's done?
1, after a busy year where most of my car-time went to roadracing an NC MX-5, I'm getting back to casting more skulls and some other stuff. Mostly decorative to get my foundry technique down. That intake manifold had a lot of print time and I don't feel like doing it next if I'm not confident in what I'm doing.
2, I bought an engine dyno from the Skip Barber bankruptcy auction. I figure what's the point of just building things if I can't test them too?
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