New P-38 profile scratch build log

I remember when you made those gaskets roddie, a lot of them as I recall.  

Seeds, yes, I know them well as I flew over grass a lot when I was starting.  

I was close.  It's Brodak fuel and SIG castor.  I don't know if 5% is enough to tickle these engines into life.  I will start with my less cloudy Cox fuel and go down from there.  Traxxis is 10%.  

Battery is dead, dead, dead.  I'm afraid to hitch the big charger up to this little battery so it's the trickle for now, a hour or two I would think.  Might be tomorrow before I try them.  Clamped 2X4 should hold harmonic vibrations down.  




Big Brother Cox under construction

The 5% fuel was designed for the those that insist on running 29% oil in their Fox .35's. A 1/2A requires heat and your offering it the complete opposite . While it might run, it makes starting more difficult and  needling extremely problematic . When the oil content is too high as is 29%, it makes the engine just shut off abruptly due to the plug cooling off. I'm certain as long as your Cox fuel has been tightly sealed, it's just fine.

Ken Cook wrote:The 5% fuel was designed for the those that insist on running 29% oil in their Fox .35's. A 1/2A requires heat and your offering it the complete opposite . While it might run, it makes starting more difficult and  needling extremely problematic . When the oil content is too high as is 29%, it makes the engine just shut off abruptly due to the plug cooling off. I'm certain as long as your Cox fuel has been tightly sealed, it's just fine.

You're right Ken, the 35% worked just fine, and it was easy.

I filled both tanks with it and opened the needles about 3 ½ turns.  Primed the engine on the right and flipped it a couple of times and it took off running great with little needle adjustment.  Then I thought, I don't have my camera..........nobody's going to believe me.

Turned the needle in to shut it down.....I don't like the "cloth stopping method".  Got the camera.

It would not start again.  Got out the electric starter....I don't like to use them but hit it.  Took off again running great and I it let it run the tank out to the bottom of the pick-up.  (No centrifugal force to empty it completely.)

Same thing for the second engine.  I knew these would be great runners, compression was right and new glow plugs.  After 75 years of fooling around with them, you just get a feel.






No way I'm mounting those nasty engines on my nice clean airplane, got to be wiped down first.  I should give them an alcohol bath but I don't want to mess with success.  

I was surprised to see the battery charger reading steady green, fully charged.  I was intending to remove some vines killing one of my trees not dealing with model airplane engines.  Did both.

As I had the camera............

Cleaned up those engines, painted the tips of the P-38's fins, and rigged some lines.  Cases loosened and drained, backplates stay on.  Lot's of CW/CCW rotation while immersed, compressed air blowout.  MMO protected.  







Just the natural fall of the lines, follows the taper of the wing.





Not glued in, got to form the ends and secure.  Swivels will go on the handle not the airplane.  I have the more appropriate safer double lock keepers but I like these.  I have used them on larger airplanes without a problem.

One way or the other, there will be Dacron. My shortest twisted steel lines are 52' which will drag this plane down. I'm thinking 30' - 35' Dacron.

The P-38 is coming along great! With a colour-coordinated control handle too

I was going through my ”archives” the other day, and found a magazine cover I thought you might like. The Aviation Museum in Helsinki was giving away old magazines a few years ago, and I grabbed a few.



There was a short article too::



In another magazine (not from the museum, this one I received as a subscriber) was a plan of a P-38 chuck glider. Curiously it’s a low-wing design, but it would be easy to change that. I built the other, more conventional design of the PIK-15 ”Hinu” back then.

Can't fly a plane without a matching handle Kari.........



Levent did a real good job on the illustrations color matching the background and leaving me trim area.  I printed out test samples on computer paper and real ones on white backed water-slide.  Still some trimming to do. Clear water-slide doesn't do as the illustrations fade.  





I found some proper 3' length music wire for the lead-outs up in the loft and used that.  Didn't have to splice.  



I showed it to my son today........he says he gets first dibs...........

Finished although I may let it sit for a few days then give it an overall coat of gloss clear blending everything in and double protecting the decals.  




I was wondering how much weight three coats of sanding sealer and two coats of paint plus other stuff I hung on it would add.  

1107/1227 oz.





I really like that matched pair of early Babe Bees.  Different appearing from normal and great runners.  

Perfect work Bob, as always

My favorite models in your fleet are La Viuda Negra, Airtruk and this one.

Thanks, They all have a little touch of Levent and Robert in them...........

Thanks Joe and Robert......

I'm already thinking about another one.  I really like roddie's five piece flat wing on his P-38.  I have balsa and engines to spare and imitation is the sincerest form....

Layed out the control line.  Good old used and proven vintage Dacron that came with something or other.  Even the line is olive drab, or is that castor/fuel staining.  Might be ten years old or fifty.  Measures 25' 6", pretty close to my 34' target.  Pull test occurs when it just gets airborne.  

Triplet twins.





Someone misjudged the wing to tail moment. It might have been me.

If you pick it up where your first lead out is exiting on both wingtips, I would hope it noses down otherwise your probably real tail heavy. I also feel if your going to fly this, you might want longer lines seeing you had dizzy spells last time. Two engines regardless that they're Bees are going to be quite fast.

Ken Cook wrote:If you pick it up where your first lead out is exiting on both wingtips, I would hope it noses down otherwise your probably real tail heavy. I also feel if your going to fly this, you might want longer lines seeing you had dizzy spells last time. Two engines regardless that they're Bees are going to be quite fast.

It looks to me like it's going to balance.. but if it doesn't.. you can add functional nose-weight by using a heavier wheel on the nose-gear. You could B & S (bush and sandwich) a 1" fender-washer patty, between a pair of 1/16" balsa-buns) in an extreme case..

I agree with Ken on the lines.. not only for his reasoning.. but also for an upgrade in the integrity of the lines. At least consider Dacron from known-unused spools. Here's a scenario...... It's "Maiden Day" for your P-38 and you're using those dirty, old, used, suspect, no documented-history) Dacron lines.. your pitman/mechanic (Son Mark) gets your thumbs-up/motion to launch.. Bee's singing happily.. you give the signal and the model taxi's out........ now it's AIRBORNE.... and reacting predictably to you handle-inputs! It's really feeling good after 5-6 laps.. but without any warning.. your P-38's lines succumb to ADLF (Aged Dacron Line Fatigue) and the model goes on an uncontrollable rampage of terror.. what do you do? Do you hang on? Do you let go......

Thanks Ken and roddie.

My above - "layed out the control line" was written somewhat tongue in cheek. While I'm sure that it would hold, my intent is to use new Dacron closer to my 30'/34' intended length. The problem is - finding a place to fly it from or more accurately to take it off. I could have Mark toss it, but that's a sure diaster. On a new plane I have to see what it's initial tendencies are. A circle or an upside down U.

Picking it up as Ken described it has perfect balance, neither nose down or up. Somewhat different from when I used the balance pegs under the wing. For fun I looked at Cox tri blades. If it survives perhaps for display. I will probably paint the spinners the same olive color but either yellow or red looks good. Keeping the Windsors for flying as on the test stand they were pushing air pretty good.



I'm disappointed in the latest white backed water-slide paper from Koala. It's not as thin as in the past and leaves a halo. I will probably give it a coat of clear.

looks great Bob Im greatly looking foward to the flight report. The twin engines adds extra spice.

Darn your done already ! Cool looking plane you have done it rightest . Good it balanced out for you in the end and the paint and decals bring the shine out . If it were me i would stay close to the 40' mark for the lines Hope the median goes good for you ..

getback wrote:Darn your done already ! Cool looking plane you have done it rightest . Good it balanced out for you in the end and the paint and decals bring the shine out . If it were me i would stay close to the 40' mark for the lines  Hope the median goes good for you ..  

Well I thought I was done but debated whether or not I should clear coat it, my son thought I should so I did.  Not sure I like it, no longer satin but a shiney plastic airplane look.  I'll let it cool off for a couple of weeks then put the engines back on.  



I have taken 1/2A airplanes off the driveway before, but it's a tight circle.  Picked one out of a tree.  But the electric Cox Bearcat did well there.




While waiting for the plane to dry I removed the head on the Cox/Rhino/etc engine and thought - Ain't that something, my fathers favorite expression although he used better English.  No combustion.  I don't think that it was ever ran.  





The other engines were not quite so pretty:

So, "just for the fun of it" I drove a stake in the ground to secure the control handle and using my previously mentioned olive drab Dacron 26'.5 line checked distances to potential obstacles.  





Ok, it's to close to the garage so I moved the stake over and down about four feet and checked again.  







I think I could do it.  Starting at the extreme edge of the driveway I think it would get airborne before I hit the grass, if not the worst thing that could happen is a tumble landing upside down.  Airborne?  The worst thing would be a stall over the asphalt.  Splinters..........

Fuel it up, let the engines run a minute or so with a final squirt in the inside engine and let it go.  Not to worry about that Dacron, it's in great shape and would hold, if I thought differently I would change it.  

Hi rsv1cox,
Beautiful P-38 ! Cox powered at it's best !
I used those rolls of dacron for decades. (max 33ft handle/plane)
Then I tried new 'fishing line' methods.
Same plane, at 42ft radius...Wow what a difference ! Slower laps and way more 'room' to manouver.
(BW.049, my version of a Flightstreak, I have never flown a twin)
Good luck on the test flights.
I have also taken off standing at centre field, and hit football field goalposts, levelling off for landings...
Your results will vary...
Take care,
Have fun,
Dave

Thanks Robert and Dave........

Wishing you luck, I know you want to fly it

 I really do.  I get that "just do it" urge, hits me spontaneously but I need to know the parameters first, I don't want to wrap it around a tree before I get a lap or two in.  

The problem is I have to fly it in a restricted space, there is just no place around to fly C/L.  I might be able to go out to 30', we will see.  I have to take it off a flat smooth surface.

I might get out the stooge one day and "just do it."