Beck TD, Part 29 - Hold My Bonnet, Please

Yes, of course, everyone reading this blog knows I'm not talking about a hat when I say, "bonnet." That's the British term for what we Yanks call the "hood," the part over the engine. At least in the old days, in Britain the "hood" was the convertible top. That makes sense, with its analogy to a hood on a jacket.

When I bought Beck, it was only running the top of the bonnet, with the sides open. To keep things from flying away, there was a leather strap - a traditional British way of doing:

Unfortunately, I didn't care for the implementation. The leather belt was held on one side with what looked like a screen door spring, and it didn't do a good job of holding the front of the bonnet after I added the rubber protective strip that was in the original design. I cut it off and discarded it.

I ran the bonnet sides for a while, but I did like the look and the easy access of the open sides. Recently, I saw a TD with open sides on a Facebook group, and when I inquired how it was done, the owner replied, "Bungee cords."

John Zimmerman helped me do some experimentation, and we determined that bungees have plenty of strength to hold the bonnet tight. I set forth to design a system that required no modifications to the car, and held both front and back of the bonnet securely. I devised a system that is held by the long brass rods that normally hold the bonnet sides, and attach to the latches for those sides.

Before I show you the picture, let me state that this is a prototype, and the eventual "final answer" will use black cords and be even more unobtrusive. But I plan to take Beck to the "Taste of Britain" show this Sunday with these neon colored bungees, unless there is a huge outcry by the vast readership of this blog:

The orange is bad enough, but even worse, the ones on the driver's side do not match. They were both originally yellow, but in using flame to melt the cut ends of the bungee, I managed to set one of them on fire!

*

At this point, I have 48 hours to redo it, if I can find black bungees. We'll see... For now, it has been a while since I did a "how I did it" post, so here's some detail on that mounting system. I do plan to remake the aluminum mounts, because it was an interesting machinist project and I want to do it better. For this prototype, I started with my usual ragged scrap:

Afer cleaning it up, I cut four pieces, and trued them up to be the same size. That made subsequent steps easier, because one setup would work for all four pieces.

I needed to round the tops to fit under the bonnet. I used a woodworking router bit for that, but I didn't have the right radius. For the next version, I'll buy the right bit so it's round instead of a cathedral ceiling:

Still working in the milling machine, I used a drill bit mounted in a collet to reduce runout, and drilled lengthwise. Unfortunately, those photos were blurry, but you can see the result:

One more drilling operation put a hole in the face for the bungee cord, with a heavy chamfer so the edge wouldn't cut:

Just for looks, I laid out a curved edge, trimming corners on the band saw, and then finishing on the sanding disc. A little sandblasting gave a more consistent surface:

The next step was to attach the bungee, and the Internet taught me that the best method was to use "hog rings," applied with a special set of pliers. This is the same method that is used to attach upholstery to the seat frame in cars. I didn't have those pliers, but it turns out that they are less than $10 at Lowes, in the garden center with the chain link fences:

These hog rings are 1-1/4" and are much too large. For the final version, I'll use stainless steel rings in 3/8" to match the bungee cord. I chose to double up the rings because of the aerodynamic stresses. Here's a detail:

So, even with the rough and ready finish and the bright cords, I'm pretty pleased with this. Give me some votes - should I take it to Taste of Britain this way, or put the bonnet sides back on until I can make it more pretty?

EDIT: Some weeks later, I did find some black bungee cords that basically disappear. I'm happy with these, and will continue with them until I find time, money and motivation to re-do the system in leather:

Continue on to Part 30...