Date:         Wed, 6 Mar 96 22:19:22 EST
Sender:       Vanagon Mailing List <vanagon@vanagon.com>
From:         jag@cs.rochester.edu
Subject:      Re: Rusting seams and other hard to fix rust problems.

Steve Johnson <sjohnson@pcocd2.intel.com> writes:

> So how does Bob H's sermon compare to the FAQ: Rustoration written by
> Ed Delaney?  Personally, I believe that two nice references are better
> than one.  I guess I should read them both, but I'm definitely out of
> my league here.  I'm sure Thom Fitzpatrick will lead me down the path
> of rust-free righteousness.  ;)


>From Bob's rusty seams sermon:

	When dealing with a rusty seam often times your only recourse is to 
	use chemicals but the most successful method is to remove the rust, 
	weld the seam closed and go on from there. 

>From vwairfaq:

	So basically you have rusted metal.  You can cover it up by
	cleaning off the rust, coating it with some rust inhibitor, cover it
	with body filler, paint it and wait for the rust to reappear some
	other day.  There are those that feel this is adequate given a tight
	budget.  The more aggressive types say you should always cut
	out *all* rust, replace with new metal, grind, sand, prime and
	paint for a long lasting solution.  This FAQ will assume you want
	to be a little more aggressive and do a thorough job, but will
	mention the "low dough" approach when appropriate.  

So basically both are bad news to us who think we can solve our problems
with a little sanding, naval jelly (phosphoric acid) and bondo. However
Bob's sermons does go on and tell us how to do a descent job without
welding.

>From Bob's how to fix the rusty windshield sermon:
(http://www.sky.net/~rmk/hoover/rustywindshield.html)

	If you wish to use fiberglass for the repair you should
	have some experience with composites and with
	the unique problems of bonding composites to steel
	structures. In most cases the fiberglass repair will
	result in a new, rust-proof flange only to produce
	rust under some other portion of the repair a few
	years later. Repair of an improperly done composite
	repair is more difficult than doing a welded repair. 

	The best composite repair is to build a mold of the
	shape you wish to produce using rigid urethane
	foam. You can glue the foam to the dashboard then
	sand it to shape. This will put gravity on your side
	as you do the lay-ups and fills. Covering the
	urethane with heat-smoothed plastic sandwich
	wrap will impart a glass-smooth surface to the
	finished lay-up. 

	The lay-up should progress in two steps, first
	laying up two or three layers of fine twill-woven
	six-ounce fabric saturated with a suitable epoxy
	resin. Surface with peel-ply and allow to cure. Strip
	off the peel-ply. trim for height, lay in a build-up of
	saturated chopped cotton fiber to form the fillet then
	do the finish lay-up with two or three layers, the
	first layer being the widest, the other(s) narrower.
	The stepped layers will be easier to blend in to the
	contour. If properly done, the repaired flange will
	have exactly the same contour as the metal flange it
	replaced but will be stronger and impervious to rust.

	Once the lay-up has cured, grind to finished size
	and blend the layers into the contours of the nose.
	Prime and paint. 

/Martin

PS Have you noticed how easy it is to follow inlined hyperlinks
when reading the vanagon@lenti list from Skips WWW page
(http://www.automatrix.com/~skip/volkswagen/vanagon-list/)
Just click on the link and you're there. Technology always
amazes me.