MAX Update No. 73: Fenders Sans Benders

http://www.motherearthnews.com/green-transportation/100-mpg-fenders-sans-benders.aspx

This is what I should have done the first time, but I was so busy DIY-ing that I neglected that Ye Olde Custom Car Techniques are the best way to make car parts ONLY if you only want to make one part. Why would I ever want to make another one, you may well ask, and I would roll my eyes and say, “Well, duh!” as if I knew it all along. So here are three good reasons:

1. I might want to make another streamlined MAX.

2. You might want to make a streamlined MAX of your own.

3. I might do something stupid such as back into a mountain at a high rate of speed, and might need replacement rear fenders. Again.

MU73aFenderPatternArmed with the wisdom of experience (who says you can’t teach an old dog new tricks?) I began tooling a permanent mold so we could pop out fenders like cookies, though of course with fewer raisins.

The first step is to make a pattern, which is merely a full scale model of the fender, made with care and precision but without much concern for weight. Also, to make the right and left symmetrical, I cleverly made both fender patterns as one piece and cut them in half when I was done. Before I got to the cutting in half phase of the operation, kibbitzers and hecklers said things like “That’s sure going to be a narrow car” but I got used to it.

MU73bFenderMoldsNext step was to apply a mold release to the pattern, so the mold wouldn’t permanently bond itself to the pattern...ah, mold making isn’t news, it’s the same process I did on the nose last June. This was slightly complicated by a bit of “backdraft” which called for two part molds, but otherwise it was a walk in the park. A long walk, and it does take more time than making a one-off custom part, but only about twice as much time and that’s just for the first part. The next fender will only take a tenth as long.

The second photo shows the finished molds, with parts laid up inside them, waiting to cure (that is, for the liquid resin to become solid resin).

MU73cFenderPartAnd at last, the moment of truth! The mold is disassembled and the part popped out; an inside-out replica of the mold, which was an inside-out replica of the pattern. Now I can make as many cookie-cutter fenders as I want (and if I really wanted to, I could add raisins, but naah). Now all I have to do is get these fenders mounted in time for the Mother Earth News Fair in Puyallup. Yikes, that’s next weekend! I’d better sign out and get to work. 


Photos by Jack McCornack 

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