Machining cast wheels, damaging?

[Johnny Blaze]

I had posted on another site about my wheels for my Iroc that I had the Hub hole enlarged to fit.

Someone replied,
"I hope that they are forged wheels as boring out a center hub can destroy the integrity of a wheel"


Any truth to this?

[lvrpool32]

Hmmm, not buying that as ALL cast wheels are machined afterwards, either to make the mouting face flat, the lug holes, machine the hoop and to make any size center bore (I've never seen an "as cast" center bore, how the hell woudl you make them hub centric???)

My 64 Riviera has pretty much the largest hub bores out there and all three of the wheels I have used all had plenty of meat on them to get machined out (2 types of Coys wheels and TT2's). I woudl say as long as your not doing something silly in hoel size...your fine.

[John Wright]

Maybe they were concerned of overboring the center bore to where there is very little material left?

[LS1-IROC]

Got a pic of said hole? Most likely, it will be fine unless the hole had to be so big that it created thin walled sections.

[Johnny Blaze]

I will get pics up.
The hub is 2" thick, only 1" was machined and it was not even enlarged more than the other 1".

[Johnny Blaze]

Here is a pic of the unaltered wheel.


And here is the machined one.


front view of unaltered wheel


front of machined

[Apogee]

Well done...I'd run it.



Tobin
KORE3

[Johnny Blaze]

Thanks,
the guy that said this is an engineer according to his info.

The fronts were machined out just enough to fit the hub, so the fronts are hub centric, now.

[Twentyover]

Thanks,
the guy that said this is an engineer according to his info.

Doesn't mean he's a competent engineer. Just remember that for every guy that graduates at the top of his class, there's another engineer that graduates at the bottom of his class. When someone come up with aline like that,always ask them to explain it. If they can't,you can ignore it.

And I'm an engineer. Won't tell you where I graduated
.

[Johnny Blaze]

Well done...I'd run it.

Tobin
KORE3

Coming from you, thats quite a complement! Thanks!

I am waiting on an explanation from this guy. If I get one I will be sure to post here.

[LS1-IROC]

I see NO problems with that what-so-ever. I agree with above statement.

[Johnny Blaze]

Sure looks like my lug nut holes, and the back mounting flange were machined at some point as well!

[John Wright]

Roll on. I think they will be fine.

[csouth]

They're fine. The weight shouldn't be on the center of the the wheel, but on the studs. Plenty of metal left....

[Johnny Blaze]

Here is the guys reply after I posted pics, and 3 or 4 people questioned his comment.

"Theory is that a cast wheel is strongest when it is at the dimensions made when it is at the factory; cutting material can reduce the integrity of the hub mounting area and cause cracks that will lead to failure. If you are talking taking a file to scrape a little bit of paint, that would be fine, some wheels can't take an extra mm of bore before they start to fail, others can go 1/4" and be fine.

And yes any wheel failure is going to be catastrophic, so check your wheels all the time for cracks around the hub area. "

[LS1-IROC]

I better go check my cast aluminum block for cracks...I'll be right back...

[Johnny Blaze]

Thats what I was thinking as well.

Funny thing, this guy has a 'performance shop' website that offers work. The only product listed on his site is custom forged wheels for 3rd gen f bodies.