Another quick post with old work, this time on how I attached the battery harnesses to the boxes.
If you’ve been reading any R2 blogs for any length of time you’ll notice that most builders love silicon. It’s a very versatile and used to attach all sorts of things on your droids.
I’ve found out the hard way that not all silicon is created equal. Victor highly recommends GE Silicon II, and I have to second that. I’ve tried the generic brands and found they sometimes do not dry as well, especially if it’s a used tube, and often it will not bond well to aluminum or pull away after a while. This could be my lack of experience, but I’ve yet to have a problem when I’ve used the GE product.
I don’t think you need much silicon to hold the battery harnesses in place. I decided to add some to the top and the back side of the top swivel bracket.
And then gooped inside the lower bracket
I then moved the around until I was happy with the position and clean up the excess silicon before it had time to set.
This is another retroactive post on something I worked on sometime ago.
I wanted avoid permanently attaching the side vents to the skins to allow more flexibility, but it’s not as easy as just making a simple bracket and screwing it to something like you could on a wooden frame.
I’d experimented with a few different methods but wasn’t happy with any of them, and I was convinced I’d end up using silicon to stick the vents to the skins permanently.
But at the last minute I gave this idea a shot – I tried attaching an aluminum plate to the back of the vents and hoped that a combination of sandwiching them between the opening in the skins and the pressure from the new aluminum plate from the inside would hold everything in place.
I took some of the same aluminum sheet I used for the side panels.
And cut squares that were slightly bigger than the vents and bent them to roughly the same curvature of the body.
This a shot of the new plate from the inside of the frame covering the side vent hole
I then used silicon to attach the plate to the backside of the vents
Then it was just a matter of waiting for the silicon to dry and wedging them between the skins.
Believe it or not I am still alive and working on Artoo. I’ve had an incredibly hectic couple of weeks, but I’ve still been able to fit in some building here and there. Unfortunately, I’ve not had time to blog the progress, the good news is I have been taking photos so hopefully I can go back and post what I’ve missed later. WonderCon is also coming up in two weeks and I’m rushing to get Artoo back together and presentable.
Most of the work this last week has been working on the electronics and finishing the skins, like attaching the small detail pieces, doors, panels etc. I’ve only got a few more bits to go and he’s looking really good.
The panels and inserts I simply attached with silicon. Nothing fancy, just held in place with tape while it dried over night.
Some people use epoxy to fix the rear panels just in case they decide to collect signatures, but I really don’t care for signatures (nor epoxy) and this is a much cleaner/quicker method for me at least.
I did get one door hinged, the one I’ll be using to access the on/off switch and charging port. Like a lot of builders, I had a lot trouble getting the Robart to work correctly. In the end I left the hinge in the default setup as suggested by the manufacturer, but ended up using some spacers to lift the hinge away from the skin/door slightly. I’ll try and take some better pictures and detail how I add hinges to the remaining doors.
To secure the door closed I attached a magnet and metal stop for it to hold on to.
I also added a small warning sign to the inside of the door. It’s my interpretation of the one seen in ROTJ where Artoo helps free Leia from the chains.
One of the issues I’ve had is that the back door doesn’t fit well. I’ve been avoiding it, but I would like to have it attached for WonderCon. The problem is the skins don’t quite wrap around the frame snuggly, which leaves the back opening wider than it should be and the door has more of a gap around it than I’d like. I’ve still going some tweaking but I think I may have to live with it for now.
This is the correct gap at the top of the door
I now need to remove the skirt and bottom ring to drill and tap some holes to attach the octagon ports and power couplers. Hopefully this will be the last time I have to disassemble the frame for a while.
I forgot to post this small update a few days ago. I’ve figured out most of the other skin detail parts and made brackets to attach them, but still needed to work on the coin slots. There’s a slight problem with the design of the frame and/or the latest run of coin slot strips. It’s slightly to long and bumps into one of the frame rings – and either it or the frame needed ‘adjusting’. They don’t call this building for nothing.
I opted to just cut a small slot in the frame ring as it seemed easier than cutting the strip. It also save two screw holes in the strip to allow me to use them to fix it to the frame.
I put on the skins loosely with the slot in place and marked from the inside where it touched the frame.
I then took my Dremel and cut out the slot
I cleaned it up with a small file to make the corners square and did a test fit
All that’s left is to make a small L bracket to secure it to the frame, but I’m also tempted to simply silicon it to the skins permanently.
I was going to add a few more coats of paint to the skins today, but on close inspection in the daylight they looked fine. A lot of the dust spots I was seeing yesterday just rubbed off with my finger now that the paint has had time to dry. I’m going to leave it a few more days before I attempt to remove the masking tape, as it’s been pretty cold and I’m not sure how the paint cures in this sort of weather.
I’ve decided to re-assembling R2. Started off with something easy – the center ankle as it’s relatively simple and self contained. I need to get him back on 3 legs to start laying out the electronics again. I’m probably going to move things around a bit, for example I know the speed controller can’t stay where I had it on the back mounting plate as it now hits the skins. It may end up on the back side of the plate or somewhere else internally. I also want to build in some sort of switch and circuit to allow me to charge the batteries in place rather than having to remove the cables each time to clip the charger on.
I’ve been paranoid all week that I’m going to ding or mark the paint, and tonight I had to moved passed that. Right off the bat there was no avoiding dirty fingerprint from the grease when handling the new white paint, plus I scratched a some paint off trying to get the ankle to fit back in the foot shell slot. I really should have filed down the metal parts a long time ago to compensate for the added paint – but I didn’t. I’m sure it going to wear off in this spot anyway, but don’t ya hate it when something like this happens?
I’m glad now that I didn’t get things powder-coated and at least I can touch it things up myself if I need to.
I’m going to have to keep an eye on the foot shells as they’re steel and prone to rust, especially where I live on the coast. It’s ironic that one of the reasons I went with an aluminum droid was because wood warps so easily here, even when sealed, and now here I am worrying about rust from the salt air. I may just grease up this area when I get around to weathering him.
I also noticed that nearly all of my ankle cylinders are scratched up and should really be repainted, but I’m not going to do it this time around.
I used silicon to attach the foot strips to the foot shell. I should probably tap and screw them on, but I’m feeling lazy and really want to see this done. I roughed up the two surfaces and taped on the strip. I’ll probably know tomorrow if it works.
I think it looks pretty cool all put together don’t you think?
One last thing while I remember, don’t forget to use screw Loctite or something similar. I missed a few screws in the feet before C4 and lost nearly all of them by the end of the week.
Posted by Chris on November 30th, 2007 in Feet, Finish/Paint, General, Legs | No Comments
Tags: ankles, Feet, foot strips, loctite, re-assemble, rust, scratches, silicon, weathering