PKZ P-51: 7channel fun

[19000rpm]

I've been without a P-51 since I crashed on takeoff (Had the rudder channel reversed ) in Sept.

I decided to do up a new one with all the goodies: Power 10 motor, eflite 10-15 retracts, flaps, rudder, steerable tail wheel and machine guns. Yes, machine guns. Well, not real machine guns, LED's that light up like machine guns.

I'll post some pics soon.

[akent]

Sounds incredible!
I can't wait to see this one.

What retracts are you using?

I assume it really will still be the PKZ P-51?

[19000rpm]

Yep, it's the PKZ "Gunfighter".

Because of the wing thickness I'm going with the Eflite 10-15 retracts. These barely fit, but they don't require a servo so overall they are a very compact unit. They also have a very strong landing gear and the locking mechanism, up and down, is very robust.

Here's what I did: 1) After taking all measurements to ensure the gears would work in the wing configuration, The depth of the gear body and wing thickness were the critical ones,

2) I laid out everything in pen on the surface.

3)The next step was to cut the outline with a fresh hobby knife. I put a piece of tape on the side of the knife, as a guide, to keep the cut deep enough for the gear and wheels, but not so deep as to penetrate the top surface of the wing. It's multi depth cut with the mounting plate just slightly under the surface.

4) I routed out the foam with the Dremel cutting tool.

5) I cut some thin ply for the gear body mounting surfaces and CA'd those in. I'll go back and epoxy those areas.

6) I installed the gears and tested to see that everything worked smoothly. A few adjustments were neccessary in the foam.

7) I cut a plastic disk out for the bottom of each wheel well so it will look more finished.

Here are some pics.

[r/c basher]

Cant wait to see it when its done. Sounds like an awesome build.

[akent]

Wow 19k!!!!
That looks better than any factory installation I've seen!

I can't believe how good the wheel wells look!
Awesome!

Mine will have to get modded like that!!
I love it!
Kent

[19000rpm]

Thanks, Kent. I think these mods are going to be worth your effort. You should end up with a very scale looking bird both in appearance and, in particular, scale type landings and takeoffs, while having a very fast sport plane to boot.

I'm lucky to still have a steady hand for the cutting and routing. Even at that, I ended up getting a little too close to the top of the wing when I was cutting and routing for the gear body. There's less than 1/16" of foam left to the wings top surface when the gear body cut out is completed. I made a couple of plastic panels for the top of the wing to reinforce the areas where it's very thin. When the panels are painted they'll hardly be noticeable.

There's plenty of foam where the wheel retracts. You still need to be careful, but it's not as critical a depth as the gear body area.

Now that the retracts are done I'll cut the flaps and the servo pockets for the flaps. This will be a piece of cake after doing the retracts.

The flaps will require some mixing with the elevator to keep the nose level when the flaps are deployed. That will take some experimentation on my part. ;D

[19000rpm]

I finished cutting the flaps and dry fit the servos.


I'm guessing on the full flap position. Once I have it all together this may require additional adjustment.


I widened the wire channel in the wing. I need a wire extension for the retracts and a Y harness with a servo reverser for the flaps as well.

I'll primer and paint the wing next and then install all the servos and the retracts.

[fireguzzi]

Looking like its going to be a cool plane.

[19000rpm]

Thanks fire.

I think I'll keep the Gunfighter markings with a few subtle mods until the paint needs re-doing...Hopefully it'll last that long. Landings on a narrow ice road with icey banks on both sides can get somewhat treacherous.

[19000rpm]

I've completed the wing except for the taping of the wire channels servos and retract areas that are black with a silver color. The plastic is kind of shaped like the gun access but in reverse.


I added some plastic over the area where the body of the servo was getting close to the surface. They are barely visible when painted.


The lack of depth of the wing will probably eliminate my plan to add faux gear doors. The doors wouldn't be flush with the wing.


I'll be adding some wheels that look more realistic. I was planning on the Dubro Super lite 2" wheels but the hub is so small the gear/axle joint almost covers up the entire wheel hub.

[Gabe]

Wow - she looks real clean. Flaps and gears are the stuff dreams are made of. Nice work!

[19000rpm]

Thanks, Gabe.

One more thing I'm going to add to the wing is an additional spar. It may or may not be needed, but I'm going to do it.

[19000rpm]

OK, here it is: a 3mm tube spar running out to the aileron servo pockets between the wire channel and the fiberglass spar. I think I'm ready for some high speed maneuvers now...When I can find a piece of surface clear of snow to operate from. That may be awhile.

[Gabe]

Looks good to go! I can't wait for the flight report. I'm so envious.

[19000rpm]

I'm hoping to find a parking lot that is plowed well enough to do a test soon.