It could be cheaper is you built a gazzilion of them.So other than being different, it sounds like it will be heavier, weaker, perhaps more expensive. As compared to good old welded tubes what are the potential advantages?
There are actual standards for the aerospace industry that specify what manufacturing processes can be used for different components on airplanes. Wouldn't you know casting has the highest probability of failure for any metal forming process, next time you board an airplane look for something that is rough cast, I'm betting you won't find any. The last plane I was on and paid any attention to, had machined supports for the arm rest on the chairs in coach.
strong enough meaning much heavier. 747s are built like tanks compared to what they're doing now, where purchases are made based on efficiency.Many of the parts we made where for 737s and 747s and where designed before 4 and 5 axis CNC machining became common. Back then, casting was the cheapest way to achieve the parts shape and it was "strong enough"
production dirt bikes are being made for cheaper production costs, not because of lack of know-how. I'm not sure if the race frames are different (i know most of the components are), but the weight/performance penalty isnt as big as it is for bikes, so less push for expensive refinements.there is alot to read. got through 3/4 the first page.
what i'm getting from all this is that casting isn't as strong as forging. and dirt bikes use casting.
does this mean that the motorcycle industry is going to be taking from the bicycle frame industry? making motorcycle frames using forgeing techniques?
Well, it's not quite as big a deal to save a few ounces here and there on a motorcycle, since the power source is bigger, so a thicker cast piece will suffice most of the time to obtain the necessary strength. It might be different for the uber-race bikes for the big budget teams, but for the majority of bikes, you've got a big engine so a less refined but heavier piece for the same strength will work.does this mean that the motorcycle industry is going to be taking from the bicycle frame industry? making motorcycle frames using forgeing techniques?
You are exactly right on why MX bikes use castings. With CNC machining of billet, a bunch of material is tossed in the scrap bin. Not cheap especially when you add in the $100/hr+ cost of running the mill. Forging tools can be $500k+.production dirt bikes are being made for cheaper production costs, not because of lack of know-how. I'm not sure if the race frames are different (i know most of the components are), but the weight/performance penalty isnt as big as it is for bikes, so less push for expensive refinements.
Neither, Solar Turbines.GE or Pratt?
Definitely. You can make some pretty amazing parts with the investment casting process. When I was working ofr the govt. we built some 6061 investment cast parts with hollow sections and 1.5mm wall thicknesses. Really pushing the limits of the process but the parts were amazing. That bike looks like a pattern mold to me though, at least based on how I would go about building tooling, but every designer thinks a little differently, so who knows. Makes me want to cast some random stuff! (like a new wood stove)The cast bike looks cool. I'll bet you could make it work with investment casting.
What the hell does that mean? I bet thats some weird Dave talk for nuclear missile made of aluminum foil and cast cheetos or something.dw said:Makes me want to cast some random stuff! (like a new wood stove)
No seriously I was checking out this awesome old wood potbelly stove at my frineds house on Wednesday. Somebody put a lot of thought into making the thing, it was awesome. All cast iron and brass. It made me want to build one of my own.What the hell does that mean? I bet thats some weird Dave talk for nuclear missile made of aluminum foil and cast cheetos or something.
Freak.
hahaha, what's wrong the old Ben Franklin get a hot spot? oh, how i don't miss needing the comfort of piping hot cast iron.Makes me want to cast some random stuff! (like a new wood stove)
Ooooohh! And if you managed to destroy it, you could light it on fire!DW, Speaking of casting or forging, what do you think of a Magnesium back plate or something like that to bring the weight down on the e-13 chain guides even more? i am not an engineer but who can forge or cast Magnesium? It would be cool if you could do it for a back plate/boomerang maybe???
You are such a nerd. I can imagine you crawling around oogling your friends stove while his wife is wondering if she should call the cops.No seriously I was checking out this awesome old wood potbelly stove at my frineds house on Wednesday. Somebody put a lot of thought into making the thing, it was awesome. All cast iron and brass. It made me want to build one of my own.
if you chage the geometry you have to almost completely re make the bike in the inventor CAD or simmular enjineering program and that can take a long time. my sense is that they figure out the geometry before designing it in CAD. that way they can fit the frame to the geometry that they wantI hope they got the geometry naile before they made the mold, because that mold must cost a sh*t ton.
hells no, CAD (especially 3D top down feature based modelling like Solidworks et al) makes the design process faster and easier (thats why we use it). Making a change like headtube angle takes about 5 seconds.if you chage the geometry you have to almost completely re make the bike in the inventor CAD or simmular enjineering program and that can take a long time. my sense is that they figure out the geometry before designing it in CAD. that way they can fit the frame to the geometry that they want
well shot-peening would be a very good idea here; it would give it that lookDunno if it's sand blasting - maybe, but could also be the normal finish if it was green-sand cast for a proto.