My P-38 for 2015, my "Wicked Woman"

[Brenda]

As I was working along I thought "Ummm prop?" seems I didn't have correct size prop laying about soooooo....

[John G Jedinak]

Extremely IMPRESSIVE!!!!!

[Brenda]

Extremely IMPRESSIVE!!!!!

Not really. Either I am to cheap to buy 5in props from Guillows or trying to keep plastic out of my build...or a little of both.... honestly tho Comet has directions on how to build 3 blade props. If you follow them to the letter you will get nice props. If you look you can see white paper where blades come in, each prop has a V on the bottom, when jammed into paper the V's will only fit one way thus straight and true prop. Methinks Goldberg came up with this as the man was pure genius

[John G Jedinak]

Well, if not impressive...how about...SLICK!!!!

[Wildpig]

Well, I'm impressed. Making that perfect hexagonal prop hub and paper template required some talent. I don't suppose you could post or tell me (us) what those instructions are for making 3 blade props? I would like to try that on my P-38.

P.S. I think you are right about Goldberg.

[Brenda]

Sure. Have to wait on the sun as I work outside. I'll take photos and build a few more. Only takes a few moments to make them. Comet had instructions for 2, 3, 4 and 6 blade props. Even counter rotate on same shaft.

[H65 Driver]

Were those hex block hubs laser cut like the props or did you have to carve them yourself? Is that a "Sam's Models" kit and if so, do they ship from the UK to the US?

[Mitch]

Okay Guys and Gals... I'm home now... I plan to use kit props for now in my P-38.

Here is the progress so far:

Cutting holes was easy with these neat little hole saws and sanding discs with my dremel tools.


Wing construction with magnets.


The mock-up.


Close up of wing and fuselage.

The fuselage was easy to bore out. I only did one as I want to compare the weight differences.

More pictures coming, and I have to order some more silver paper.

Mitch

PS: This has been ALL kit parts and wood so far. The only alteration I made so far is to add a second rear peg position 2 bays forward. I plan to use the Guillow location for Guillow rubber. Then when I switch to tan rubber I will be adding more strands and the fuselage is not wide enough that far back. I will keep that rubber 'center of mass' over the cg of the plane. The second rear peg position is forward of the air coolers.

Secondly. Now that I am home I will start construction on the nose blocks. They will be of scrap balsa and plywood and a few small wood screws.

Thirdly. I plan to cover the model with lightweight silver paper and use copies of the decals provided with a supplement of copies of markings from my reference book on the "Wicked Woman"!

This model is being built for the 2015 Guillow challenge, but if it flies well I will submit this model in the Jumbo scale (over 36" ws) in WESTFAC V. It NEEDS to fly for at least 20 seconds. I still will finish my Me109Z and enter that in 'Double Trouble mass launch'.

[davidchoate]

Cheapness is the Mother of invention. Or at least improvisation. Super nice work. I was wondering how you were going to deal with all that weight. I have only seen the P-38 frame in the catalog, and it looks laiden down in plastic. You think She will Fly well ?

[Mitch]

I think the biggest problem of plastic weight is the air coolers. Although I have trimmed them down as per 'Rubber Flying model' They are still heavy.

The air coolers with skin siding weigh 18 grams. Without weigh 10 grams. That's just one set. That means 20 grams, plus at least 20 grams of ballast. That is a 40 gram penalty. I think that is too much. I may have those for photo shoot only and fly model w/o air coolers.

There are still 2 more sheets of plastic I have not even cut into. They will not be used at all.

So the only plastic I will have on the flying model are the wing cowling/superchargers, front cowlings, some small louvers, and canopy.

I am pleased with my 'lightening' of the fuselage. I saved 5 grams, plus enlarged the openings for more rubber.

Fuselage on left is 'lightened'. Fuselage on right is as per plans. They weigh 18 grams and 23 grams. I still will lighten the tail a bit more and remove some of the TE from the wing. I will then weigh all the component parts.

I could have placed the rear peg at the location of the air coolers, but will proceed with my plan. I will hopefully fly this model in about 2 weeks and have my recommendations for a rubber power P-38.

Mitch

PS: I do not expect this plane to fly well, but hope to get a picture of her in the air. I am hoping for a 10 second flight... we will see.
When Guillow makes this kit available in laser cut, I plan to look at the spare parts and buy a 'short kit' as there is a lot in this kit I did not use.

A Question to all of you: I calculate my wing area to be 185 square inches. I have been told that I should not subtract the area that is covered by the fuselage. This plane has 2 fuselages and the cockpit nacelle. All of these block a lot of the lifting surface. Is it still correct to not deduct any 'wing area' for these parts?

[Wildpig]

A Question to all of you: I calculate my wing area to be 185 square inches. I have been told that I should not subtract the area that is covered by the fuselage. This plane has 2 fuselages and the cockpit nacelle. All of these block a lot of the lifting surface. Is it still correct to not deduct any 'wing area' for these parts?

Standard practice for calculating wing area for models and full size airplanes is to include the nacelle and/or fuselage area. Lift continues over these parts, it's doesn't end and begin at a fuselage or such. Fuselages and such do modify the lift distribution across the total wingspan. But, to keep things standardized, just use the wing area across the nacelles/fuselage as if they are not there.

[Brenda]

Getting a few more bits put on and glued down.

[Mitch]

Thanks to Widpig for a very nice and complete answer.

Brenda, are you going to leave those wheels on? My P-38 will be gear up. I will get back to it soon. I think the wood work on the FW190 is finished. So I will make space for the P-38 now.

I hope to get back to work on the P-38 but I am working another job and dance classes take up the evenings. Also working on plastic models and coordinating the next model train show... I need to retire soon!

Mitch

PS: Here are some models I brought to a recently model show:

These are Plastic 1/48 scale Eduards kits. I just fixed the broken landing gear on the SE5a and need to re do some of the rigging, and then broke the Pfalz getting them home. The SPAD has no rigging yet, but will get that soon, and I just opened up a box with a Nieuport 17.

One guy was showing these little metal models he likes, I thought this was a plastic club? At the swap meet table there was an old Guillow model, that gave me an idea, there were a few youngsters there also. I think next month I will bring in a Guillow model and show them how its done! They all know of Skyway Model Shop and that is where my Messerschmidt 109 is hanging. I think I will show them a few more!

Mitch...spreading the fun of flying models, one day at a time!

[Brenda]

Howdy Mitch,

Due to the fact I can't be coordinated enough to do a twin hand launch I'm going for ROG. I have 3 sets of props to use. Guillows 5in red, Comet hand made 3 blade and wooden 3 blade counter rotating from Shortys Basement. I also had to buy some F.A.I. tan 1/4in from Shorty to try along with round tan and Comet grey. The grey from the 1960's still works but I'm afraid it will twist the props right off.

[Mitch]

Okay, If you are going ROG, I think the tide swept back into my favor. I am planning hand launch.

Here is the trick to get the props ready in position. The P-38 is perfect as there are 2 small air intakes on the engine cowl:


The bamboo skewer is from a hamburger I had last night. Don't you just love all this free stuff!

I opened up the air scoop and rounded out a trough in B7 and drilled a hole in B8. I will place a proper sized plastic tube between the 2 holes to make a fully enclosed receiving tube for my prop stop. I plan on putting 2 stops for each prop as I am unsure which position I will prefer. Extra weight is fwd of cg anyway.

As I said before my props will rotate in the same direction. Winding the starboard motor with more power than the port motor. With thrust line to the right and down.

FYI: I just weighted all the fuselages. standard P-38 is 22g, lightened P-38 is 19g, lighted FW 190 is 13g. The P-38 twin fuselages are about 6 inches longer than the Focke-Wulf.

Mitch