stunthanger.com
Building Tips and technical articles. => 1/2 A building. => Topic started by: Motorman on July 11, 2019, 10:25:43 AM
-
blank
-
I think it is going to have to have a lot less wood in it than a Cub. And be a lot lighter. How thick is the airfoil? Are you willing to go without landing gear? Even if you are, remember the line drag is dominant. Fifty-two foot lines are long, even if they are .008's.
Something you might find helpful, or simply enjoy reading would be Rich Porter's Model Aviation articles on his Ridiculous 1/2A stunt planes. Been a long time since I've read them, but as I recall, his whole schtick was to make the biggest 1/2A plane possible using the TeeDee, tuned to do patterns. It lead to some interesting layouts....
Hope you come up with something you want to give a try,
The Divot
-
Look up the aeromaniacs site. There's a half-A stunter in there that flies exceedingly well on a Norvel 061.
-
Looking at 300 sq in wings for 1/2a stunt and found the Cub. I was thinking of getting a rib set, making a light profile fuselage and generally stripping down any extra weight. Do you think an 061 would pull it on 52' lines?
Thanks,
Motorman 8)
Hi Motorman, Yes, a strong .061cu" will fly a model on 52' x .012" lines. Also you might be able to
construct a simple built up box fuselage that is significantly lighter than a profile fuselage.
As a case in point, I built a "Lil Duper Zilch" (400sq" wing) from plans that I strengthened the 3/32"
sheet sides with 1/64" sheet plywood. the complete ready to fly model weighed 14ozs sans fuel,
powered by an MVVS 2.49cc plain bearing diesel engine. I sold it to a friend(to buy a Southern Mountain BP rifle);
that friend sold or gave it to another friend, and that's the last I could trace it. D>K
Tony G :)
-
Sad to hear the kit is so bad. When one goes together right, it is one of the best small models I have ever flown.
Next time get a SkySport from RSM. Easy construction, Eric insists on good wood and appropriate hardware.
-
Dude, lighten up, my 1/2a Pathfinder flies great with a OS 10, 2 oz hayes tank, 52 foot lines and a wing tab on it!! n~
-
Hey guys, the MM has what he has. If he can't fix it, or if he says it's not worth fixing, then I for one want to see the video of the balsa chips coming out the chute on the rotary mower. Be sure to get hi-res video. Hundred twenty frame rate if you can so that we can have some good slomo.
I've fixed a lot of planes, but frankly, some of 'em just weren't worth it. Someday I'll learn to tell which ones are and which ones aren't....
The Divot
-
D-tube. Same wing as the Pinto and SkySport. Easy to build, strong and very warp resistant.
-
MM is right about the 1/2A Pathfinder in that the wing is a pain in the ass to build...lots of parts,but they do fly well. Chris Fretz did a fine job with his at Brodaks. I've still not finished mine ,but it is well along the way. Regarding the Pinto,a first class 1/2A model,and yes it is strong! Cheers,PhillySkip
-
I have a Pathfinder hanging on the wall waiting to be covered. The wing is still straight as an arrow after hanging for 2 years. I'll be sure to take care when covering it to avoid introducing a warp. Mine is set up for aa Norvel Big Mig .061
-
400sq at 14 oz is really good. I had one of those MVVS 2.49 on a Mercury Midge. It liked allot of pitch in the prop.
Right now I'm building a 1/2a Pathfinder. This kit was a total waste of $70. It's got a million ribs and allot of lumber in the wing but it's still very easy to twist. bad design that's weird to put together. Half the parts aren't made right, all the ribs had cut outs for the landing gear and had to be filled. the wood selection is terrible, the fuselage is 3/8" balsahogany, one flap is punk the other rock hard, same with elevator, line slider is useless by design, the weight box weights more than you would want empty, massive bellcrank, have to replace allot of wood. Other than that it's great.
Motorman 8)
Hi Motorman, I had the same reaction to the Brodak 1/2A Pathfinder kit as you did.
I bought the kit several years ago, because it seemed to be a decent design and I
thought it should be easy to keep the RTF weight around 11oz. I intended to power
it with a Paw .8cc sbr diesel(that's .049cu"). Sorry guys, but to me, a Half A engine
stops being a Half A at .0501 cu". An .061cu"engine is a small "A" class. But then,
that attitude comes from flying years of 1/2A FF, Speed, Combat and 1/2A racing events.
Anyway, when I weighed the kit wood, it weighed a total of 16oz. That meant I would have
to replace nearly all the wood in the kit. So, I just put the kit aside until much later.
The last modified Ringmaster Jr. I built and flew, revealed that the 195sq" wing area
was too small for the kind of power generated by the Paw .049 sbr. That's why I liked the
1/2A Pathfinder design at 236sq"s wing area. Barry Baxter has flown several excellent performing
240sq"-250sq" models powered by a Paw.049 TBR diesel. Well, I'll kit bash that Pathfinder
in the near future. D>K
Tony G :)
-
you should chat with Core House Phil Cartier
-
If someone came out with a 250 sq. in. foam wing for 1/2a I'd be on it like a duck on a June bug.
Motorman 8)
Hi Motorman, If wing weight is a consideration for you; a built up balsa wing is lighter than
a foam wing. We found that even using a foam LE on a built up balsa wing, the finished wing
was lighter than the foam wings that we used for Combat flying. Tony G S?P
-
Phil 1/2 a wing is 235 he. Could might cut one bigger
-
The Barecat has about 350 sq in. Weight is 15oz or less and will fly on 52 ft .008wire lines.
Howard
-
Go to Gallery, search on Barecat.
Yes, I used Bob Baron's color scheme.
It does fly great, best to have a pit man that understands bladders.
Roger