Machined Greeblies

[jeanluc83]

I’m planning on machining all of the greeblies for my R2. 3D printed details are okay but machined aluminum parts are so much nicer. All of the machining will be done manually so some of the details will be challenging but should be fun. First up is the shoulder buttons since they are the simplest.

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I started with a piece of 1” diameter 6061 aluminum. The profile was turned in the lathe. I then rough cut it to length using a band saw and faced the back. The center hole was tapped 8-32 for mounting.

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The two holes near the outer edge were a little tricky. I don’t have a vertical milling machine and hand layout is not nearly accurate enough for this so I had to get creative. I ended up making a 3D printed drill fixture. The two metal parts are drill bushings made out of bolt cutoffs from the scrap bin. They were pressed into the fixture to keep the drill from eating up the plastic. The setup worked surprisingly well.

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Overall I’m really happy with the way the buttons came out.

[jeanluc83]

A couple of close-ups.

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Next up will be the shoulder hydraulics. They are also pretty simple but there are a couple of the details that may be a little challenging to reproduce.

[Marc ph]

Those are amazing

[jeanluc83]

Those are amazing

Thanks!

I've started tooling up for the shoulder cylinders. I don't have a straight knurling tool so I'm making the knurls using my lathe like a shaper. A tool bit was ground to 90 degrees which is fed longitudinally using the lathe carriage advancing the tool bit until final depth. The spacing of the knurls was set using evenly spaced marks around the chuck and a pointer. The knurls on the test piece turned out good but the process is a bit slow. I'm sure it will be a bit faster once I get into a rhythm.

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[AFR0J3D1]

Be careful you might be the greeblies guy before long. These look very cool.

[jeanluc83]

Be careful you might be the greeblies guy before long. These look very cool.

That is not a bad idea but I’m only making a set for my own use, at least for right now. I may make some more in the future to offset the price of the parts I can’t make but I don’t think I could ever compete with CNC machined parts runs.

[AFR0J3D1]

well, we are here for the ride keep up the good work.

[jeanluc83]

I'm making progress but I'm down to 2. I've made some stupid mistakes but it happens. I'll get there in the end.

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[jeanluc83]

More progress. I'm really happy with how these are turning out.

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[jeanluc83]

The shoulder hydraulics are nearly done. It took me a bit longer than expected but I'm happy with the result. All that is left is to sand out the milling marks and drill and tap the mounting holes.

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