Because of the success in casting the wire wheel adapters I am going to try something I have wanted to try for years. I want to cast my own slant six racing pistons. I already had started several years ago to make a permanent steel mold. I was afraid I had thrown it out but I searched today and found all of it. I was working on it a bit this afternoon. I have to make sure it is solid. Can be forced apart if need be without damage and that any inner cores have enough taper to release well. I made one piston just for fun several years ago when I got my frnace finally working. Now i have it cooking the way I want with this last project. I scored a set of 454 cast pistons to melt down first into ingots so I can use them in my melting pot . It holds about 800 grams safely. I wont need that much for each piston. Here is one I poured just for fun a few years back. Is it a dumb idea? Probably . But it will be interesting. I work on things a bit at a time so i dont get in a rush and ruin it. The tunnel ram manifold is coming along nicely with a nit of progress each day that i am in the shop working. The wheel adapters need wheels so I have to wait for my trip to the bike salvage guy . The race car is loaded ready to go to the track in the morning. This is our last race for the year so after draining the antifreeze and storing it ,its project time. Dont know how this will turn out but i gotta try. (what if it works out?!!!!) Don
Well.....good for you ! Sounds like nothing scares you, so just do it. Having worked for a company that has made pistons for over 75 years, there is a lot more to it than meets the eye. Have fun!
Yes i believe you. I have to start somewhere though. It may be a waste of time but I will learn something from it. I hope to pour the first in about a week. i guess truth be known it is on my bucket list. Sort of ike I read how the worlds oldest emmigrant at 103 was wanting to immigraet to New Zealand from England. He was asked by a news reporter why he would immigrate at 103. His answer I love. "because i dont want to be 105 wishing I had done it when I had the chance. " I dont want to turn 61 without at least trying this. Don
Please do it ! Just pay close attention to ring groove tilt, depth, the taper from top-to-bottom, pin bore and oiling, and the proper location and sizing of the oil drains inside of the oil ring groove. Basicly, reverse engineer an exsisting part and you'll be fine.
I thought about the movie worlds fastest indian. (i think it's called) when i read your post. good luck with the castings.
I guess I could understand this undertaking if there were no commercial pistons available that met your needs. To be truthful, it just seems to be a ton of work requiring research, exact machining skills and the high possibility of failure.
We used to refurb some of the single cavity molds that a company in our area used to gravity cast pistons.I was able to go down to their plant and watch them pour and cast the parts.It was pretty primative but looked pretty easy to do.There wasnt to much to the molds just a large gate area with some large overflows that showed when the parts were filled.Broke em apart after they cooled and bingo they had one piston ready to machine and use.I think the guy there said he made about 4 per hour.Looked like pretty hot dirty work.Glad i stuck to building the molds.
Hey Don, As a Kiwi from a nation of "do it yourselfers" I totally admire what you're doing. Plenty of people here in NZ have sand cast pistons before To get a high silicone "hypereutetic" alloy, just use some old slugs for your feedstock here's a bit of reading for you http://en.wikipedia.org/wiki/Hypereutectic_piston Try it on a "Briggs" engine first [ then get it running on nitro while you're at it , to mow the lawns ] Have you ever considered a "Billet Piston" [ don't say "arrrgh billet" ] the underside could easily be milled out with a "slot drill" I know from reading your previous posts that you have the skills to do this
Excellent engineering exercise. When fabricating something like this I do listen to the opinions, advice, of others, but part of the learning process is sorting things out yourself. Listen to it all, good and so-so, put it all in a pot, stir it up, and see what makes sense to you. And, mistakes, failures, are all part of the scene. PLEASE keep us updated with words and photos. And, I wish you all great.....learning...success.
So to put it simply.......EVERYTHING!! Good luck, casting is something that fascinates me too. Unfortunately the biggest I have gotten to is 1/25 scale! Please keep us updated! Doc.
Nothing wrong with cast pistons either, a lot of offy's ran cast because it built more power. I even read an artical that they mentioned experimenting with MAGNESIUM pistons!!!
has anyone cast a piston by spin casting, i think i'll ad this to my bucket list, last week i picked up a kiln for free off of craigslist, stands about 3ft tall, about 1-1/2 ft in dia, i want to pull the electric coils out and ad a propane burner.
Dolmetsch, I know you're gonna' keep hearing people ask you "why". Hell, I even thought of asking. But, then I thought about the fact that if a guy did develop the ability to 'roll his own', he could try out different configurations a lot quicker/cheaper than placing an order with, say, Diamond. And waiting. Have you checked out the forum at speedtalk.com? There are some pretty talented guys over there who will probably ask "why?", but there is at least one or two piston mfgr's on the board. You might come up with some insight over there. Best o' luck! -Bill
wow... absolutely awesome. I have quite a bit of casting knowledge... formulas and what not. never casted a piston myself. when I did my first bottle opener quite some time ago, i forgot about shrink and its just a paperweight now, look up shrink formulas and make sure to make the sprue and riser good and large to prevent inclusions in the castings. abso-freaking-lutely go for it and please keep the updates coming!!! cant wait to hear! break a leg!
The machining I am used to . This pic was almost 20 years ago . I have made pistons for years from other cores. Usually TRWs. TRW used to supply minimum thicknes specs for both cast and forged. I built in the mid 90s a 460 cu inch engine from a 400 Dodge. Hand made everything but the crank (and I have hand welded and stroked a crank as well. ) That engine appeared In Chrysler Power Mag about 1997 , July maybe . I entitled the article All The Wrong Stuff but the publisher Editor Roland changed it to Econo $1500 Big Block because that is what it cost us. I later built a 426 from a 400 for the same guy using a mildly stroked 383 steel crank and .030" 440 TRW forged replacement castings. Since we used Eagle H beams I even had to machine the lock ring grooves. That was several years ago and my pal still runs it in his RED now. Still going strong. I have done 250 chevys welding up the valve reliefs on 307 pistons to make real flattops. I know you shouldn't weld pistons but we have never had one of these ever fail. Then I built an experimental stroker . 482 cubes from a 440. Welded crank 3.96 stroke. I used Ford 429 pistons and welded up the valve relief then remachined them. I had trouble with this one as al pistons were not identical underneath.. Probably made in a different die as they were forged. Three pistons blew a tiny hole through on fire up. I could tell from the breather something wasnt right. I pulled it own and fixed the bad ones then decided to fix them all for safety. That has sat under my bench for years and I finally pulled it out and finished all the work. I sold the block assembly as an experimental engine for $2500 . The crank (hard chromed welded stroker ) is probabaly worth that. So I am used to machining pistons . Casting them is another deal but I am listening and watching for info. I may pour a couple of wax ones first to see if my mold needs any mods. I am excitied though about trying it. My nephew would say , Unc Don. Why do we build stuff when we could buy it?" To which i would reply, "Sorry for your loss". Thanks for the encouragement and the tips. I have a plan for these. We shall see if it works out. Don
Don, could you post some more info about your mold? I've been thinking about casting some pistons (or even making them from billet) for the Buick s8 I've been working on for a while (background project)
A very good answer. Probably every serious project in my life, cars, bikes, building, electrics etc, that I've had to do research on, has led to at least one person telling me I should 'get a pro to do it' as it would be safer/easier/cheaper/better. Sometimes we simply want to experiment and have a little fun, test ourselves, see what our limits are. Have a read of the book 'One Good Run' which is basically the true story of Burt Munro and the Worlds Fastest Indian. You'll see some incredible stuff about building performance parts in a tiny workshop, with extremely primitive equipment. Hand cutting/filing con rods, cams, rockers, valves etc. It really is an interesting and motivating book.
http://www.lindsaybks.com/bks8/mpiston/index.html Here ya go.....somebody already has a book on it...Shawn
I agree with all those who think this is a dumb idea. All the really good ones are. Wish you lived artound here. I would love to see and maybe help on this one.
I will post pics of my mold so far but we have an actual piston mold builder on this thread. Perhaps he will give us a rundown on how hemade them. Don
The molds we built were for a major manufacturer.I dont think i could post much for information as there could be some non disclosure issues.
I think it will work. I took a casting class once and a bloke made some tractor pistons from a steel mold that was basically made from steel pipe and they came out well. He melted down old pistons so the alloy was right. When it come time to machine them, you can emulate the cam turned feature by putting bolt through the wristpin boss with a nut on the other side. Tightened it to get the out of round you want. Machined it. You get the rest. Good luck, but you won't need it! Steve
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