More about Legs

Last night I completed the initial stage of the 2nd leg, enough so that I can start working on the shoulders and begin reinforcing them later this month before I put the top on and skin them. They are far from complete, but I'm learning a lot on this part of the project, and really getting into my groove. Since these parts will never really be seen again after I put the top on them, I'm wanting to take the time to discuss them fully, and document what I did. This is not only for others that may stumble upon my blog about the build, but also for myself when I go to do build #2.

The pipe I used in the main leg structure is a 1/2" CPVC plumbing pipe. I chose this because of price, availability, dimension and weight. The CPVC was easy to cut, very durable, and stays in place. I used a 5/8" boring bit to cut the holes in the leg struts, after measuring 1/2 way up and across from a set corner. What I did was mark each piece on the order onto the pipe and which was was up, so the holes were more in a straight line than the first leg. On the first leg I had a lot more cleanup once the struts were attached before the LLC pieces would weld.

I doubt I'd go the CPVC direction a 2nd time, as the pipe tends to have a bend in it. It's strong, and very lightweight, and having a little give to it helped with any light mistakes on the struts, but the tendancy to have the bend in it made it very frustrating to get put on. What I ended up doing to get it to lay flat in the tray was to put 7 1/2 lb weights across the leg structure to keep it flat. That also introduced an issue of the struts not keeping perfectly square to the LLC portions. if I had to do this again I'd attach the LLC and then the struts so I could put 90's on to keep the struts straight while weight was on them.

The part I like the most are the reinforcements I put up at the top of the pipe near the shoulder. This is the one section I had been contemplating since I first saw the leg designs last fall, and I like how this came together. One of the big things that Dave E puts in the plans is that reinforce near the shoulder where the major part of the stress will be found. By adding the extra strut right near the top, and welding it to the shoulder supports, I should be sharing the weight (and associated stress) onto the leg itself, and allow the entire superstructure to take the stress instead of just that one shoulder support. Time will only tell if I'm right or if I'm going to be re-building/repairing these, though.

Getting a "Leg" up

This week has been dedicated to getting the legs built.  I spent a lot of time working on the parts this week, and with the tools I mentioned in my last post, things have been moving a lot easier.  The one thing that I was concerned about, though, was the support beams in the leg.  The plans call to reinforce the legs, but I thought they could use something different than just a few reinforcement strips.  What I did was add another brace for the leg tube, that was joined the top segment of the leg.  This way the stress that would normally be isolated to where the leg meets the shoulders should be shared with the leg tube, and balanced through the whole leg.  Time will tell if this improvement helps or not.  At this point I need to work on the 1mm parts and place the top onto the leg to finish this first one up.

Close up of the Reinforcments

More shots of my  modifications

The nearly completed Leg

The bottom of the leg

Side shot

Leg with the top on (but not attached)

The way things look right now, I should get the 2nd leg to the point where the top is ready to be put on by next weekend.  My personal goal is to have the legs and shoulders done by the end of April, and if I can keep this kind of pace I think it's doable.

This week also marked the first time that I ordered resin detail parts.  I have an email out to JediKeith to see about getting the resin details for the dome in the near-ish future.  I also am getting in on a run for the power distribution panel.  Before long I'll need to order the dome drive, and drive motors.

Things are definitely getting exciting!

Post-MegaCon update

It's a twap frame!

It's been a week since MegaCon, and I've managed to get more than a fair amount done on R4.  The frame is now to the "stabilize and prep for skins" point, and the bearing is ready to be mounted once I'm ready.  And I finally started on legs!  I have 1 leg almost completely cut out (I just need to buy some 1mm styrene before I can cut out the last bits) and I'm to the stage of welding.  I've been learning more about techniques and how to actually get the most out of the parts that I have, and it's really helped.

Tools:  I ended up picking up a metal square, it's making a drastic difference on how accurate I can make cuts, even versus other metal rulers I have.  I also picked up a sanding block (instead of just using the paper for my mouse sander) and it's made evening out the rough spots a lot easier.  Lastly, I got a "bastard" file, which is making cleaning up uneven spots a LOT easier.  Thanks Todd for the suggestions, they have really helped!

Techniques:  You would figure after spending 6 months working with the knife that I would have figured it out by now, right?  Nope.  I have been holding the blade at WAY too shallow of an angle, and it makes the cuts take FOREVER.  After fiddling around a little bit this week, I'm at more of a 45 degree angle now, and it's making a massive difference in the quality and effectiveness of each cut.  It may sound like a small thing, but stuff like this definitely makes me feel good when I figure it out.

Other materials:  I ended up getting a new 4' table (the parts in this last update are sitting on this table now.  What I'm using it for currently is to hold parts while I work on other sections, as my workspace is limited.  It's also small enough that eventually I can bring it inside if needed as well.

The start of the 1st leg!

I'm planning on going slightly off plans for my legs, mostly in the support area.  I have the top section welded, and I'm moving forward.  Finding the pipe for the main housing was a little bit of a challenge, but I think my father-in-law has some 3/4" outside diameter pipe that will end up working nicely. I'll post up more leg shots once I have more to show.