Playing Ketchup Episode III: Paint the Town White

During all the work I was doing on finalizing the skins for paint, I was actually painting the legs and feet. Once I had the skins ready to go I taped off the Inner Skins and painted them as well. It was a time consuming experience, and my perfectionist ideals didn't help. But I tried to chalk any chips or dings up to natural weathering.

One of the first roadblocks I came to during assembly was screwing the Center Ankle Cylinders to the Center Ankle. I apparently never tried to dry fit these before paint or I would have seen the issue. Its such a tight fit inside the ankle that its pretty much impossible to use a normal screw. After a few different attempts from advise on the forums, I came up with what worked best for me and my fingers. I used set screws placed into the cylinders first, and then screwed a nut onto the backside with a ratcheting wrench. It still wasn't easy, but I got there in the end.

Some of the easier portions of building came after. I sanded and cleaned up my foot strips and the feet area they cover before using a strong epoxy to adhere them in place.

I also painted my homemade Utility Arm bay back cover and screwed it on along with the Utility Arms and Large Data Port.

My R2 isn't based on any one particular movie, but the bits and pieces I like from each. One of those bits is the silver strip on the legs that matches the indent in the Rocket Booster Covers. My JAG version of the legs don't have this stripe CNC'd out like some other versions. I knew masking it off during painting was an option, but I was afraid that any chipping later would annoy the hell out of me. I happened to find some silver pinstripe tape in the auto department at Walmart. It's close enough to the exact size I needed that I went ahead and gave it a try. I placed the covers on the legs, marked them with a pencil and made a line all the way around with a ruler to help guide for a straight wrap around the legs. I overlapped the tape at a point where it would be underneath the covers. I'm really pleased with the result. You have to get very close to tell its pinstripe tape, and later weathering will help camouflage it even more.

I used VHB tale to adhere the skins together. It worked fairly well, but I did use some super glue in a few areas that the tape just didn't seem to work. It helped to close the gaps. I'm not sure if its because my VHB tape was a couple years old, but it did have several places that didn't adhere very well.

I'd recommend a whole lot of clamps for this too. I didn't manage to take any pics of my skins during the process, but its almost comical how many binder clips and various sized clamps I used. 

Next came getting all the various detail pieces attached to the skins. I ran into some issues with the Pocket Vents. Mine have wing tabs that are meant to help you attach them to the skins with tension alone. Problem was that they needed some heavy bending and filing to get them to fit into place. Because of my homemade Kick Panels I ended up using a dremel to put a pretty good curve into the on of the top tabs on each Pocket Vent. Just another unforeseen step in the assembly process.

I got far enough along in the assembly process to put the magnets on the back door. Clamping the door in place, I marked the inside and then used epoxy to adhere the magnets in place. Those things aren't called "Strong Earth Magnets" for nothing. It really sucks the door into place when you get it barely in position. Problem is the magnets are stronger than the epoxy and I've already had to re-adhere a few into place after they stayed on the frame magnets. I will probably have to end up using my stronger 3500 psi Gorilla Epoxy in the end.

Playing Ketchup Episode II: Like a Rolling Stone

I broke all the various body pieces apart in late November. I sanded the steel feet back down since the primer was heavily marred and had sharpie marks all over them. Then I bought a few packs of drop cloths that I was able to fashion a paint booth from by hanging them up in the garage. It did a pretty good job of keeping overspray off everything, and there was a lot.

I was able to get most everything primed before going on a week long cruise at the beginning of December. Then I commenced painting over a couple weeks after I returned. I had a lofty goal of getting everything painted and assembled before the end of the year. I didn't make it, but was not far off.

I still had to do a few things to the skins though. In between coats of paint on the legs and feet I fabricated a backer to the Utility Arm bay and some Kicker Panels for the bottom of the sides where the skins meet. These were both pretty easy to make with some aluminum sheeting and various things found at Lowe's. 

I initially tried to drill and tap the frame to attach the Utility Arm bay cover. After breaking one tap and a second drill bit that failed miserably, I decided on another route and epoxied some gutter flashing to a piece of aluminum that I cut and rolled to the correct size. The sheeting wraps around the frame and uses pre-drilled holes. Viola.

The Kicker Panels were made of the same aluminum sheeting cut to size and bent at a 90 degree angle in case anyone wants to get down and look up into the space they cap off. I found some steel panels and L-brackets at Lowe's. I combined them with some captive studs, epoxied it all together and came up with some very solid kick panels. They screw into the four holes that were already on each side of the Com-8 B frame. They don't budge at all and cost probably less than $10 a piece.

Next I needed to do a little work on the skins before painting them. For some reason the John Sherrell skins had never been updated. Can't imagine why /sarcasm. So you have to cut out the square that the Power Couplers go behind. A little measuring, marking and elbow grease with a dremel and file made fairly short work of the issue.

I needed to do the same thing for the back door panel, but was finally faced with the problem I made for myself awhile back. I had used shears to cut the back door out of the inner skins. The Inner Skin portion of the back door got pretty bent up in the process. Hindsight is always 20/20. I had bent it all back into place, but was never truly satisfied with how things came out. I even bought a second pair of skins just to fix the problem. But, I kept thinking about it, not wanting to use the extra skins unless it was a last resort.

Then I had what I think is a pretty good idea, including something that could be implemented into future skins. Lowe's sells a sheet of aluminum that is only a 1/4 inch wider than the back door. I picked one up and spent some time rolling it by hand, fitting it to the frame and rolling some more till I felt it was sufficiently matching the shape of R2's frame. Then I trimmed off the extra 1/4 inch and had a perfectly sized and rolled solid back door. After placing the outer skin portion over the new inner skin I marked the areas that needed to be cut out for the back Power Coupler and Coin Returns. Here's where I did something a little different. Instead of cutting out the entire rectangle of the coin returns, I only cut the area that protrudes into the skin. This way I'll have a much larger area to adhere the returns to the back door panel. I'm really satisfied with my solution to my own problem. It had upset me for some time, but in the end its a nice clean door, maybe even better than the original.

Finally I decided to use captive studs on the Power Couplers and Octagon Ports. So I drilled the appropriate holes in the Inner Skins for each piece. Having done this, I'm not sure I would do it again, especially on the Octagon Ports. They are engineered so that its extremely hard to get a wrench around the nut that holds them in place, and I even abandoned it on the bottom two screws. This also causes a big problem if you can't get them to suck into the skins. When you go to adhere the Outer and Inner skins together the studs will create gaps in the skins where you can't get them counter sunk. I will say I didn't have near as big an issue with the Power couplers. Things to remember for next time.

Playing Ketchup Episode I: Stinkin' Feet

Its been four months since I've posted any updates to my R2 build - mainly because I've been concentrating on actual building while letting the posts slide. But today its a balmy 20º, snowing and I'm taking a day off work after a nearly 90 hour work week. So get ready for a couple long posts of progress.

I'll start where the last post left off - getting the NPC motors finalized for installation. I ran into the same problem everyone did with the old battery boxes and had to grind the tops of the NPC motors in order for them to fit inside the boxes. I also had to modify the openings of the left box a fair amount to get it to slip all the way over the motor. Not sure why the right one didn't require it, but I'm fine with only cutting one box if the other one works.

At this point I was done with the NPCs but needed to do more work on the Battery Boxes. I wanted to make sure the Battery Harnesses were going to be secure, so I drilled a hole into the harnesses and the boxes at the bottom of the main vertical piece, where the decorative cover would eventually cover the unsightly screw. I had to do a bit of sanding on the harnesses to get them to fit in the box facade as well. My boxes are from an older run before the face of the box was CNC'd. So they are not quite exact, and you can tell just by looking at them. Eventually I'd like to replace them with the newer improved version.

At this point I was looking at the issues of securing the boxes to the feet. The curved inside panel of the feet have holes for a screw to slide into as you can see in the pic below, but after a lot of staring I realized the boxes were such a tight fit that I'd never be able to get box mounted screws to slide down in the pre-drilled foot holes. I did a little searching on the forums, and decided to drill two holes at the bottom of each box and foot that a screw could pass through and be tightened from the bottom. Drilling into several hundred dollar parts is always scary and this was no exception, especially because of the curved area where each hole needed to be.

Its a tight squeeze with the fingers, but it works quite well. In the end it turned out very good, and the boxes are rock solid on the feet.

The final piece to the feet puzzle was drilling out the holes for the Knurled Hose Fittings. After even more research I went to Harbor Freight and bought a step down drill bit. It was money well spent and made expanding the pre-drilled holes quite easy. Going from 1/4 inch to 11/16th took only a few minutes on each hole and the KNFs slid right into place.

At this point its was nearing late November and I was ready to break everything down for paint. Luckily it was an unusually warm December, and the added help of a propane heater didn't hurt either.

I'm just talkin' bout Shaft

Work commenced again yesterday towards final assembly. The NPC motors come with a shaft on both sides, one of which needs to be cut off to allow the Battery Boxes to fit over them. I failed to take a good pic of the motors with the extended shafts still on the droid, but they can be seen here with the motors attached to the JAG foot drives:

At first I tried cutting the shafts with a metal blade on a chop/miter saw. It cut fine but was only able to get close enough to end up leaving about a half inch of the shaft still on the motor. It also made the shaft extremely hot, which probably wouldn't damage the motor, but I didn't want to take that chance again. Since something else was needed to finish the job I decided to just use a hacksaw. With it, there was no problem getting extremely close to the shaft housing. It only took a few minutes to trim off the remainder of the shaft, then a couple metal files were used to clean up and smooth out the finished product.

The same process was repeated on the other motor shaft, minus the chop saw. Fairly quick and easy. Definitely easier with two people so that one can hold the motor while the other saws. Now onto getting the Battery Boxes to fit. That requires grinding the tops of the motors, and a cut or two to each box as well.

Must be Italian.

I finally re-kickstarted my build a couple months ago after about a year hiatus of working on R2 and staying off the astromech boards. One of the first things I did was buy a new/second dome. I knew my 300mm dome was going to cause me some headache down the road, even after all the hours of work I spent painting and sanding. Now that I'm further down that journey I decided to ditch the old dome and get one of the new Hydro formed domes. These are made out of a different aluminum with a completely different forming process, hopefully eliminating most of the issues with the older style domes. They also have almost everything pre-lasercut. Mine came in a few weeks ago, but I was in the middle of getting all my electronics up and running that I never posted pics. So here you go.

I also splurged and got the new Ultimate Hinges for 11 of the dome panels. A new electronics portion of this solution is coming soon. Its hard not to want all the bells and whistles of R2, even when yours isn't quite "finished".

One small roll...

Here's a video of R2 rolling for the first time after over a week of wiring, crimping and cutting. Long, long time in the making.

Holy sheets!

A few other things needed to be done before I could get Artoo up and running. I needed to decide how to run wires through the legs, and I needed to fix the center ankle locks.

After even more debate (sometime I swear I spend hours just looking at something before breaking down and doing it), I decided to drill holes in the underside of the ankles. Most builders do this, there's only a few that have wires routed differently and hidden all together. I figure they are so low to the ground, someone would have to get on all fours to see the wires come out the ankles. This was pretty easy, just measure and mark the spot on the ankles, and use a drill press to get a nice smooth hole. Later I took a small file and sandpaper to de-bur any slag. I also put a teeny tiny angle on the inside wall of the holes. That way there is less of a sharp edge to wear down the protective wrap of the wires and it should help prevent any shorting down the road.

Always a little stressing drilling or cutting into something very expensive. I'll probably drill a hole into the battery boxes when I get further along. A lot of builders drill the second hole into the top of the foot right below the ankle. Neither is better than the other, its all personal preference. I figure the battery boxes cost a lot less to replace if I screw it up.

Back when I installed the center ankle locks I noticed there was a bit of a gap left below the locks themselves. This caused a tiny bit of rocking in the center ankle when changing direction. So I knew I had to fix it. I had some aluminum sheeting laying around that I plan on using for the kick plates and behind the utility arms. Test fitting the sheeting looked like it would be just the right thickness. I took the locks off, laid them on the sheeting, drew a line where I needed to cut and broke out some cutting shears. I bent them back out as straight as I could and then used some fast setting epoxy to adhere them to the locks. A little sandpaper and elbow grease evened out the transition between them. I slapped them back on the center ankle and viola, a stable ankle that no longer rocks.