What wheels do you use??

[Gavin]

We are in the market for a new set of rims and I was just wondering what other people are using. I know lots of the US teams run Keizer wheels, but I was wondering if anyone know of other 13 inch race wheels. The European teams seem to have more choices. Just let me know what you guys are running.

Thanks,
Gavin
Rutgers Formula Racing

[Gavin]

We are in the market for a new set of rims and I was just wondering what other people are using. I know lots of the US teams run Keizer wheels, but I was wondering if anyone know of other 13 inch race wheels. The European teams seem to have more choices. Just let me know what you guys are running.

Thanks,
Gavin
Rutgers Formula Racing

[Colin]

why don't you try making some we got some centre's cast in magnesium and some 2 piece rims spun up it was very cost effective and we got them lighter than the keizer rims we modelled them off

[jack]

where did you get the rims halves made? could you get any amount of offset you wanted?

[Colin]

we got them made locally i think it cost us just under $800 aus to get 8 sets of rims spun and under $500 aus to get 8 centers cast and we could get any offset we wanted. the more rims we got spun the cheaper they were

[Denny Trimble]

That's a pretty good deal. We'll have to look into this, maybe even a group-buy thing for the spun rims.

My centers are done and being mounted with tires now, time to add spinners...

[Gonzo]

Colin have you had any problems with magnesium centres? As I understand it this USAC are banning use of magnesium wheels due to safety issues. From my dealings with them they are very susceptible to fractures. However this is from use on speedway cars which tend to bang wheels and drive on rough tracks.

Some one else, I think it was the guys from Auburn Tech (might be wrong on that though), told me they had problems with magnesium centres buckling.

Just interested to hear your input. Magnesium is the way to go if it stands up to the loads.

[Colin]

We have never had a failure but noticed that the Keizer centers we bought had begun to crack, partly the reason why we made are own. the keizer wheels had been used for four years. We changed our design to try and reduce the cracks and so far out wheels are holding up very well

[mizzouracing]

We run Kodiak wheels. They may no be the lighest wheel available but they have worked well for us so far.

[Ben Hatfield]

Colin, I was just wondering if you could tell us where you got your rims spun up as we are currently chasing a set.

[Colin]

hey ben check out your e-mail http://fsae.com/groupee_common/emoticons/icon_smile.gif

[Ben Hatfield]

Thanks Colin

[Buckingham]

We ran Kodiak Wheels 2001-2002. Every center showed fatuige stress cracks at every spoke within 2 years. Last year we switched to Keizers and couldn't be happier.

Donavan Haidinger
University of Wisconsin

[Denny Trimble]

Really? That's surprising to me. We just sh!tcanned a bunch of Keizers that had badly cracked centers. Add to this the fact that the rims would bend if you swore in their presence, and we weren't very happy with them.

The Kodiaks have worked well for us since 2002, but we buy a new set each year. I made some lighter centers this year, I'm pretty proud of the weight savings while maintaining the stiffness and stress levels of the original center. And upgrading the material (7075 instead of 6061) should help fatigue life too.

[James Waltman]

Denny,
How did your centers come out? Will you post some pictures? I can't find it now but the last picture I saw looked like the outer profile was going to be a little off and lead to harmonic problems.

[jack]

denny, have you tested your wheels physically, or FEA? are you just using the rim halves from the kodiaks? we will probably be needing some custom halves next year, ill get to you about that when the time comes--that is if we dont make our own carbon halves http://fsae.com/groupee_common/emoticons/icon_wink.gif

[Joseph]

These are the centers we are using. The only problem we have had is finding time to make them on the CNC.

http://students.ou.edu/K/Joseph.D.Kliewer-1/wheel_center.JPG

[Denny Trimble]

Joseph,
Sweet! Center-lock and everything. Looks like you're using Keizer rims. Mine are for 4-lugs, and Kodiak rims.

Jack, the design is based on FEA, with loading through a dummy tire contact patch and wheel shells, so the load is distributed properly onto the center.

James, no problems with harmonics. My process plan was:
1) CNC mill center bore and lug holes / pockets
2) band saw into rounds
3) lathe work to get taper and step
4) finish on CNC, doing the outer pattern first (see movie).

Here are some pictures, and a movie (right-click, saveas, uses DivX) (http://students.washington.edu/dennyt/fsae/wheelcnc.avi)

http://students.washington.edu/dennyt/fsae/wheel_group.jpg

http://students.washington.edu/dennyt/fsae/wheel_iso.jpg

[James Waltman]

Denny,
That video is great and the finished product is awesome. Nice job. Was the coolant off for camera reasons? Is the Z-axis travel done with a programmable quill feed? What feeds were you able to use – tough to tell with the sped up video. With a little more editing you could use that video as backup for ridiculous CNC times in the cost report. Where is that picture of them mounted on your 2003 car in square form?

[Denny Trimble]

Thanks James. The square wheel pic is here:
http://students.washington.edu/dennyt/fsae/squarewheels.jpg

That mill is capable of flood coolant, but the guy who runs the shop isn't into high-volume stuff, so we can only use mist coolant. You can see that it's going really slow in the first setup (10X video speed on everything), that was 10 to 15 in/min. On the second setup, I ran the whole thing at 25 in/min with a 1/2" end mill, .100 cut depth, and ~40% stepover. The z-axis is automated (quill feed), but the drill functions weren't working because of a post-processor issue. So, you see me drilling 8 holes at a time, then countersinking them, then another 8, then 2. That's because the machine can only remember 8 points at a time if you type them in at the console http://fsae.com/groupee_common/emoticons/icon_wink.gif Not good for production, but I spent a day trying to get drilling to work before I decided I could do it semi-manually.

We're planning on a first drive Saturday. When do you expect V35 to be rolling again?

[clausen]

We're using two piece carbon and aluminium wheels. You've probably seen the idea done elsewhere previously http://fsae.com/groupee_common/emoticons/icon_smile.gif

[Charlie]

Wheels are one of our few carry-over items this year. We looked around and may have gone with something new, but for the improvement we couldn't justify the cost. (Hurting for dough right now).

Here are our wheels from last year:

http://www.auburn.edu/~pingiii/temp/carandtrailerdubs.jpg

[ozzy]

nice piece of photoshop work!

[Farls]

That's a lot of stagger there - even if you are used to that oval junk http://fsae.com/groupee_common/emoticons/icon_wink.gif

[Andreas]

Joseph, that is really a nice piece of work. I like!

Clausen, do I need to say how happy I am to hear about your wheel design?! Made any prototypes yet? I´m really looking forward to see how your rims turn out!!

Andreas, Chalmers, -02, -03

[ozzy]

i loved the cnc video, you guys did really well. the path looks a bit clumsy at times, but a really good finished product! i wish we could do thigns like that! dont have time really either

[MercerFSAE C. Burch]

Joseph... Cool wheels and video, but what was the actuall CNC time? @ $70/hr was it really cost-effective to make your own centers?

-Chris

[Denny Trimble]

The CNC video is for my wheels (U. Washington), Joseph is from U. Oklahoma. The video was sped up 10X for entertainment value. Flood coolant in production, and a bigger, faster, stiffer mill, would allow faster feeds and speeds than what I was running.

[Mike Shaw]

here at texas a&m, we run kodiaks at the competition due to the polished bling factor, but use both kodiaks and keizers for tuning and testing and so we can bring a few extra sets of tires out when we practice.

i designed some new ones last year that saved a couple of pounds for the whole set and were stiffer in a camber deflection mode, but time restraints limited us to not using them. i modeled them after bbs and used a 4 lug pattern, and the ended up looking like the rims on a neon srt-4, which i thought backed up my design. maybe next year...

[James Waltman]

Chris,
At $70.00 an hour CNC machining is ridiculously inexpensive. We probably have a couple hundred CNC parts on our car and they are all inexpensive in the cost report (also due to aluminum only being $0.75 per pound). Our machines are bigger, faster, stiffer, and have flood cooing. We can rough material at 300ipm with a .250 inch depth of cut. The machine we use the most has a rapid of 710ipm. With a good 1 inch carbide endmill we can cut at well over 100ipm with .150 inch depth of cut. We are just students learning the machines and I feel that we are pretty conservative with our machining feeds and speeds. Mike Waggoner and Travis Garrison got very good at it and they were starting to push the machines a bit. Ozzy mentioned clumsy tool paths. I have been guilty of this. There is very little incentive to streamline the toolpaths on a run of 4 parts.

Several of our graduates started Pro/CNC a CNC machine shop here in town. These guys are very good. I know that their Kitamura HMC will rapid at 2000ipm, has 15,000rpm spindle, and a very cool pallet rotation system (it takes 2.5 seconds).

Denny,
Can you comment on the cost comparison vs the centers from Kodiak? I can't find a price on wheel centers only. Do you mind sharing what you put in the cost report?
I think that yours could be machined in well under 20 minutes each. Even at 30 minutes each they would only cost $35 dollars for machining in the cost report – pretty inexpensive

[Brent Howard]

James,

I'm not sure what the Kodiak wheel centers cost, but our Keizer 1.75" splined centers are $175 US each.

Brent

[Denny Trimble]

We put the wheels at 30 minutes CNC time each, so $35 each for CNC cost. Add material, etc, and it's pretty cheap. I don't have a cost for Kodiak centers, but buying shells vs. complete wheels is about $400 to $500 savings on a set, so 100 to 125 each. We ended up paying less out of pocket, and with a lower cost report value, by making our own. I'm glad I did it, too, because I learned more about our 3-axis mill, and earned permission to use it after-hours, which is a first. We'll be making more parts on it in the future. I'll probably look into eliminating the lathe work the next time I do wheels, and try surfacing the conical taper on the mill.

We seriously need to look into getting less expensive shells. We paid about $700 for a set of Kodiak shells only. I don't want to touch Keizers, we've bent every single one we've ever bought.

[Sam Zimmerman]

Denny,

Do you mount your own tires? I have heard alot about Keizer wheels bending but we are on our second year with ours and have had not problems with bending, but I won't let any machine touch our wheels. My only complaint is how easy the beads unseat on the Keizers.

[Brent Howard]

We get a shop to mount our tires and it can work out really really well if they use the right equipment. However in the last year we have had 3 rim halvs wrecked by shops that don't use the correct equipment. Luckily they have paid for replacements though.

Brent

[Denny Trimble]

Yeah, we used to have our own tire machine, which is probably why the Keizers got bent http://fsae.com/groupee_common/emoticons/icon_smile.gif Although I seem to remember one set coming out of the shipping box semi-square.

One tire shop did manage to mangle our first set of Kodiaks, but they replaced them and said "don't come back with those". Now one of our team members works at a tire shop and sweats a pint every time he has to mount them up.

[Charlie]

The Keizer wheel durability thing has been beat to death. I mounted every single one of our Keizers and they are all bent. The machine I use is a very good one as well.

Unless you are putting your wheels on a balancer, you might not even realize they are bent. We are still using our bent Keizers on our old cars. I just think that the bent wheels have to make drivability a bit more unpredictable. I measure the runout on all our wheels every time I mount a new set of tires.

[MikeWaggoner at UW]

The golf cart wheels Western Washinton uses are only $40 or so apiece, and with the center cut out (or reinforced) custom center can be made.


<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Denny Trimble:

We seriously need to look into getting less expensive shells. We paid about $700 for a set of Kodiak shells only. I don't want to touch Keizers, we've bent every single one we've ever bought. <HR></BLOCKQUOTE>

[RaID]

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Andreas:
Clausen, do I need to say how happy I am to hear about your wheel design?! Made any prototypes yet? I´m really looking forward to see how your rims turn out!!

Andreas, Chalmers, -02, -03 <HR></BLOCKQUOTE>

ill fill in for Clausen, we're still at the design stage and first of all we need to get some carbon, so unfortunately no prototype yet,
im sure you guys will be some some of the first to see them

[RagingGrandpa]

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by James Waltman:
...their Kitamura HMC will rapid at 2000ipm, has 15,000rpm spindle, and a very cool pallet rotation system (it takes 2.5 seconds)... <HR></BLOCKQUOTE>
SPOILED BRATS!!!!

Haha, I couldn't be more jealous actually.