Okay, I promise this will be the last KHF post for a while. I bought a bunch of plugs from Ace and tried them out tonight and I think I’ve found a keeper.

It’s a small nylon plug that normally leafs out when a nail is pushed through, but I removed the nail and tapped the hole for a bolt.

I’m pretty sure it’ll hold for now, but would pull out if I gave it a really good tug. The good thing about this plug is that the expansion happens at the top in side the aluminum KHF holding it snug.

I also tried a small metal wall plug, but it didn’t work so well and deformed when expanded in such a tight space in the tube. I’d probably have to replace it every time I took the hoses off, it also didn’t grip the hose so well as the nylon one.

More re-assembling tonight after painting last week. I did a mix of things from the feet to working on some skin panels.

I got the feet and ankles back together, and using the hex bolts worked out great. It was a breeze installing the ankle details.

With everything R2, there’s always a few steps back with a dozen forward. Today it was the braided hoses. I’d planned on using these expanding rubber plugs to hold the cables in place, but they didn’t quite work as I’d hoped. For some reason rather than bunching up and expanding the nut inside just moved/ripped up the rubber with minimum expansion as shown. The ‘bulge’ at the top being the maximum width.

Back to the drawing board and Ace Hardware tomorrow to look for an alternative. I was tempted to try Douglas Olson’s KHF System again, but space is very tight and they’ll not work for me with the JAG feet and drive system.

The other problem I had was once I tried to install the battery boxes they wouldn’t fit over the NPC motors. All the test fittings I did while filing down the tops of the motors was done without the ankle on the foot, so now I have less room to bend the box over and down onto the motors. An easy fix, but I was hoping to get the feet, ankles and legs back together tonight and now I can’t.

I also worked a little bit more on the frame and got the front vents installed and attached to the frame at last. Not sure how I’m going to fix in the blue surround at this point. Maybe silicon, but I want to be able to remove it easily with the skins. The fit is tight and I can see when removing the skins that it may get pulled off with little effort.

I’d posted a few weeks ago that I had a problem with the bolts on the Knurled Hose Fittings (KHF) hitting the drive wheel in the foot. Well I finally got around to cutting down the nuts and at the same time making some small nuts for the battery boxes.

For the feet I simply cut the nuts in half and filed them down. Here’s a before and after shot

At first I tried to cut the nuts with a hand saw, but it was slow going so I switched to the dremel

Here they are attached to the foot with the expandable rubber plugs which hold the hose in place

I also had to adjust the holes in the feet to get the foot strip to line up properly. I just used a hand file to remove some material

For the battery boxes I had to grind down the nuts to fit into the tight space.

Nice and snug fit

[edit 12-03-07 – see the following post about the failed rubber plugs on the KHF)

Weather has turned a little cold and we’ve had some rain, so I got to work in the garage this last weekend.

It was a mix bag, from cleaning up space to work to jumping between painting some parts, cutting the skins and fitting the battery boxes and hoses. I also tried to troubleshoot some issues I’m having, like the dome speed rotation, but more of that later.

First up I really needed to make space to totally disassembled R2. I’d been dreading it and a few events throughout the summer kinda gave me an excuse to avoid it. Even though he’s not finished it’s still been fun driving him around and people love him.

So I started off by breaking him down and inspected parts for wear, missing screws etc.

I never did get a coat of undercoat on the center foot before C4, and some surface rust had set in. I was also surprised how well the omniball castor’s have held up given the terrain I’ve run him over.

A once over with some sandpaper removed the rust from all the center foot parts and I was able to give them a coat paint.

I also inspected my center ankle for any problems. George Luck broke a JAG center ankle right after C4 and I was a little worried about mine, but all the joints looked fine. I’ve heard of two ankles breaking now, and both times the droids had done a long cross country trek for C4. I’m wondering if that’s the problem rather than every day wear and tear. To be on the safe side I had ordered a spare center ankle from Jerry just in case, but hopefully I’ll not need to use it anytime soon 🙂

Next up, I finally drilled the holes in the outer feet for the Knurled Hose Fittings (KHF). I had a bit of trouble securing the the foot on my drill press, so had to use my cordless hand drill instead, problem was the drill bit would not fit. I had to use my stepping bit instead. I don’t think it like it much as the steel feet are pretty tough – but it got the job done.

The Kurled Hose Fittings only just arrived last week from Doug and they have a nice feature where the hose is easily secured with a screw-in plug.

With the KFL I also got some new braided hoses, but I wasn’t too keen on how gold they were. I much prefer the original copper one’s I got some time ago.

I had to insert some tubing into the braided hoses to make sure they held their shape and secure the hose in place inside the KHF.

Now comes the kicker with the KHF – there’s always a kicker right? They hit the main drive wheel once I got things back together

I even switched out to using regular nuts, but it looks like I’ll need to trim the KHF’s down by half

I decided to move on to cutting the back of the battery boxes to accommodated the big NPC motors. I couldn’t find a template anywhere, so it was a bit of trial and error. I started off with cutting the smallest hole I could, traced from the matching hole in the foot. It wasn’t big enough to slide down and over the motor so I gradually made things bigger until thinks worked. Once the box is in place you’ll not be able to notice the hole.

I’ll try and create a PDF template later tonight to share [update – here’s the template]

I also had to grind down the motor in three spots. In the Dave Painter tutorial it looks like you only need to grind the top sides of the motor, but I also had to grind the bottom outside edge too

So here’s the first foot assembled with the motor encased in the battery box ready for painting. Next step battery harnesses.

As I said at the start of this blog entry, I did a lot more on R2 over the weekend, but I’ll stop here for now.

As always more photos in the gallery section.