My First Electric
Far be it from me about being an expert on electric airplanes. I supposed I could have just decided to never get in to the newest craze of model aviation, but I was kind of put into a position that eventually I just had to start building one. The following is excerpts from my first experience at trying to build an electric foam airplane. Of course there is a lot of exaggeration in what follows, but for those of you who have done this before, you may get a laugh, and for those of you who have never built one of these, it might just give you a little "heads up", but don't take anything I say seriously.
The kit was a GWS A-10 Warthog that Michael decided to purchase from Tower Hobbies. He wanted me to build it for him when he was home from Iraq on leave in a "Desert Storm" paint scheme. Of course it had to be a "twin engine" model.
(Click any picture to enlarge)
When the kit came UPS, I opened up the box and found the instructions and started to read the "broken and translated" "Japanese to English", directions to make heads or tails about what I was going to get into. After procrastinating for what seemed like forever, I finally broke down and started to put the thing together. The first thing I discovered is that I only had a ruler that read in centimeters. All of the measurements were in millimeters. Hmmm, lets see. How many millimeters are in a centimeter. It only took me about 15 minutes to look it up in a conversion table I had from GE here at home. For the record, there are 10 mm in 1 cm. I am "metric" stupid. Sorry!
"Cut a plastic tube as shown in the picture of 235mm" There was only one plastic tube in the kit. I cut it 235mm and placed into the "grove for easy way". They meant "groove for easy access". There were 2 plastic molded pieces with many tiny parts on them. I was concerned after the model was finished, because there were so many parts left. Turns out this set of plastic parts are used on several different models that GWS makes. You are going to have a lot of parts left over.
"Glue tube securely only left side fuselage" O.K. I got out the tube of glue they provided for the model and glued it into place per the instructions. Guess what? The glue never did dry. I don't know why it didn't dry. I left a dab of it on the model table for 4 days, and it never did cure. Am I missing something here? Back to the hobby shop to buy some connectors for the battery pack and some Great Planes Pro "foam safe" CA. Wiped away the wet GWS glue from my plastic tube and threw it and the tube of glue in the garbage.
O.K. I have never been big on CA. I know there are plenty of people who build with it. I know it's quick and easy, but I have reactions to it when it is used, so I try and stay away from it. I guess I am "old school". This CA was different though. It was "odorless" and it would appear that this would be the answer to building this thing quick. I glue the tube into place. I wait and wait and wait. It never really cures. I guess I need some "accelerator", but it is 2:30 in the morning on a "not planned" vacation day, so I can get it done before Michael has to report back to Kansas City.
I decided to push aside all of the new glues, and get out "old reliable" Sig Bond" wood glue and my 30 minute epoxy. Now I am in my comfort zone. The "Sig Bond" did a really nice job of gluing the foam pieces. When used in thin spare amounts, it dried and set in 20 minutes. Lots better time then the other stuff for me. Finally, push rod number one in place.
"Cut a 200mm plastic tube" OK, I'm lost. They only gave me 1 "plastic tube" in the kit, and it was only 400mm long. You do the math. I have a "plastic tube" that is only 165 mm long and they want me to cut it to a 200mm length. I don't get it. Oh well, back into my old
bag of tricks. Into my spare pushrod parts, and behold, a "golden push rod" will sub nicely here. After getting settled, it is now time to glue the 2 fuselage halves together. Keep in mind that the model comes painted only one color. Watch out for those darn fingernails. Oops, too late, more white spots and cuts of exposed foam. O.K., back to the directions.
"Make sure parts are on correct station, then join fuselages together, then fasten with paper tapes and hook and loop strapping" What....?? Glue the fuselage I think? Had to use epoxy here. I couldn't even imagine using the GWS glue for this. It would just fall apart. Guess what? When you take off the "paper tapes" you can kiss the GWS paint scheme goodbye. After this frustration, I decided to use a whole lot of little rubber bands and straight pins to keep things in place. Now all I have to do is glue the hinges in place for the flying surfaces. (No rudder control on this model, and the wheels are funky looking. Oh well.)
I finally figure out most of what they are talking about later in the building process. Now the hinges and control surfaces. Hey? Where in the heck are the hinges. I look at all of the left over plastic parts. There isn't anything that looks like a hinge. What....?? Paper hinges? Are you serious? Not for me. I have my tiny plastic "Klett" hinges that I use on everything. Ah!, much better. I know now the control surfaces will not fall off. New model builders! This model was difficult, at best for me to build as well as frustrating. It is "not recommended for beginners" as per the instructions, and they are clear about this model being for "advanced pilots". There is a whole lot of assumed knowledge that is expected if you are going to build this thing with "their' instructions. Now the electronics. Where is the receiver battery? What....?? There is no receiver battery. OK.... So now I get to use the battery pack that can "Burn Your House Down" if not charged correctly. What....??? "Warning, Lithium Polymer batteries are extremely dangerous." "Charge only in a fireproof container" "Never charge batteries unattended" "Never charge batteries in your model"
Are you for real? I apparently will be using an explosive device to fly the new model airplane, that can also burn up on impact if it crashes, as if nitro glycerin were on board. And the AMA is worried about our Space Shuttle....? Right............!
I could not believe the high currents that these Li-Po batteries put out. Man oh man have I been behind the times. Now I have to buy the Li-Po special battery charger, and Michael goes to the Army Store in Fairfield to get me an ammunition box to charge the batteries in. I realize that these battery manufacturers have really come together to make these new packs safer. The good ones have electronic voltage cutoff monitors built right into the packs and safety fuses too. I am not as concerned now as when I first started to read about Li-Po batteries.
Ok, now I am ready to try out all of the electronics. This is something I finally know something about, and I can tell you, I am truly amazed. 30 Amp ESC's...?? (electronic speed controllers) Yes AMPS. All on a pc board the size of my thumbnail. Oh no! I just discovered another potential problem. What am I going to do if the motors quit and I loose battery power. Are you sure I don't need a battery pack for the receiver?
Not to fear, not only does the ESC cut off the voltage to the electric motors automatically, but there is still enough battery power left to land the model with power to the receiver and servos. Unbelievable. The "FMA Direct" 30 Amp ESC also allows you to program braking on the motors and monitor the Li-Po battery voltage as well.
Almost ready to complete. Still have to paint the darn thing. Go to Hobby Lobby to try and purchase some dark brown spray paint that will not eat the foam. I can not find anything that "guarantees" it will not hurt the foam when applied. Now what. All I need is to start spraying paint after all of the Hell I have gone through building this darn thing, and watching it melt like the "Wicked Witch of the West" in the Wizard of Oz.
I end up at "The World of Hobbies and Games" at the "Micro-Center" mall on Mosteller Road in Sharonville. I must say I was really impressed with this place. They are just getting started there, but boy have they picked up the RC part of our hobby. Given time, it is really going to be nice. You need to check it out.
Anyway, I found a can of "Tamiya" paint in "Nato Brown". They have all kinds of colors for foam airplanes. My only concern was that the can said that the paint had "acetone" in it. I mentioned it to the clerk and asked if the acetone would hurt the foam. He really wasn't sure, so he gave me a $1.99 white foam airplane and painted it just to make sure it would work. Great. No damage to the plane. Finally finished the model. What an experience. I sill need to have the "foam experts" in our club check CG and stuff, but it sure does get up and go on the ground, and I am really happy with how it turned out. After about 42 hours of work on 3-4 hours of sleep per night, the plane was done on Michael's last day here. We never would have been able to fly it any of the days he was available because of high winds and rain, but he did get to taxi it around in the street and take some pictures for me. I sent them to Bob to put one or two in the newsletter if he had room. I will have it at the next meeting too. It needs the "foamy boys" blessings. Gee, I guess that will make me a foamy boy too!
(Brother, I have to do something with those wheels).
David A. Polley