P-40 DRIVER

Here is a picture as things stand today. All the stringers are in place and she is on her gear.



Next we start the wing

P-40 DRIVER

Ok, we have made progress on the Cub despite some setbacks. I managed to hack my arm up when a 30cc gas plane attacked me. No permanent damage but a reminder not to forget your safety procedures.

P-40 DRIVER

I decide to go with An ASP .61 for power on this project; simple, cheap which is in keeping with the theme of this project. One of the ideas of this project was to end up with a plane one would actually have to fly.

P-40 DRIVER

The spinner will disappear in favor of a spinner nut. I'm also experimenting with a MA 13-5 prop. we will see how that works out. I need the most thrust I can get, and that should do the trick by keeping the engine rpm's in it's power band. A 12oz dubro gas tank will carry the fuel. The engine mount is a Great Planes 60-120 adjustable. I've also decided to go with Hitec 485's on the tail and 422's for the wing and throttle. Battery is still up in the air as I continue to experiment. I have ditched the pushrods for 4-40 rods in tubes and gone to Dubro hardware where needed.

buzzard bait

Man, sorry about your accident! Thanks for posting that...we all need all the reminders we can get.

I think the 13x5 prop choice will be perfect. A 13x4 would work too.

A 14x4 might work too, but the load on the engine would be significantly higher, so might not be good for the engine, but if it works without over-heating I'm sure it would fly the plane. I fly a 4 Star 60 on an OS 70 with a 14x4; of course the OS 70 is fine with it, but the point is that even with only 4 inches of pitch and 9600 rpm there is plenty of speed to fly the plane, and it's no Cub.

In case you need any non-yellow color schemes, here are a few I've collected. Not that it has to be a model of any particular airplane.

Jim

P-40 DRIVER

buzzard bait: Thanks for the info, I like those alternative schemes, and I appreciate the confirmation on the prop choice.

P-40 DRIVER

On with the show. I started the center section which is per plan except I deleted the window and servo mount. I have switched to mostly CA here to speed things up, with wood glue being used on the plywood/ balsa joints.

cubcrasher

My Feedback: (6)

P-40, that arm looks nasty. Your cub will fly just fine with that engine, might need a little
nose weight. The first 1/4 cub I built was a clipped-wing powered with a K&B 65 sportster.


Buzzard bait, those are some nice cub photos. I found that blue one on line a couple years ago. I
printed it off and it has been hanging on the wall ever since.

P-40 DRIVER

Cub Crasher: Thanks for the confirmation, I think it should be fine too, if I can get this thing in at 12 pounds.

P-40 DRIVER

I started the wing which is per plan except that it does not have any dihedral which simplifies the building process. I don't like the aileron horn setup so that will probably change to what, I don't know yet. Building a 7 foot+ wing on my five foot table setup is going to require some juggling but should be fine. I'm running a Two aileron servo setup in the wing.

TomCrump

I've built a few one piece wings that were longer than my building board.

With a wing, such as yours, just center it on the board, when you join the halves. Taking out the dihedral makes it easy.

When dihedral comes into the picture, I make sure that the root ribs are set at the proper angle, and go for it. It may not be scientific, but it works,

buzzard bait

A Cub should have a little dihedral. It's not much, but if it's not there it won't look like a Cub. Or was no dihedral a mod to the clipped wing version? I didn't pick up on the clipped wing part till I saw that the wing was to be about 7 feet, and thought, that's 1/5th scale, and then checked the title.

So I'm glad people liked the photos, but they are of full span Cubs. There are lots more non-yellow clip wing schemes out there.

Jim

P-40 DRIVER

buzzard bait: Taking the dihedral out of the wing was to make the plane a little less stable and it makes it easier to build as well. I agree that the airplane does loose a little in the looks department though.

do335a

Having built several of these Cubs and several more of the wings - funny how that happens - and having flown them off land and water (that must be how I wound up making more wings than complete planes), I can assure you that the minor amount of dihedral in the wing does not compromise its aerobatic ability and does not increase the difficulty in building the wing.

With the dihedral, the plane flies very well inverted on floats and stays where you put it until you command a change.

I also agree with buzzard. Without the dihedral, it just does not look right.

It actually would help you, since your bench is only 5' in length. Each panel is quite short and stubby, being considerably shorter than 5'. The center section and the tip, which does not need a table for support, are added later following the completion of the outer panels. That leaves you with plenty of room on a 5' table.

Although I've always used an O.S. 1.08 with 15-8 wood prop to overpower, if I do another, the engine of choice will most likely be an OS 1.60 FX. There's nothing like a clipped wing Cub on steroids and the Sig 1/4 scale version is a great candidate for that.

kmeyers

That arm is a story. Is there a place hear where you could tell it (out of this thread)?
Hope you have a speedy and full recovery.

I love cubs.

Great work so far. Great thread.

I don't think that a tiny bash on the Sig 1/4 scale will change much. It won't hurt anything though.

But, your idea of detail simplicity should reduce the build time.

A good redesign that would take advantage of modern ideas and materials needs to be done. With some cross section reduction as well.

One of the best flying cubs I have is the little PNP 81" H9. It is just over 5 lbs and hovers on a good .46 glow. Very interesting design.

My Sig 1/4 scale is 16 lbs and hovers near the end of fuel on the ST 3250 in the nose. I have the clipped wing for it too but have never flown that wing.

I had two of those Giles 202's. First with a ST 2300, then a ST 2300 on a pump.

Keep up the build updates please and thanks for the pics.

P-40 DRIVER

do335a: Its to late for me to put the dihedral in at this point. I have built several cubs without it and really have not noticed much positive or negative from the mod. I'm not even saving much time either, but it seems I've headed down that road on this one too so maybe next time. Where my table is located currently is more of an issue then its size, may have to move it when I build the other wing panel.

kmeyers: There is a story to that Giles 202 and my arm, but I did not figure it was appropriate for this thread except to mention. The arm is healed now, and except for a scare and a little nerve damage around the wound area, I should be 100% as time goes on.

I'm kind of going against a lot of conventions; on this build, to show you can end up with nice flyable airplane without spending a bunch of money. Keeping the weight/ complexity down allows for all the systems to be lighter and cheaper which makes the whole plane lighter and cheaper. I don't like ARF's, and this allows me to experiment and modify at will. The other thing, is to make the plane as low maintenance; out of the box, as possible. I hate having to fix stuff because I did not build it right in the first place.

P-40 DRIVER

I picked up a roll of clear Monokote which I may use for the side windows. the jury is still out on that one though. I also hope to get some more work done on this plane over the Thanksgiving weekend.

R/C Art

My Feedback: (38)

I have used clear Monocote for windows on a Robin Hood 80 and was very pleased with the result. I say go for it.

cubcrasher

My Feedback: (6)

I like to use small screws on the windows. The inside cabin of the cub is pretty
big but sometimes it sure is nice to stick your hand through the side to get to something.

cubcrasher

My Feedback: (6)

Here's a shot of them.

P-40 DRIVER

R/C Art: thanks for the confirmation, That's an idea I heard of and used on an old 40 size Bud Nosen Champ I built.

cubcrasher: That's a good idea for easy access, nice looking plane, what are you using for servos?

cubcrasher

My Feedback: (6)

Thanks man, I have a futaba 3010 on the rudder and 3004's everywhere else. The elevator
has a servo on each half.

P-40 DRIVER

cubcrasher: Sounds like we are in the same place with the servos, thanks

P-40 DRIVER

Started building my wood cowl using the plastic cowl in the kit as a pattern. This will allow me to Monokote it instead of paint. Saves me from buying a fiberglass cowl and associated paint products. This worked out extremely well on my Goldberg cub so I thought I would do it here as well. Photos are self explanatory, but if you have questions let me know.

P-40 DRIVER

More photos