The cells are closed and prevent any capillary action or moisture absorption Dear syntax Appreciate your post being constructive - thankyou, your advice is often well founded, but I offer the following in response here. The expansion rates are very high to ensure complete filling of the rails etc. In fact they are so high that the instructions for most foams are to make sure that you leave one end open or the pressure will explode the container! If you look at any video of foam filling (such as the one previously shown), you will see and understand that this is not a problem at all given the high expansion rates. (The stuff comes out of every hole including the ones you weren't aware of - :rofl You could actually conversely and technically say that welds may not be proper unless checked by X-Ray as well (which is why Aircraft industries check them under X-Ray) but this is not practical either as you suggested Polyurethane actually absorbs vibrations! This means that stress on other connected suspension components can actually be reduced and quietened/ protected as well using this material, whereas there is no give at all with welds lone as vibration, is known to place stress cracks into welds and / or metals as a whole and result in failure. There is no capillary absorption of moisture with polyurethane! The high expansion rates ensure each cell is closed off to the next and hence this is the main reason why I am very interested in this myself, mainly for rust prevention of the inside of the rails (these cars are quite old and I live near the ocean) Polyurethane is used and has been used in suspension for many years, its properties and value are very well known, hence its popular and common use. Its not if we just discovered this new compound? The only real known problem that exists with polyurethane is, it can squeak if it is incorrectly fitted or the wrong compound type is used. There are hundreds, if not thousands of compounds of polyurethane and this is the difficulty we/I am having, in that I am trying to find/ determine the best one based on its properties. Clearly there are ones that are even lighter and more suited to pillars and others that are heavy and rigid and more suited to chassis rails and the insides or tension bars/ struts etc. The choice is huge and whilst there are many that are well suited to the application, it is difficult to find the best one given there are so many! In simple terms I offer the following: You cannot compare welds to Polyurethane in rails etc. The two are completely different in action and purpose. Polyurethane does not replace welding, just as welding does not replace Polyurethane but Polyurethane does complement and can even protect welding due to the absorption of vibration. For improving suspension - I personally would recommend the combination of both of them with split welding and polyurethane filling in chassis, suspension components. The heaviest Polyurethane foams are still very light compared to any metals, when weight of foams are considered, the text becomes pedantic and trivial in reality - foams are light in weight - its a basic fact! (this is not directed at you, but rather everyone else - densities have already previously been given ) More to follow soon..........probably weekend.....still waiting for responses - some of these distributors are really slow! Thanks and Regards JC
So when are you starting sales work for this foam company?? :rofl: Just kidding, keen to see how this pans out.. Not that i can see there will be any measurable outcome....
Yep - I guess I will end up being a volunteer salesman - lol Hey Champ ! Soon as I can find the exact product for my chassis rails I will volunteer :rofl: At first I thought it might be feasible, but after doing some research into the various foam compounds it seemed quite viable given the properties of these foams, then when I found out that GM, Ford, Mercedes and many other large manufacturer have already been using this foam for many years with reported engineering success in strengthening chassis components I began to have faith in this. I tend not to rush into things and will take my time into further researching these various compounds, I have found some really rigid foams over the last week with very high densities, but I am still looking to make sure I get the best one for the job as there are so many to choose from. I am happy to be the first cab off the rank with the right one and have confidence that independent test results will prove this is quite viable. I have found out that nearly all the foams availableare excellent in preventing rust in chassis rails and this alone has made me a salesman for when I choose the right compound - :rofl: Any other benefits I will take along with it, such as vibration absorption / noise reduction and strengthening. Many people underestimate vibration absorption but we all have seen welds crack, solid bars fatigue and components fail and having a compound that seeks out and absorbs these high and low pitched vibrations makes a significant difference over time. These cars are getting fairly old now and over recent years I have seen many people report fatigue, so foam is fairly viable for these cars in a long term perspective. When I upload the stats on the weekend, you will be able to see the specs on the properties and I will upload some videos where testing is being done with vibration absorption and strengthening. I am sure that you will find the stats very promising indeed. As I pointed out in earlier posts it doesn't replace welding seams, it complements them and also helps protect them with the unique vibration absorption properties, besides its obvious original intended purposes. Major manufacturers do a lot of engineering research and if its good enough for them, then it sounds viable and is good enough for me to try, given foam is cheap, light and has unique properties that has led to it being used in suspension components and chassis parts Cheers and Regards JC
Better start cleaning out those dusty ass 20 year old rails, ensuring all rust and paint has been removed so your foam has proper adhesion.
Yep - its not for the faint hearted Adhesion is not the problem given the expansion rates are between 30%-60 (depending on the foam compound - looking at 30% so far), but yep its going to be a job cleaning them out! My plan is to use a round wire brush on piece of very thick long wire then use a compressor and blow the crap out as much as possible with some force. Then use a spray gun with rust converter and blast it both ends just to ensure I get the whole lot covered and neutralise any existing rust. Wait two days for the chemical reaction to fully complete (magic stuff that rust converter - I used it in the back section before - it leaves a protective coat as well), then the foam can go in. Its not a small job for the faint hearted though - but its the things we do for the love of a bloody Z! :rofl: Cheers JC :zlove:
Rust converter will remove paint too and leave a dusty etched phosphorusy suface, which is perfect for you.. So win win
