Dynamat

[213532]

When I stripped my car for restoration almost two years ago, the original interior sound deadening was pretty thrashed so I removed it. I had purchased the sound deadening kits from Bill Perrone when they were still available. The pan was in great shape with only a couple of dents and a few holes mistakenly drilled for seat belts (previous owners were unaware of the factory seat belt mounting locations) so it was cleaned, seam-sealed and painted with black Rustoleum. Sound deadening was then installed. The underside of the pan was also cleaned and painted then sprayed with Wurth undercoating.

The future conservators of the car will be the ones to determine if this effort was effective for preventing rust.

I've helped stripping a few cars and if there is no sign of rust, we've left the original sound deadening intact.

[Meissen540]

I have seen a car that had Dynamat in it, and water got behind it. The water never had a chance to evaporate, and there was a brown concoction of rusty water. Dynamat is not an end all to prevent this from happening. The OE jute may not be as effective at sound deadning, but at least it has a chance to dry out.

[VirtuallyReal]

Has anyone considered spray-on alternatives, like these two?

For heat:
http://www.lizardskin.com/car-ceramic-insulation.html

For sound:
http://www.lizardskin.com/sound-control-insulation.html

When i removed the original insulation from my car, i too found the remains of that "brown concoction of rust and paint", and since my car will be a driver, not a concourse car, i care more about the protection of the metal than the originality of the insulation, specially when we are talking about elements that will be mostly hidden from sight.

Same principle applies for the engine bay: instead of the tar impregnated panels, my ideal scenario would be something i can spray on, thus eliminating the possibility of water/moisture being trapped between the metal and the insulation...

what do you guys think? have anyone tried something like this on a 356?

[merbesfield]

[quote="VirtuallyReal" post=40419]Has anyone considered spray-on alternatives, like these two?

For heat:
http://www.lizardskin.com/car-ceramic-insulation.html

For sound:
http://www.lizardskin.com/sound-control-insulation.html

When i removed the original insulation from my car, i too found the remains of that "brown concoction of rust and paint", and since my car will be a driver, not a concourse car, i care more about the protection of the metal than the originality of the insulation, specially when we are talking about elements that will be moostly hidden from sight.

Same principle applies for the engine bay: instead of the tar impregnated panels, my ideal scenario would be something i can spray on, thus eliminating the possibility of water/moisture being trapped between the metal and the insulation...

what do you guys think? have anyone tried something like this on a 356?[/quote

I plan on using this product for my car. From what I have read and seen it seems much better than trying to use heavy tar sheets and also has the added benefit of rust prevention due to it's sealing nature. The only thing I am not sure of is how and if it can be used under the car. It says it can be sprayed under the car. The question is does it go on in addition to the Shutz (I was planing on using Wurth SKS Stone Guard). SKS is water based so these products may work together ok or in place of. My guess would be Lizard skin first followed by Shutz for the finish appearance. Then a top coat as usual for finish protection.

[bbspdstr]

Guys, the bottom line is to lock moisture out from the metal. Cleaner is better than rusted surfaces, but the theory of POR 15 is sound; loose rust off, "encapsulate" the remaining rusted surface with a waterproof coating. Any epoxy primer can do that.

Just be sure to scratch/abrade/scuff the steel and then the epoxy (or catalyzed urethane)surfaces, old or new before any texturing or gluing.
Automotive stone guard, truck bed liner or other tough textured product needs "tooth" to hold up.

I have posted before; these final steps 30 to 45 years ago included fish oil primer from Rustoleum ("damp proof red") or a similar bridge paint and then the good old 3M Body Schutz. Years would go by and the only thing was to touch up the Schutz that was blasted off where tire 'stuff' got to it. The primer was still doing it's job. Nothing really adheres to Rustoleum except more of the same. Please don't ask why I'm not still going that way....'cause I really don't know!

-Bruce

[Don C]

+1 on "damp proof red" now called "Rusty Metal Primer".
Bruce, if it worked before why change.

[roy mawbey]

Mark,

I had the same feelings as you after I scraped off all the factory covering off the underneath floor and wings ( fenders ) The then 10 year old car's metal was back to shiny steel and after welding the relatively small areas that needed it I thought long and hard before painting it with a number of coats of Zink based primer then hammerite paint, then only after more thought a coat of rubberised underseal.

I did the underseal because of stones hitting the paint surface underneath. I really wanted to leave it painted but 40 years on pleased on my decisions. All the factory coverings are still present inside the car the engine bay and front boot. Pleased I never had to remove them.

But Mark... I know you wish to use the car as a runner like me, however, I have the feeling after all the work doing that you might well be like me and countless others, always looking in sky for rain clouds before turning the ignition key

I can say the underneath of mine seems little different to when I finished it around 40 years ago. I have touched in a few areas where stones have hit it but overall because the car really never gets wet the car remains as it did all those years ago.

All the paint, all the covering, will only work really well if the car remains on the dry side. Its a shame, but that's how it is. Thank goodness the BMW is zink dipped, more 356 would be here now if they had done that then.

Roy

[merbesfield]