TECH: Make a Bellhousing out of an old Intake Manifold!!

Amazing thread, The HAMB puts yet another item on the "to do" list.

 

Wow!

 

i wanna forge something...but im think ill burn down the garage/house

 

looks like the stuff we made in high school about fifty years ago !! great job..be careful of wet sand it can explode......DRAK

 

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Yes.....if you clean off what you think is aluminum with a file, and dab on some plain old vinegar, and it reacts with the metal, it's probably magnesium. AL won't react with vinegar.

LoudPedal.....I'm sorry now that I hadn't been following this thread. I just burned the core out of my charcoal furnace on thursday. Have to pack up an insulated lid for it, but I did melt down a small amount of al while doing the curing burnout.
Are you on BYMC?

Congrats on the win.....well deserved.

Roger

 

Virgin ingots will always give cleaner pours than recycled metal with god knows what impurities .That said , I still have to flux the load . I use rock salt .Pouring during rainfall or with high humidity can introduce porosity .Seal the crucible with a lid or pour on dry days .The lost foam process ,has not been fully explained .Its called shell molding , the foam mold is coated with a liquid clay ceramic solution and dried , several times than the foam is removed by baking .The matal is then poured .Steel or iron crucibles will leach iron oxide into the melt .They can be coated with sodium silicate and cooked to seal , but proper crucibles are a good investment .The more things that cause problems are eliminated , the better the pour.

 

anyone ever use "blue ram" trying to buy some refractory sand/cement and getting sold plastic...who knows?

 

Bitchin, bitchin, bitchin!

 

still scratching my head a bit.....
Fullhouse296...can you go into some detail about the shell molding process???
the master(foam) is coated with the liquid clay solution...how thick is when done??
do you need to support the burn out mold before you cast..if so how??

 

I've used the ceramic shell process, and it is really nice, and has excellent detail, but last time I checked, it's also very expensive. This was about 20 years ago, so it may be cheaper and easier to use now.

It's a combination of fused silica and a proprietary slurry that must stay in a certain temperature range, and stirred up throughout the entire cycle. Most guys have a machine that mixes the slurry constantly in a temperature-controlled room. The only time it stops is so you can dip your mold.

It's first dipped in the slurry then rolled in the fused silica. Depending on how thick your cast part will be, you'll need around 6-12 coats on it with a few hours between coats. If you try to build it up too fast, it will probably crack. If it's dry on the surface, you're probably ready for the next coat.

When you go to burn out the mold, put it in a kiln first for a day or so and gradually build up the temperature until you burn out the mold so it's a clean mold. The only thing we used was styrofoam, wax, and some paper-not too much since it takes a long time to burn out paper-, with wax for the sprues and vents with a paper cup for the pour cup. To allow the slurry to stick to the mold, we coated everything with hairspray or shellac. Don't forget to allow for shrinkage if it's a precision part. Hope this helps.

 

I have thoroughly enjoyed your post! Building my own casting foundry has long been on my list of 'things to do'. You've just bumped it up in priority! Thank you so much for taking the time to post your experience and sharing you exuberance for the craft/skill/artistry of casting your own metal parts!

Dan Stevens
dba, Steelsmith

PS you can continue the lessons in casting anytime!

 

Hey guys I joined because of this thread, good stuff. Loudpedal- thank you for sharing, taking the time to show the eager not so experienced, how to think outside the box, and not meet our end in a box is much appreciated.
I do have a few questions,
-What are the limitations of this type of casting as far as structure is concerned? I see people making running models of motors and such on youtube, but is there a way to work with major structural or mechanical parts in full scale? Has anyone at home, cast brake calipers, spindles, pistons, con rods, etc?(and lived to tell the tale)
-Has anyone ever used a more user friendly form of lost wax casting? I remember seeing something about a nomadic people in India(?) that used a 6000 year old lost wax tech to make metal statues of deities for income as they traveled town to town.

-Loudpedal,
What are the basic details of you casting that bell housing? How many flasks?
What size is the crucible you had to use?
How in the world do you set something like that up to pour?

I just am having trouble mentally understanding the dynamics of pouring on this scale.
Do you have just one sprue?
How do you insure a full mold as it seems from an inexperienced logical perspective there would be a lot of cooling and temperature differences at this scale?

I have not experienced casting myself but am greatly looking forward to it. I appreciate any help that can be given as this is a most intriguing subject. Thank you in advance.

 

Nice work Kris, I have not read every post but skimmed thru this thread.
You obviously know your stuff, so I was wondering if you could do a bit more on cores for casting more comlplex stuff.
I am a beginner who has taken the 1st few steps and cast the Cadillac flathead stuff shown here on another thread some time back.

Core casting etc seems to be more a well kept secret and Id like to get a little more knowledge from the ground up and your way of telling it seems to be easy to understand.

Thanks, Russ.

 

I think most if not all of the stuff you list should be forged rather than cast. Moreover spindles I see more readily in steel than aluminium (there are home founders going into casting iron, but that's a whole different kettle of fish).

But I'm also interested in home-cast parts that are functional rather than decorative. At one end of the spectrum are things like blocks and heads. I can imagine stuff like V8s that never were, straight-eights, and H8 arrangements using four-cylinder heads. Or how about a twin-crank, double-decker Subaru flat-square-8? That might have four heads, of which the upper ones are upside-down: all it'd need is a block to hold it all together. And then, there are all kinds of possibilities in ioe (F-head) engines based on flatheads, especially if one were to cast a block with non-siamesed ports that can all serve as exhausts.

At the other end of the spectrum are, for instance, carb cores: 2½" SU, anyone? And blower cases, and all manner of drives and manifolding.

 

Beautiful head covers on the flatty---you're way out of my league.

 

Excellent Tech, one to save.

 

Dammit. I'm finally not in trouble with the old lady for building a smoker the size of a car and now I find this thread. She's going to think I'm determined to burn the place down.

 

Yeah, You and I are thinking different roads to the same end. I like the ideas on heads and blocks. There was even a video on youtube of someone casting a block to use f4 honda motorcycle heads in a v8, I would like to hear a 1.5-2.5L(ish) honda V8 just to say I did.
The real curiosity I have with you saying things like brake calipers need to be forged is why? It seems to me that it would be possible to cast almost anything that is forged if enough care and consideration are taken, the only reason I have to audacity to state this is because a couple months back, "Race Car Engineering" had an article about coatings and metallurgy, and in reference to forging and crank shafts they had said, (I loosely from memory recall) 'forging is meant to align the molecular grain structure of the metal for it to conform and align to the shape of an object.' they went on to say,'basically in a crank shaft this alignment is not of much importance as the alignment is interrupted drastically between when it is stamped and then machined.' It makes since if you see the shape of the forging before machining. They look like a bunch of round shapes molded into each other. The journals and counter weights have 1.5X-2X more mass than after machining. They said that the major strength difference came from the metallurgy, elevated attention to detail in higher cost forged products, and final coatings and heat treatments.

With that said, and the thought of what was posted by loadpedal (bell housing and such) if someone were to adapt a tig welding type atmosphere purge on their furnace, use a cover and tig cup style for the crucible, and purge their flask with gas also. With attention to buying actual fresh metal and being able to control the alloy by weight. Would not anything be possible? I know I am comparing steal to aluminum but shouldn't the same principals apply? I am just curious as to why I don't find more info on people making their own functional parts, when I cant seem to find any reason why not.
And as to the forged concept, 1700's samurai swards are credited as some of the first forged steal. and very high quality at that. It just seems to me that 21 century pace and greed leaves a lot of room for looking back 100+ years and researching crafts that have long been lost, that could yield a home made product by far superior to anything made now in our made in china sociaty.

 

Very well said! Something else I need to learn, cant stop thinking about it.

 

I am going to bump this thread for posterity.

Between the tech, the references and the links this is an absolute wealth of information.

But, to add a question, would the wheels and intakes and trans-cases be something one could cast engine parts, such as cylinder heads out of?

 

love to try it some time

 

this is an awesome thread,im glad someone dragged it out,my plan is to use a section of insulated chimney pipe,good to 2200 degrees.and i happen to have a drum full of coal a friend passed on to me.
the casting sand is easy,i need to cast some door handles and window cranks.
it sucks that i tossed an aluminum engine and trans this past summer.

 

Check out http://backyardmetalcasting.com/index.html, they have simple, inexpensive books showing all you need to get started, and lots of info on their website as well.

 

I'm glad this thread was resurrected. I've been wanting to give this a try for awhile. Hopefully, I won't set fire to something.

 

The mold "explodes" because of trapped steam due to the molten alumiunum hitting the misture in the mold.

If you drop molten al into snow, you'll get steam.

 

v8nova64 -
Here is a mixture that I used for several years until I sprung for some Petrobond sand mixture. The finer the sand the more you will like the casting's finish and ofcourse the detail of the casting, but I guess that isn't too hard to understand.

50 lbs. - Silica sand
9.375 lbs. - Low firing temp clay. It’s not the typical bentonite clay that every one says to use but it is what I had on hand from another project.
3.125 lbs.- Straight 30 weight motor oil
mix all together and the more you use it the better it seems to work and if it seems like the oil is getting burnt out just add some more to the mixture.

Not trying to jump this thread but here are some threads I did many years ago on here for casting tail lights. It has some step by steps in it you might find useful.

Smokey


http://jalopyjournal.com/forum/showthread.php?t=48504

http://jalopyjournal.com/forum/showthread.php?t=48868

http://jalopyjournal.com/forum/showthread.php?t=49040

 

v8nova64 -
Sorry I don't have a name for the clay but it was just a low fire white "powdered" clay. It would be listed in the powdered clays. The clay and oil coat the grains of sand and help to bond them together just like the clay and water would but without the steam or venting problems. So I would think that even a simple terra cotta clay would work fine and you can find that about anywhere . I am no purist so I just experiment around til I find something that works. I live in clay country and have my own pit on my property so the clay for me is not a problem. You could look at places like Continental Clay. com in MN or other clay supply houses The bad part about buying clay is if you have to ship it, shipping can be more than the cost of the clay. Hope this is of some help.

Smokey

 

Love this thread

 

bentonite clay is cheap kitty litter.

The "special kitty" brand at walmart is bentonite.

You will need to crush it finer though.

 

..and make sure you have dug a hole big enough for it when you find that it doesn't work that great.

All you can do is try it. If you read the first part of this thread all of this stuff is covered. Sould look like granulated sugar...

Look at the picture of the mix in the wheel barrow... About that much.