CMP SUPER CHIPMUNK 120
 

Anyone have experience with it? looks very nice, I was wondering as I am unable to find much info on it.

RE: CMP SUPER CHIPMUNK 120
 

I have one in a box in the closet, looks good, will have a Saito 125 in the pointy end when I build it.

RE: CMP SUPER CHIPMUNK 120
 

Have the smaller 40 size from CMP it is an alright plane. I did not care for the motor locations not being marked or a template or something. Did not care for the hardware for the elev. and rudd. asume it will be the same. Wooden dowls you must drill and mount metal rods to. Nothing prebent. Need to have a bender for sure. I like the fiberglass fuse. Hate the landing gear. Might as well beef it up or at least put a good coat of epoxy werever the rod sits and cover it in a layer pretty thick or it will rip the wings were it mounts out and do a good bit of damage. The Motor area you will also have to set your thrust deg. Very good looking plane and flys pretty good lands a little hot but overall pretty plane. Just some stuff i went thru with the smaller version.

RE: CMP SUPER CHIPMUNK 120
 

I have the wings, landing gear. control surfaces and stabilizers completed on mine. Have a gms 120 going in it. Im very happy with it so far. I used dubro hinges instead of the ca ones. The only thing at this point that I didn’t like is the tail wheel set up. I kinda did my own thing here. I will take some pics of my mod and post soon. I read in here where a guy said his landing gear gave out on landing. Im not going to tear into it to reinforce it now, just wait and see how she does. Oh and I pilled the black pin stripe off down the fuse it wasn’t sticking very well and I don’t think it looks any diff without it. I love the fiber glass fuse, its light, strong and very roomy. Ill take some pics of my progress and keep it posted.

RE: CMP SUPER CHIPMUNK 120
 

Not always a good assumption... the larger planes often include better hardware, even if it is only slightly so...

You can use at least SOME of the hardware on the larger planes...

RE: CMP SUPER CHIPMUNK 120
 

Thanks, I'd appreciate photos of your assembly process.

Is the nose set up for a 2 stroke engine with a conventional silencer? from what I have been able to see there is a "cutout" at the fuse bottom to allow this? I'd appreciate a photo of that area too.

RE: CMP SUPER CHIPMUNK 120
 

Sorry I haven’t had time to post pics yet. Yes there is a space underneath the nose for the muffler on a 2 stroke, I will try and get some pics up tonight. My engine has been on the test stand ever since iv had this plane so I haven’t had a chance to see if the cavity for the muffler is big enough for the muffler on my gms. It looks like it will be close if not then I will have to do some moding. You can see the muffler cavity in this pic.

RE: CMP SUPER CHIPMUNK 120
 

Ok. So far I have glued wing halves, and fasteners to bolt wing to fuse, installed all control surfaces using du-bro hinges, installed aileron servos, landing gear, wheels and pants, both stabilizers and tail wheel assembly. I will only point out the things that were non standard in the assembly so far as opposed to easier arfs with better instructions. Everything else was normal. All of these mods u can see in the pics. The first thing I deviated from the instructions is installing a nylon landing gear strap on the wooden piece that attaches vertically along each gear wire. The instructions just stated to epoxy these but I wanted the extra security. Next, the kit was only supplied with one wheel collar per wheel for the outside of the axle. I cant see how this would have worked as the inside of the wheel would have rubbed agents the wheel pant without some sort of spacer on the axle, in this case I installed another wheel collar on the inside, see pic. The tail wheel assembly has been the most incontinent. Its hard to describe so I made 2 diagrams. The instruction just stated to run the wire up through the fuse and bend 90* to be epoxied to the rudder “that’s all”. Ok u can see in the diagram how I did this. I cut the wire to length, added a collar and washer under the fuse to take the load off the rudder, attached a steering rod to the rudder so the tail gear wire could just slide up through it and be held by the set screw in the steering rod. I added some fender washers to the wing bolts, that will get painted later. I usually do this with kits that come with rinky dink washers, just gives more surface area for the pressure the bolts will apply. The wing joiners and holes where not pre drilled so lining these up for proper fit took some time. I drilled out the holes in the LE of wing where joiners would go and laved down a wooden pencil x 2 cut just long enough to barley protrude form the wing. So when I seated the wing the pencils would mark the fuse side. With a little bit of luck and patience this got me close enough to drill the second set of holes for the fuse. That’s it for now. I’m am building this arf slow but I will keep the post updated and pics as I progress. Thanks Tony

RE: CMP SUPER CHIPMUNK 120
 

here is the pics......... sorry

RE: CMP SUPER CHIPMUNK 120
 

Thanks tonywayne! these photos are excellent!

Your idea with the tailwheel is brilliant - I see use for it on other models with a similar tail design.

I have an option to get this ARF but wanted some idea about it beforehand.
My only experience with CMP is with their large P-51 with which I was very happy, especially with the very low weight.

I have a spare, low time, reliable ASP 1.08 two stroke I was considering for this model.
It swings a 16-6 or 15-8 very well, and also it has a rather small silencer (for a 1.08) that I was hoping would fit inside the front cavity.
Is that cavity designed for an engine mounted at 45 deg below the horizon?
I'd appreciate some views of that area when you get the engine in place, but I think I will seriously consider getting this one.

I also noticed the model features flaps? other photos and ads for this model did not mention them so I'm happy to see they are there.

RE: CMP SUPER CHIPMUNK 120
 

I put togeather one of these beautifull birds last year but havn't flown it yet. I have a ST G90 in the nose. A couple problems with the ARF are
(1) the landing gear blocks in the wings both came unglued when I inserted the landing gear in. Better on assembly rather than landing. I cut into the wing from the top directly above the blocks and found that there was next to no glue holding the landing gear tourque blocks or the grooved block in place. This would have been disasterous on my first landing. I reglued everything on both sides with Epoxy.... nice and strong now.Then I just widened the Black covering to cover the repair access hole.
(2) I also did not like how the tailwheel attached so I installed an extra servo on the bottom of the fuse and Y harnessed it to the rudder servo. I used shock absorbing steering likages on both sides of the servo arm and it works like a charm and a simple install.
(3) The cowl also fits like crap so just do the best you can with it.

Curt

RE: CMP SUPER CHIPMUNK 120
 

EF, your Q about how the engine mounts, I don’t know about a 45 deg but it will mount where the center line of the muffler will be striate down form the centerline of the fuse. So the engine will be at an angle below the horizon but not much. Here is a sketch for that. I’m sure the muffler on your asp will fit inside the cavity. The muffler on my gms 120 is huge and I believe it will fit but if it doesn’t it will be close. Sourkraut’s tail wheel method is a very good idea to. I honestly didn’t think of that if I had a spare servo I would have considered it. About the weak landing gear, I read in another post someone else having the same problem with this kit accept he discovered it on landing’” . Now that I have heard about this from 2 sources I am considering reinforcing this area before the maiden. Going in through the top and recovering with black sounds ok. Thanks Sourkraut. What size servos did you use? I used standard for the ailerons and flap, and high torque for rudder and elevator like 75 or 90 oz in.

RE: CMP SUPER CHIPMUNK 120
 

Hi Tony...I will try and get some pics for you of the spots where I cut into the wing top balsa and how I covered it later today when I get home. I cut a piece of balsa out directly above the wing gear blocks from rib to rib and about 1.5" wide(big enough so I could get in there and reattach and reinforce everything. Even if your tourque blocks feel solid see if you can remove them and reattach them with epoxy. Mine were only held in place with a drop of CA. This is a "must do" repair before you fly or you will have a big repair to the wing in the near future if you don't!! To nice a bird to have it destryed because of this. I will also take some good pics of my tailwheel setup for you guys to look at and you can let me know what you think. I used standard Hitec 425BB's all around, 325BB's for throttle, flaps and steering. I use these servos on all my birds with no trouble.

Curt

RE: CMP SUPER CHIPMUNK 120
 

Tony... here are a few pics of the wing and the tailwheel assy. Hope this helps

Curt

RE: CMP SUPER CHIPMUNK 120
 

Thanks for the pics. I picked up some black monokote today for the wing. I will just cut as small a hole has possible to allow me to get some epoxy around in there depending on how poorly glued it is I will cut more if needed. I need to get a servo saver for my rudder or make one if I can find some small springs. Know or seen a way to make a improvised servo saver?

RE: CMP SUPER CHIPMUNK 120
 

Yeah, start off small and widen if you have to. I opened mine up a fair bit because I wanted to make sure it was glued good.
Those little servo saver springs are hard to find, I just bought the DuBro setups and used them.
How does your cowl fit and lineup?? Mine didn't fit that snug, kind of sloppy.

Curt

RE: CMP SUPER CHIPMUNK 120
 

Tony, please post lot of pics as you go along...

thanks,
V.

RE: CMP SUPER CHIPMUNK 120
 

The cowl fits pretty much like it shows in all pics even the ones on there website, If your talking about the gaps between the cowl and the fuse I don’t mind that so much. The instructions show adding a small block of plywood between the cowl and top of fuse for spacing, maybe this is to allow for airflow. I haven’t installed the engine or done any cutting to the cowl yet but that will be my next project tomorrow if I get to it.

RE: CMP SUPER CHIPMUNK 120
 

Yeah, I added a small rubber shim between the cowl and the top of the fuse to hold the correct height and shape. It fits OK just not as precise as some other brands of Chippies. I really do like the looks of this bird however. Now, as long as it doesn't fly like a brick like the CMPro Yak 54 does.
I hope to get mine maidened within the next 2 weeks. Hopefully I'll have a glowing report.

Curt

RE: CMP SUPER CHIPMUNK 120
 

Like a brick! What size engine was in the Yak? It has about the same dimensions as the chip. Im thinking my GMS 120 should pull it around pretty good. Right now its turning a 16x6 prop a little over 10,000 rpm.

RE: CMP SUPER CHIPMUNK 120
 

Sorry I haven’t had the time for my chipy lately. Sourkraut have you made your maiden yet? Would love a report. Well I finally got the cowl shimmed up and installed. I took some pics and will describe a little what I did. The only real problem I ran into is the huge muffler on my GMS 120 barely touches the fuselage in the muffler cavity. So I will atv some ceramic cloth here to protect it form melting. You can see I added a shim on top for the space between the cowl and the fuse. I used a piece of wooden cloths pin for this. Other than the cutting for the head I also had to cut away the cowl for part of the carb. It also allows for easy adjustment of the low speed. I also widened the intake vents opening more just to allow for more airflow. As far as the fasteners I used more than the 3 that the kit comes with. One threw the spacer on top, another forward of that threw the top of the firewall and two on each side threw the fuse. I plan on using a fuel filler valve to keep things clean and simple there. Over all the process was a simple task thanks to the dremel and proper tools. The cowl seems to be a little over sized but I like the idea that this allows for better air flow past the engine. Because im using a perry pump I am able to mount the tank nearly on the CG up agents the servo tray. This made for the servo pushrod rout a lot more strate forward. That’s it for now. All that is left is the rest of my radio gear, pushrods and canopy. And a little more fuel proofing here and ther.

RE: CMP SUPER CHIPMUNK 120
 

Sorry forgot the pics agen. Here they are.

RE: CMP SUPER CHIPMUNK 120
 

Sorry I haven’t had the time for my chipy lately. Sourkraut have you made your maiden yet? Would love a report. Well I finally got the cowl shimmed up and installed. I took some pics and will describe a little what I did. The only real problem I ran into is the huge muffler on my GMS 120 barely touches the fuselage in the muffler cavity. So I will atv some ceramic cloth here to protect it form melting. You can see I added a shim on top for the space between the cowl and the fuse. I used a piece of wooden cloths pin for this. Other than the cutting for the head I also had to cut away the cowl for part of the carb. It also allows for easy adjustment of the low speed. I also widened the intake vents opening more just to allow for more airflow. As far as the fasteners I used more than the 3 that the kit comes with. One threw the spacer on top, another forward of that threw the top of the firewall and two on each side threw the fuse. I plan on using a fuel filler valve to keep things clean and simple there. Over all the process was a simple task thanks to the dremel and proper tools. The cowl seems to be a little over sized but I like the idea that this allows for better air flow past the engine. Because im using a perry pump I am able to mount the tank nearly on the CG up agents the servo tray. This made for the servo pushrod rout a lot more strait forward. That’s it for now. All that is left is the rest of my radio gear, pushrods and canopy. And a little more fuel proofing here and there.

RE: CMP SUPER CHIPMUNK 120
 

RCU craped out on me the first time. said it timed out, thought i had to post it agen. sorry for that.

RE: CMP SUPER CHIPMUNK 120
 

My AUW was about 10.5 lbs. I had to add 8oz of lead to the tail to get the CG where the manual says. My first maiden was not a pleasant one. Right after take off it felt way tell heavy. The GMS 120 had plenty of power but it flew like it was pulling a brick and the elevator was very sensitive. My landing was almost tragic. It tip stalled right when i started to flare out for landing about 5' off the ground and came down pretty hard. I wasn’t going that slow. It only scuffed the wing tips and badly bent the gear. Luckily a friend was videoing. You can tell by the way it takes off it looks tail heavy. And coming in for landing what looks like bad piloting skills is just me fighting the very sensitive elevator. My rates were set very low so I know I wasn’t over correcting. I have been flying for 14 years and never had to fight an unbalanced plane like this. So now I am in the process of shedding some weight. I have cut allot of fiberglass off the cowl and under it and off the fuselage under the canopy, about 4-5 oz worth. It is still strong and still looks ok. I have also replaced the aluminum motor mount with the stock ones, that saved me 3 oz. I am cutting the muffler shorter on my gms. I’m running a pump so I don’t need it for pressure anyway. If i can lose the lead in the tail I should drop at least a pound or more. My CG was about 5’’ the manual says 4.6-4.9 I will balance it at about 4.5 before my next attempt. Here is a link to the video, watch closely how the tail drops right after take off and how the wing dropped right when i started to flare out for landing. http://www.youtube.com/watch?v=SZDN_tbUy_s