acontreras

I recently bought a CMP Corsair 120 which I will power with a Saito 125, landing gear is Century.

I am looking for all your tips and various lessons learned to help me speed the assembly along.

I notice that the Century retracts are (clearly) not a simple drop in affair. I'd be interested in knowing how you or somone you know modified the wing to accept them.

Also, the instructions are silent on the CG placement (or maybe it was in Chinses somewhere!)

Thanks,

Antonio
Havelock, NC

Tinknocker

Antonio: I am currently working on the same setup. Had to do some cutting on the fiberglass to get mine to fit. Also had to make 3/4" blocks to mount the gaer to and on the side where the airline comes off I used a 3/4" long aluminum spacer. I drilled and tapped the blocks and used a blind nut on the srew with the spacer.

Tinknocker

Antonio: Forgot about the CG I emailed CMP and they said the CG range is 90-105 mm. Read through they instructions about 10 times trying to find it.

Jim

acontreras

Thanks. I think your pictures are fooling me: did you take the air cylinders/pistons off the retracts and fit them through the existing holes in the wing, or did you cut through the spars and then rebuild the spars with "scrap" plywood?

Antonio

Tinknocker

Antonio:
No I didn't take the cylinders apart, but I did reinforce the spar on each side because I had to enlarge the hole through it to get the cylinders through. I also had to widen and lengthen the opening in the fiberglass on the wing. As for reinforcing the spar it may not have been necessary but I just wanted to be sure.


Jim

Tinknocker

Her are a couple of closeups

acontreras

That's what i thought.

I see you went with the single servo flap retract. I'm concerned that to keep the flaps up, there is a significant amount of force required. Did you do any mods there? What servo are you using for retracts?

Thanks for the CG too.

I was thinking about maybe putting in a built up cockpit: http://www.vikingcockpits.com/Product%20Catalogue.htm Has anyone tried that?

Antonio

Tinknocker

Antonio
I used Futaba 3003 for the retracts and the flaps. The control block for the retracts is mounted to 1/4" plywood CA'd to the top of the servo, since the connection was so short I soldered a piece of pull pull wire to a 2-56 threaded rod to keep it from pulling the slide sideways and pinching the "o" ring. The flaps seem to work fine with the standard servo.
I left the tubes for the cables as long as possible.

Jim

kahloq

Hmmm..... not sure whether to go with this one or H9. I like the idea of flaps on the plane, but there is little information on the flying performance of the CMP Corsair

LDM

My Feedback: (15)

Just a few friendly suggestions on retract instalation , there is no such thing as"drop in " I know after speaking with robart they will actually try to make some after market "drops in for H9 planes but almost every install requires mods .
My own method simialr to the above excellant work done by jim is adding one more step . I usually glass or use flight skin on the inside base sheeting that will act as a very strong foundation . If I add rails for the retracts , I have the rails go from bottom wing sheeting to top forming one solid piece , then i exposy the entire structure . YOu can dremil out the area you need to custom fit the retracts as far as width .

As far as H9 corsair vs CMP , I have the h9 and love the plane , however for the money I feel CMP is a better buy giving you a larger plane , flaps and thicker tail area .

kahloq

For the money, the CMP does not include retracts. I also do not have a motor sufficient to fly it I dont think. I have a Saito 100 and a Saito 125. The 125 is slated for my KMP ME-109.
Do you think a Saito 100 can fly this plane? Its actually slightly bigger then the ME-109
Now, the ME-109 can be flown using the 100 since it was tested with an rcv91 @1.5HP and the saito 100 is 1.8HP. But, the reason to have some of these planes it to make nice fast approaches and have adequate power. The 125 was bought since it has 2.2HP.

carlbecker

My Feedback: (3)

You would be better served if you used the 100 in the Me 109 and the 125 in the corsair. You may not have to add lead to the nose of either if you are careful. IMHO using HP figures for comparison from different manufactures will not give good results. From what I have seen at our field the Laser 120 is about the same as the Saito 100.

Carl

I left out some of the rest of my thought.

I have used the Laser 120 in a CMP 70" Zero at 11 pounds and it flew very well. I believe I have read here about the KMP Me109 using the Laser with good results.

RAMFlyer

My Feedback: (65)

Finally got some flying on this bird last weekend. Bought it from AK Models late last year but didn't get it done until recently. It flies great!!! I built it stock but did put a flap servo on each side of the wing. Winds were 15--25 mph and crosswind on Sunday and it handled it fine.

I used an old Zenoah G23 and had no need to add weight for balance. That also allowed me to get the tank back closer to the CG. I put this one together with the idea that if it flew well I would get another and trick it out with retracts, cockpit, and different markings. I will definately be getting another one!!!

This thread also has some good info for you:

http://www.rcuniverse.com/forum/m_5138604/tm.htm

kahloq

Well, I think Im in a bind then. I wasnt happy really with speed of saito 100 on 14x7x3 or even 14x8 2-blade on a H9 Spitfire....granted...its a rather new motor, with about 1 1/2 gal ran through it. Hence the reason for the 125 for the ME-109. I may just have to do the H9 F4U instead since I dont want to have to buy yet another motor.

acontreras

Where do I start??

Engine: 125 is a must in my mind. Have I tried a 100? No, but I feel this airplane needs all it can get, and the 125 delivers. Even with that engine, it flies scale (no warp speed for me), 15x6 prop.

Flight performance: <borat> yes! I like! </borat> I've recently come back from deployment, so my thumbs were a tad rusty. a few weeks getting my thumbs back on the PTS and Texan, and I had no issues flying this plane. In fact, I was surprised to find myself more comfortable with the Corsair than with the Texan, so go figure.

Dry weight is right around 14 pounds (scale is not very exact), but that's after adding a tad over 1lb of lead in the nose right above the engine, and with a heavy hub... This baby is very tail heavy.

Century retracts... Not my best experience, they bent on my first couple of landings (the first one was textbook, the second wasn't bad at all, yet they bent like noodles). I have a repair order in with Century, they will take a look at them as soon as I get around to mailing them. So, hopefully some good customer service will take care of what has started as a disappointing experience. Ah, do get a 4 way valve, the standard valve goes too fast.

Flaps: used dual flaps, ditch the wire system. I used the 125MG for the rudder instead, and ST47BB for the flaps. Also, the seemingly flimsy tail wheel and wire work just fine once the plane is moving, no need to beef up.

Questions?

Antonio

carlbecker

My Feedback: (3)

I would use the Saito 125 in the Corsair without hesitation. In my experience using more pitch can really change/help flight characteristics. I would try a 15x8 APC if you want more speed. IMHO they are efficient and help balance a tail heavy plane. I don’t think 3 blade props on small to medium engines is efficient. I don't usually over power my planes a lot and prefer scale like flight. I have flown some of my planes with less power causing me to get her down before I lose her kind of flight.

kahloq

Using the 125 I have in a CMP corsair would relegate the 100 I have to the KMP ME-109. I dont like that scenario much. With a 73" wingspan, the Me-109 will need a decent motor(aka 125) to give it the oomph it needs for good speed. Sure it'll fly on the 100, but wont be very fast at all, no matter what prop is used.
I'd love to get the CMP corsair, but having to buy another motor doesnt really appeal to me right now. plus, I'd also have to buy retracts. I have some rather large mechanical 90 degree rotating, but, not sure if they're the right size for this plane.

elvir

Hello, I just wanted to know if any one has had a problem with the center section of the wing form the cmp corsair 120. I have a g 20 in it with a grupner 16x8 3 blade, when I can get into the air it fly’s grate, plenty of power. Problems with the retracts turning to the side on take off and landing and doing a flip So now the fiberglass center section is loose from the wood support in it and the wing has a bit of movement up and down , has anyone has this problem or done anything for it , I was planning to take the bottom fiberglass section off the wing in section and fiberglass the wood so it dose not move. any suggestions before I hack it up?

elvir.

LDM

My Feedback: (15)

Does this plane have sheeted wings , I cant tell from the pics ?

vasek

My Feedback: (4)

yeah full sheeted except the chamfered tips

whatwheel

I have a cmp corsair still in the box, dont remenber when I got it , 3 or 4 yrs. back. I keep hearing about the improved kits, I have heard about colors not matching,and wing center sections with weak wood inside. Now the one I have is the 120 , have not seen any wood in center section { could not get a good look} my wings are wood sheeted foam, all blue colors match.

Have Igot myself a dud or what?

Thanks for any replys,
Glenn.


p.s. I also have the 120 zero and 140 mustang.