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ok so im getting into mechanical engineering and my dad is director of engineering at his work which my uncle owns. i asked my dad how hard it would be to make rims for my civic and he said it wouldnt be that hard as long as we can draw the models on the computer and the machines will do the rest.
but one question what type of metal is used for rims?
i know S-steel would probably be real heavy.
i think a certain type of alum would probably be the way to go.
anyone have any tech specs on what type of metal is good for rims.
btw im getting inspiration from the 5zigens for my rims.
thanks
-dan

 
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Ideally, you would like a forged billet of 6061 T6 Aluminum. If not, a cast billet would be acceptable. If I were you, I would find the type of rim that you would like to imitate and use a CMM to get the profile of the bead. Most wheel manufacturers won't release that, so you'll have to come up with it yourself. Be forewarned, you'll need some pretty beefy chunks of Al, and they aren't cheap. depending on the area, you'll be looking at more than $400 per wheel. It is possible to purchase wheel blanks, but they aren't cheap either. The benefit of the blanks is that they already have the bead profile. If you want some more info, let me know.

 
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cool thanks for the info.
my dads company buys huge chunks of metal all the time for their molds andwhat not so i;ll ask him how much it woold be.
can you explain more about the bead profile?
thanks again

 
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The bead profile, in my opinion, the hardest part. Like I said before, ideally, I would use a CMM to capture the profile. First, the profile is what the inside of the wheel looks like. When I say inside, I mean where the air that inflates the tire will be. You'll never see this part of the wheel when the tire is on there, but without a good bead, the tire will never hold pressure. I would take a wheel that you know is the size that you want, and VERY accurately measure the bead profile and use it in your 3D modeler (I use pro/engineer, but there are others that will work just as well). If you didn't know, a CMM is a machine that will scan in 3D the shape of an object. I have one in my shop, but they're not cheap. I think the FARO arm that my guys use is about $45k, but don't quote me on that. Needless to say, if your dad doesn't have one, you'll be there with the radius gage and a pair of calipers. If you wanted to make your own bead profile, you can do that, but it's not recommended at all. The profile not only seals that tire to the rim, but also allows mounting of a new tire. If there isn't enough clearance, it will be difficult, if not impossible, to mount a tire to the rim. That's enough of kicking THAT dead horse, but I do have another one.

What sort of finish do you want on these wheels? It is possible to polish the aluminum, but you'll have to send it out for that. By hand, this takes many man-hours per wheel, and the guys who do this stuff for a living earn every penny. I highly recommend a finish coat, either powder coat a silver finish (what many rims are anyway) or chrome. If you choose to get them chromed, it will cost you, heck, it'll cost you a good bit to get them powder coated. Just a warning.

Also, you might want your dad to do a little FEA on the design to determine if the wheels will hold up to daily driver conditions. The problem with Al as opposed to steel is that Al does NOT have an infinite fatigue life. What this means is that after fatigue loading of about 10^5 cycles, steel will have a certain decreased strength. It will retain this strength forever (for all practical purposes). Al, however, will continue to decrease beyond 10^5 cycles to the point of failure. So, this is something to consider. Again, FEA is highly recommended before you start cutting some chips. It will save you a LOT of time and money if your design isn't appropriate.

I have to advise you, there are a lot of people who have tried to make their own wheels. If you dive into this project, be prepared for it to take time and money.

One more thing, don't forget about the hole for the valve stem, that must make a positive seal too.

Later

CR

 
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thanks! lots of info!!
my dad has a catalog of metal stock suppliers and i will be researching this further.
i really want to do this because i like doing new things and i know i will learn a lot more about this stuff.
i use pro/e too. nice program.

 
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forged aluminum! I'm no mechanical engineer or rocket scientist, but I know what forged aluminum is, lol.

 
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Well, I AM a Mechanical Engineer. You can't fabricate a forged aluminum rim at a machine shop. Forged rims are made using very large forging presses that cold-work the material into the desired shape. Even if you're used forged aluminum billets to make your wheels, you'd still have to weld them (bad idea, very weak).

In my professional opinion, you're probably better off buying rims from a reputable company. Even cast aluminum rims aren't that bad. The problem is that you probably don't have access to the kind of equipment/resources to make wheels. At my work, we have a machine shop with several million dollars worth of equipment and I don't think I'd even attempt making a rim. Reason being is that wheel manufacture requires very specialized equipment...

my 2 cents!

 
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To design a rim, I am sure you don't need to be an engineer or rocket scientist. You are only conceptualizing the look of the wheel, I am sure with the help of computers, professionals, and maybe a company... your design can come to life.

 
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goodluck!

 
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Ok, I, as a mechanical engineer, could make a set of wheels with a $50k lathe and a $60k mill, but it would be cost prohibitive. I agree that it would be much easier and cheaper to purchase a set of wheels, but I do admire the goal. By all means, make your wheels, but please, be careful. I really would hate to see someone with such ambition damage their vehicle.

I will wish you the best of luck and offer to aid you with information as much as I can.

 
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making your own wheels is like if you were a doctor, would you operate on your self????

 
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Yeah bro, good luck with the rim project! I hope you succeed and make the best rims around...