Friday, June 12, 2009

The Frame Goes Up

Now that I had the frame pieces all cut up, I needed to get some Weld-on 3. Like I said before, I bought Weld-on 16 by mistake. 16 is thicker and Dave said to get 3 instead. So I drove 15 miles to buy it at Gavrieli. Turns out they don't carry 3 anymore, only Weld-on 4 which seems to have replaced it. I learned later that there is also a Weld-on 4807 specifically for styrene, but since Dave never mentioned it I'm gluing my styrene with Weld-on 4. 3, 4 and 16 are all for acrylic. But they seem to work fine on styrene.

Reading the label for Weld-on 4 made me think I inadvertedly purchased radioactive materials. I kept expecting to read "Not for use by humans. Do not look directly at liquid. Not intended for sale in inhabited planets". The lid cap also refused to twist open. The Hulk would have turned purple trying to open it. When that finally opened, there was yet another cap inside with the words "Cut open" on it. Might as well have been a smiley face with it's tongue sticking out. I pryed it open and poured it into the overpriced applicator bottle.

I was ready to start. I unfolded the folding table in the kitchen under my wife's angry eyes. I bribed my wife with a trip to the hair salon so I could work without vibes and once she left I lay the foundation.

I started with the Base Plate #1, alignments facing up. I drilled the centre holes in 3mm (for those of us who don't live in communist countries that's about 1/8") with my Skil cordless drill. Did not use a drill press because I'm actually pretty good at drilling at 90 degrees and because wife has not given the budget a greenlight. I purchased a drill press stand from Sears, which claimed to convert a standard drill into a press. BIG mistake. It only takes certain drills, mostly Craftsman drills and nearly ruined my Skil drill. It damaged the drill enough that I might need a new one in a couple months.

Anyway, I cut off the edges from the base plate and saved them. They go here:
That's the ANKLE INSET PLATE. You'll have two of those.

Now comes the real heart of frame building: gluing in those uprights! Every time I saw this done on other people's frames I thought "These people must be cheating" because whenever you cut an upright, there's an edge that isn't entirely flush. This is because to cut the styrene, you go over the line once very softly, cutting only the paper template, and then again several times only a tad harsher each time. In the end you pull the piece up towards the cut and fold it in the other direction causing it to snap. This is fine in the .040" styrene (1mm for the comrades behind the iron curtain), but in the .125" styrene (3mm for the happy workers of the People's Republics around the globe) this will often cause very mild flashing. Unnoticeable to the eye, but obvious when you try to make the piece stand on its side.
Thankfully, the Weld-on thing really works. Here is the first of the LOWEST UPRIGHTS going up in its alignment.

You'll notice the two set squares (triangles actually but I guess that it was broken in two after it was invented) are covered in Glad ClingWrap. This is because Dave mentioned having to occasionally pry his squares from his styrene due to the Weld-on actually melting the styrene. Well, the only thing that sticks to ClingWrap is ClingWrap, so I wrapped the squares. It worked for the most part, only by the end the melted styrene had accumulated into the side folds. But it's better than having to pry the squares from the frame. Especially when the bonds are still fresh and malleable.

The process was repeated for the other 7 LOWEST UPRIGHTS. The uprights were flush against the edges as they should be. The annoyance here was waiting for each piece to set before putting a new one. You see, I only have two squares. I would have bought more but they were $7 each. Wife said no. In the end it just meant taking a little longer than I wanted because it was about 1o minutes for each piece to set enough that I could remove the squares without disturbing the balancing act. But it worked. You can see this here:

In the above photo, the ANKLE INSETS are installed onto the cut edges. Nice! Dave's a genius in spite of his insistent usage of that communist metric system (I think he just got used to it from when he was kidnapped by the soviets and forced to draw droid plans for them).

Slowly the frame took shape. You'll notice I did not use any extra supports on the uprights like I've seen others do. They glue little triangles on the sides of each upright. I was afraid that if I did that it might hurt in the long run. I intend to make this droid an RC droid, but Dave's RC plans haven't been smuggled out into the free world yet, so I thought it would be best not to mess with his design. I didn't want the extra supports to get in the way of some gears, servos or whatever.

As seen above, I used blue masking tape to keep the pressure on the pieces being glued together. This allowed me to move a little faster and perhaps get it done and clean up before my wife got home with her new hair.

While I waited for the glue to set, I fiddled about with the FRONT VENT INTERNALS. There used to be a link to a tutorial on how to make those from styrene. Unfortunately I lost that link too. So I printed out the official club blueprints for the FVI and glued pieces to scrap .040" (1mm for those whom Lenin liberated from capitalism) styrene. I cut out the pieces and tried to make sense out of them.

By the way, I was able to get good round cuts using an 88 cent scissors. I think it came from Walmart a few months ago. I don't remember. I did finally make sense out of how to position the pieces and ordered front vent surrounds from our pal Keith Henry (of who's recently landed back on Earth.
The finished frame:

Another styreme frame is born! You can't see this in this photo but the SHOULDER SUPPORT PLATES are being held to the SHOULDER PLATES with #6 screws. Home Depot had no 3mm screws and the difference is minimal. Maybe if they ever switch the logo from orange to red. The tap in front of the frame is however 3mm (close to 1/8" for those who like money).

I measured the central hole in the shoulder plates, it came to about 1-1/8 inches. I used a woodboring bit just the right size for it. You see, nothing "precise" goes into that hole, so it doesn't need to be perfect. Studying the plans showed me that this is just for wires and cables. The shoulder hub that unites the legs to the frame is dependent on screws, not the centre hole. This isn't Victor Franco's wood assembly where you stick a gas pipe through (Thankfully)! The styrene droid is a lot lighter.

What I didn't do: I did not cut out the opening doors in the front, nor did I cut spaces for servos or hinges for opening doors. I think if I were to do that, I'd have gone the long way to get the perfect shape. I'd have taken a mold from the curved closed door and cast a fiberglass door from it. I don't really need an opening door though.

Now I test fitted the skins. Looks prima! I didn't bother taking off the paper template yet. I'll do that soon. I need to untape the skin off the frame and start thinking of how to put it back on with the Weld-on.

I have found out Weld-on evaporates far too quickly to really work it very well. I also stupided my overpriced applicator bottle. Melted styrene clogged the tip of the needle and I decided to cut off the top with pliers. Stupid idea. It shut the opening closed forever. Today I need to drive 15 miles to NoHo to buy another bottle. I have a bigger one, with a wider tip, but it's hard to control the flow with that one. The gauge is different on the needle. I found that applicator bottle is made by Silgan, the company that makes the bottle for Listerine. They don't sell to the public. But the same bottle is used for applying henna temporary tattoos, so you can find them for sale online. You can also buy them off eBay for $3 for at least one seller. I just don't want to wait.

I really, REALLY want JAG's aluminium R5 dome.

Wife says no.

1 comment:

  1. Boy, you're fast. That frame looks great, and the skins look beautiful. If you spent as much time building than blogging about it, you'd have a complete droid by now... then again, so would I if I wasn't laughing that hard reading your blog.

    Be assured that we in the People's Republic of Just About Everywhere Else follow your progress with interest and more than a little envy. We just can't duplicate what you're doing until our scientists find out how many picohogsheads go into a megafortnight. And they're still too stumped about how you took the nuclear waste we shipped you and use it as glue.

    Oh, and your wife and mine should probably go have a beer some time... they'd get along great.