paladin

My Feedback: (9)

The completion of the aileron servo lead is to spread the leads apart and cover them with E6000( maybe E600 ) at A C Moore. I put masking tape down on the wing, then on the wire to hold it inplace.

I made the box to hold the air valve and servo. Notice the air tubing between the wheel collars and the spool.

Joe

Sturtz

My Feedback: (20)

Joe,,, can you give me the cowl diameter ? Basically with the cowling off,, side to side and top to bottom at firewall.
Gonna get this bird and need the measurements for working scale exhausts.
Scott Ellingson from Brillelli Engines will be doing the custom fit with their new 36cc engine and custom built A6M5 exhaust stacks.
The new 36cc is narrow enough for a Spitfire, weighs less and has more grunt than a 40cc gasser. Should fly the CMP Zero great.

I have the SpringAir 704 series retracts with 1/2" Robart struts ,,,, 7"inches long . All the radio gear and most of the hardware.
One more question Joe ,,, what servos are you using on the main control surfaces ? Plane seems big enough for some MG, digital high torque for the rudder at least ?

[link=http://www.brillelli.com/brillelli_008.htm]Brillelli 36cc gas engine link[/link]

paladin

My Feedback: (9)

Sturts, here are the calculations I did before buying servos. I'll get some pics of the cowl with a ruler on it the next post.

While unpacking and checking it over I took the measurements needed to figure the servo size needed. The measurements I got are to follow:

Aileron
Length: 18.5in
Cord: 3
Assumed max airspeed: 120mph
Max control deflection: 15 degrees
Max servo deflection: 30 degrees

Elevator
Length: 15.25in
Cord: 3
Assumed max airspeed: 120mph
Max control deflection: 15 degrees
Max servo deflection: 30 degrees

Rudder
Length: 10.25in
Cord: 5.25
Assumed max airspeed: 120mph
Max control deflection: 20 degrees
Max servo deflection: 45 degrees

Flaps
Length: 13.25in
Cord: 3.5
Assumed max airspeed: 80mph
Max control deflection: 45 degrees
Max servo deflection: 90 degrees

While I have my own formula it is so similar to this one and it is easier to use. See the URL below:

http://www.morgantech.com/Servo%20To...0Caculator.htm


the results are:
Aileron each = 40oz-in
Elevator each = 33oz-in
Rudder = 70.5oz-in
Flap each = 95 oz-in

Plug my numbers and see if you get the same numbers

next pic’s of the plane and the cowl measurements.

Joe

ForkedTailDevil

My Feedback: (21)

Hey i just got done building one of these kits...wanted to give you a heads up on it if you havn't flown it yet. The CG that the plans call for i believe is 7 1/2 " back from the leading edge....well i'll be the first to tell you...ITS WAY WRONG!!!!! cg needs to be moved forward at least an inch. My zero is back on the building board because of that problem. First flight was so extreamly tail heavy I had full down trim and still had to keep the stick bout half way in the down position to make the plane fly level. Fortunately, i was able to get the plane back down on the ground and actually made a descent landing....had to shake the poopy out of my pants after that one. So i brought it back home and balanced it at 7", putting more weight in the nose, and tryed it again this weekend. Didn't go so great this time around...was still tail heavy!!!! the wind didn't help either...took three go arounds before I fianlly descided just to get it on the ground...i knew i was going to rip the gear out but i just needed to get it on the ground before it became a threat to any body else and/or their airplane. Yes the grea ripped out but lucky it just went strait back instead of through the wing...started repairing one tnight, so probly be back up in a week or so to try it again..i'm really dissapointed by the flying in it thus far..hopefully i can fix the cg problem...be looking for my post when i get some pics ready....good luck!

vertical grimmace

My Feedback: (1)

Keep your CG just ahead of the thickest part of the airfoil! This holds true for all wing unless sweep exists. Do not trust kits, ARF's recommendations. Knowing where a proper CG should be for a givin wing is not difficult and should become part of the knowledge base for any aspiring experienced modeler.

paladin

My Feedback: (9)

FTD, I'm sorry for you troubles. but thanks for the heads up!

Early in my modeling carrier I started using a moment diagram to reduce wt added in the rong place. but for first flights I ballence were the plans say then add enough wt to move the CG forward to 25%. I screw this weight on usually (in the case of the Zero) right in front of the cowl so it is easily removable. then test fly. once I;m starting to get comfortable with the plane I start to slowly remove the added weight untill it flys the way I expect. once happy with the ballence point I'll move the remaining wt under the cowl were it is better hidden.

! hope this helps

Joe

Sturtz

My Feedback: (20)

Joe, thanks for the great info and the servo calculator. Looking forward to your measurements of the business end of the Zeke so I can send the info off to Scott at Brillelli.

paladin

My Feedback: (9)

Kurt sorry for the delay. I'll get the pic's tonight and post tomorrow.

Joe

Oosiksmith

My Feedback: (1)

Why did you fill the tubes with foam? I just got the CMP P-51 140 and it has tube wings; instructions don't say anything about foaming wings.

paladin

My Feedback: (9)

Kurt, here are the measurements.
Hight at back 11.25
Widthat back 10.25
Depth to mounting ring 9.25
Let me know if you need anything else.

Oosiksmith, It’s just an attempt to get every bit of strength out of the components as possible. Buy foaming the center I’ve increased the strength of that component by a factor of two (roughly without doing the calculation) for a added wt of 2.5oz. I foamed the forward LG mountbox for the same reason. It in affect created an I beam between the top and bottom sheeting, and tied the LG mount to them while spreading the stress over the max area (reducing point loading).

Joe

Sturtz

My Feedback: (20)

Thank you Joe !!

paladin

My Feedback: (9)

Well, I’m painted into a corner! When I started this kit I was hurrying to get it done for the summer so I did not pay to much attention to the linkages and put the rudder hinges in before I saw what was provided for the stearable tail wheel. I looked at it and was shacking my head about it when I had to leave for the summer. When I got back I could not remember if I tossed the parts or if they were at the bottom of all the piles that had been left in my work shop. So as I’ve been building I’ve been going through the piles, with no luck. So the method I would prefer to employ is not practical because I’ve already glued in the rudder hinges.

The preferred method would have been to put a hard would block just below the last hinge and drill a torque rod anchor hole in it. Then run the torque rod down into the fuse anchoring the other end in there. I probably would have used 1/16 CRS because it would have flexed and acted like a servo saver. Then run a linkage from there to the tail wheel. But I can’t do that without removing the hinges.

I’ve got something in mind that should work for this and will talk to it once I start to install it.

Joe

paladin

My Feedback: (9)

Well, I locked down the tail wheel for now, andinstalled the servo lead suport. I make the suport out of velumn drafting paper Because it wont absorb humidity. I rap the velumn around a broom handle then tape it so it wont unravel every six inches. Slip it off the broom and into place and glue it there. I'll post pictures later.

Joe

paladin

My Feedback: (9)

Well, I've got to decide which engine to use. I have a G-62 and a magnum 41 (USA Engines 2.5 before the evil empire bought them). While we have discused previouly that a number of you have flown this plane with magnum 41 power and it flew well. But I was not able to get a good handle on how much wt has to be added to the nose to ballance her. Will the magnum still need wt added to the nose? it looks like the G-62 will fit in the cowl, well wont hang much below it. I've started to fit both engines, initially it had looked like the slimline muffler would not fit but after a more critical review it looks like it just may. So if you can answer my questions below please chime in.

-what engine did you use for engine and how much wt did you add to the nose to ballance it?
-did you use the engine box they gave with the model?
- did you stregthen it and how?
- what are your thoughts G-62 or Magnum 41?

Joe

paladin

My Feedback: (9)

I glued the hori. stabs on last night. I did this pretty much as the plans show with a couple changes. There was a small bit of play between the aluminum tube and the run for it in the fuse. I’ve been considering shimming the play out, but I’m not sure the shims will stay in place. If I have to glue the shims, they are no longer needed. So I put a small amount of epoxy in the fuse tub (I hope I don’t end up regretting this later).

The fit between the stabs and the top of the fuse is a bit strained. I noticed that the stabs don’t fall on the fuse in the same spot. The right stab looks and fits perfect, but the left one seams to be 1/16 to high, higher than the right. After a great deal of measuring (without any of the guide marks we normally put on planes we build) I decided it was close enough that I'd have to build a jig to get accurate numbers.

Prior to gluing it all together I cut two ¼ in dowels to fit between the top and bottom stab sheeting in the opening in the stab that the servo wire ran through. I then put a pull tie around that loosely, one for each stab half. Once everything had epoxy on it I ran a pull tie between the two I added earlier and pulled it tight to hold everything together while it dries. The pull ties will stay for the life of the plane just to provide a positive lock against the stabs coming unglued. I am a bit skeptical of the length of time epoxy will stay glued to aluminum, so I’ll be watching it for signs of movement.

No pic, just don't have the time right now.

richiepingi3

Hi, I bought one of these 50cc Zeros and was trying to figure out what style of Robart Retracts will fit this plane? thanks Rich

paladin

My Feedback: (9)

Rich, I fit CJ to mine so I don’t know if there are any out there for this kit. But if I were in your shoes I’d call them. And probably spring air also. Be wary of anyone that says they will make you a set, I assume you want to fly this year.

This plane has been on the market for four years by my memory, someone must have already bought retracts for it so you just got to ask.

Joe

LDM

My Feedback: (15)

I think CJ is a good choice -Bruce does try to make gear for each plane --but its listed as such . I have the CJ gear for the CMP spitfire and the gear is made for this plane based on the length of the gear leg and retraction . Checking that this was not an Urban ledgend I looked at the demensions of the spitfire gear sold for the top flight and other spitfires and yes they are all differant

richiepingi3

I just got my 80" Zero from AK and the canopy was broken bad, I have called them and left e-mails and no one will get back to me? any suggestions. Also Joe where are you going to mount the elevator servos?

paladin

My Feedback: (9)

Rich, I'm mounting the E servos right where the plans's say.

I had a problem with one wing panel ariving with a whole through it. alex never ducked my calls or e-mails. but to get a good wing panel I had to serender the entire kit to Fedex. it took 6 weeks to get a whole kit. I wish you luck!

Joe

richiepingi3

Thanks Joe, Alex got back with me everything is ok. I'm putting a 40cc gas engine on mine hope it's a good combo?.

paladin

My Feedback: (9)

I'm looking forward to getting back to this plane. post your progress here if you like.

Joe

BOLD PILOT

My Feedback: (159)

Hi Joe,
Please keep up the great job.

pdemon

Nice work Joe
I really appreciate the needed servo torque calculation, being new to giant scale. I'm building the same model but electric powered. I'm gathering all the hardware so your thread is very useful to me.
Just a doubt: do you think the wing can be used as a two piece wing or is better to glue the halves together? I was thinking about a two piece wing and stabilizer to encase the plane in a convenient box to store and transport it.
Pierluigi

paladin

My Feedback: (9)

Pierluigi, I would love to have done it in pluggable wing and stab but I have no experience in that category and my fear of how the wing was glues together lead me to be safe rather than sorry. So I wanted to glass the center section. As for the tail I put a dowel inside the wing wedged between the top and bottom sheeting of the stabs pushed up against the ply end ribs in the middle of the opening in it. I put pull ties between those two dowels to hold the stabs on. But the metal dowel in fiberglass with vibration ment I would want some wood there so I took the easy way out and glued it.

I will be returning to this build soon, I had hoped to have something to report this weekend but I ran into a P-51D that needed a new bearing. Sounded like a john deere, bearing came apart while I was driving out the crank shaft. I have the new stainless steel ones on order and hope I can fly it this weekend at Gilbertville. We’ll see.

Joe