I am just about done building a graupner cap 232 ARF for a friend and have a few questions:

1) it looks like the fuel tank is to be mounted right behind the nose bulkhead, forward of the wings and CG. Won't this greatly affect the CG when filled? or is that were it goes and I shouldn't worry?
2) the radio equipment came with a 6in long X 3inch wide piece of foam-rubber, does this get rapped around the reciever or the battery?
3) What do i do with the antenae lead wire? fish it down the fuselage? Extend it down the outside of the fusalage and secure with tape?
4) lastly What's a good method to break in the 2-stroke engine?
Thanks in advance

1. That is where it goes, don't worry, Ballance it with an empty tank, the full tank won't affect CG that much and the affect is positive.

2. Both. You want to wrap both in foam to protect them.

3. What ever you want, just don't cut it. I put a piece of clear tube like bike spedo cable outside or nyrod inside the fuse for it to go through and come out the tail, or you can put it through a hole in the fuse and tape or use a rubberband to mount it at the tail.

4. Get help from someone at the local field so they can teach you the propper method and save damage to the engine plane or you. It isn't hard, but if you get help, you won't be tempted to try to fly it yourself. If you try to fly it yourself, you will crash it.

Mike73,
Lots of question... I am new also, but I can give you some answers. Take them with a grain of salt.
1. My Alpha has the fuel tank behind the firewall and forward of the CG. I don't have a problem flying it. When the fuel level gets low, the nose tends to raise a little. It is fine.
2. My plane has the foam setting over the receiver and battery, but I also have some foam that is cut to fit the parts, which craddle them.
3. Put the antenae down the fuselage, but put it in a small plastic tube near the servos and CA the tube to keep it from getting tangled with the servos. Your can tape it at the end, but I am not sure it is necessary.
4. Cannot help you with with breaking in the engine. I have some idea, but would prefer you get some advice from someone with a little more experience.

Michael

you guys are quick and great, not flying it will be hard, it's a gift for my father-in law, my mother in-law bought it, I'm just putting it together. But spending the time and energy and knowing I won't be flying anytime soon is killing me. But I sure don't want to crash the thing (before he can!)

Its a fun hobby, but I see new people all the time fire up a plane and decide to "just taxi" and it usually ends up getting broken. I have seen the same thing with ultra lite aircraft. One case the guy spent 6 hours in surgery, the other case the guy won't do it again. Not good.

3. You can mount antenna anyway you want to but keep this in mind.
Metal will shield its reception, so don't use any metal tube. Also, metallic covering can also shield it. What I have on my plane is pressure tubing. Like for pneumatic air systems, just some things to keep in mind...
Have fun

As for breaking in the engine...

Some people have very complex rituals for breaking in an engine (rotate prop 3 times whilst facing Mecca, etc.)

I find that if you just run 2 or 3 tankfulls of fuel through it while it is running on the rich side works for me. (I even usually run those with the plane in the air!)

What did you mean by don't cut the antenna? You mean like don't cut it off or don't cut it anywhere period? Because I hooked mine to my fin with a T-pin, a rubberband, and part of a servo arm. But I also shortened it a bit... is that baaaad?

I can at least ask the question.
How much did you cut off and how much is left?

You should NEVER cut the Rx antenna. The length (about 39"), isn't random, antenna legth is based on the Radio system's operating frequency (72 mHz). If you only cut off an inch or two you're probably alright, but I'd still do a good range check. With Tx antenna collapsed, you should be able to walk out about 100 feet from the plane without the servos "chattering", and still have good control over them. Much less than 100 feet is suspect.

Some small park flyer Rx's use 1/2 length antennas (about 17" instead of 39"), but the range is reduced to about 500 - 800 feet.
Dennis-

AHH, mounted the engine (recommended by the hobby-lobby for the plane) today and the muffler hits the landing gear and gear mount! Are there spacers available to extend the muffler body out further away from the engine and fusalage?

I only cutoff an inch or two... I didn't know you aren't supposed to cut it... How do I fix it? Can I send it back and have a new antenna put in? Do I have to buy a new reciever? Help...

You might be able to solder on a new one if you can find the material. There are muffler extensions available, check tower hobbies.

You can just solder the piece back on if you still have it. If not get a piece of the same gauge wire, cut it to 39" and replace the original.

Aviation Nut,
If it was just an inch or two, I would do a decent range check as I mentioned earlier. If it checks out alright, don't worry too much about it. Just don't fly out or high enough for the plane to become a speck.

You CAN solder on a new antenna wire (same gauge as Minn stated), but you need to be competent at soldering. Soldering a
piece back on can also be done. In either case, range check it after!

It can also be sent back to the manufacturer for a new one.

Mike,
Can you rotate the engine mount about 45 degrees counter-clockwise? It will often cure the muffler issue.
Dennis-

Yeh, but soldering a new piece on would create a higher resistance in the wire, wouldn't it?

About how much would it cost to get a new antenna put in it? Or would it be cheaper to just buy a new reciever ($60, I'd just have to put my crystal in it)?

If you buy that new Rx...... could you mail the old one to me!!!! Just kidding of course. Seriously, I would surely not buy a new Rx because of any antenna problem. If you feel you need a new antenna for peace of mind, call or email these people. They will be cheaper than the manufacturer, and they do good work. I have used them twice to repair radios. Their labor charges are very fair.

http://www.radiosouthrc.com/

Good luck .....lownslo....

Bob

Ive heard of them too. That is the company most of the people in are club use when we screw up. Just a question, would solder effect the frequency reception? Would it change the range or effect it in control or something wierd like that? And how are the orgional ones put in? I haven't opened one up(by crashing of course,) and looked at the way they are attached.

Soldering won't affect the resistance.

Solder will effect resistance, but not much at all, It would be hard to measure with a meter. If you all say it is OK, I would recommend soldering on a new piece of antenna.

The antenna lengh is not nearly as critical as many people think. If it where that critical, then it's position would also be critical, ie, in a striaght line. Also, if it was that important, you'd have to adjust the length for the different channels. Fact is, a Channel 12 RX and a Channel 60 RX have the same antenna length, even though there should be a few inches of difference. Heck, if you chopped off 2-3 inches, depending on your channel, you might have improved things . Most installations have the antenna bent around things a few inches here or there anyway.

Not only that, but some recievers can have up to half the antenna cut off with no reduction in rage at all. Specifically, FMA receivers are very non-sensitive to the antenna. I'm talking about duel conversion FM units here, btw. I think Futaba might be more sensitive to antenna length, though I'm not sure.

I have several antennas that have been dynamically shorted, one by quite a bit. Do a range check (engine off and running) and if it checks ok, you're good to go, regardless of the antenna length.

If you want to lengthen the antenna, it's not critical either, just go to radio shack and get some wire that is close, and solder it on there. I've seen planes with 4-5 splices of different kinds of wire in the antenna, and they worked just fine.

Oh, and fwiw, all my "work fine" is in combat matches. Combat is absolutly the worst envrionment for radios out there, if it works in combat, it will work while you are sport flying. We sometimes have 12 airplanes up at the same time, witht he pilots standing at random spacings, sometimes 3 or 4 guys nearly shoulder to shoulder. It's amazing what modern radio gear will tolerate, the stuff has gotten really good over the last few years.

I called Hobbico in Champain, Illinois and I'm gonna mail it there. It'll cost me less then $20 to get it repaired. They said they could send me an antenna but if we solder a new one on or whatever it'll void the warranty on it. Plus I rather be on the safe side and have it correct, lol. Makes me kinda nervous thinking that my plane might crash from a shortened antenna.

Same here, Heck if I did that, I would be so worried I would either not fly it or crash it right away. lol

i think you are not supposed to kink the antennas either.

or wrap them around the langing gear. my friend did that, lets just say he was able to finally fly w/o an instructor(ever) his plane got about 800 feet away and went crazy. it flatspun into oblivion

Right, you shouldn't kink or double them up or wrap them around anything.

What I was talking about was the short length where the antenna goes from the RX to wherever the "long straight part" starts. And then there is the bit at the end when the antenna is too short. I frequently run my antenna back along the fuse to the root of the vertial tail, then up the tail, then either let it tail off behind there, or sometimes back down the TE of the vertical tail. It's far from optimal, but even in combat, I've never had a radio hit.

Combat Addict, not to pick on you too much, but if you're that nervious about a little shortening of the antenna, you're going to have an intersting time in combat. My earlier comment about a "dynamically shortened antenna" meant one that got cut by someone's prop in a combat match. I've had it happen more than once, and I've still never had a problem. (I've never had one cut really short, just lucky so far. I did have one break right at the RX though. Soldered it back together and it's in service now).