IMO, maybe improved, certainly not fixed. Still sounds tinny. If the "fix" was mangozac's part reference, that would explain the marginal improvement. To be fair, part of my objection sounds more like window glass clunking than door tin reverberating. This fix is essentially as effective as the "fixed" roof motor water resistance. (I can't bring myself to call it waterproofing)Adamski said:
'Clunky' doors
- Thread starter GazDerby
- Start date
Maybe, but at least it's known quality and IMO why skimp for the sake of maybe $40 on the quality of parts for my Z4? Who knows what the adhesive quality is like on the cheaper stuff - the last thing I want is it peeling off and have to be redone!sam1832 said:
So I'm looking at a 457mm x 813mm sheet for each door. Can anybody confirm if that will be enough?
Mangozac said:
I agree that the product has to be good quality. It'll sit in the sun getting up to very high temps and needs to be durable and not all end up in the bottom of the door.
^ X2. I have had multiple different makes of thes bitumen plates in my hands in the car part store and the idea and quality is all alike. All suitable for high temperatures as well.
Only thing that does make a difference is the thickness of the bitumen sheet. You do not want that to be too thin, because then it does not do the job properly, on the other hand you also do not want it to obstruct any parts in the door. Until that point is reached and apart from weight issues generally speaking: thicker is better.
457mm x 813mm per door should do the job. However, while you are at it, you may also consider soundproofing the plastic bits surrounding teh front windscreen. You only need to remove four screws to take the plastics bit out and sound isolation there does take away a large part of the squeakiness when hittinig bumps, etc. If you would want to do that as well, I would suggest ordering an additional sheet of bitumen foil. If anyone would be interested, I could post some (telephone quality) pictures tonight ...
Only thing that does make a difference is the thickness of the bitumen sheet. You do not want that to be too thin, because then it does not do the job properly, on the other hand you also do not want it to obstruct any parts in the door. Until that point is reached and apart from weight issues generally speaking: thicker is better.
457mm x 813mm per door should do the job. However, while you are at it, you may also consider soundproofing the plastic bits surrounding teh front windscreen. You only need to remove four screws to take the plastics bit out and sound isolation there does take away a large part of the squeakiness when hittinig bumps, etc. If you would want to do that as well, I would suggest ordering an additional sheet of bitumen foil. If anyone would be interested, I could post some (telephone quality) pictures tonight ...
sam1832 said:
I don't care what brand it is, so long as it's decent quality.
I managed to purchase large offcuts at great prices from my local audio dealer, so didn't pay market prices. No need to as it's hidden
Bitumen sheets seem so primitive. We're essentially talking about roofing tar. Is this really the best material? Acoustics are tricky, often defying common sense and sometimes even science. It works, so are we afraid to try something else? I wonder how a spray on foam might work. We have different densities available, anything from polyurethane insulation to truck bed liner. Can be layered to almost any thickness, possibly with different densities. Lighter and relatively cheap. Main problems I see are application control and access.
I'm not really suggesting someone actually try this in their car, more just throwing out ideas for the sake of discussion.
I'm not really suggesting someone actually try this in their car, more just throwing out ideas for the sake of discussion.
Dynamat (and the BMW product) are butyl, not bitumen, so is a little more modern than "roofing tar" 
Like I said, I'm happy to pay the premium for a product that has a known name and reputation in order to avoid the possibility of things like the adhesive breaking down. As CJ says it will get quite hot and having to redo it would be a massive pain the the butt.
The spray on liner would probably work quite well, although I wonder if it would turn out heavier than the butyl sheet? Like you say though, application would be difficult and messy...
Like I said, I'm happy to pay the premium for a product that has a known name and reputation in order to avoid the possibility of things like the adhesive breaking down. As CJ says it will get quite hot and having to redo it would be a massive pain the the butt.
The spray on liner would probably work quite well, although I wonder if it would turn out heavier than the butyl sheet? Like you say though, application would be difficult and messy...
^ If you stick to materials such as Dynamat, Conrad, etc. - in other word the stuff actually meant for this - you should count on anything between 3.5 kg and 6 kg (depending on brand and thickness) per square metre. Given that if you stick to one layer it will be difficult to add more than 0.25 m2 per door you should count on anything between 0.875 kg and 1.5 kg per door...
Regarding the install pictures I will dig deep into my picture directory later today ...
Regarding the install pictures I will dig deep into my picture directory later today ...
It is not really a lot of hassle though and when done right the improvement can be major.
Only thing that actually needs to be done is to remove the door cards and the foam behind them. Heat the material up a bit by laying it in the sun for an hour or so, or using a hairdryer and simply adhese to the innerside of the outer part of your door. Work simply around the rest of the bits in the door. Put everything back in reverse order and you are done.
Costs should be no more than EUR 25 when done by yourselves...
Without removal of the window mechanics, roughly halfway through the process left side:
Right side: with removal of the window mechanics (started to get squeaky, thus replaced) and with all the sound insulation fitted:
By the way: the brown stuff in the door is grease, not rust ...
Only thing that actually needs to be done is to remove the door cards and the foam behind them. Heat the material up a bit by laying it in the sun for an hour or so, or using a hairdryer and simply adhese to the innerside of the outer part of your door. Work simply around the rest of the bits in the door. Put everything back in reverse order and you are done.
Costs should be no more than EUR 25 when done by yourselves...
Without removal of the window mechanics, roughly halfway through the process left side:
Right side: with removal of the window mechanics (started to get squeaky, thus replaced) and with all the sound insulation fitted:
By the way: the brown stuff in the door is grease, not rust ...
So by removing the foam, you are actually replacing the OEM insulation? So in the end there is no weight gain then? Might do this when I have a lot of time and reaaaally bored I don't mind the noise that much, but it looks like a fun DIY and it will make the doors sound more solid...
I don't mind the noise that much, but it looks like a fun DIY and it will make the doors sound more solid...