Custom Center Caps for Porsche Wheel [from CAD, prototyping to finish]

[Bfan]

Big like on this.....................

[geetee]

the original style looks perfect on the oz wheels....i think the new one's will look even better

[Nine8Six]

Originally Posted by geetee

the original style looks perfect on the oz wheels....i think the new one's will look even better

Always room for improvements, for any wheels. Cheap Plastic is dead man lolll

[Nine8Six]

Right... so this is what we're going to do.

I've just received the material that I've ordered y'day an hour ago (yey!). So we got a few pucks of Acetal, plenty of AL6061 (I think loll) and also found the few badges I had left in stock.

I'll run this quick and dirty in the R&D machines first, get a sample part anodized and assembled in-hands, and if all goes well (i.e. looks good, feel good, and fit/clamp well) I'll do the cam online with you guys for the shop floor's production machines (you'll see my little shopl). No point launching full-scale into making custom fixtures, softjaws, and all the other 'expansive' stuff required to get a small production run going. Besides the CAM work for those prod machines needs proven simulation before even starting-up and cutting anything. You'll get to see this as well but before - let's see this super duper center cap first.

Some grabs below of the 'quick & dirty' CAM work I've done yesterday evening. All I need left to do is adjusting the stock size in each part models and off we go - let's do a quick one (or two, we'll see how it goes). Estimate 1.5 ~ 2 days work.




Toolpaths and toolpaths only toolpaths. Finally we can cut something.

[steved0x]

Originally Posted by Nine8Six

Do you have any other color options for the center cap crest?

I have a black/silver crest and am currently running black/silver wheel crests, and I am thinking the gunmetal center caps with a black/silver crest would be a good match for me. Although the colored Porsche crest is classic and goes with everything...

Here is what I am talking about.

My hood crest:


My current wheel crests (made by stripping an old set of metal colored crests, then painting silver, then a very light covering of black that I then sanded off to reveal the silver underneath.



Something like that maybe?

[Nine8Six]

Originally Posted by steved0x

Do you have any other color options for the center cap crest?

I'll ask the manufacturer is he's willing to run a 'small' batch of silver for you. Not sure what you'll do with the remaining 496 crests though. Can I take a few off you?!

But seriously, that silver a good idea Steve (speaking of a humble look). I'll see what I can do to convince him to run this low'er for us and let you and other know. Got to wait until CNY is passed though... out of a billion+ ppl nobody other than myself works during that time of the year. Stay tuned buddy

(ps. thx for the idea btw )

[Anker]

How do you hold the part on your milling machine then you turn it over to mill the back?

[Nine8Six]

Originally Posted by Anker

How do you hold the part on your milling machine then you turn it over to mill the back?

• Toolpath Pic 1: Turning/boring the inside (ID) of the cap + threading a M52*1mm
• Toolpath Pic 2: Turning/profiling the outside (OD). Made a quick fixture with a OD thread that fit the M52*1
• Toolpath Pic 3: Milling/drilling using a 8mm flat endmill then fininshing the floor using a bullnose 8MMR1 cutter
• Toolpath Pic 4: Milling/4axis, Multiaxis toolpath going around the clips.

Just needed to machine one fixture; the one you see (quick&dirty) holding onto the cap thread and clamped between the vice jaws in Pic 3.

Missing are pics of the Acetal turning operations for the adapter. Using the exact same procedures as Pic 1,2,3.

Just need to see this cap first We'll do this correctly onto the prod machines later (coming week let's hope).

[Nine8Six]

Originally Posted by Anker

How do you hold the part on your milling machine then you turn it over to mill the back?

For you buddy Apologies for the half-useless explanation above lolll

[Nine8Six]

Some pretty good progress to share with you guys!

Besides the amazingly sunny and warm weather of today, I am very (very) happy about the result of this part. This goes to show how important proof of concept and part validation work are. Without CAE it wouldn’t have been half-possible to make this part successfully at first attempt. I would have had to blindly machine 5~10 different parts with different thickness, hoping it doesn’t fail, and worst… hoping for it to be clamping properly. Think about the time it would have taken without CAE lolll e.g. Model mods X10, CAM mods X10 and machining a prototype part X10 (ouch).

CAE add-ons are not cheap but do save a considerable amount of time/pain and most importantly; “add peace of mind”. We are now 100% certain this part will not fail when repeatedly inserted into the wheel hub, it will hold well and tight, and perform in temperatures ranging between -50 up to +50 Celsius.

Ladies and gent, I present you The Great, official and most advanced Center Cap wheel adapter In-The-World
^ (LOLL jeezzz… side effects of smoking CNC machine coolant fumes)





^ Some may find it interesting to see what was once a raw stock of Acetal, converted into a fully functional car part!




^ Here goes the final product (involves 2 turning operations + 1 multiaxis milling operation). Also showing in this pic is the precision thread required to mate with the main cap (I'll explain later how this 'permanently' thread locks)




^ Same part, upside down, showing the 5 clips.




^ View from inside a Porsche wheel (sorry for the messy pic!). The clamping is phenomenally accurate and amazingly strong. It does snap nasty in there and its goes in with a loud and clear “SNAP” noise. Absolutely love Acetal. Nothing better (dare to challenge me here). The bad news: the wheel will need to be removed off the car if you plan on removing your center cap. It just won't come out without a good push from behind the hub. Call it "Anti-Thief System"




^ Quickly snapped in my old Twisties wheel hub. Again, flawless. Sits flat and pressed onto the edge of the hub by-pressure as intended and not moving in any direction. Unlike the CGT style cap, this Acetal adapter concept will ensure that when you install your center cap, you'll be dead sure it is concentric to the hub and not offset. Something that was hard to acheive, but not impossible, with the previous CGT style design.




^ Here goes the two fixtures I ended up having to machine to hold the workpiece for the various CAM operations involved. The first fixture (nearest) will in use later this evening to machine the main aluminum cap.




^ Same fixtures. This one showing how I mount the hub adapter so I can machine/turn the OD profile and also this is how it mounts into the 4th axis rotary to mill the clip using the multiaxis toolpaths you’ve seen in the toolpath pic4 (previous post).


Enjoy!

[Nine8Six]

The last fixture I'll have to do later this evening (finally). Shows how I'll clamp the disk shape center between my vice jaws (they are in fact softjaws, made out of aluminum). You can see the CAM toolpath work on those for the milling operations.

If all goes well I'll be able to start anodizing this tomorrow late afternoon (shoulder hurt like crap though :/). We'll see, might have a fully functional prototype to play with this weekend!

[fridsten]

This is absolutely brilliant! I need a price and colour options immediately!

[Nine8Six]

Originally Posted by fridsten

This is absolutely brilliant! I need a price and colour options immediately!

haha thanks bud

RE colors, have a quick look at post#1. Expect the same line... gun metal, blue, red, black(my fav!), etc. Not sure I'll do the orange ever again as this never really turns out good anyway.

RE price, well you guessed: US$16,499 (each). Seriously, and until we've finished machining all of this, we won't know. We'll calculate the time it takes (in CNC minutes), calc the material cost for a kit, and figure out a end price for the kit based on this (add 5% for the machine electricity). Sincerely hope to get them cheaper than what a 'cheap plastic' OEM Porsche cap kits goes for wish me luck man

[rfuerst911sc]

LOVE YOUR SKILLS !!!! Keep up the good work . As soon as you can come up with your color offerings get them on here so people can start thinking about what to order .
I have some aftermarket wheels and I " think " the center cap hole is different than Porsche OEM . Will you be able to alter the diameter of the locking portion and maintain all the other dimensions ?

[Nine8Six]

Originally Posted by rfuerst911sc

LOVE YOUR SKILLS !!!! Keep up the good work . As soon as you can come up with your color offerings get them on here so people can start thinking about what to order .
I have some aftermarket wheels and I " think " the center cap hole is different than Porsche OEM . Will you be able to alter the diameter of the locking portion and maintain all the other dimensions ?

Thanks Rick! Tell you how I managed to get the standard Porsche wheel center/hub accuracy to 0.01mm tolerance (keep secret loll)

1. Fill/compress the wheel center with clay (or anything that doesn't shrink when drying)
2. Let dry overnight in a dry and warm room
3. Hammer it out from the back/rotor side of the wheel, so to keep the chamfer relief
4. Measure with a precision/metric vernier (caliper?)

If you can do this then I think I can help you out with custom. If not then based on luck bud

[Nine8Six]

And that is how one is spending his Chinese New Year eve! Making some cool car parts and drinking Champagne (Chinese version of it, of course )

In fear to destroy this masterpiece's reputation, I'll wait for tomorrow's day light to take much better pictures. No idea how to set a DSLR camera for a dark evening dinner table shot and photoshop just can't fix a drama like that. Oh, I've anodized a blue one also. Both look absolutely majestic.... wait and see!

Total happiness. Look & feel is surprisingly everything I was aiming for; low profile, perfect fit, humble but looking very expansive

[Nine8Six]

Too kind man, thanks!!!

[kjc2050]

Beautiful, Fred. Like the champagne flutes in the background; love the new product.

[Nine8Six]

Glad Chinese New Year's firework finally stopped. War zone stuff. Had time this afternoon to take those prototypes out for a ride in the front garden for their first photo-shoot. Guess it's official now "I really sux at taking pics" lollll

I do have medium-to-great skills in Photoshop however e.g that first pic is the bleu cap in grayscale (faked). Tried to mimic what it would look like in Gun Metal but it did canceled the shine that gun metal naturally comes with. Regardless, gives a good idea!

Using my old twities here as this is probably the most popular wheel in use these days. Gives a good idea of how those protrude out of the wheel and how the fit looks like. I promise I'll rig some rendering of the same wheel, and others (e.g. Carrera Sport 18s) both in silver and in black wheel colors for you guys to see.

Do we need laser markings on those? They look like they could do with some

[kjc2050]

They look great; love the profile. I agree that the laser markings would be a plus, if similar to those on the higher profile caps. Great work, Fred. Amazing.