Plus 2 sound Deadening

[Andy Hamblin]

Appreciate your opinions please - The interior is stripped on my Plus 2, awaiting carpets and underlay from Coverdales and currently cleaning up and preparing the floor and other panels for some sound deadening sheets to go on first. I went with Dodo Mat as it was significantly cheaper than the DynaMat and other top brand equivalents.

My question is - is it ok to put the deadening sheets directly onto the fibreglass or would you paint the panels first - if so, what with? I would quite like to paint them so there is a fresh clean surface for the deadening sheets to stick to, but I'm not sure what type of paint wouldn't react with the adhesive.

I have a good sized can of Hammerite Matt Black which i used in the engine bay - that washes off the brush with detergent and water, so wondering if that would be suitable?

Any thoughts welcome,

cheers,
Andy

[jono]

I painted my bare shell interior with a few coats of Gravitex which as well as having its own sound deadening properties was great to seal and stablise the bare fibreglass before applying the deadening.

I went original and used the 12.5mm thick dense jute sound deadening from Woolies - no problems at all with it sticking to the Gravitex treated panels with sprayed contact adhesive.

[Andy Hamblin]

I painted my bare shell interior with a few coats of Gravitex which as well as having its own sound deadening properties was great to seal and stablise the bare fibreglass before applying the deadening.

I went original and used the 12.5mm thick dense jute sound deadening from Woolies - no problems at all with it sticking to the Gravitex treated panels with sprayed contact adhesive.

Excellent - thanks. Did you spray or brush the Gravitex on? and can you remember how much you needed?

I did think about the original thick jute felt, but in the end decided to go with 2mm deadening sheet with 1cm thick latex backed wool underlay to support the carpet.

Now - what glues to what? I'm thinking that the deadening sheet is adhesive backed, so that will stick to the Gravitex painted panel, then the latex backed underlay will stuck to the deadening sheet with carpet contact adhesive and the carpet will just sit on the underlay with no adhesive - is that right?

[wotsisname]

the floor carpets are held in by the seat runners and some pop fasteners. the vertical panels that run along the sills, along the tunnel, up the footwells, etc are glued in place.
Might be worth trialing an offcut with your specific underlay. I used headlining quality contact (as described by Martrim) glue in some places. I have mainly used the jute type underlay but added dynamat in quite a few places. It seems to have stuck pretty well, but its not been long since I did it.

[The Veg]

Having just installed new carpets, here's what I did.

The fibreglass surfaces inside the car were in pretty good shape after a thorough cleaning. The rough surfaces seemed like a good key for adhesive, so I left them alone. The old 'felt' stuff got binned as it was dirty and smelly and generally a bit decrepit. Somewhere online I found some stuff called EZ-Cool which is 3/16" closed-cell polyethylene foam with a thin aluminium foil on both sides. Using some 3M spray adhesive, I covered pretty much the entire interiour with it. While probably not as good acoustically as the denser materials available, it is rather excellent thermally and best of all, a 100 square foot roll of the stuff weighs a mere 2 lbs vs the 20 or so lbs. of felt that came out.

I used the same adhesive to fix the vertical carpets and it seems to hold well as I used gobs of it, but time will tell yet how well it holds. The new carpet set came with some sort of modern synthetic-fiber felt to go under most pieces, but I only used it on the floor, figuring that the EZ-cool would be sufficient elsewhere but the felt would add some sonic damping for the floor as well as making the rather thin carpet seem a little more luxurious. I used the same 3M adhesive to fix the felt to the undersides of the floor-pieces.

The snaps for the floor-pieces were easier to get right than I expected. The female part that attaches to the carpet has a toothed ring that pierces from above then the teeth are bent after passing through the bottom bit, so once the male parts are screwed to the floor, just lay the carpet in place, find a where you can feel the male part underneath, stick the ring there, then hold the ring in place as you lift the carpet, then attach the bottom bit. It's easy to remove and try again if the placement isn't quite right the first time.

I couldn't remember how many snaps there were originally but the set I ordered from RD had eight. I ordered a second set then so that each of the four pieces that go in the foot-areas could have a snap at each of their corners. Probably overkill, but I've got some German blood in me so I like to make sure things hold together.

I've only done double-digit miles since the carpets went in but so far so good. The rear seat and adjacent trim-panels are still not installed so I'm still getting a lot of exhaust-note from behind me, but I suspect that installing those items will cut that quite a bit.

[Donels]

I have Dynamat which I will stick to the bare fibreglass, then the standard felt, then carpet. I don’t see the point of painting the inside of the shell when it will all be covered up. I do wonder though, where to stick the Dynamat so it’s most effective. The front of the transmission tunnel, footwell and bulkhead seem sensible and maybe the door skins and roof. Not decided on what to stick under the bonnet but definitely not the original style felt.

[Bigbaldybloke]

I’ve used self adhesive dodo mat for all the floor, tunnel and sills. It’s stuck directly to the unpainted fibreglass and seems well stuck, I’ve not decided whether to fit dodo mat to the roof before the headlining is fitted, any comments suggestions welcome. Only concern would be if the roof got hot in the sun and the mat started to come unstuck.
In the area around the fuel tank I stayed with the standard felt type sound deadening.
Undecided on what to fit inside the boot.

[nickruss]

I am embarking on installing Dynamat. Having cleaned out the boot, it's shocking how resonant the spare wheel well and boot floor are when you tap them! Like a drum.

Has anyone noticed a marked difference before and after soundproofing the boot?