Date: February 9, 2007
Total hours spent today: 7

Today had me running all over the shop attending to all kinds of stuff. It was an immensely productive day with a ton of little tasks attended to. Today is very picture intensive, as there was a lot of action happening today.

I'll start off by saying that I've been holding off on dealing with the skins because of the tool arms. You see, when I first put R2 together, I noticed that the two front tool arms did not properly deploy through the skins. For some reason, I decided in my head that this was due to two reasons: first the tool arms were the wrong size, second the skins were incorrectly mounted. Resin shrinks when it cures, and these tool arms were resin castings of to-spec aluminum arms. Though I've ordered and paid for a set of al tool arms, they have yet to arrive. (Not sure if you can smell the bitterness there, but it's there -ed) I've been checking my p.o. box anxiously for the past week, but they just don't seem to want to get here.

This has proven very frustrating, as the list of things to do outside of the main body has gotten very short. So things have slowed down. Well, yesterday I decided that I was no longer going to be a slave to those tool arms, and that I was going to push ahead. Granted, this type of maneuvering has bitten me in the butt in the past, but my time is precious to me, and I cannot just sit around wasting it.

So I prepped the tool arm assembly and installed it.

And then placed the skins over it to see how it fit.

As you can clearly see, there's a lot wrong in Muddsville. But what I learned most of all is that there is NO WAY that those tool arms are going to deploy properly through my skins. Unless I significantly rework them, they are garbage. So I committed to throwing them out. Even if I have to scratch build my own tool arms, it will be better than trying to work with those wonky, poorly cast, undersized tool arms. (bitterness again??? -ed) The good news is that from this, I felt comfortable in moving forward. No looking back.

The next thing to do was properly align the skins. I drew a center line down the main horizontal on the frame, and used that as a guildline to line up the edges of the skins. I also used the lips of large data port recess as a guide. Once the skins were in place, I used painters tape to secure them to the body. I would start at the center of the skin, and work my way out towards the edges. The skins are quite flexible, so you have to make sure they are flush all the way around before drilling any holes.

I was sort of pleased and releived to see that the skins did indeed sit differentlly than when I had first attached them, confirming that they were indeed out of alignmnent. Only ONE of the original screw holes was useable. Since I've already blogged about attaching the skins, I won't repeat it here, but I will talk about a couple facets of skinning that I did not talk about earlier.

For example, a killer tap and die set can only help! Here's a picture of the one in the shop. It's got so many sizes it makes my head spin.

And here's a little tip I actually picked up from my idiot father. If you ever need to make a screw shorter, but don't want to run to Home Depot, you can always cut it with a hack saw or snap it with a good pair of pliers. The trick is retaining the threads. If you saw it or snap it, you're going to have a tip that won't be threaded properly, and you can damage whatever it is that you're screwing into. (NICE! -ed). So the trick is, you screw a bolt onto the screw before cutting, then after you cut it, you unscrew it. That might sometimes take a pair of pliers and screw driver, but it will restore the threads to the way they were priot to cutting. Good trick! Thanks dad! I guess we were wrong when we said you were good for nothing!!

And here he is, all reskinned. There's like three screw holes at each junction now, which makes it look pretty ugly. However, since he will be painted, those will all go away in the final analysis. Also, all but one of my screw mounts held in place really well. The only one that failed was due to the fact that I drille right in the middle of the al and the pvc. So when I went to tap it, it just popped of. No big deal though.

With the skins looking pretty good and in their NEW position, it was time to revisit the mount I had made for the two primary grills. My original design had them fixed securely in place, and I knew that was going to be trouble. I put the mount in place, and found that it was indeed off center by a couple hundredths of an inch. This seemed like a good opportunity to make the mount solution more flexible and robust. The vents still fit well on the vertical, but needed to be shifted on the horizontal.

I got on the mill, and expanded the two slots on the horizontal by about a quarter of an inch.

Then went to the drill press and drilled a bunch of holes. I used a right angle bracket from a ruler to make sure the mount was standing at a good 90 degree angle.

Tapped all the holes, and screwed in a bunch of cap head screws. This will allow me to move the mounts to the left or right by about a quarter inch, and also to keep them very firmly in place.

And here's the final assembly, in place and ready to rock.

Before I took the skins off to do some more work, I put a bunch of the little pieces I've been working on in place, just to see what they looked like. Here is the torso with the power coupler, octagonal port, side vent, coin return, and primary vents in place. Lookin good, lil' buddy!

It was time to patch up some of those holes.

I put painters tape on the back side of the skin to stop the putty from just squirting or sliding away. Worked pretty good.

I was still pretty pumped about how well those magnets worked out on the access doors on the front of R2, so I decided to attach the plate that goes around the vents using the same methodology. Anything to avoid gluing it in place! So I fired up the super Maxim glue, and put four of those rare earth magnets into place. As you can see, I used clothes pins to keep the magnets in place, and to apply pressure to them.

And as the day was winding to a close, I thought it was time for a little back door action. Yup, you read that right, you perv. But I'm talking about the door that is located on the back side of R2. Wait, that didn't sound much better. Perhaps a photo.

This will be the main access way to R2's interior once the skins are attached, puttied, and painted. The bummer is that my skins did not come pre-cut for the back door, so I'm going to have to do it myself. And I've got to be careful about it, as a cut 1/4" in the wrong direction will render his back skin useless. So I took my T-Square and drew lines where I want to make cuts.

You cannot really see it here, but it's all marked up and ready for the dremel.

It was getting pretty late by this time, but I wanted to get one more thing done. The other day, I milled out some sheet aluminum that was going to be used to close off 2 openings on the body, just above where the foot battery packs sit. one task remaining on that job was to fabricate plates for that assembly which would go between the rectangles and the skins. Heck, I don't neven know if the real R2 has this, but I want them.

Whenver I make anything that ends up making contact with the skins, I use a plate off the frame to trace the contour of it. That means that the piece will fit pretty darn well inside the skin. I did that on to two pieces of scrap aluminum that I had left over from a previous op.

I then went to the band saw and VERY carefully cut along the line, just on the outside. The more you take your time here, the less work there is to do later. So I did this part very slowly. Turned out really nice.

I started to file the rough edges down by hand, but then realized I'd make much better progress if I put the stock into the vice. Good tip shown in this picture. Don't damage your piece by clamping it directly in. Use some MDF or other wood scraps as pinchers. Keeps your stock in good shape. Once in the vice, I went to town on it with a course file, and then a finer one to get a really smooth edge.

After they came out of the vice, a quick pass or two with the fine file to de-burr it, and I'm ready for the next step. Note that softening up and de-brurring that edge is really important. Especially when something comes off the mill. Those edges can be razor sharp. I've already cut myself a couple of times on freshly cut aluminum edges.

And that's it for today. I'm back in the shop tomorrow for some more back door action, so stay tuned!