Well, I finally got to the point where I could balance and check the CG.
I have to admit, I'm disappointed. The batteries are still further forward than I'd like them to be. It looks like I will have to add an ounce or so of nose weight after all. I was hoping the motor would be enough weight to enable easier positioning of the batteries. If I had NOT gone with the lightweight X mount, it might have balanced better. I was thinking when ordered the lightweight configuration that the extra weight of the motor would be enough. In hindsight, I should have gone with the stock configuration on the 4315-480. I contacted Ken and he said he could reconfigure the motor for me, no problem. He also observed that it is dead weight either way, so I could reconfigure the motor or just add lead weight and leave the motor alone. I think I will leave the motor alone. With this motor, I'm sure an ounce or so up front won't even be noticed, so it's no big deal, I was just hoping this configuration would be "cleaner". Haven't checked the watts yet; ran out of time last night; will do that tonight or sometime this weekend. Weather sure doesn't seem like it will be nice enought for a maiden flight any time soon. I uploaded a few pics of the configuration.

Originally Posted by SnowDog1974

Well, I finally got to the point where I could balance and check the CG.
I have to admit, I'm disappointed. The batteries are still further forward than I'd like them to be. ...a maiden flight any time soon.

I'm a little bummed to hear this since I just received the same motor for my 58".

SnowDog, what size batteries? Maybe a little larger battery might help?

Originally Posted by mdv

I'm a little bummed to hear this since I just received the same motor for my 58".

SnowDog, what size batteries? Maybe a little larger battery might help?

mdv, the batteries are 2x3s2800s from Value Hobby. These are 8.3oz each, so battery weight is 16.6oz.

Yes, a larger battery might help. I'm not worried about the ounce or so of nose weight that I'll have to add, just a bit disappointed. Did you get the lightweight x mount, or the regular mount for your 4315?

I'm going to investigate further tonight; based on the fact that the 4315 is an ounce or so heavier than the 3620 that others used, and they had to add an ounce of weight, I figured this would work out fine. It was late last night; maybe I missed something?

Maybe I'll try some of these batteries:

http://www.valuehobby.com/power-syst...1-1v-lipo.html

Originally Posted by SnowDog1974

mdv, the batteries are 2x3s2800s from Value Hobby. These are 8.3oz each, so battery weight is 16.6oz.

Yes, a larger battery might help. I'm not worried about the ounce or so of nose weight that I'll have to add, just a bit disappointed. Did you get the lightweight x mount, or the regular mount for your 4315?

I'm going to investigate further tonight; based on the fact that the 4315 is an ounce or so heavier than the 3620 that others used, and they had to add an ounce of weight, I figured this would work out fine. It was late last night; maybe I missed something?

Maybe I'll try some of these batteries:

http://www.valuehobby.com/power-syst...1-1v-lipo.html

I'm not sure you need to add the lead weight. My setup is the A40-10s (7.43 oz) and a 4s 4000 (15.2 oz). The motrolfly site says the 4315 weighs in at 9 oz without x mount. If I use that number and your battery weight, I figure that I have 2.57 oz. less weight up front then yours.

I glued a piece of a plywood up front to shove the battery under and I used epp foam to give it some padding. This way I can just slide the battery in and simply stick a strap around the back of it. With this setup, the plane is perfectly neutral and flys great. If you build the little box to slide the batteries into so you can slide them all of the way forward you should be able to obtain a slighty nose heavy cg without the lead weight.

Originally Posted by joesmith285

I'm not sure you need to add the lead weight. My setup is the A40-10s (7.43 oz) and a 4s 4000 (15.2 oz). The motrolfly site says the 4315 weighs in at 9 oz without x mount. If I use that number and your battery weight, I figure that I have 2.57 oz. less weight up front then yours.

I glued a piece of a plywood up front to shove the battery under and I used epp foam to give it some padding. This way I can just slide the battery in and simply stick a strap around the back of it. With this setup, the plane is perfectly neutral and flys great. If you build the little box to slide the batteries into so you can slide them all of the way forward you should be able to obtain a slighty nose heavy cg without the lead weight.

Thanks Joe, I'll give that a try. I think Bivens did something similar; sounds like that's the approach for success with this airframe. Now I just need some good weather for a maiden!

Originally Posted by SnowDog1974

Thanks Joe, I'll give that a try. I think Bivens did something similar; sounds like that's the approach for success with this airframe. Now I just need some good weather for a maiden!

Not a problem. If you try pushing the packs forward then you will definitely have a safe cg for a maiden. If you still don't like the cg after flying, then adding weight will be fine. You'll never notice the added weight.

Originally Posted by joesmith285

Not a problem. If you try pushing the packs forward then you will definitely have a safe cg for a maiden. If you still don't like the cg after flying, then adding weight will be fine. You'll never notice the added weight.

Yeah, I didn't think the ounce or so would make much difference...just make it easier to manage the battery packs.

Can you send me the component that will allow me to fly even half the maneuvers you do with this plane as well as you do in your video?

Hey...aren't you supposed to be in school today?

Originally Posted by SnowDog1974

Yeah, I didn't think the ounce or so would make much difference...just make it easier to manage the battery packs.

Can you send me the component that will allow me to fly even half the maneuvers you do with this plane as well as you do in your video?

Hey...aren't you supposed to be in school today?

Lol, it's a special mix in the radio, I can't give it out though

I'm in my web design class

Originally Posted by joesmith285

Lol, it's a special mix in the radio, I can't give it out though

I'm in my web design class

So RCG is just research?

BTW: My 4315 (lightened version) was 298 grams with x mount and prop adapter installed.

Originally Posted by 6L6Amp

So RCG is just research?

BTW: My 4315 (lightened version) was 298 grams with x mount and prop adapter installed.

Of course

That means he has an additional .5 oz up front from the previous number I posted.

A total of 3.07 oz

So I should buy the 4315 with the normal x mount?

Also, Snowdog, what standoffs did you use with the 4315?

Originally Posted by zmonster97

So I should buy the 4315 with the normal x mount?

Also, Snowdog, what standoffs did you use with the 4315?

I used "custom" standoffs...they are 7/16" in length; I'm pretty sure a 1/2" length would work just fine too...you can find nylon spacers at your local hardware store. This was just what I had on hand.

Originally Posted by SnowDog1974

I used "custom" standoffs...they are 7/16" in length; I'm pretty sure a 1/2" length would work just fine too...you can find nylon spacers at your local hardware store. This was just what I had on hand.

Thanks. Thats the lightweight mount, right? Would the motor length change with the different x mounts? I should go with the normal x mount, right?

Originally Posted by zmonster97

Thanks. Thats the lightweight mount, right? Would the motor length change with the different x mounts? I should go with the normal x mount, right?

Why do you want the heavier one? What's the rest of your setup?

Originally Posted by 6L6Amp

Why do you want the heavier one? What's the rest of your setup?

Because snowdog said he still needed nose weight with his. And I will be using 2x3s 2200mah batteries so they are pretty light.