MAX Update No. 78: Streamlined Headlight Covers

http://www.motherearthnews.com/green-transportation/100-mpg-streamlined-headlight-covers.aspx

I drove MAX to Ohio to cover the Vetter Fuel Economy Challenge, Craig Vetter’s competition for high efficiency motorcycles. I learned lots at the competition and even more on my tour across Middle America, but first I want to write about my preparation for the adventure.

0 78aFinishedCoverHeadlights aren’t generally a big contributor to drag, cars are generally pretty blunt in the front and headlights fit right in, but on MAX the headlight buckets are like a couple of flour scoops stuck on the front and they do disrupt the airflow. Fortunately the front fenders are replicas of Lola Mark 1 front fenders, and apparently they raced those at night back in the ‘50s (or they wouldn’t have headlights) so headlight covers are available.

Whoa! For a hundred and eight bucks each! Martha, my pills!

Okay, I’m calmer now. Since a real Lola Mk1 is worth a quarter million dollars (for a nice one) it shouldn’t shock me that the parts necessary to keep them nice are priced pretty…nice. It’s not like these are big sellers, and it’s not a highly competitive marketplace; it’s a fair price, it just doesn’t suit MAX’s budget.

Well lucky for me, the problem was half solved last December in MAX Update No. 64: Glowing With Pride, when I made some ABS plastic headlight bulb protectors for the inside of the headlights. The big differences between these covers and those are:

--These have to be clear.

--These have to be a specific shape.

--People are going to look at these.

078aCoverPatternThere are plenty of thermoformable clear plastics available, with brands like Plexiglass and Lexan, they’re available at building supply stores for some reason (making storm windows?) and $15 got me enough 1/16 inch thick clear plastic for four tries. I had enough scrap steel tubing to make a frame to clamp the plastic in (I think stapling it to a wood frame would have cracked it) and I had the fiberglass “donut holes” left from cutting the headlight holes in the fiberglass fenders.

78bSmooshedFrameI glued the fiberglass headlight thingies to some hunks of two-by-four, and clamped one of my plastic pieces (12 inch by 16 inch, if you’re interested in the specifics) into the frame. Then I softened the plastic with a pair of heat lamps until it was juuust right. How did I know it was just right? I tapped it with the round end of a combination wrench until it felt soft enough to smoosh.

 

When I liked how it felt, I pulled the frame out from under the heat lamps and quickly smooshed the plastic over the headlight thingie. After holding it still for a minute and muttering “I hope this works” several times, I released my grip and wow, cool, it worked.

I trimmed the headlight cover a little bigger than I wanted it, with a fine toothed saber saw blade, and taped it to the fender.

78cTraceCoverI traced the final shape on the cover with a dry erase pen (you could do this with a regular felt pen if you’re brave and careful), trimmed it to finished size, sanded the edge smooth, screwed it to the headlight bucket with some #4 wood screws and ta-dah! A headlight cover! All slick and sporty, and saved a hundred bucks. Too easy, I’m telling you. 

78dBubbledCoverMy hubris was short lived, because while heating the plastic for the other headlight cover, I waited too long and the plastic fizzed up like dropping a Mento in a diet soda; a million tiny bubbles that left the plastic white and opaque. My third attempt…well, it came out much like the second one, but I had the good sense to time the process with an oven timer this time, so for Attempt #4, I took it out from under the lamps ten seconds earlier and it worked; soft enough to smoosh, firm enough not to bubble.

All in all, this is a good fabrication technique, but expect to make a few scraps while you’re getting it right.

  Photos by Jack McCornack