9/3/2006: Bumper Assembly

Several weeks back, I received my chrome back from the platers.

For the most part I’m happy with the results- the bumpers look great, as do all of the steel parts.

The more heavily pitted pot metal parts had more mixed results. In some cases, too much detail was lost when they ground the parts down. In others, too much chrome/copper buildup made them difficult to reassemble.

But on the whole, I’m happy with the results. I can work with what I have, or can try again with those parts that did not come out acceptably.

I’ve started to put some of the chomed parts together, so that I can set the complete assemblies aside somewhere safe until the car is ready for them.

The first task was to put the front and rear bumpers together. Each is composed of three parts, a main bumper and two overriders.

The back sides of these parts were only lightly cleaned up before plating, so they are quite pitted and even a little rusty. I felt it was wise to paint them to prevent this rust from returning.

I wanted to use a rust preventative paint, and a silver topcoat. I initially thought about using silver POR-15 paint, but I ultimately chose to use Eastwood’s Rust Encapsulator instead. Like POR, it claims to work well on rough or surface-rusted surfaces and seal them completely. Unlike POR, it comes in spraycan form, doesn’t stink horribly, and is not sensitive to UV light. (POR-15 has to be top-coated or it will turn chalky if exposed to sunlight).

After a few coats of the Rust Encapsulator black paint, I topcoated with Reflective Aluminum spraypaint, also from Eastwood.

The results are obviously not chrome-like (the interior surfaces weren’t smooth or polished) but they’re at least silver and should be relatively well protected.

Assembling the overriders to the main bumpers was pretty straightforward. The only real challlenge was finding a replacement for the plastic edging between the two pieces.

The original material (on the left below) was a hard (but flexible) plastic. It turns out to be almost identical to plastic door edging, such as the “reduced size black” edging, available from Protekto.

I opted to switch to rubber instead. I figured it would be easier to fit and trim, and would look fine. I can always switch this later if it doesn’t work out. The rubber edging I ended up using came from McMaster-Carr. The part number was 8507K36 (neoprene rubber edge trim, 1/16” opening, 11/64” inside depth).

While I was at McMaster’s website, I also purchased a 6 inch length of rubber tubing, which I can cut into slices to make new bushings to fit between the bumpers and the body.

Here it is side by side with the original:

As you can see, the center hole is smaller, but it’s still larger than the bolt, so I may not have to enlarge it at all. We’ll see when it comes time to put the bumpers on the car.

The part number for this tubing was 8637K181 (neoprene spring rubber tubing, 1-3/8” OD, 3/8” ID, 75A durometer)

Chrome is hard to photograph, so I don’t have any pictures of the finished bumpers at the moment. It’s not that exciting anyway- they look like shiny bumpers.