has anybody used spray on pick up bed liner, or the kind thats put on with a roller that can be bought at the parts store for sealer on a fiberglass firewall, and or the under side of a fiberglass floor ? I have seen it done on the underside of steel bodies. to deaden sound, and reduce heat.
There are better materials for deadening sound and reducing heat, but it will work. The WAY it will work is simply by adding mass to the fiberglass... which, for sound, reduces the resonant frequency of the material (that is, it lowers the frequency of vibration... hopefully below what your ears can hear, ie, < 20-25Hz). For heat, it acts as a simple insulator. Again, there are better products that are specifically engineered to address sound (more effective resonant frequency dampeners) and heat (materials that reflect as well as insulate).
I used Dupli-Color Truck Bed Coating on my truck bed. I applied it with a roller. It looked good for about a year. But after being out in the Pacific Northwest weather for a year, the coating changed color from semi-gloss black to dull grey. It became brittle and began chipping off. If I had it to do over, I would have saved up to have a professional spray my truck bed.
yes I have used the two part spray on liner kits and have been very happy with the results these are a lot better product than the roll on types.
I have used Raptor,made by U-pol with very good results.Sprays on with a cheap undercoating gun with a good appearance. No peeling after ten years.
Traditional sheet insulating materials like B-Quiet (used to be known as Brown Bread), Dynamat, ThermoTec, etc., offer a number of choices. They are typically made with a dense "tar paper" type of material, with sticky on one side, and a foil on the other. The foil helps with insulation, while the dense tar paper material does most of the sound deadening. You would apply it on the INSIDE of the floor pan and firewall... which assumes you'll be carpeting the floor when you're done, lest you have to look at shiny foil stuff all the time. Dynamat is probably the most well known (read "lots of expensive advertising"). I've had good luck with ThermoTec Cool-It and B-Quiet... both of which are usually priced better than Dynamat.
Next week I'm putting U-POL Raptor on the f'glass firewall of my 40 Ford PU. I have used the product on the running boards and it went on beautifully. As stated, there are other products that will address the heat and sound issues better than the bedliner product but from a good looks standpoint, you can make a firewall look great with the stuff with very little prep. The 2 part sutff is much more durable than the single componenet auto parts store liners. I also plan to use the stuff on the inside of my fenders to hopefully eliminate "stars" in the paint from stones off the tires. What make and year f'glass firewall do you have? Also, once you make the firewall look good with the liner, you can address any additional sound and heat issues with self adhesive products on the inside of the firewall.
I sprayed a two part bedliner under my 55 Ford, looks good, but it doesn't muffle sound much. I will be putting those stick on sound deadeners on the floor for sure.
The Jalopy Journal
