Sunday, June 26, 2011

CPU Armed Painted and Misc stuff

I haven't updated here in a while but I've been busy with some parts and waiting for things in the mail.

I'm pretty much done painting the CPU arm and I have the servo attached! Painting the arm was much easier than I thought. Here's some of the basics so you can get an idea on how to paint yours.
I masked up the tube and painted it black. I didn't use any primer on these parts. I don't know why, I just didn't.
You do the same with the tip. Cover up everything with blue tape that you don't want paint on. This section I'm painting anodized blue, same can I'm using for R2 blue on the droid. Clearly some areas will have over spray. Take a Q-tip and Acetone and clean that off. If you happen to mess something up or don't like how it turns out. You can just wipe the paint off with a rag and Acetone, its nearly an idiot proof.
I painted 2 sections a day until I had the tip done. It took about a week or so to get it how I liked it.
It turned out pretty cool. I might add a few more color details to the arm. I tried to but couldn't get the paint how I wanted it. Eventually I want to add the wall section that this tip plugs into.
My idea of putting threads on this servo rod also worked in my favor. I hooked it up to my droid and tested it out.  The servo is able to move the tube around, so far. However when doing that I realized this particular servo isn't going to work. Its a default clockwise servo. I need a counter clockwise servo so it move up. I might as well buy one with more torque while I"m at it. This servo will end up moving the gripper up and down.
Yesterday we had a local R2 build day. We focused on R4 domes this time. Droid Welder has a styrene R4 dome from a small limited run years back. So we copied that or he did for several builders in town. It will take 2-3 people to bend one of these and hold it and glue it together. I think before I try that I'll copy this onto some sheet metal and bend that up and see what happens.
As if I didn't have my hands full already. My other JEDI control kit for R2-Q5 is here and ready to activate that droid. I haven't really thought out where and how this will go in that droid yet. I'll need to let that simmer for a bit.
My droid hasn't worked for a while because I'm upgrading some electronics. Here I have one of Dan's power distribution boards mounted to an aluminum plate I painted blue. It powers the JEDI control and what you see on the other side.
This is the other side. It has four Syren 10a Motor Drivers on it. They power the dome motor, CPU actuator, Gripper actuator  and dome lifter. I don't have all that stuff quite yet, but when I do I have the electronics to power it already installed inside the droid. All you have to do is plug in the red and black wire to each Syren 10A and its ready to go and control with the VEX transmitter.
Upgrade complete! Power is restored back to the droid via the power board. I also installed a new Pittman motor so the dome is spinning again.
I also installed the new amp on the back side of my electronics panel. Its not quite loud enough, not as loud as the previous amp. I wonder if there is something else I can do?

Monday, June 13, 2011

CPU Arm Painting

I'm waiting on tools and motor controllers and always something in the mail. So I'm painting the CPU arm as I go.
Here is today's coat of yellow,  yesterday I painted the black rings. Tomorrow I'll do a run with red and black on the tip. If you screw something up you can always remove the paint easily with a cloth and Acetone. I'm not very good at hand painting things like this where you basically need a magnifying glass. I'm used to 'can't see it from my house' level of quality.  I did some research on this part before I jumped into paint it. There are a couple of different tips of the arm from different movies. I'm going with this photo below.
So I'm on my way to make my CPU arm like this one during the end of A New Hope. But my tip is different but maybe in the future I can machine that type of tip and upgrade. You can always upgrade as you never finish a droid. You just keep upgrading them with better parts!

Friday, June 10, 2011

Misc work on various parts.

Another Don Jar part breaks. During the break down of R2-Q5 while taking the legs off the taped screw that holds these leg struts to the ankle cylinder failed this piece fell 14 inchs and hit the floor and the center piece broke. Sorry Don but your parts look nice but are made out of *#&@. Nearly every single part I ordered has failed, cracked or is in the garbage. Superglue will fix this but for how long? I need to look into getting quality parts.
The octoports are turning out nice. The octoport on the right still has the masking tape on and the octoport on the left I've removed it to show the finished piece. Now the tricky part is installing this on the skin which isn't so easy. Most of my building now is only on the weekends as I'm backing running 5 miles a day to keep fit.
Here are both skins sitting on some cardboard. The octoports are ductaped into position. The I used of course, JB weld on 4 of the 8 sides. I gently used a heatgun to speed up the curing process, but can't use it much or it will warp the resin parts.
JB weld takes 24 full hours to completely cure so you'll need to baby sit this during the process. Every 2-3 hours go and check and make sure the octoport hasn't slid out of position you need it or there's going to be problems. Another issue is the octoport won't want to stick tightly to the skin. It will want to lift off, which is why I'm using gravity and pressure to attach them.
So to keep this curing tightly to the skin I put a brick on top of them. That's right a brick works perfectly. Not too heavy to crush the resin and not too light and it did the job. So ductape, JB weld and a brick are how I attached them to my skins. The next day I took off the brick and they were in installed perfect. I then JB welded the other four sides of the octoport and will paint them black the next day.
New amp arrives! The amp on the left I just took out of my droid. The amp on the right will replace it. Its  very tiny and just as powerful if now more powerful. This not only saves very valuable space. It saves a whopping 4 pounds because there was a steel plate the amp was attached to that's no longer needed now. That's a lot when your droid weighs 200 pounds. When means its more efficient and will result in longer battery charges than keeping the same priced amp which weight a lot.
Its always a great day when servos come in the mail. This is about $100 worth of servos and attachments. What we have here are 2 servos that will be attached to the utility arms to open and close them. Then I have 1 heavy duty torque servo that will be attached to the CPU arm. I got one that was rated about 3 times the weight of the arm. However I never weighed the arm but I assume it don't weigh 8 pounds. Making this arm work is my next major project to complete this summer as you'll be reading updates on this blog with my progress.
Here is my basic plan. I bought his 10 dollar aluminum part to attach to the servo. That will then attach to the CPU am and when the large door is opened this servo will move the CPU arm 90 degrees up and down when I put the proper parameters into the JEDI code. I think my next step is to paint the tube. I don't want to get this working and then take it apart and paint because its not going to be easy to get it the exact position needed.
Here is a closeup of the parts. The hole in the CPU arm is already taped and the plug is taken out and laying next to the silver thing on the servo. So I'll need to find out what exactly  I need to tap or whatever its called to match the silver thingy with the groves so it screws into the CPU arm. Then the servo must somehow attach to the black breadpan and must be in the exact spot for it to clear the door. This is going to be one of the funnest things I ever do on this droid. This is my plan going forward and we'll see if this expensive R&D works. If it does I predict several dozen builders will copy what I've done if it works. 

Much credit to Paul and his 2-3 droids as I ripped him off forwards and backwards. Paul you can copy my brick construction work I listed above:)

Friday, June 3, 2011

Back to work droid building

Post Comic Con its time to do a total droid break down. Install new parts and fix things that have broken and get to work on those servos.
I got my EL wire in. Interesting stuff to mess with. Here is a quick test as it makes this tinted dome more interesting.  I plan to change all the brains inside this dome. I thru this together to have some electronic details of something for the con. 
Turn it on and its looks like glowing speaker wire. It looks cool when you blind them in different patterns. Maybe I'll get some more of this stuff and get the thicker versions. I love to play with this crap. I'm just a big kid with a checkbook now.
Since I ended up super gluing my last Octoports to my hands and mashed them I ended up with these new resin Octoports. They are a bit warped from shipping but no big deal that's easy to fix.
I cut a piece of scrap aluminum from a messed up footstrip to widen it. Then just used a heat gun so it bent back into shape. Then I through it in my freezer for 15 minutes. A round or two doing that process and they're ready to prime. These will be primed, painted silver and then black:)
Dome failure: My dome seized up on Friday at the Comic Con. It noticed it suddenly started turning slowly and then stopped completely. Being a rookie I thought the batteries must be dead. After recharging them it never worked properly that weekend again. So during a tear down of the dome drive system I found this after taking the wheel apart. Under the dome it was scrapping onto metal from the looks of this and that caused a pile of debris.

Before I got to this point, looking at the Pittman in this bracket there was a pile of aluminum dust around the drive shaft of the motor. That worked its way down I think and gooped up in the grease and seized the motor. I could be wrong but that's the best I can tell right now. 

Maybe the stress my spring has on this motor slightly bent the center shaft. 
The gears inside the Pittman show no sign of damage. I wonder if you can just buy the center drive shaft because that probably gets chewed up the most. So I cleaned this up and greased it all up and its nice and smooth spinning like its brand new. I think I brought this motor back to life. But my dome is too heavy for this type of motor and I need to look into upgrading to a new motor system in the future.

I also made a servo bracket since velcro won't work for the job I'm trying to do. This will mount onto the back of the breadpan for the Gripper side of the droid's large door. This servo has an aluminum arm so it can withstand heavier stress for these doors. 

I've been working on/off on this for a few days now. You have to have the arms in just the right spot with just the right mounting system. If you don't either it won't work at all. Then if you get it to barely work you need the rods at just the right length with everything tweeked just right. Fun stuff to do, I waited a year to get to this spot and its cool as hell!
Now I have done a test fitting of my servo and screwed it to the back of the the breadpan. I cant' believe it works! Its not perfect and took a few tries at it but it opens and closes. 

It didn't open and close perfectly. You have to really, really, really tweak it to do that. I did get it working by writing some stuff in the startup file. Now I have the weekend to do this to the other large door, and then write a script that links them together so they open when the scream effect happens.