New P-38 profile scratch build log

BOB how about that field you wee cleaning ?? Alot more room there and go to 42' Like Ken said some tip weight for line tension / card board take off land in the grass . I would bee scared at what your showing / with very little line time in too

Maybe some left-handed (clockwise turning) props might add a bit of line tension. I think the lines should be at least 35'to 42'  foot long and use some of that nice fishing line that is stronger and thinner than the old dacron stuff. F.  ind someplace where you have some room to fly that beautiful bird . Good luck with the maiden flight Bob.

                                                                        Mike1484

Thanks Eric and Mike. The field is my best option but I would have to lay a lot of cardboard for a proper take-off run. I have saved some up but I don't think it's nearly enough. I have flown a Cox PT-19 there, but I think Mark tossed it. Still, after a few laps I was so dizzy I had to dump it.

I could warmup with my flaps plane and longer lines. Mark flew it in the field a couple of years ago and did not like it, but no crash. But I would really like to see my escapement converted to C/L plane fly but not by me. Big wheels might enable it to be taken-off from grass. I like that one.




I do have some "spider-wire", hadn't thought of it in awhile. Will look into it and re-measure.

Bob, I have seen rolls of thin but strong cardboard on construction sites to protect flooring… I think you can get it a larger home stores…. Just don’t know how much is in a roll…. Would be nice to have a long runway with no seams

Hi Robert! That model really pops.. sitting there outdoors in the natural light of day.



Really nice job Robert! I learned to fly on sub 30 foot Dacron.. for pretty much the same reason as you. My safe-circle permitted 26 foot lines.. which gave me less than 3 feet clearance between two opposing stone walls, a high tree branch hazard and the shrubs along the side-foundation of the house. There was a break in the shrubs for access to a water spigot and an elec. outlet. This was my pit-area. My launching-stooge was less than 8 feet from the house. 26 feet straight-out from the stooge was center-circle which was marked using the lid from a 5 gal. plastic bucket, pinned into the sod with a single 7" aluminum gutter-nail. I could feel the lid underfoot.. and never needed to look at it for a point of reference.

How much distance (inches) between the prop-arcs and the ground? If less than one inch.. you might want to try increasing the wheel diameter to achieve at least that distance.. if there's a chance of taxiing over grass.

Let's consider that you decide to fly the circuit off your asphalt driveway. Ken Cook mentioned weighting the outboard wingtip with some clay for the initial "roll-out" to help with line tension. That sounds like good advice to me. Where the asphalt transitions to lawn.. you could try laying a piece of "tar-paper" (or similar thin but heavy sheet-material..) for the purpose of providing a smoother transition into the grass. Truthfully........... I wouldn't be surprised if this model was capable of ROG directly from the grass. If you're skeptical.. run both mounted-engines up to speed while holding the model in your hand(s).. You're gonna feel some pulling-power, believe me.

On another note.. I was thinking about something that I wanted share with you regarding a static display for this model. Something to add some realism.. at the field.. or as a prop in a diorama while hangared.



or...



Imagine... a 1:18 (?) scale tanker-truck that was actually "functional"...... with a 1/2 pint(?) glow-fuel tank retrofitted.. and an electric fuel-pump. Why not build a power-panel disguised as an AVGAS fuel-tanker? The possibilities are endless.

Timely roddie, I took a few minutes this afternoon to re-rail my de-railed Cox Army trains.




 Love that 1/18th Studebaker truck, now you have me hunting for one.  My rusty but trusty 1951 $250.00 Studebaker Commander (powered by Studebakers first V- bought on boot camp leave successfully transported me and my wife 1500 miles down to Pensacola from our home town in New Hampshire back in 1956.


But, thanks to you and Ken for reminding me.  I never added any tip weight to the P-38.  Forgot about it.  No washer/quarter glued to the wingtip.  A chunk of clay will work nicely.

I left that peg in the lawn, a good circle point base.  I just know that sometime I'm going to get the urge and spin those engines over and try it as is...............

Yes, I want to build another using your 5 point balsa wing inserts.

Edit add:

I found that truck roddie. China. It's 1/43 scale. Pricey @ $108.00 but shipping from China only $6.00

Yes, I want to build another using your 5 point balsa wing inserts.

Here's my design/drawing.. a 26" span/slab-wing profile.. Pretty much the same size as the one that you just finished.



The graph-paper shown is ruled in .25 inch squares.. so you could use this photo to scale to your liking. I'm slacking.. there's usually more construction notes on my drawings.

It's important to note that my slab-wing's main component is not balsawood.

The main/central component is a "slat" from a Venician window-blind. I'd found the wood in a garage that was being cleaned-out. Someone had stripped a blind down for its' slats at some point. I picked up one of the slats and thought; this is definitely wood.. but not as lightweight as balsa. I believe it's basswood.. but that's just a guess.





So... my wing-design has a hybrid bass/balsawood construction which lends strength to the overall design; especially at the intersections of the twin-booms.. and also providing rigid bracing for the gear-blocks. You shouldn't have issues sourcing basswood.. but I'd be glad to mail an original piece to you.. if you want to follow my wing-plan. There's X8 slats remaining....   and they're all dead-straight.



You may remember my "Flying Blind" design.. that was built almost entirely from "one slat" of that wood.





The only balsa components in that airplane are in the elevator.. to facilitate hinging.

Thanks roddie, I grabbed it. Will print it out in four sections and tape it together.

Bob

I have been thinking about this:



A 10" X 8' board, a couple of carriage bolts, two rubber bands from a Gillows kit, track guide for the front wheel, and a release mechanism.  I have all that stuff.  Get's me out in the field where I have plenty of room.  Engines fully leaned out...........Might have a chance if the props don't pick up the rubber bands. The rubber bands should be placed inside the outer wheels.

rsv1cox wrote:I have been thinking about this:



A 10" X 8' board, a couple of carriage bolts, two rubber bands from a Gillows kit, track guide for the front wheel, and a release mechanism.  I have all that stuff.  Get's me out in the field where I have plenty of room.  Engines fully leaned out...........Might have a chance if the props don't pick up the rubber bands.  The rubber bands should be placed inside the outer wheels.  

A catapult-stooge!! I like the incline. Do you have an alternate heavy nose-wheel that you can use for the maiden.. just to play it safe?

I don't know roddie, I'm just thinking out loud hoping that some one will tell me "It ain't gonna work!"



The bands have to be kept down low.  I'll make a 3D model someday.  Seems I developed a new kit.  Competition for Guillows.  

I have been meaning to ask.  Why the two right angle I holes in your wing?

i wont do it, cause I am cheeep

but there is a sterling kit for sale now
https://www.rcgroups.com/forums/showthread.php?4459711-Sterling-P-38-CL-Kit

way too rich for me, but still....

cstatman wrote:i wont do it,  cause I am cheeep

but there is a sterling kit for sale now
https://www.rcgroups.com/forums/showthread.php?4459711-Sterling-P-38-CL-Kit

way too rich for me,   but still....

You reached back aways for this one Charles.  There are two, one at $75 the other at $80.  But I too will have to pass, sacrilege for me giving up on a P-38.  But I have been way too good to me lately in the hobby dept.  

My P-38 cost me nothing.  I had everything on hand. But, were I to add everything up - wheels from Bernie, airfoil wings from SIG, goo smacked engines from ebay, paint, epoxy and CA I might have $35/$40 in it.

Actually the cost of $75 US is not a bad cost for the larger 36-in. .09-.15 powered one, especially when one is pricing a new kit made by laser cutting, which may also lack some of the hardware like landing gears.

I already have that kit but not yet built. Outerzone has the Sterling half-A plan, so one can recreate it from scratch.

The twin tailed devil has always been a classic favorite. Another that would make a good one is the Focke-Wulfe TA-154 Moskito. Here is a control line plan for a 38 inch wingspan version for two .09's - .15's. One could easily make it a profile, downsize to half-A for something different.

https://outerzone.co.uk/plan_details.asp?ID=912 Plan #912 - Focke-Wulf Ta 154 Moskito by Peter Wheldon from Model Aircraft December 1959


Outerzone photo.

rsv1cox wrote:I don't know roddie, I'm just thinking out loud hoping that some one will tell me "It ain't gonna work!"



The bands have to be kept down low.  I'll make a 3D model someday.  Seems I developed a new kit.  Competition for Guillows.  

I have been meaning to ask.  Why the two right angle I holes in your wing?

I honestly like the catapult concept Robert. I don't think that you'd need it for this model though. I mentioned maybe fitting a heavier nose-wheel for the maiden.. just in case you've got a tail-heavy airplane. If not; no harm.. no foul.

You could possibly maiden (R.O.G. launch) from a short-cropped grass field by using wider-tracking tires. Make them yourself, by cutting strips of thin plastic.. approx. 1/2" to 3/4" wide.. long enough to wrap-around the circumference of the wheels you're using.. and secure the strips with a piece of tape. They only have to stay-on until the model lifts-off. There's less chance of the struts "snagging" in the grass.. and a better chance of the wheels "rolling-over" the grass.. rather than having to plow through it. How short will your J-Deere zero-turn mower cut? Imagine how much fun it would be.. to cut a 100 foot diameter circle.. expressly for your model aerodrome!

Your inclined catapult stooge concept (ICS) seems like a real attractive option for anyone wishing to launch their small C/L airplane with small wheels... (most Cox RTF models) from a grass field; where most pilots would prefer to fly over.. rather than hard-pack/pavement. I'll think about the catapult mechanism.. and how it might be applied to most models via their gear-struts. I have a "take-off dolly" design that uses two strips that lay-over the stab. to prevent the tail from "popping-up".. until the model moves forward several inches. Some sm. size shock-cord might work.. and would not foul the propeller when recoiling.

oh.... yes.. regarding the two right-angle I holes in my P38's wing.. The main-central panel is actually a venetian-blind slat made of basswood.. I think.



The panels' .135" thickness.. 2.375" width and 24.0" length made a nice foundation for adding .125" (1/8") balsa-wood tapering leading and trailing edges.. of which I used 2" width strips that I had on-hand.. and also for the wing-tip stock.. which made-up the 26" span that I wanted.



The "I-holes" are where the stringers (?) went through the slats for the venetian-blinds. I plugged them when adding the balsa contours to the wing.

Thanks roddie for jogging my memory. Now I remember that you mentioned part of the wing was made up from a venetian blind. Pretty clever repurposing. Now I have to find an old wooden blind.

rsv1cox wrote:Thanks roddie for jogging my memory.  Now I remember that you mentioned part of the wing was made up from a venetian blind.  Pretty clever repurposing.  Now I have to find an old wooden blind.    

I'm putting together a muffler-kit for you to try... and I have eight of those basswood blind-slats. You'll save some of your 1/8" balsa reserves if I send you one. I'll send you one because that's what the plan I sent you calls for. It serves as a "wing-spar".. but also provides for a more rigid mounting for the booms. It's actually a very centralized high-strength component.. having a minimal weight penalty.

My designs' TE and LE stock was from 1/8" balsa.. 2" wide. Two 12" lengths cut diagonally makes them. You can also butt-joint 1" wide strips together lengthwise to make the 2" width panel-stock. I really love this part of it.. (as if you can't tell..)

Tail-feathers are all from 1/8" balsa sheet. Booms are 1/4" balsa sheet. Minimal stock for a twin really.. but that's what we all love about Lockheed's designs.