Sunday, September 27, 2015

Bituthane and Bondo

Reason # 7239 why I hate winter . . . . yes we do body-work too.
Last spring when I was washing off the winter grime some of the paint came off the lower end of the fenders on my wife's VW. Seems they were rotting out from the inside. So on Saturday I figured it was time to tackle the nightmare.
Why does this happen? Piss-poor design. The plastic wheel well liner traps sand and mud behind it. That layer there is about twelve inches tall and about an inch thick. And you don't know it is there until you remove the wheel and the wheel well liner.
Time to get serious and yank the fender to work on it properly and clean the front end of the rocker pannel.
Which was also quite corroded
That is what came off the passenger side fender
A couple hours work with a steel brush on a drill gets me to bare clean steel.
 And the driver's side looks just as bad so it gets the same tratment.
Remove that fender too, and grind on it for a couple hours, mask it off and hit it with Permatex Rust-Prep from NAPA. Essentially phosphoric acid in a spray can. Turns all remaining rust in to magnetite an inert element that won't rust.
Passenger side gets the same treatment. Note how it turns black. That is the magnetite part.
Inside of the fender gets the same treatment.. good enough for Saturday. Time to call it a day and let the rust converter do its thing.
Next morning hit the inside of the fender with self etching primer and then rubberized undercoating.
Indispensable stuff
Rocker panels get the same treatment
Then line the inside of the fender with Bituthane (Bituminous-Urethane) AKA Ice and Water Shield
Which while adding some more protection inside, provides me some backing on the Swiss cheese steel to . . . .
Apply some Bondo (body filler for yous fureiners)
A bit of sanding and some gray primer makes it look good enough . . .
To coat with some more rubberized undercoating.
Sunday 5 pm got the refinished fenders installed and adjusted so all trim lines look even. There that should hold for a while. Don't know what a body shop would have charged for the job but I figure that it makes a fairly decent 13th anniversary present for Annie.


  1. Que buen trabajo Mike! si vivieras acá, con tus habilidades te habrías hecho millonario...

    1. Doug, I am a jack of all trades and a master of none. Without going to Argentina I am a millionaire, the only problem is its not measured in dollars ;-)

  2. You have a lot of very valuable skills. I am impressed by the different things you can do that most people have to hire out.

    1. Hey Harry, I suppose it is mostly due to need that I learned to do some things. Never had the money to pay others to do the job. And doing the job myself seemed like the natural thing to do. I can well imagine a body shop would have charged a couple grand to put new fenders on it and match the paint. The car is thirteen years old now and has 140K miles on it so that bill would almost surpass the value of the entire car. I have never pulled the fenders on a car before, but it didn't seem all that difficult after I got to digging in to the mess. I may look for new replacement fenders on line and have them painted out to match. Or we may look in to a newer car. But this will hold us for a little bit.

  3. Hi Mike, good job, to much work for me. I buy $500 cars and just drive them, looks aren't that important to me. Again, great job

    1. Hey John, I know what you mean. I have yet to ever buy a new car. I always buy used and wind up having to work on them. This is our "good" car. In this case this job was a stop gap measure to keep things from getting any worse. Once the rust gets in to the rocker panels it becomes a structural issue and it won't pass state inspection.