More Soundproofing!

[defcon1]

I decided to get crazy again...and Lee suffered because of it...

Today, I decided to improve my car's soundproofing...so, off to Lee's place at 9.30 in the morning with a boot full of Insuflex. Also bought some bitumen tape...the normal kind that you use to waterproof roofs...some time during the day when I decided that the bitumen under the fenders was not thick enough.

To cut a long story short...

a) Doubled the layer of insuflex under the carpets. Fitting back the mouldings, seat belt, centre console and seats was a biatch...but we managed it...by cutting away whatever was blocking the moulding from going back in, and some interesting gymnastics...or was it yoga...from Lee...

Results : Engine noises, and the noise from my Y-pipe almost eliminated.

b) Doubled my original layer of bitumen under the fenders, concentrating on the area adjacent to the absorber mountings.

Results : It really works wonders. With my speedworks absorbers, the ride has always felt harsh. Even the smallest bump translated into a shock that went through everything in the car. I even thought my dash needed to be taken out and reinstalled but now, no more shocks, and my dash doesn't shake any more...

c) Tripled the layer of insuflex in the boot (did this last week, and it makes a heck of a difference). My boot has a mdf floorboard, so just stuffed everything in, and screwed it back in place...makes the insuflex very compact and cuts out almost all the exhaust noises.

d) Put one layer of insuflex on top of the plastic moulding in the front wheel well.

Results : I hardly hear my front tyres anymore... Amazing that one layer of compact poly sponge can do so much.

To really test it, I drove the family to the airport and back. Driving it felt very much like driving a beamer. Everything felt solid.

Only one problem....

My back...and Lee's, I'm sure...could use a rub down... :sad_smile:

 

[ongteckweng]

time for a good massage from the spa? hehehe
gr8 stuffs chris...i wish to do it on my wife's kenari but dont have the time to do it...:(

 

[defcon1]

For a kenari...probably one day enough...and will be done better and faster than mine since I now know exactly how to do it...

Working on wifey's Myvi next... :smileL:

 

[honggas]

Deffy, How much did you spend on the Insuflex?

Also, can just 'tampal' ? or does it have to be sort of strategically placed ?

 

[ongteckweng]

For a kenari...probably one day enough...and will be done better and faster than mine since I now know exactly how to do it...

Working on wifey's Myvi next... :smileL:

so u wanna help me or not??? kekeke
lunch on me la...

 

[Ultimate Cefiro]

deffy.... im interested in..... plz share v me.....

 

[defcon1]

I never had time to take any photos. But I'll try to explain how it's done.

You will need :

i) Bitumen sheet and tape. For bitumen sheets, get Raammat from Grexer. Do a search on the ICE forum for him. For bitumen tape aka Flashing Strips, visit some hardware shops that deal with contractors. The old type hardware shops will carry it...it's tape for sealing roofing. Get as wide as possible and as thick as possible. Usually comes in 2", 3", and 4" sizes, and about 2mm thickness x 10m length. For the Ceffy, one roll of Raammat, and maybe 5 - 6 rolls of flashing strips will suffice.

ii) Insuflex sheets. There are several thicknesses from 5mm - 20mm, and come in self-adhesive or plain (no adhesives). The self-adhesive kind is very expensive, and so is the very thick kind. I opted to use 9 - 10mm sheets (2m x 1m) as it costs less than half the price of the 20mm sheets. To get the thickness, just use 2 sheets, and for some areas, one sheet is enough.

iii) Heavy duty cutters

iv) Cheap scissors - single use, then throw away. If you want to salvage, you will have to wash this in petrol.

v) Contact glue. Buy in cans. 1 litre should be enough

vi) Plastic spreader/scraper. Any hardware shop will have. It's used to cut dough in baking.

a) Let's start with the booth area. This is the easiest and can be done @ home. You remove everything from the booth. The floorboard cover, the spare tyre, the side mouldings, and the plastic moulding at the end of the booth so that you can see all the metal. For those of us, like me, who have a mdf floorboard, remove it, but you may leave the mounting frame behind (the strips of mdf that they screw to your floorboards to screw the floorboard on. It may be a good idea to borrow or buy a proper clip remover so that you don't damage any clips that you take off. Else, have a handfull of spare clips handy.

b) Cover all the metal in bitumen. For the big expanses of metal, you can use the Raammat. For the narrow areas, or at the ends of the bitumen strips, you can use the flashing strips. The flashing strips are conveniently thin strips to help you with the confined areas where cutting a sheet into shape is difficult and will result in wastage. For the absorber mounts and spare tyre well, you might want to put in two layers of bitumen. Don't worry if you overlap, or if the work is not so neat. Bitumen is malleable, and will conform to the shape you press it into. Also, having a hair dryer or heat gun handy is a good idea, as this will allow you to heat the bitumen making it more pliable, and also increasing it's adhesion properties. Try to avoid covering any nuts or bolts you may find as this will make removing items difficult later on. Also, do not cover the rear fender areas with bitumen i.e. the areas behind your jack, and the hole on the other side, as this will make bodywork difficult later on, if you have minor dings or scrapes. It will be easiest to cut the bitumen with the scissors mentioned earlier, but you can trip the excess bitumen, once attached, with cutters.

c) It is not necessary to cover every inch of the metal diligently. What you are doing is increasing the metal's mass slightly so that it does not resonate so much when it is hit by sound waves. The theory is as follows. Steel tends to resonate at high frequencies, and high frequency sound is difficult to intercept since it is high energy waves. By adding a damping material i.e. bitumen to the steel sheets, what you are doing is making the steel resonate at a lower frequency. When this metal surface is hit by sound waves, it will now resonate at a lower frequency, producing low frequency sound waves that are easier to intercept.

d) Once you are satisfied with your handiwork, cover every inch you can of the surface with Insuflex. Here is where you will need your heavy duty cutters and contact cement. For floorboards, if you cut accurately, you only need a dab of contact cement here and there along the edge and in the middle to make it stay. You do not need to cover the entire insuflex sheet with glue, as this will make it very difficult to remove later if necessary. You only want it to sit on the metal. Insuflex does not do the job of damping, it is there to intercept the now converted low frequency sound waves. Hence it does not need to sit firmly on the metal. For the jack area, you might just elect to stuff the material into the holes, and it will do the job. For the vertical areas...absorber mounts etc., you will need to cut the insuflex into pieces and assemble it, like a jigsaw puzzle. It will be easier this way than to glue entire pieces on...unless you get the self adhesive kind, but it will cost you more than double.

e) Finally, then you're done...go have a cup of coffee, and a smoke (for those smokers), and rest your back. Give it about half an hour for the glue solvent to dry off a little. Then proceed to put back your mouldings. The fit will be tight, and some clips may not go back, since they are old, and will no longer hold pressure. Also, the moulding material is brittle and may crack at the clip points. I solved this issue by cutting some "insuflex washers" to spread out the force and managed to get everything in.

f) The hatch...is optional. I didn't apply bitumen here, as it would be messy, and the hatch tends to get hot, so Raammat may not cut it. Dynamat has a version for roofs and bonnets, but it is bloody expensive. Also, I reckoned that it did not need any bitumen, since most of the sound waves come from below, where you have already built a sound barrier on the floorboards of the booth. I did, however, carefully insert a layer of insuflex behind the ribs of the hatch, and then clip the cover back on. Be careful not to put too much pressure on the hatch release cable or it will get stuck, and you will not be able to open your booth from inside the car.

Close up everything, and then take the car for a spin and see if you can still hear your muffler. This exercise can be completed in about 4 hours. The interior...which will be the next installment, will take you a day. After that, the front fenders...you will need the help of a mechanic since this involves removing the front fenders.

 

[ongteckweng]

deffy...when u wanna help me do my kenari? hehehehe

 

[defcon1]

I am perfectly willing to HELP...any Saturday that I am not travelling. Just organize with Lee when he can spare a space to take out everything in the car. Priority will be to get my wife's Myvi done as soon as Grexer delivers my current order of Raammat...

 

[ongteckweng]

okie...deal...wait till u r done...im next...huhuhuhu...but u will need to let me know okie...

 

[cgui]

wah .. good process to see this happen .. full sound proofing ..

 

[Ultimate Cefiro]

deffy.... then find 1 satuday then we can have small TT as well..... errrr...... how much would it cost for the whole job n how long would it take?????