I really appreciate you commenting on this Dennis.
I checked online for this type of wear, and saw other examples of same,
but no real explanation.
What concerned me a little was that all 4 pads showed the same type of wear.
i.e. were the rebuilts just that crappy? Conversely, since all 4 wore the
same,
maybe that's just how they wear on a caliper using that type of piston.
However. I just found this samba thread:
http://www.thesamba.com/vw/forum/viewtopic.php?t=385646
It has great pics showing the type of caliper piston I refer to AND
offers explanations suggesting the silencing shim helps keep the
piston from turning. i.e. pistons with recesses have to be kept in a certain
position, vehicle side specific.

If I had some excellent images of these shims, (mit tabs) I'd make my own.

Neil.

On Mon, May 25, 2015 at 6:10 AM, Dennis Haynes <d23haynes57@hotmail.com>
wrote:

> Since those pads had a silencing pad on the back you wouldn't need the
> silencing shims or plates. The uneven wear is somewhat common on these
> brakes. Why I really don’t know. My guess is that it is somehow due to the
> pads heating at that edge more than the other side causing increased wear.
> Another possibility if the calipers being rusted in the guides where the
> pads sit preventing them from moving freely. These side surfaces need be
> cleaned and some brake grease applied to prevent rusting. Check that the
> pad plates can slide freely for the full range of wear.
>
> Dennis
>
>
> -----Original Message-----
> From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf
> Of Neil N
> Sent: Sunday, May 24, 2015 10:39 PM
> To: vanagon@GERRY.VANAGON.COM
> Subject: Re: Brake Pads Worn At An Angle?
>
> So it seems some Bay bus owners have had the same wear pattern.
> Here's an image showing one set of my pads. Ends with narrower pad
> material mount at lower end of caliper (called "leading edge" ?):
> http://tinyurl.com/l54ana5
> An image showing back of a pad. It looks the piston face near corners at
> recess are contacting the pad back more than rest of piston face:
> http://tinyurl.com/mpxq53t
>
> This all may be of no consequence but i do wonder if a lack of shims is
> causing this wear and if it's compromised braking effectiveness.
>
> Neil.
>
>
> On Fri, May 22, 2015 at 7:34 PM, Neil N <musomuso@gmail.com> wrote:
>
> > Hi all.
> >
> > Teves calipers on an '81 bus.
> > PBR pads, no silencing shims installed.
> > Is it abnormal for brake pads to wear at an angle? (front to rear)
> >
> > My guess is "yes" but why? Is this due to recess at piston face?
> >
> > All pads show nearly identical wear.
> > Wear is at an angle, front to rear with a difference of ~ 2mm.
> > Pads had at least 50% lining left.
> >
> > The pistons compressed back in easily.
> > I put a piece of 1/2" plywood in place of each pad.
> > Mark from piston appeared even.
> > (did this to make sure pistons moved in/out)
> >
> > --
> > Neil n
> >
> > Blog: Vanagons, Westfalia, general <http://tubaneil.blogspot.ca>
> >
> > 1988 Westy Images <https://picasaweb.google.com/musomuso/New1988Westy>
> >
> > 1981 Westfalia "Jaco" Images, technical
> > <http://tubaneil.googlepages.com/>
> >
> > Vanagon-Bus VAG Gas Engine Swap Group <http://tinyurl.com/khalbay>
> >
>
>
>
> --
> Neil n
>
> Blog: Vanagons, Westfalia, general <http://tubaneil.blogspot.ca>
>
> 1988 Westy Images <https://picasaweb.google.com/musomuso/New1988Westy>
>
> 1981 Westfalia "Jaco" Images, technical <http://tubaneil.googlepages.com/>
>
> Vanagon-Bus VAG Gas Engine Swap Group <http://tinyurl.com/khalbay>
>

-- 
Neil n

Blog: Vanagons, Westfalia, general <http://tubaneil.blogspot.ca>

1988 Westy Images <https://picasaweb.google.com/musomuso/New1988Westy>

1981 Westfalia "Jaco" Images, technical <http://tubaneil.googlepages.com/>

Vanagon-Bus VAG Gas Engine Swap Group <http://tinyurl.com/khalbay>