Beck TD, Part 66: Wind Wings, cheap!

 Well, this is yet another complex and time-consuming fabrication project to save a few bucks. My lovely wife enjoys an occasional cruise in Beck TD, but she says she doesn't like to be "buffeted." There's just so much you can do in a very open car with a flat windscreen, but I did notice that both Charlie and Cor run "wind wings" on their windshields. Here's a close-up from an old photo I took of Cor, with the wind wing annotated:

I asked Cor if his helped with buffeting, and he said, "Not much. A little." Well, since keeping the missus happy is definitely high on my priority list, I still decided I would give them a try. I checked Moss Motors, and they had a set in stock. Including tax and shipping, $149.97. Yow! That's a lot for "a little" help. I resolved to make my own, and asked Cor to send me a couple of pictures of his mounting hardware. This one shows how the hinges mount:

It's hard to see from this angle, but there's a set screw in what looks like an open hole, and that's what holds the hinge to that protruding rib on the TD windshield. I started making a design of my own that would mount similarly.

I started with a rough piece of scrap that was literally retrieved from a dumpster at Thaddeus Stevens Technical College, and once it was clean and square, I moved to the band saw to cut four slices for four hinge blocks.

I did some drilling on each block for the hinge bolt to pass through, and rounded the corners of the outside edges. Then, came the learning experience. The gizmo pictured below is a "slitting saw" and its job is to cut deep slits in hard metal. It is a VERY slow process - each piece took about half an hour to cut. 

But the cuts were very clean and square, and after drilling and tapping for set screws (I used two - belt and suspenders) the hinge blocks were complete:

I decided to fabricate the hinge parts out of 1/2" angle iron. I cut away part of one leg at the band saw, used the milling machine to make it square and flat, and then drilled for the hinge bolt. I needed left and right pairs, so I had to pay careful attention to orientation. In the right-hand photo, I'm rounding the end of the hinge so it will rotate without hitting anything.

Inevitably (at least for me) I got confused and drilled and tapped the holes on the wrong face of one piece. I used screws and permanent Loctite to fill the holes, and later sanded them flush.

After painting, they looked pretty good.

Time to start messing with the Lexan wings. I had never worked with clear material that thin (2 mm) so I pondered how to align it on the milling machine to drill the hinge holes precisely 1.5" apart. I put a chunk of baltic birch plywood in the mill vise, lifting it clear on parallels. I then used a 3/4" milling cutter to plunge a clearance hole, and then milled a pocket with "fences." Doing it this way ensured that the fences are precisely aligned with the movement of the mill table. This worked so well, I may duplicate it in metal with a replaceable wood insert for drilling. 

There was another learning experience, however. One of the first holes grabbed the material, lifted it, and broke off a corner. After that, I used a hammer, held close to the drill bit, to keep the material from rising. That little lesson added $7.62 to the cost for replacement material. Oh well... there was some left over for some future project.

Other things learned about Lexan: you can cut even this thin material carefully on a table saw with an 80-tooth blade. I used that same blade to rough out a curve, freehand, and then refined it on the disc sander. The slight burr left from cutting and sanding was carefully scraped away with a utility knife blade, held at an angle to the edge to keep from scratching the face.

There was a bit more fussing - re-tapping the painted holes, shortening screws, bumming 1/4-28 nuts off of Phil (Grade 8 nuts! Fancy.) But finally I could assemble, and they look just fine.

I had a test in mind. Without the wind wings, the wind around that flat windshield would start to lift a baseball cap off my head at around 45-50 MPH. My hope was that I could get to a higher speed before I needed to remove the cap. I took Beck TD up on the expressway and drove 60 without losing the hat, so I'm calling this a firm success. 

Using scrap and some purchased supplies, out-of-pocket was about 20 bucks, plus maybe 10 hours of rather enjoyable shop time across two weeks. Here's hoping my wife likes it too. We're going cruising tomorrow, so wish me luck!

UPDATE: After a long cruise, my wife declared the experiment "...a definite improvement!" I'll call that good enough!

Continue on to Part 67....