RE: CMP 120 Zero ARF Build thread
 

I would SERIOUSLY recommend that you reinforce the ribs to the main spar and the rib to the leading edge with some medium/heavy fiberglass and epoxy. The ribs of this wing are too thin in my opinion and even though there is a plywood doubler in the retract mount area, it is NOT glued in to utilize its strength! The weak point of the area is that the only glued area is where the solid portion of the rib slides into the cut out on the spar. Essentially the wood holding the ribs to the spar is about one inch of vetical height of 1/16" balsa. They should have just made the two gear mount ribs out of plywood, not balsa.

You cannot overbuild this area enough!

Hope this helps!

Bryan

RE: CMP 120 Zero ARF Build thread
 

Thank you for the kind words The cockpit took me a little over two weeks a very long and tedious process, had there been one available at 1/6 scale it would have made life allot easier. I love the weathering you did on yours. and thanks for posting pic, what did the finish weight of yours come out at ? I think I will be close to pushing 12.5 to 13 Lbs finish dry weight. Right now I am still working on the inner gear doors getting everything to function right and in sync with each other is such a pain ! I went back and I am re doing the wheel well area I decided to mold everything flush to the wing skin closer to scale then what I originally intended I have to say I am much more pleased with the way it is turning out. Lado retracts have to be the best thing since slice bread, the ease of installation has cut allot of time off of the normal air or even mechanical retract set up, just plug and play I will post some new pic of my current progress on the wing and retract set up

RE: CMP 120 Zero ARF Build thread
 

Zero:

My plane came in at 14 lbs even. It flew well, but the lighter, the better as you know. Even with a heavy gas up front and both receiver and ignition battery packs within the cowl, I added around 5 or 6 ounces of lead to the nose to balance. Keep this in mind as you are building, especially if you add stuff like tail wheel mods, etc.

Bryan

RE: CMP 120 Zero ARF Build thread
 

Zero , the plane looks great , never got to see the interior when you were building it , really great work , its amazeing that the rc community can make such great interiors vs the ones we have to choose from the big guys selling them
Really nice Job

RE: CMP 120 Zero ARF Build thread
 

LOL thanks God knows it took long enough, I spent my two week vacation on it and still had to go back and touch up a few spots, funny thing is every time I think I'm close to finishing this bird I see something else that needs to be redone or could be done better, I thought I was done with the wings a month ago.....then the lado retracts came in next thing you know I'm cutting the wing open installing new rails molding everything in .....oops got have inner gear doors just would look right without them LOL, I'm my own worst critic

RE: CMP 120 Zero ARF Build thread
 

LDM you ever finish up that P40 you were working on ? I don't think you ever posted pic of the completed plane

RE: CMP 120 Zero ARF Build thread
 

A few pic of the inner gear doors

RE: CMP 120 Zero ARF Build thread
 

yes the VQ has been done for a long time , now I am back on my FW190 ,
The gear doors look good , do they flap on the wing when open , assuming the hindges are tight and keep the doors steady

RE: CMP 120 Zero ARF Build thread
 

I am trying to solve that little issue right now, any ideas ? I'm thinking that as far as the door retracting up I have that solved, its when the doors are open how do you stabilize the door from flapping around ? the only solution that I'm going to try this evening is maybe two very tiny small magnets to work as a latch ? I'm trying to keep the look as clean as possible, any other suggestions would be greatly appreciated

RE: CMP 120 Zero ARF Build thread
 

himmmm , yes that is a good idea , you can even reverse the manets so that they will want to push the doors open and hold them while the gear idoor open , you then add a small spring to keep the tension on the inside door tight . The retracts then cycle , close and the magnets lose the battle until open again

RE: CMP 120 Zero ARF Build thread
 

You can get hinges that are spring loaded in the open position for just these kinds of applications.

RE: CMP 120 Zero ARF Build thread
 

or you can try this. Just a quick drawn MS Paint pic but you should get the idea. wrapp some wire around the tubes to solder a shoulder onto them then clean up the spring face by putting the tube in a drill press (or drill) and hit it with a file. while you're at it... hit the smaller of the tubes all the way up where it goes into the larger tube to reduce the diameter just slightly so it will slide easily. grease w/petroleum jelly or axel grease. I'll leave the upper and lower pivots to you-I used "U" channel brass in the next up sizes. You can pull/stretch the pen spring to give a bit more push.

In the picture I drew it as straight up and down...actually it works better if the bracket on the door is longer so the assy is at an angle when th door is open but then you'll need a travel limiter on the door as well. I put a limiter on the front of the door and the spring on the rear. when the unit is installed and working properly the door travel prevents the unit from just springing apart.

sold the plane and can't locate any pics right now.

RE: CMP 120 Zero ARF Build thread
 

can you give me a source for a spring loaded hinge that small, the ones I have installed are only 5/8" in width

RE: CMP 120 Zero ARF Build thread
 

frets , I had a similar set up in mind and although a simple concept it seems way to complicated for the room I have to work with, I would have to cut out more of the wing structure to have the room to get this setup up to function properly, being that I already cut it out more to go from a 3' wheel to a 3 1/2, any more and I know I will be compromising the structural integrity of the wing, had this not been the 120 size zero and perhaps bigger then this would have been perfect, if you don't mind I'm going to keep your sketch for future reference on bigger projects

RE: CMP 120 Zero ARF Build thread
 

Hi all I jus got a zero that has a 160 os. i have removed it and replace it with a 26 zenoah. First part of project is to do something with all the led that was glassed to the inside of the cowl. So i plane to move (Heaver 26cc Gas) foward about 3/4". Then make a custom exhaust, which is heave as well. I will see how she balances with the equiptment wher it is. I alos plan to install flaps and fix the cavity in the wing where to wheels retract to. here are some pics of the rough exhaust, needs fine tuning of course. When I get the balance right and I know how the exhaust will be mounted. I will flatted the tips that stick out the cowl... Yall let me know if what im doing is a bad idea or any thoughts at all.. Thanks

RE: CMP 120 Zero ARF Build thread
 

more pics

RE: CMP 120 Zero ARF Build thread
 

So the exhaust out of the cowl would be functional ? brilliant ! I would be very interested to see a close up of the exhaust hook up to the cylinder head

RE: CMP 120 Zero ARF Build thread
 

Yes the exhaust will be functional. I plan to make a really short header off the cylinder head pointing up, and use a piece of flexable heat hose to connect to the exhaust. The exhaust will be mounted to the fuse or motor mounts, and no vibration from engine should effect the exhaust...

RE: CMP 120 Zero ARF Build thread
 

Nicely done.

RE: CMP 120 Zero ARF Build thread
 

Having to make changes as I move along. Moved the engine foward 1" total. So im moving the cowl mount ring foward. I will add some extra cowl pieces to cover the gap that will be left between the cowl and the fuse. She seems to balance pertty good with the engine in this location..

RE: CMP 120 Zero ARF Build thread
 

Without details on the muffler I have to ask , 1)how was it solderd engine hear can be brutal on home made mugglers 2)it appears that you have advoided medal to medal contact from the pics , if not that would be a concern from vibration and possible radio interfernace .
Outside of those normal concerns the work looks excellant :D

RE: CMP 120 Zero ARF Build thread
 

Thanks LDM, I plane for the muffler to be isolated with a piece of heater hose. But could you explane what you were talkin about radio interfernace. Im using spectrum stuff.
O by the way. i sent my spectrum reciver back thinking there was a problem cause of a fatial crash. Along with 3 other ones I had for updating. They replaced all FOUR with NEW ones. Way to go Horizon Hobbies Service Department. these guys are the greatest.
Ok, back to the Zero. I will keep posting as work progresses..

RE: CMP 120 Zero ARF Build thread
 

"talkin about radio interfernace" yes even with spectrum , its been highly recommended that you never have a medal to medal connection in the engine area . The vibration can create interferance with the radio system simple example are -medal clevis to medal arm for throttle , instead use a plastic clevis to medal arm on throttle .
I take extra precautions even with muffler to engine contact , I use a good gasket .
So in your case if you have a part of the muffler touching the engine mounting bolts , you will get medal to medal and possible interferance .
Look in the gas engine forums under rule ect and best practices for engines. Again I am not an expert in gas , so all my info is from guys telling me from experience .
I had some guys swear that a servo for the throtlle on the fire wall is no problem , others say "no you cant do that " so its a learning curve !!!!
To bad about the spectrum receivcers , I useing my first one with my Fw190 , one problem is my flaps to a Y connection with an noise /amplifier -that is a no no on 2.4 systems .
So I am delayed in my build while waiting for a simple $10.00 piece from dion eletrics , its a servos reserver with no noise /amplifyer .
Remember do not use Y connectors with noise /amplifiers on your 2.4 system , stated clearly in there manual

RE: CMP 120 Zero ARF Build thread
 

hey can you post some pic of the exhaust hookup to the cylinder head , what muffler will you be using ? and how do you plan on pressurizing the fuel tank ?

RE: CMP 120 Zero ARF Build thread
 

i will post pics as soon as i get to that point. Im using a gas engine so dont have to preasure tank