Center cap size for M System turbines

[SixtyFo]

Hi all,

I've been trying to track down some center caps for the M system turbines on my M5, however it seems that the standard roundels are too small. A search online shows that there is a 70mm emblem sticker available, but no corresponding cap. Does anyone know that that is the correct size for these wheels?

[mottati]

do you mean just the roundel? The part that the roundel sticks to is integral to the center cover on the turbine. It's not available separately (if we're talking about the same thing).

So you just buy the sticker.

[BleedsBlue]

The sticker P/N Mike is referring to is 36131122132, if that is what you're looking for.

The cap itself is considered borderline unobtanium, as they've been NLA for several years.

I finally found a complete set of Turbine covers, and am considering taking one of the caps to a buddy with a 3D printer, laser cutter, and other Bond villain machines to see if he can make reproduction Turbine center caps.

[SixtyFo]

do you mean just the roundel? The part that the roundel sticks to is integral to the center cover on the turbine. It's not available separately (if we're talking about the same thing).

So you just buy the sticker.

I thought so as well but on the examples I have there is a ~75mm hole in the middle of the hub cap where the roundel goes. Looking on realoem the illustration doesn't show a different part. At the moment i'm considering just getting some generic caps and stick the emblem on.

[mottati]

are we talking about the same wheels? original M system 1, aka turbines?

On mine, the center is held in by a spring, you push in the roundel, against the spring, to pull the cap off. That part is not available by itself, as far as i can tell.

i.e. if you have no place to 'stick' the roundel decal to, you're probably going to need new caps (the whole assembly) or try to fabricate something

[SixtyFo]

Erk. I was hoping that wasn't the case. I may try some generic ebay blank caps and see how I go.

A picture for reference

[BleedsBlue]

Interesting, I don't think I've seen that part missing before. There is a cap that is definitely not available separately, and a spring behind it so you can push the cap in to remove the larger center cap.

[Jcbe34]

If you have access to a 3D printer over there I could potentially reverse engineer the two pieces you are missing and you could have them printed. Do you have the backing plate (bottom middle) or not? The top piece with the tabs is what holds the BMW emblem, that would be super easy to make, the backing plate would be slightly more annoying but not bad.

Msystem center cap by braswell.jonathan, on Flickr

[SixtyFo]

If you have access to a 3D printer over there I could potentially reverse engineer the two pieces you are missing and you could have them printed. Do you have the backing plate (bottom middle) or not? The top piece with the tabs is what holds the BMW emblem, that would be super easy to make, the backing plate would be slightly more annoying but not bad.

Unfortunately I'm missing both pieces. I'll try to find someone with a 3D printer down here to get something made up. Thanks for the pic! Had no idea what it looked like.

[Jcbe34]

I got my home license for solidworks and made this thing just because I was bored. Did you find a printer yet?

M-system center cap by braswell.jonathan, on Flickr

[SixtyFo]

I've been out of the country for the past 2 weeks but to answer your question it seems there are quite alot of 3D printing/prototyping outfits in Melbourne now. I'm trying to figure out what material to make this out of.

Edit: should really subscribe to my own posts -_-

[TheStigg]

Print them "FDM, ABS". Quite tough if done by a reputable outfit. I've had many parts printed by Forecast3D and results were excellent. Thicker is better for strength. Try to make features at least .1" if possible. Best to email the parasolid file (.sldprt, etc.) vs. doing a "save-as" 3D print file, will yield better results. Did they take all 4 caps? Most outfits with a decent Stratasys system can print all the parts in a single setup for economy of scale.

[Jcbe34]

Whenever I get some free time I can try to model the back section, it is going to be a little trickier to get right I think because of some of the smaller contours, but it would be worth it to try if you don't have any other options currently. Emailing centercaps to Australia is way cheaper than shipping

[SixtyFo]

Hmm for some reason forum notifications are not appearing in my email.....

Whenever I get some free time I can try to model the back section, it is going to be a little trickier to get right I think because of some of the smaller contours, but it would be worth it to try if you don't have any other options currently. Emailing centercaps to Australia is way cheaper than shipping

You're a lifesaver Jcbe34! I've managed to get in touch with someone with access to a Uni 3D so fingers crossed it'll work. The only other thing now will be sourcing the correct sized spring.

[hellrote36m3]

Whenever I get some free time I can try to model the back section, it is going to be a little trickier to get right I think because of some of the smaller contours, but it would be worth it to try if you don't have any other options currently. Emailing centercaps to Australia is way cheaper than shipping

Bumping this thread from the long dead. Jcbe34 do you still have the 3d models for the front and rear pieces on the turbine wheel centercap saved somewhere? I just acquired a set missing both pieces and would love to get the files to print rather than get the entire 3d printed ones off ebay. I never use this forum so I do not have the ability to PM you, I had sent you a message on FB (I believe) but it likely got lost in the message request folder. Last resort is bumping this thread and going from there.

TIA