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Re: TR6 Rocker Pedestal Question

To: "Triumph List" <triumphs@autox.team.net>,
Subject: Re: TR6 Rocker Pedestal Question
From: "Nelson A. Riedel" <nriedel@nextek.net>
Date: Thu, 17 May 2001 14:39:37 -0400
> Why on earth are the holes in the rocker pedestals, for the bolts,
tapered?
> So that the top of the rocker pedestal has a properly sized hole to
> accommodate the bolt, and that the bottom has an oversized hole much wider
> than the bolt itself?  The entire length of the hole is rather cone like
> with a very visible taper.
>
> Quick measurements:
>
> Top, hole diameter:         10mm (0.39")
> Bottom, hole diameter:    12mm (0.47")
>
> Cheers,
>
> Kai (spending too much time staring at the pieces of his dismantled motor)

The pedestals are castings.  One explanation is that the hole in the casting
is made by placing a sand core in the mold.  The sand cores are made in a
mold and baked before they can be used.  The cores are tapered so that they
will slide out of their mold.  Brings back memories of working in a foundry
as a teenager --- a hot dirty thankless job.  Did provide some motivation to
study hard at university so that I'd never have to do that job again.  Then
I got married --- at times it's like working in the foundry.

Nelson Riedel
Granville, OH
76 TR6 (assembling after new paint)
68 TR250 (next project - new paint)
70 TR6 (all the parts in a pile ready to assemble)

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