Adding hinges to anything on Artoo is tricky, with so many curves and often located in tight spaces it’s really hard to get things just right. I’d bought a bunch of the Robart “350” bomber door hinges a long time ago, and successfully added some to the power charging panel. They’re not cheap, but if you shop around you can find them for around $7 a pair.
There are other options that are cheaper, like the McMaster Carr steal hinges or the plastic one’s Calvin found for 30c. But the consensus seems to be that the Robart hinges are the way to go.
Some builders have had to reverse and trim part of the hinge to get them to work, but I’m not convinced it’s necessary for the dome pie panels. Here’s Keith’s explanation on how he uses them.
Most people seem to use epoxy to secure the hinges, but I also like how Calvin uses nuts and bolts for easy removal.
For my experiments I temporarily used adhesive foam tape, and played with several configurations.
I started off with Keith’s method of trimming and doubling up the hinges. I also added back the cut out from the inner dome to the pie panel to give it more weight and substance.
I found that by reversing and trimming the hinge, it has to sit right on the edge of the dome cut out – making it really easy to align – this is probably the only advantage I can see for flipping the mounting.
But I’m not crazy about how it look so close to the edge.
I also had to slightly file the inside bottom edge of the pie panel to get it to open cleanly.
For my next test I went the minimalistic route, and used a single hinge, configured the ‘correct’ way with it extending further into the dome. I also did not attach the extra cut out to the pie panel.
It was a snap to align and worked surprisingly well and opened just as easy as the first, if not easier. I suspect a servo would like the setup a bit better, being lighter and only having to move one joint. However, it felt more flimsy (obviously) and it would be super important to keep the single screw tight – which is hard to do on anything Artoo.
In summary – I like the heavy feel of the first option and how it sounds when it closes, but I also like the simplicity and cost saving of the second. I’m going to sleep on it tonite and get a second opinion tomorrow before permanently affixing anything to the dome.