Hello,

I am just beginning the assembly of my KMP Beaver. I'm posting here in the hopes of acquiring some tips and tricks from those that have this plane. I've read the main post regarding this plane, but it's mostly unrelated to my very early assembly stage. So, I'm looking for suggestions from the group in the way of modifications, reenforcements, etc. at the earliest stages.

I think that the ARF looks pretty good, although there are some aspects that could use improvement. I think that some of the formers look like they could be better attached to the fiberglass fuse. Anyone add glass or epoxy to these junctions? Anyone add additonal formers to stiffen the glass fuse?

I also think that the stock linkages for the control surfaces at the tail could be done better. Is anyone using a pull-pull on the rudder?

Anyway, as I mentioned, I've only unpacked the plane and not yet really started.

Any feedback on the assembly would be greatly appreciated.

Thanks.

Noah

would like to here more about this plane also what motor are you thinking about useing. I would like to go gas G26. Rich

Butlern: Good moorning, I have a Kmp Beaver flying now, it is my first big plane and I like it,
but yes it does need some mods

This is what I did:

1 Got rid of the 2 servos and stock water rudder ( too heavy) and installed a Ernst rudder and a pull pull system using the rudder servo.
The access hatch was eliminated and painted the floats: Water would come in even if I put
silicone on the hatch cover.

2. All hardware, screws, clevis were gone. Bad quality.

3. Inside the fuse where the aluminum tube goes in and the former were reinforced, the firewall was also reinforced.


4. And the most important was to correct the position of the step of the float, originally was 3 inches behind the cg, end up at 1 inch behind the cg, and the wing incidence was 8 degrees so I fix it and made it 2 degrees. Also got rid of that cheap landing gear and struts and made new with some aluminum bars I bought on a web site. By doing so I notice the floats were 18 inches appart and the rule tells you they should be 25 percent of the wingspan, so 24 inches apart, so I dit it that way.

5 The wing strut goes attach to the wing by a regular screw. I put a blind nut in there ( on the wing) and replace the screw. I did this to make the wing and strut stronger, once came off
on flight.


If you have any question feel free to ask, and hope it helps
Sincerely

Morromaxx

Morromaxx,

Thanks for the reply. This is exactly the type of information that I'm currently seeking.

Would you be willing to share some pictures of your Ernst water rudder and pull-pull set-up? Also, your newly fabricated gear/struts sound interesting. I'd like to see those, too, so I can get an idea of how exactly you proceeded with those modifications.

Rich,

I have a ZDZ 40 on the way. I'm collaborating on this Beaver with another club member, and he was responsible for power-plant selection. Throttle management, yes indeed. I think that your G26 will do the trick. Other posts have indicated that the G26 provides adequate power for the Beaver with floats.

Morromaxx, what are you using for power?

Thanks.

Noah

Butlern: Ok I have tried sending pictures through RC universe and it has been quite difficult for me, maybe I´m doing something wrong. But if you send me your private e mail I will do so gladly.

My e mail is [email protected]. Write there so I get it please

I am using a Brison 40 engine, Very happy with that choice. Plenty power.

Thanks

Morromaxx

I am just about finished with the Beaver. Thanks to Morromaxx et al for the feedback, and to AKflyer and PaulGC for comments in an earlier thread.

Just one more thing before I put it up in the air... is the CG at 80mm appropriate, or have some of you (akflyer, PaulG-RC) modified this for better flight? Once I set this I'll be ready for wheeled flight, then on to the floats.

As most of you have, I set the wing-float incidence at 2.5 degrees by remaking the float struts from flat-stock aluminum bar. I also placed the step just behind (1.5cm) the CG (at 80mm, hopefully that CG value holds or I'll have to rework the float struts a bit more). Lastly, I remade the wire gear so I could spin a bigger prop (using a ZDZ 40, and I determined that a 20" prop would scrape when the tail lifts on take-off if I used the stock wire gear).

Looking forward to hearing someoneconfirm 80 mm.

Thanks

Noah

Hey Guys - Just picked up my new Beaver w/ floats. Just curious on thoughts about an engine. My plan was to use a G26. Will that be enough power on land and on the floats? I see one of you is planning a ZDZ 40. Just curious. Thanks. Ham870

Hello,

I did go with the ZDZ 40, and it's way more power than this plane requires. I will say, however, that I have not yet flown it off water. So I don;'t yet know if I'll really need all that power. I also should tell you that I have not even weighed the finished plane. Sometimes it best not to know!

My hope is to fly it soon with the floats. I didn't get the plane finished before our annual float fly, and it's more complicated to fly from water in my area, as the only reasonable body of water is within a state park (must get clearance with Rangers well in advance).

But in general, the plane flys beautifully and it's very easy to manage. Slows well for landing, especially with the flaps... they are VERY effective. Be ready on the rudder if there's even a hint of cross-wind. Likes to weathervane.

Good luck.

Noah

What Morromaxx mentioned are most of the modes you'll need... One mod a fellow I know did was to shorten the float stuts to more of a scale length... What he did was take a 3-view (Beaver on floats) and just scaled up the measurments to get a better looking scale float strut and spredder dimensions... Here's a pic of his..

Looks great guys! Here are a few of mine. I've made similar mods as well. Incidence was WAY off. Also going to use a Ernst rudder. Saito 1.7 radial w/ glow charger. Flew fine of the wheels and with flaps was easily 'greased' in. More to follow.

The G-26 is more than enough to fly this plane. Mine is a heavy pig at 23# but still flys good on the G26. As others said the step and incidence is WAY off if built from the instructions. As far as the float spread, 18" is scale. I pulled measurements from 2 different full scale Beavers on everything before I started mine as far as spread, and mount locations. Then 25% rule is for sport, not scale.

http://media.putfile.com/KMP-Beaver-v2006

Finally flew from the water yesterday!

Plane was fantastic. Only a few clicks of down and it was flying true. In my nervousness and excitement, I started my first turn after climb-out without rudder and it was very ugly, so for those that have not yet flown with all the added drag and weight of the floats, be sure to steer the plane with rudder! Same really applies to to wheeled flight as well.

Take off "roll" was straight as an arrow and the plane tracked through the water perfectly. I have also re-set the wing (relative to top of float) incidence at +2.5 degrees. To do this I had to cut and drill new struts. Pretty easy to do. I also added steps up to each door, which also helps make the rigging a little more rigid. Used a single Ernst water rudder with (what I believe to be) more scale pull-pull rigging. It may not be visible in the photos, but I used a tiller on the tail wheel, Spyder wire (kevlar), and Proctor pulleys. Pulleys have to go as they don't roll worth a darn. Trying to locate some (small) ball bearing pulleys, so that the action is smoother (water rudder won't easily return to neutral with air rudder is neutralized). Needs more work.

I have the float step located 1.5 inches behind the CG (80mm). Seemed perfect, too. I have no ventral fin, and likely will not add one. Plane was very stable. Was pretty windy and the plane's size and weight handled it beautifully. Finished weight with floats still unknown (guessing about 17 lbs).

Love the plane!

Hope the photos attach.

Noah

Well, I spent way too much time on the internet today looking for suitable replacemement pulleys. In another thread, Akflyer, or maybe it was PaulGC, was also looking into getting some smooth-functioning pulleys for their scale water rudder rigging... if either of you two see this message, let me know if you were you able to locate some.

Ideally the pulleys should be no more than 1/4 inch outside diameter. Proctors are perfect in their size, but the brass wheel just will not roll very well when tension is applied. Maybe I just need to ease off the tension.

Anybody have any suggestions?

Thanks

Well my assumption that there was too much resistance in the pulleys themselves proved incorrect. I finally got another set of hands to help me directly test this last night, and even with a great deal of tension on the lines, the pulleys rolled smoothly. It turns out that the Ernst rudder itself is sticky.

I tried to lubricate the nylon-nylon contacts with Tri-Flow, but no luck. I think that I'll have to now modify the water rudder or make my own. I have no doubt that the Ernst rudder would function just fine if connected to a nyrod or the like, but in the stock configuration, and using pull-pull with kevlar lines, the movement isn't free enough.

I searched to see if others were struggling with a similar problem, but I found nothing. Anyway, I just thought I'd throw this out there to see if anyone had similar issues or whether someone has any recommendations for improving the movement of the Ernst rudder.

Help,
I also building the Kmp Beaver. I'm attempting to mount a 180 Saito in her. Looking for advice or pictures of examples if any one might have attemped this before me.

I am planning to buy this 95" ws KMP Kit and I shall have someone (my model-maker) put it together for me. I have several questions regarding this Kit.

(a) Do the main wings come apart for transportation purposes?
(b) What size (oz/in) servos are required and how many?
(c) What are size of the wheels and are they rubber or foam?
(d) What is the largest size engine (cu. inches) the cowl can take? Would a G38 fit in completely?
(e) Chief Aircraft is seeling this Beaver for $530.00 inclusing shipping. Is this the going price or is it cheaper at some specific website?

Can someone respond back with accurate answers?

(A) Yes, the wing is a 2-piece set up. Each panel slides onto a wing tube.
(B) Each control surface is pretty large, and it of course would depend on how fast you fly it around, but I would say that 70-75 oz/in at a minimum on the elevator and rudder.
(C) Wheels are foam, 4 inches in diameter.
(D) I don't have any experience with the G38, but I would guess that you'll have to cut the cowl to accommodate the muffler and/or carb. I'm using a ZDZ 40 with a rear mounted carb and a pitts-style muffler. I had to open the left side of the cowl to make room for the muffler. (see photo below)
(E) Considering that I paid $630 from my local hobby shop, I'd say that $530 is a good price, especially if floats are included.

Thanks for your early response. The answers seem to be in sync with what I was expecting. The model looks superb in the photo. I will order my model in the next couple of weeks without the floats.

Hello Sbrabiero, Just finished my KMP Beaver and am having a BIG problem maintaining runway heading. I seem to get it trcking straight and them it breaks 45 deg to the runway? I have not installed the horiz fins - should I?? Do you use flaps for T.O.? Need help!Barking (Larry)

What servos did everyone go with? I was thinking the HS-645MG all around. I'm using a gas engine so I want to stay away from karbonite gears.

Good info here. I just ordered a Z....G26 for my KMP Beaver and want to put a Bisson muffler on it. Is there enough room for a wraparound pitts style with the flat firewall or will I need the inline straight down style muffler?

Steve

Steve,

I don't own any Zenoahs, so I'm not sure what you'll be faced with when you go to install that muffler.

I can provide you with measurements from my plane/installation (firewall to cowl opening, depth of cowl, etc...). That way you might be able to pre-determine whether your wrap-around configuration will work, and whether you'll need stand-offs of a specific length. I will say that the cowl is not very deep, though.

Let me know if you want me to take those measurements.

Noah

Thanks Noah. I have the plane so I don't need the measurements. I guess I'll need to wait until the engine comes in. I'm already pretty sure there will not be enough depth for the inverted wraparound type muffler. I was wondering if anyone had confirmed that with this particular engine.

Steve

Barking, what you describe is what happens if you did'nt correct the wing/float incidence from the way the kit is designed. You can check other threads on the KMP Beaver on how to remedy this but the bottom line is that you have to get the floats adjusted so they are 2-3 degrees negative to the mean chord line of the wing.
If the plane sits quite tail down in the water you have an incidence problem. Proper set up is essential on the Beaver and it appears KMP didn't do their homework on this one.
Peter

Regarding the incidence, here are some measurements that I took from my plane. I think that if you follow these guidelines, you end up with the correct incidence on your own plane.