Building - Brackets

With the model in Fusion I printed out 4 patterns. I laminated 3 pieces of plywood together for each of the 4 brackets.

Since the brackets are longer than a single sheet of paper I had to print out 8 templates and glue them together. 4 of each end, both including the middle.

Each template with the plywood it'll be attached to.

This was a really messy process, the glue comes out everywhere when it gets clamped. I had to put in nails at each end to make sure everything stayed lined up.

I used a gluestick to attach the templates.

Everything drilled out.

Since the brackets are over 9 mm thick and the bearings are 7 mm thick I drilled 3 different sizes of holes. The third hole is much smaller and it only allows the drive axle through with a little bit of room to spare.

Since the templates were glued together, not everything was completely straight. I put some extra steel rod through each hole, putting the bearings in place so everything would stay lined up. As you can see the edges don't line up at all.

Then I used a belt grinder to sand everything flat.

Even after sanding them they weren't all the same I matched them up as best as possible.

Then I painted them black and gave them a matte clear coat like the rest of the wood.

Here are brackets assembled (but not glued yet). I used some extra pieces of rod in place of the drive axles just for the test fit. Everything seemed to line up ok at this point.

Since the axles at the end weren't quite long enough I added some small caps. I painted these black as well.

This wasn't planned but it ended up looking ok anyway.

Comments

Designing - The Cells

A distinction I should make before going any further is the difference between solar cells and solar panels. When I am talking about the solar cells I am talking about the individual square parts inside of the panel. The panel being the housing for the cells, some sort of stiff material for the back and a sheet of glass over the front. The cells produce power and the panel houses and protects the fragile cells. The first step of designing the solar panels was to get the actual solar cells I'd be using since literally, everything was dependent on their size. I was able to find some panels for fairly cheap on eBay, so I officially began the project with the purchase of 10 A Grade 4.8W 19.6% 156mm Mono Silicon Cells. Here's what that means: A Grade - Panels are completely intact. B, C, or D Grade will have increasingly large chips missing from the cells. Read more here. 4.8W - This is the power output. 19.6% - This is the claimed efficiency of the cells. ...

Update - Drive System

Right, so my suspicions about the bond between the drive arm and drive arm were correct. When I tried to extend the panels using a pair of pliers the epoxy joints cracked and the axle broke loose. The panels did not extend at all. I've drilled a hole through the drive arm and axle, I epoxied a nail into the hole and it seems to be holding. I can now extend the panel with pliers. It takes quite a bit of force to do it. I kinda doubt a servo will be able to handle it.

Building - Arms Pt. 1

Building the arms was by far the most time-consuming task. If only I had a cnc.... The rim of wood around the bearing was needed but I didn't like the really thick arm, I drew this up in Fusion, printed out the drawing, and stuck it down with a glue stick. The slot in the middle was an idea to make the arms lighter and look cooler. I tried it with one arm and then ditched the idea, it really didn't work and was a lot of work. All cut-out, at this point I didn't have access to a scroll saw so this was all done with a regular handsaw and files. It's pretty rough but I cleaned it up as best I could. Already looking much better. The next step was mass production, I needed 20 arms total. For this, I bought a used Craftsman Scroll saw. It was very, very useful. All cut and drilled out. Removing the paper was annoying, I used the top edge of a file to scrape it off. Since I put it on with a glue stick it wasn't very difficult to scrap...

Martens Solar

Search This Blog