Date: Wed, 25 May 2016 00:53:44 -0700
Reply-To: Neil N <musomuso@GMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Neil N <musomuso@GMAIL.COM>
Subject: further measuring of new GW brake shoes vs old generic brand shoes
Content-Type: text/plain; charset=UTF-8
So I found my spare backing plate complete with frozen (stuck)
wheel cylinder pistons. This provided a somewhat better means to
measure dimensions
of new shoes against old.
I cleaned the slots at wheel cylinder pistons and anchors then set top end of
each new and old set of shoes at nearly the same point at
wheel cylinder piston. Image: http://tinyurl.com/hlr335n
With my new brake resetting gauge, image: http://tinyurl.com/zvjw5h9
I measured ID at center of each shoe bracket http://tinyurl.com/h2jmowf
and OD at center of each set of shoes set up the same way.
I did this at least 3 times.
I also measured the shoes like this: image: http://tinyurl.com/jszuvfm
but this may not be an accurate means of measuring
given that the end of each shoe may have a slightly different geometry at
each end where they seat in piston and lower anchor.
Regardless, again, the new shoes were larger at OD.
Via three different means of measuring, I found roughly a 2 mm
difference between
each set of shoes; the OD of the new shoes was roughly 2 mm larger if not more.
Caveats:
Another contributor to all this *might* have been the anchor pins; I'd
previously added
"copper" antisieze to these pins. This *may* have "pushed out" the
pins a red hair. And,
in previously removing frozen pins from the old backing plate, marks made
by my pliers *may* have raised up the mating face at each pin. So, I
removed excess
anti seize then carefully filed down the edge at the face of each pin.
This made no appreciable difference. I really didn't think these were
contributing factors.
With the adjuster slightly slack, the f'ing shoes still rub a little,
drum turned by hand
no wheel installed, w-brake cables slack. All that in spite of
carefully filing down
the upper end of each shoe bracket (maybe by 0.5 mm at each, at most)
Basically, I'm going to install these parts and be done with it.
Or, buy new shoes from the vendor I got the new drums from.
Were it not for what I see as slight delimitation between the old shoes
and shoe brackets, (can be seen in image?) I'd reuse the old shoes.
Neil.
On 5/23/16, Neil N <musomuso@gmail.com> wrote:
> Right ok. I get it
>
> So I'm measuring the old shoe against new. First thing is that the e brake
> laver on the new shoes is 1 mm thinner. Assuming a properly adjusted
> ebrake lever would keep the adjuster bar in alignment, I doubt the larger
> gap between bar and shoe/ebrake lever is an issue. Depth of slot the big
> fork fits into is the same however. 11.5 mm by my measure.
>
> Measuring old shoe against new, ironically, lining plus steel bracket
> thickness end up being identical.
> Regardless, it's proving tough to get consistent measurement from mid point
> of shoe lining OD to
> a straight line from each contact patch at each end of the shoe.
> So far though it seems im seeing a 1 mm difference but. could be full of
> doo doo on that measurement.
>
> I traced an outline of each end of each shoe bracket where they fit into
> lower pin and wheel cylinder piston. The bottom portion is nearly identical
> so I transferred a measurement of contact patch shown on old shoe, to new
> shoe. It's roughly mid point. My lower pins are somewhat worn
> though. The upper end is nearly the same shape.
>
> I know this seems like overkill, and my methods are highly suspect, but
> if I'm correct about these particular new parts fitting so close from the
> get go, it's possible some other shade tree could install the parts only to
> end up with glazed shoes and drums.
>
> YMMV though.
>
> Neil.
>
> On Monday, May 23, 2016, Dennis Haynes <d23haynes57@hotmail.com> wrote:
>
>> As for taking some material off the shoes plates to make clearance I
>> meant
>> to say DON'T take any off the bottom. The trick with these is to maintain
>> as good a contact patch as possible. In creasing the clearance by taking
>> off some material at the top will be compensated as the lining wear by
>> the
>> adjuster. Since there is no adjuster at the bottom leave the loser shoe
>> mountings alone. Recall most shoes needing t have the bottom shimmed out.
>>
>> Dennis
>>
>>
>>
>>
>
> --
> 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>