Thread: Front floor panels - seals or silastic

Originally Posted by clubagreenie

Neoprene for wetsuits is open cell.

I think you need to check that. "Open cell" in wetsuit neoprene is a term used to describe a product that has been cold cut and has no smooth skin. It streches more, but is less durable. However the structure of the neoprene is still "closed cell". I'm guessing there's lots of marketing at play here!

However, I last wore a wetsuit (and drysuit) in the 1990's and it's been even longer since I made one - in the late '70's I couldn't buy a wetsuit suitable for kayaking, so I made a bunch of "long john" style single lined suits with enormous arm holes to prevent chaffing. As a result I'm not up to date, so I thought I'd have a check to see if the terminology has changed:

From Wetsuits 101 - What Makes a Superior Diving Suit/Wet Suit?
"The closed cell smooth skin neoprene is the most commonly used for diving suit" ----- This page also makes comment on what it calls "open cell neoprene", but whilst it states that open cell neoprene is slices of neoprene with no smooth surface seal, it seems to suggest that if closed cell foam is sliced it becomes open cell, which is of course nonsense (cutting the surface does not change the internal composition).


From About Wet Suit Materials
"In the Elastomeric Industry (the companies that manufacture rubber for all its various uses), the technically correct term for closed cell sponge rubber is expanded rubber. The cells are like individual balloons, holding gas and not allowing moisture to pass through as long as the cell wall has not burst. The chemical compound for sponge is the same as for solid rubber (like O rings and gaskets), but to create the sponge cells, the raw compound is mixed with a “chemical blowing agent”. Under the heat and pressure of the forming process, this additive decomposes and mixes with the rubber compound and generates nitrogen gas. As this reaction is occurring, the mixed batch is placed into an oven and allowed to expand into a bun from 2" to 4" thick. The bun of closed cell sponge rubber is then aged and sliced into sheets. These sheets are the basis of ALL modern neoprene wetsuits. So what is “open cell” sponge rubber? In the Elastomeric Industry, it is expanded rubber that is designed specifically to be lightweight and rebound completely after compression. This type of sponge rubber is typically used for sound deadening or absorption, not wetsuits." (The bold and underline are theirs, not mine)

This is way off topic though, so back to sealing LR floors!

Originally Posted by zulu Delta 534

I am with Dave 100% on this one. So a bit of water gets in but it also gets out just as easily. Try the same crossing with a supposedly well sealed vehicle and you will be parking in the sun for days afterwards with the doors open trying to get the mustiness out of it.
If you want a poofy vehicle that will float, dont buy a Land Rover.


Regards
Glen

Ha ha, well I know I'm going to get laughed at for this but I thought I would try and stop a bit of the water coming in and maybe as a side affect stop a rattle or two and block out a bit of road noise plus I was going to fit alfoil type insulation under there while I'm at it.

It's not that I'm trying to turn a tough car into a pussy but that I want to improve it bit by bit.

Thanks everyone for your advice as I have plenty to go on now, I just love working on the Series. These Rovers just get under your skin and are totally addictive, you just have to look at Mrs Ho Har's sig to justify that comment.

Last year my wife and I drove our military S2a 88" towing a small camper trailer from Brisbane to Corowa and back, in the warmer part of the year (3 days down and 3 days back), and we found that the noise and heat ingress from the engine bay was just a tad overpowering. As a result I have taken up all our floor and transmission panels and coated underneath them with silver coated rubber insulation, available from Clark Rubber and possibly any other rubber outlet. It comes in a variety of thicknesses and I chose 5mm. I also replaced most of the rubber grommets around the back of the dash and also insulated the firewall directly behind the engine.
The difference in heat and noise is extremely noticeable, even to the extent that we no longer have to shout at each other at 80+Ks, but I am happy to say it still lets out any water that gets in elsewhere, around any gaps around door sills etc..
Regards
Glen

I wonder if the sponge seal available from hardware stores for sealing house doors and windows would work?

I think I will give it a try

Originally Posted by chazza

I wonder if the sponge seal available from hardware stores for sealing house doors and windows would work?

I think I will give it a try

I have used it in the past - not as good as the neoprene I suggested above.

John

Originally Posted by Warb

What are we calling "mastic"? It's used to describe many things, from tile adhesive to tubes of Selleys "Butyl mastic" which I'd guess is closer to the product in question. But that would be very messy - it never sets so if the panels were removed it would need to be cleaned off with turps. ...

The reason I use it is because it never sets completely but forms a crust where it is exposed to the air, it also dampens noise because it stops vibration of one panel against the other. You apply it in a bead with a gun and is far less messy than silicone.

It is also very easy to acquire where some of the other rubberised seals have to be bought off specialist suppliers.

Butylmastic removes easily with a metal spatchela and then clean up the remnants with petrol or kero as you suggest.