Folding GWS Props?

go to

and do a search for 'folding props'. LOTS of them there!

Right. For speed 400 and larger sized motors -- not for little bitty indoor/outdoor GWS drive systems.

Unless you know of > go to

and do a search for 'folding props'. LOTS of them > there!

Tim Wescott wrote in news: snipped-for-privacy@corp.supernews.com:

Should have noticed this thread earlier. I have that same kit, sitting on the shelf, and every couple of months I look at it and think, "Oh, that would make a neat little electric RC . . ." So, are you running it on 1 or

2 cells (lipo, I assume). And what radio?

-Mark

It uses a GWS 4-channel receiver, HS-55 servos, a Castle Creations Pixie-7 speed control and a GWS IPS 'A' gearbox with an 8x4.3 prop. The

650mAh LiPo's are just a bit too big to fit in the fuselage as I built it, so it has a 7-cell 330mAh NiMH. I think I could get the LiPo's to fit if I stripped off the heat-shrink and dressed the pack a bit (that's what I did to get the NiMH pack to fit).

Flying weight as built is 7.1oz. On a 7-cell NiMH pack it's a bit underpowered for me, which will probably translate into a _lot_ underpowered for a normal person (I like realistic flyers).

I think I'm going to get one of the Fiagio brushless motors for it, possibly after experimenting a bit with props. If I were starting out fresh I'd look at some of the really small outrunners that are coming on the market, and ditch the gearbox entirely.

Comet kits tend to have heavy wood and antiquated design features. I made the following modifications to the kit:

• All of the long, strong wood (spars, longerons) is from the kit. Comet kit wood is almost as good as spruce that way.

• Some other parts (wing ribs and fuselage uprights) I made from lighter wood. I should have been much more aggressive about that.

• Get a postal scale or a high-school lab scale, weigh every piece of wood, and think about how much load it must carry. I did that on my next plane and it worked better than filling it with helium.

• Since I was cutting my own ribs I split the spar in half & made it an I-beam section. This gives you much more strength right where you need it.

• The wing tips are laminated from 4 1/32" strips, to get a lighter, stronger tip than the Comet method. I got a SIG Bag-o-balsa that had a bunch of 1/4" x 1/32" wood, which made it easy. I cut a form out of some double-thick corregated cardboard, covered the business end with some really ugly orange Econocoat (tm), soaked the wood in ammonia overnight one day & pinned it against the form to dry the next -- the day after that I glued it with Amberoid 'cause Amberoid's easy to sand.

• The stab outline is cut from plywood made from thin sheet glued with Ambroid. It's much easier to make than it sounds and it's light light light. I don't know why you can't just buy the stuff it's so cool.

• The nose is significantly shortened; I basically just chopped it off at the first former in from the nose, made a plywood ring to fit what was left and faired it a bit with some 1/8" balsa.

Some mistakes I made were:

• I should have used my own, smaller trailing edges while I was at it.

3/4" trailing edges on a 5" chord wing, and heavy wood at that, is just stupid. I'd use 1/2" or even 3/8", and I'd go with medium wood instead of the Balsa going on Oak that Comet sells.

• Ditto for leading edges, maybe. That's what hits the fences and tree branches; I've had a couple of such events with no visible damage except to the tissue.

• Tissue! Boy does that stuff bring back memories, particularly when you're doping it. Amazing how you forget what something as mild as dry grass does to it when you land, though. Think twice before you use it (but I like mine).

• I used the Comet design center section, and built it last. Boy what a mistake. I'm not sure what the right answer is, but following the kit isn't. Making that notch in the rear center section is a challenge that Comet didn't exactly rise to.

• The plane started as an attempt at rubber-powered RC. It was way too heavy for that (which is why I now weigh everything). I converted it to electric at a time of high stress in my job, and I simply could not get motivated to plan ahead so I painted myself into a few corners (like the battery fit). Had I had the battery and motor sitting on the plans when I built the fuselage it would have gone better -- but then I would have had to plan ahead & would never have gotten it done.

Tim Wescott wrote in news: snipped-for-privacy@corp.supernews.com:

Okay, I won't quote the whole description of how you adapted it. But thanks - I saved it for reference when (if) I get to that project. I'm thinking more like a 4.5-5 oz takeoff weight, with LiPos and smaller servos. Might use the same motor (IPS) - I agree that the brushless would be better, but I've been flying other planes around 5 oz with the IPS and the power has been okay, so I'll save the brushless motors for planes that can actually use the power. At least at first - I reserve the right to change my mind.

P.S. - since you mentioned the Feigao - I have one, on a cute little profile plane with 137 sq in of wing and just under 7 oz takeoff. I'm running it on a 3-cell lipo and it's *quite* perky.

can't help you. A tip. As you're landing, leave the motor turning over slightly. less drag.

I just changed the prop to a 8x6 last night and it perked right up. I was flying it today to find out how much motor run I'd get -- at 5 minutes 30 seconds it got stuck in a tree :(, so now I've got to figure out how to get it down.

That is wrong. You need 9x7 on A drive on 7-8 cells or 2s LIPO

Use 7x6 for 3s LIPO and its about 80% more powerful. Can use 8x4.3 also but its very draggy when windmilling, and very low top speed.

The

You an get 350 or 450 LIPOS that will fit.

Go 3s LIPO first. Way more power and as long as you prop back to a 7x6 it will be reliable.

If you are anywhere on Katrinas track, just wait till she gets it down for you :-)

Nope, I'm in Oregon -- but we did have severe thundershowers out here in the Portland area. I found it right before dinner time lying up against my shop. It's pretty broken up so I just ripped the electronics out and popped them into a warm oven to dry them out ASAP. I'll probably just build another plane.

I forgot to mention -- I split the vertical stab in half for the rudder, and it wasn't enough for a big propeller and slow flight. I had to add about 30% more area to the rudder before that worked right. If I rebuild the thing I'll just go straight up from the center of the vertical stab for a BIG rudder.