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Jul 05, 2019, 03:28 PM
A man with a plan
Balsaworkbench's Avatar
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64 down, 32 to go.
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Jul 05, 2019, 10:14 PM
A man with a plan
Balsaworkbench's Avatar
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Well, there you have it. 96 cap strips. It's probably not worth a photo at this point because the wings are still ugly. I'm going to shape the leading edges, join the halves, and fill in the center sheeting. Then I'll take a photo.
Jul 07, 2019, 01:41 PM
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FWW - I enjoy seeing photos of each step because they always convey ideas.
Jul 07, 2019, 02:24 PM
A man with a plan
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Well, I can't argue with that. Here are a few photos of one wing. The other five look exactly the same. The joints at the ends of the cap strips are still rough. The bottom of the leading edge stick was sanded to allow the wing to rest flat on the table during the addition of the shear webs.

I've decided to use up some old scraps of trailing edge stock for wing tips.
Jul 07, 2019, 02:51 PM
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Much obliged!
I struggle with sanding the "root rib area" so that wing halfs perfectly touch without gaps. When you get to that stage, would love more info. around what you did and how it turned out.
Jul 07, 2019, 03:46 PM
A man with a plan
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It helps if you use a long sanding bar and fresh, coarse sand paper.
Jul 19, 2019, 12:03 AM
A man with a plan
Balsaworkbench's Avatar
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I'm joining the wings now. I added wing tips made of trailing edge stock, then shaped the leading edges and sanded off any protruding lumps. I weighed the six pieces and found that two were 2.4 oz, two were 2.6 and two were 2.8. Fortunately they were matched in left-right pairs.

So far I have two sets joined, and the last is clamped right now as it dries. The two that are already joined have pretty good lateral balance.
Aug 14, 2019, 06:28 PM
A man with a plan
Balsaworkbench's Avatar
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It's been a while, but I'm getting back to it. I made 4 sets of aileron torque rods, three for this project, and one for the other 20 size plane I'm working on at the moment.
Aug 18, 2019, 12:47 PM
This is kid stuff.
Mazzepa1's Avatar
There's something I'll remember.
Start checking, and compensating for, lateral balance as early as possible in the process rather than waiting until the finishing stage of equipment placement.
1. My plane will be laterally balanced before covering.

You've probably got a list of such maxims on your website, don't you?

I hate adding dead weight with a passion, and lead on the wingtip of a completed plane is the worst. A testimony to my lack of skill as a builder, even though I can still play the beginner card.
Helps aid righteous flying if my airplane and I both look good.
Aug 18, 2019, 01:53 PM
A man with a plan
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I have a list of things you should remember to do before it's too late, such as attaching the blind nuts to the back of the firewall before the nose section is closed. I learned that the hard way.

If your ribs are of various densities, you can arrange them so the strongest ones are in the center and one at the tip, and put the softer ones midspan. On my planes the ribs were very soft and very hard, so I alternated them. I matched the spars in pairs by weight.

I learned my lesson a long time ago, by building a wing that was so far out of balance that I had to glue a whole bunch of pennies in one tip.

I think building three planes at once makes it a little bit easier. When I form the ailerons I will probably have some significant variety in weight, so I can put the heaviest pair on the lightest wing, and vice versa. I'm hoping the finished weight of the three planes will be as similar as possible for easy formation flying.
Aug 19, 2019, 07:01 AM
The runway used to be longer
Mad_Mike's Avatar
Quote:
Originally Posted by Balsaworkbench
easy formation flying.
Can't wait to see that video.
Aug 19, 2019, 10:39 AM
This is kid stuff.
Mazzepa1's Avatar
Formation flying is not easy.
I too look froward to seeing that video.
Aug 19, 2019, 03:56 PM
Registered User
I'm glad to hear I'm not the only one who does stuff like weighing wing ribs, spars, etc. I felt slightly silly doing it, but hey, it's a hobby and it's part of the fun, whether it makes much difference in the flying or not.

I do like the way light weight models fly, so I try to get lots of small weight savings to add up.
Aug 19, 2019, 04:58 PM
A man with a plan
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I have mixed feelings about weight savings. I prefer lightweight airplanes, and I prefer to use smaller servos, batteries and engines when possible. I also choose light wood where it will be effective. But I don't like swiss-cheesing the living daylights out of structural parts. A guy sent me a set of files to cut out parts for a 60 size plane. The laser makes easy work of punching hundreds of little holes. When it was all finished the parts looked like lace doilies. I gathered all the little discs and weighed them. He saved half an ounce on a 60 size plane and cut the strength in half.

But I do like saving a little bit of weight when I can, and I would rather not have to put weights inside one wing tip.
Aug 19, 2019, 09:26 PM
Registered User
I don't do the holes. It cuts across grain and reduces strength, without, as you point out, reducing weight very much. I think it's much better to choose wood carefully, take advantage of grain direction to gain strength, and consider how much structure is really necessary.

The holes make the frameworks look like full scale structures, but that is deceptive. On WWI era planes, where wood was used, holes were made in ribs, but the edges of each hole were reinforced with vertical grain splints. In other cases, usually later designs, holes were made in metal, which doesn't have much grain to it, or ply, which has grain running in two directions.

There is no point in just putting holes in sheet balsa, and it doesn't correspond to anything real aircraft designers did.


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