11/25/20

Car Roof GoPro Camera Bar - Build photos.

Pretty regularly, I like to mount a GoPro camera in my car. Sometimes its to record footage of an autocross event with my car club, or to capture footage of a scenic group drive with some other gear heads. The ideal position for the camera (for me) would be right over my shoulder. So, windshield suction cup mounts are convenient, but not quite right. So, I've been wanting to build something that would put the camera where I want it, but A) without drilling new holes in the car and B) without resorting to adhesive pads of goo, which either fall off as soon as the weather gets chilly or leave permanent spots of funny discoloration where they once were. I have a friend who positions the camera right where I'd like to, but he has a harness bar in his car (kinda like a roll cage, but not exactly), and just clamps the camera to that. I don't have plans to install a harness bar or roll cage, so I need another solution.

My car is a two-seater hatchback with a unique cargo net thing that rolls up out of the firewall behind the seats, hooking into two metal brackets mounted into the roof. It's a bit like a window shade, but upside down. After a friend (the same friend with the harness bar) pointed out that these brackets screw into the chassis of the car, and are easily removed to reveal a threaded 6mm hole, I immediately began designing in my head an aluminum strut, mounted across the ceiling of the car. These photos document the build.

Once removed, the factory hard point reveals two holes: one tapped for 6mm and one that's just a hole that locates with a stud on the back of the factory piece.

The factory hard point (passenger side). The cardboard on the right was used to mock up the shape of the box I'd have to make, in order to duplicate the fit of the factory part.



Test fitting the mockup of my cardboard box section.

The face of my replacement bracket will do away with the garment hook and extend the width of the face, to give me options to mount the camera bar. I always have my tuxedo sent ahead of me with my butler, so the garment hook has never been used anyway.

These are actually upside down. The spiral part that looks like someone's ear canal is the hook area that receives the flanged end of the rod that forms the top of the cargo net "window shade".

Cardboard mockup of my complete pocket bracket. Now, to duplicate it in metal.

The faces will me from 1/16" aluminum. It's easy to work.

Instinct tells you to cut the shapes out first, but experience has shown the wisdom of cutting the harder, interior contours out of the larger piece, and THEN cutting out the parts.

Needle files allow precise finishing of the exact shape of interiors.

Double-sided tape sticks the two faces together, so they can be filed to their final shapes together, so ensure they're exact mirror images of each other.








For the box section, I tried using the same aluminum, but when I put it in the metal brake to do the 90 degree folds, the aluminum just broke. It's not a very strong alloy of aluminum, it seems. So, these are some scrap 1/16" stainless steel pieces I had. Stainless is much tougher than aluminum, no matter what formula it is, and I wasn't looking forward to working with it.


Turns out, my little metal brake / shear / roller did have enough strength to fold the stainless. That was surprising.





Instead of one screw and one locating stud on the back of my brackets, I tapped the locator hole for the closest bolt size I had. I think it was 3/8". 


Bracket parts ready to assemble.

A woven nylon wheel was used to smooth out the aluminum parts before buffing.

Then a cotton wheel with some jeweler's rouge polishing compound to get the final finish.

I like the finished look of acorn nuts, especially when they're polished stainless. However these nuts, in stainless, were priced at $3 each! Soooo, nickel plated brass will have to do (¢47 each).


Test fit of my brackets, with the cargo net rolled up into place. I made sure to cut the hooks a little more generously than the factory piece, because IMO, it's always been way too hard to get the rod hooked in there. My new ones are easier to get in.

Now, to measure out the 36" strut. This stuff is just ordinary "pot metal" aluminum you can get form any hardware store. It's 2" extruded "L" at 1/8" thick. It won't be offering any stiffness to the chassis. Its only job is to look okay and hold a GoPro camera now and then. That block with the holes is a 123 block. They're steel blocks 1" wide by 2" tall by 3" long, and are useful for being heavy, clamping things, and for being perfectly square at all angles.

Abrasive disk to cut the ALU. It makes a terrible racket.

Measuring the angle of the bracket, relative to horizontal (more or less).

This line was erased and re-done to match the angle. Measure twice, cut once and all that.

A thin, fine-toothed blade on a bandsaw makes easy work of metals and plastic. Not so much for wood.

That top section will be folded down to match the angle of that bottom bit.

Filing and sanding the cutaway area for a cleaner seam, once the metal is folded. The sandpaper has a bit of duct tape on it, because I was expecting it to get repeatedly shoe-shined back and forth in the crack of that angle and it would have gotten torn up otherwise.

Bar in vise, and a piece of 2x4 as intermediary between the subject matter and persuasion from a large hammer. I didn't try the metal brake on the aluminum, since it's low-grade ALU and I expect it would have just broken. The vise-and-hammer technique doesn't force the metal to bend all along a narrow line, and lets it bend where it wants to, so is less prone to breaking.


Persuaded.

Masking tape to keep the vise from chewing up the metal.

Small brackets were made to reinforce the folded seam. This was probably pointless, but it looks better this way.





Test fit of completed bar. Photo was taken from inside the hatch area. Front seats are on the other side of the B pillar, there.


Another piece of stainless strap to make the bracket that mounts the camera to the bar.



I like the look of the drilled-for-weight, 1970's look. So 1" holes will be drilled all along the bar.

This thing is really useful for equally spacing things, accordion-style.

Pilot holes.

A step drill made the larger holes. The desired step was marked with a Sharpie to avoid mistakes. Fun fact: WD-40 removes Sharpie ink from almost anything, and cutting these holes required frequent spritzes with WD-40 due to friction and heat.



A second round of buffing was needed, to get rid of a bunch of scratches inflicted during the drilling.

Final install.

That.... actually came out kind of nice. And in any case, it's non-destructive, so a couple of minutes with a screwdriver and allen wrench reverses the entire thing to factory if I get sick of it. And no, my head does not bonk into it.

Believe it or not, this thing  does not obstruct the rear view mirror. I kind of feared it would, but nope.


View from outside the car, through dusty windshield.

Now, to wait for spring. Thanks for reading!