Building Tips and technical articles. => 1/2 A building. => Topic started by: Motorman on January 11, 2020, 03:37:13 PM

Title: Best Wing Construction for 1/2a
Post by: Motorman on January 11, 2020, 03:37:13 PM
Title: Re: Best Wing Construction for 1/2a
Post by: 944_Jim on January 11, 2020, 10:59:36 PM

No real input from me, but I'm dying to know where you are going with this. That is a big wing for a little engine.
You may want to look at the wing construction of the Pinto. I think it is almost as big as what you are proposing. Also look back several months here. There was a really sweet ME-109 (or was it the FW-190?) done almost as big. I think it was the guy that did a balsa clone of Cox plastic Spitfire, and the Clone Top Flite Bearcat.
Title: Re: Best Wing Construction for 1/2a
Post by: Dave Hull on January 12, 2020, 12:59:47 AM

In your previous thread where you asked about largest wing areas, I referred to a my largest 1/2A stunter, which I call the Spring Break Special, because that is when I built it during college. It has 201 in^2, with a 6-5/8" root, 6" tip and uses a solid LE and TE, no planking, 1/16" ribs spaced nominally on 2" centers. The covering sag is not that much, and it saved a ton of complexity and work. As you can imagine, I was in a hurry with only a week off.

On the other hand, I have an OPP (Other People's Plane) awaiting completion that is a bit smaller, but is basically constructed just like a Nobler wing, except the main gear is in the wing. The ribs are 1/32", as are the cap strips, the LE planking, and the upper and lower TE sheeting. The spars are 1/8" square. The ribs are spaced at 1" centers. It is not covered yet, so I don't know what the covering might do to it (Starved Horse) but it has no noticeable ripples in the finished planking. Tissue would not be a problem, but polyspan and dope might be. I believe you said you were not a fan of the Baby Pathfinder, so a "Mini-Nobler" would probably not be a fun exercise, either. But these wood sizes are suitable if you can work with something more fragile. I don't have a weight comparison with the Spring Break Special, so can't help there. But I'm sure the SBS survived a couple of crashes over grass while other guys tried it out, whereas the Baby Nobler construction might not.

Hope you keep chugging on this project. Will be interesting to see how it turns out....

Title: Re: Best Wing Construction for 1/2a
Post by: Brett Buck on January 27, 2020, 11:06:00 PM
What would you consider the easiest most effective construction for a 250 sq. in. 1/2a wing. They say foam is too heavy and warren truss requires all kinds of foam cradles and bucks, lots of work. That leaves straight ribs so the question is leading edge sheeting or lots of 1/2 ribs. I'd like to do leading edge sheeting but do you think 1/32" balsa is thick enough for 1-1/2" rib spacing?

   I built several 1/2As that size that were foam-cored and sheeted with 1/32 balsa. It's not too heavy.

Title: Re: Best Wing Construction for 1/2a
Post by: Bob Hunt on February 04, 2020, 11:04:40 AM
Back when the Tercel and the Sunspot (among other 1/2A designs...) came out, I sold dozens of foam cores and covered foam wings. The weight penalty of a covered foam 1/2A wing is almost negligible compared to a built-up wing.

Lately I've made several 1/2A wing Lost-Foam fixture sets as well. Either method - if done properly - works extremely well to make a 1/2A wing.

Later- Bob Hunt
Title: Re: Best Wing Construction for 1/2a
Post by: Fredvon4 on February 04, 2020, 12:53:02 PM
many of the very capable winning 1/2a fast combat wings are solid foam....Core house Phil Cartier cuts good wings...
harder to get Jeff Dawson makes n sell some awesome sonic chicken and other variants

motorman pm me an address I will send a selection of both foam dust here
Title: Re: Best Wing Construction for 1/2a
Post by: ray copeland on April 01, 2021, 02:23:07 PM
What is the total weight with engine , wheels and tank. I am using Sig Akromaster plans for my next 1/2a, trying to keep it around 10 ounces. n~
Title: Re: Best Wing Construction for 1/2a
Post by: Phil J on May 20, 2021, 04:07:41 PM
I prefer to build I-Beam wings  Here is a picture of a 1/2A Stiletto I'm working on completing current weight 7.5 oz. 
Title: Re: Best Wing Construction for 1/2a
Post by: kevin king on May 25, 2021, 06:39:19 PM
Nice job on the Thundergazer too Motorman 👍