hey good point !!!
surprised that didn't occur to me ...but as you say ...
it being perfectly round and centered is very important.

I was thinking more along the lines of tiny fractures occurring at irregular
cutting points,
though I thought the guided router idea sounded great.
though that is not 'centered' as in how something could be cut
concentrically on a lathe.

40 per wheel sounds kinda high too. Many wheels have had the center bores
enlarged by good machine work I believe.
Last one I looked at looked factory done, it was that clean and centered
looking.

but a nice home made hole there could give the guys in the tire store a good
laugh and brighten up their day, and make the wheels unbalanceable.

----- Original Message -----
From: "pdooley" <psdooley@verizon.net>
To: "'Scott Daniel - Turbovans'" <scottdaniel@TURBOVANS.COM>;
<vanagon@GERRY.VANAGON.COM>
Sent: Monday, February 01, 2010 1:33 PM
Subject: RE: PDX Machine Shop Recommendation?

>I think Scott may be talking about poor wheel balance due to uneven
>material
> removal, but something else to consider is how wheel balancing machines
> work- a cone shaped chuck is tightened into the wheel bore.  If the bore
> hole is not perfectly centered the balance machine will not accurately
> determine proper balance.
>
>
> -----Original Message-----
> From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
> Scott Daniel - Turbovans
> Sent: Monday, February 01, 2010 4:02 PM
> To: vanagon@GERRY.VANAGON.COM
> Subject: Re: PDX Machine Shop Recommendation?
>
> I would much rather have it machined properly.
> factors are integrity of the wheel, balance, etc.
>
> hog it out by hand if you must, but I don't think much of that idea.
> Wheels are extremely important from a safety point of view.
>
> and please have long enough wheel studs or wheel mounting bolts,
> and the right ball face to match the wheel.
> it's more fun to do it right I think.
>
>
> ----- Original Message -----
> From: "Jake de Villiers" <crescentbeachguitar@GMAIL.COM>
> To: <vanagon@GERRY.VANAGON.COM>
> Sent: Monday, February 01, 2010 11:39 AM
> Subject: Re: PDX Machine Shop Recommendation?
>
>
>>A 1/2" shankcarbide router bit works very well on aluminium, but its not a
>> job for a neophyte!  =)
>>
>> On Mon, Feb 1, 2010 at 11:13 AM, Sudhir Desai
>> <sudhir.desai@gmail.com>wrote:
>>
>>> why not just measure 7mm around, and use an angle die-grinder to
>>> remove the material~
>>> just make sure to keep the metal cooled by a stream of water, or tool
>>> coolant.
>>>
>>> Sudhir
>
>