RE: CMP 120 Zero ARF Build thread
 

Well, for this plane it is important to have as many as you can weight in front of CG. My plane came with about 8 kg. Mostly Because it will be powered by Zenoa 26 (1.8kg) and retracts are big ones, for planes with max weight 15kg.
Glasing, panel lines, rivets and painting has added 0.4 kg.

As I can see manufacturers are making retracts in categories 5-8kg and next is 8-12or 15. I thought that putting it on maximum load is critical. With this setup I hope that I will not need any lead in front.
I have Robart tail wheel but did not manage tu put it inside. It is lite but not strong enough for this weight.

Of course we want to see all documentation that you have. Please post it. Or we have to vote? :D

RE: CMP 120 Zero ARF Build thread
 

Elevator assembly

On movable surfaces of elevator, I made little ​​tray in balsa for wire that will move
it. Tape will prevent excess of epoxy glue to get on cover.


http://img847.imageshack.us/img847/1898/dscn2287a.jpg

A little glue, and wire is inserted

http://img195.imageshack.us/img195/1729/dscn2288i.jpg

Linkage is with bovden's, each half has servo. Servos are classical analog.
In this picture ends of the bovden's are not glued yet, but as my little son said
"In real life, they are"

http://img843.imageshack.us/img843/1068/dscn2289v.jpg

Still remain to solve chock (hopefully tomorrow) and then weathering.

Hire is working atmosphere at the dining table.

http://img853.imageshack.us/img853/1241/dscn2292.jpg

RE: CMP 120 Zero ARF Build thread
 

Im running electric retracts for the mains and was considering your set up but it would have to be converted with a lado actuator any thoughts how or even if this is a possibility?

RE: CMP 120 Zero ARF Build thread
 

Yea, you could just use a standard servo. Since I've added the lever that acts as a down lock, no stress would be on the servo. I don't know how the lado's work, so I can't advise on that.

RE: CMP 120 Zero ARF Build thread
 

You have got to be kidding, your plane weighs more than 17 1/2lbs?! Heavy finish, need heavy stronger gear, have heavy finish and heavy gear need bigger heavy engine! Let us know how that flies please! Dave Platt's 1/5 Zero came in at 14lbs and it had a .90 two stroke!

I here all of you, wanting to see the tail wheel build, so I shall proceed with aforementioned instructions. I will be flying tomorrow, I found someone to hold my hand and to make sure I don't hurt myself when I play with my toys (we must fly with a buddy at our field), I'm going to recommend that everyone in our club must where a harness at the field.
You all have a good weekend.

RE: CMP 120 Zero ARF Build thread
 

As I said, the plane normal to the weighing about 6 kg.
When you add retracts (300g), strengthening the wings mounts for retracts (xxx g),
the engine (at least 800 g heavier), glassing and painting (400g), additional sevos (total 10) 3s lithium battery, voltage regulator.

There is nothing special in this plane. Hope tomorrow will be able to finally put it on scale so you will all now verdict.

RE: CMP 120 Zero ARF Build thread
 

Misha i wouldn't worry to much about total weight there have been reports on this thread of this plane ending up at the same weight range and those same reports say it fly beautifully! I expect mine to come pretty close to that as well

RE: CMP 120 Zero ARF Build thread
 

Anything will fly with enough power, and probably fly well, BUT when the engine quits is the question. I can't see it having any kind of glide at 17 lbs. I want mine to be a good Sunday flyer, so I am going to do my best to keep this thing as light as possible.

ARF's have limitations, one thing I don't like is the two piece stab with the 1oz of aluminum back there. A one piece stab would be the best, but I'm not going to put that much work into this, might as well build a new fuselage if I do that!

Good luck, I will keep track of my weight as I go to see how it adds up, right now with engine and some servo's I'm at 6.9lbs, but if it turns into a brick I'll get rid of it.

RE: CMP 120 Zero ARF Build thread
 

11 to 12 lbs is what cmp calls for on this plane and I've yet to see anyone come even close to that you should expect closer to 14 would be a practical number and yes 17 is in the high side but I've seen stranger things lol

RE: CMP 120 Zero ARF Build thread
 

I don't wan to get anyone mad here,I just panicked when I saw the nearly 18lbs ready to fly. So to each his own, I was just really hoping I could get it near 12 or on the high side 13lbs, we shall see. But that was a wake up call for me, I'm going with ultra light weight covering and CA hinges! :)

As you did with yours ZERO-322, I got some Hitec HS-77BB Low Profile servo's for the elevator and rudder. Mounted on the sides of the fuse, they will hide well under the pilots console. For pushrods I went with Sullivan #585 White/Black Carbon Fiber so that I could use all those little holes in the fuselage formers. I also added a wire rod with one control lever for the elevator. The hole for the former in the rudder post was a perfect match. I am keeping everything in front of the CG as much as possible. I got lots of flying in today, so I did not finish the installation, I still have to hook up the steering cables for the tail wheel. I also received my steel powder nose weight, so I will be casting a dummy radial as nose weight, let's hope I don't need 3lbs!:D

RE: CMP 120 Zero ARF Build thread
 

My Zero AUW is 17.2~17.5Lbs mainly due to scratch built strong wing and fuselage repairs after crash.
(CG 135~140mm at the root, sure little tail heavy)
Today I flew few times and my wife took some video by new camera I bought.
It was first time today for her use this camera (Canon powershot SX130) so sorry for not catching up the speed...
I think 17.5Lbs CMP zero 71" flies pretty good but landing is little challenge everytime to not to damage retracts..
I got dead stick few weeks ago with this 17.5Lbs zero and luckly came back to ground with no issue. (Of course I was very nervous and just tried not to pull elevator at all until wheels touch to the ground).

These are the videos I uploaded today.
http://www.youtube.com/watch?v=q20Gz5WJf0M
http://www.youtube.com/watch?v=Vm7AH5F0Icw
http://www.youtube.com/watch?v=rQO3U8OD6Pg

RE: CMP 120 Zero ARF Build thread
 

Glad to hear that i am not alone with this weight. Thank you for sharing those videos with us.
On video, it seems very fast on landing even with flaps..

One thing I didn't understand. Where is your CG if at 135-140 is tail heavy?
And the other question is control throws. Are they like recommended in user manual?

RE: CMP 120 Zero ARF Build thread
 

I think best CG is 125mm at the root. (I flew with lots of down trim on that video)
Landing speed is due to heavy weight. All planes lighter is better and easier to fly...
Control throw- Aileron 20mm up 20mm down, Elevator 15mm up 15mm down, Rudder 25mm left & right.
I didn't refer instruction at all.

RE: CMP 120 Zero ARF Build thread
 

Super. Will tray tomorrow and see where Cg is at this time on my Zero. My good friend Mirce who has helped me with glassing and painting, (and he is flying big warbirds)
is always saying that weight is not important and that, the bigger and heavier plane is, it flays more realistic and easyer

thank you for data.

RE: CMP 120 Zero ARF Build thread
 

I've been flying mine more now that I have retracts that work. Mine weights 15 lbs 14 oz with the tank empty. I tried to build it as light as I could and still build stronger gear mounts and add flaps. No glassing, except in the gear area, only repainted the bottom. No retractable tail wheel or cockpit. Built it more to fly and not for "Scale Masters". But I can see that other planes on this thread are truely works of art and can compete with the very best scale planes out there. I test flew at 135mm cg and was tail heavy. Now its 120mm cg at the root and flys good. Diffenently not nose heavy. Powered with a 25cc conversion which is adequate but not over powered. Flys scale. I would not recommend a test flight with the cg further back than 135mm, but maybe I just don't like overly pitch sensitive airplanes.

RE: CMP 120 Zero ARF Build thread
 

Bean thanks for the insight


i had mine set at 135 prior to all the recent changes and additions full cockpit and full pilot sliding canopy split flaps and scale exhaust and dle 30 engine not to mention strengthening the gear mounts and glassing the wing etc which all will add weight just hope its where its needed most but i do expect mine much like Misha to tip the scale close to 16 and half if not 17 lbs so i will heed your advise and set it at 130 mm as a starting point and work from there


thanks again for the flight report!

RE: CMP 120 Zero ARF Build thread
 

There is some truth to that statement, but the first part about weight not being important is incorrect. Bigger planes generally speaking are heavier, a heavier plane with more wing area and extra weight will handle wind better and fly smoother with much less pilot ability. But, and this is the but, if you load up a smaller plane to be as heavy as a much larger plane you are asking for trouble. I think the reason these planes fly so well is because of the basic design of the Zero itself, if CMP could have made a lighter plane, say with a built up fuselage, I think it would be outstanding. I believe that in calm conditions any plane can be flown smoothly and realistically, no matter how light.



MrBean, you make me laugh! lol!:D

Well folks, for your masking pleasure I offer the Zero canopy! Actually I am not offering this for sale, I only had one person ask and I only made 1 extra, it will be for L16pilot.

I saved 3oz in the wing by adding bellcranks and one servo, it should come out to more savings in nose weight. My single flap servo will be mounted in the old retract servo slot in the leading edge of the wing.

RE: CMP 120 Zero ARF Build thread
 

Zero 322, need some help on my retracts for the WM zero 60. Got hitec retract servo and it burned out before the maiden. Should i just lock it manually and never use retracts or should i go for the JR 791's<div>
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RE: CMP 120 Zero ARF Build thread
 

I used the JR's in my H9 Hellcat and I had 2 of them go bad on me, a total waste of money. For smaller planes they might be fine, but for longer heavier gear retract servo's are no good.



I just got off the phone with Dave Platt, I didn't bother telling him who I was and that I used to go to their club meetings and talked about his designs and scale models a few times when I lived in Florida. Anyway, he would not sell me a Zero cowl or any parts at all, he only sells semi-kits, that is all he kept saying. So if you damage a canopy or cowl of a Dave Platt model you have to buy the entire semi-kit to get your part! This could be really bad if you buy a second hand Dave Platt model and it needs parts. Sooooo, what to do? :D

RE: CMP 120 Zero ARF Build thread
 

If you decide to make some more, I would buy one.

RE: CMP 120 Zero ARF Build thread
 

What he said! Hell you could put me down for the tail wheel as well i would happily purchase both!

By the way i got those cockpit parts together for you ill get them in the mail in the next couple of days and send you an e-mail, life has been really hectic with work and family i haven't had much time for anything rc wise, but hopefully soon

RE: CMP 120 Zero ARF Build thread
 

for This bird i opted for electric retracts by lado never had a problem and never looked back, you could try the Jr but both manual and air retract are more trouble some by design both set up and overall maintenance
my suggestion is you check out www.magnumrc.com look under retract also you could check k out www.downandlocked.com for there electric set ups and cost and go from there

good luck in what ever you decide


Mike

RE: CMP 120 Zero ARF Build thread
 

Luke - Thanks much...I will post pics when I receive the canopy and document the installation. I hope I do you and your canopy proud.

RE: CMP 120 Zero ARF Build thread
 

After colision with FW 190 (my son and his soccer ball)
I had to repeint part of the wing size of 5x5mm.

http://img560.imageshack.us/img560/7770/dscn2351.jpg

Since I started painting, I thought that I could paint a few small things.

http://img821.imageshack.us/img821/7600/dscn2352j.jpg

This white plastic is the upper part for securing 4 screws for aileron horn.

http://img11.imageshack.us/img11/7524/dscn2353d.jpg

http://img542.imageshack.us/img542/3530/dscn2360.jpg

now it is looking much better

As for the Thunderbolt, I have printed label with the details of cocpit and cabin areas,
and instrument panel in front of the pilot.
After I trim plane, and if it can take some more weight, I will make sliding canopy and
details in cocpit with parts that Mike send to me.

http://img19.imageshack.us/img19/5502/dscn2340w.jpg

http://img59.imageshack.us/img59/89/dscn2354n.jpg

http://img848.imageshack.us/img848/2898/dscn2356.jpg

The rest of the cabin I painted over with black paint and then did a little sending to
get a visual impression of several uears of usage

http://img233.imageshack.us/img233/9281/dscn2339.jpg

http://img541.imageshack.us/img541/3843/dscn2357d.jpg

http://img3.imageshack.us/img3/8863/dscn2359y.jpg

I've already started I move the paint, brushes, solvents and catalysts when I remembered that I could paint the screws
used for attaching canopy, as well as those for the rear wheel cowl.
On top side screws will be dark green color and on the bottom a light gray green..

http://img853.imageshack.us/img853/2286/dscn2349c.jpg

http://img707.imageshack.us/img707/5603/dscn2350m.jpg

...

RE: CMP 120 Zero ARF Build thread
 

I dont think its an arguement just good discussion, but on the issues of weight I hve found one simple pemise and I think that it was said years ago by a very wise man .The statement must have had much more meaning to those who truley knew avation when it was stated "we dont build them to survive a crash , we build them to fly" .
When I started with warbirds every possible piece of advice came at me on how difficult they were to fly, do this , do that , use rudder, fly only on sunny days with wind in your hair ect ect ect.
So as you can imagine I was nervous until I found one simple consistant element that defined (for me ) the level of difficulty of any warbird I have flown with the exception of Jets .
That one single element was "wing loading" and the one simple formula regadless of what plane , what airfoil , what urban legend mostly created on RCU , the lighter the wing loading the easier the plane was to fly , it was that simple. The only other factor ever to enter into the simple uncomplicated world of flying warbirds was -washout and for the most unless poorly designed (Top Flight Gold Edition P40 Kit ) , I never needed to worry about washout , because it was typically done correctly at the factory or plan stage .
'So remoeving all the facts and unknowns on "can a CMP plane withstand an 18 pound flying weight " the fact that has held up for me has been -keep it light and it flys right !!! Its that simple .
If you want to see why there is a incredible craze on simple 55" thru 65" EPO foam warbirds , simply try one and you will see that it looks like a warbird , its sounds like one , it has retracts , flaps and many bells and whistles but it flys like a trainer , why ? all because of wing loading !!!!:D
Enjoy the Zeros , great mods so far keep them going !!!