18 aileron cove rib attach angles, primed, drilled and ready to assemble into the scrap bin. Made them from .032 instead of .025. Moral of the story, RTFP, read the fu***** print.
Gerry
Patrol #30
"if you can't fix it, feature it" The world's first .032 pocket rib angle equipped patrol, one of a kind!
I am sorry. But hey at least they're small. Sounds like you didn't rivet them to the spar yet, also a nice save.
...fun fact: the Model B plans indicate the aileron pocket ribs should be .020. I didn't read the plans close enough and made them with .025. I'm planning to use them as-built. Perhaps.032 will be just fine!
Karl
Bearhawk Bravo #1508B - Scratch Build (wings)
Northern Idaho
How much square footage of .032 we talking about, vs how much time to remake them? .032 is somewhere around .44 lbs/sq foot. .025 would be around.36, just mental math in public. Saving weight is close to number one for me. But how much sq footage are we talking about, vs the time to remake them.
How hard is it to change them out later? I think they are external. I think my choice would be to press on. My rear seat frame is untouched, and a couple of things like the floorboards are not what I want. I think I can make much lighter cargo doors. But they are easy remedies, later. I would rather get er done. If I have some down time, maybe I will do them before I fly, but they are not priorities.
By my estimation, in rough numbers, the total sheet areas for all the pocket ribs is on the order of ~1.7 SF. Using the unit weights provided by sylvo, the difference in weight by going from .025 to .032 pocket ribs would be an increase of about 0.136 pounds (assuming the math is correct...I'm an engineering, so I could easily be wrong...). Seems like a strong argument to stay with the heavier-duty as-built ribs....
Karl
Bearhawk Bravo #1508B - Scratch Build (wings)
Northern Idaho
I get it, but it's just a two day setback. Not much in the grand scheme. Maybe I can repurpose these parts in the flaps/aileron structure. I won't be able to change them affer they are installed on the aileron cove. I know that at the end of the build compromises will be made. I just want to get there with an airframe as light as I can make it and per print. Onward.
Gerry
Patrol #30
The final tally on remaking the cove rib attach angles out of .025 vs .032 turned out to be 1.53 ounces. The structure is back to print and I can reuse the .032 attach angles in the flaps. Pretty happy with that weight savings. The weight goes in by the pound and comes out by the ounce.
Gerry
Patrol #30
Hey man, just rib angles! Believe me, this is the list quantity. I think I throw away 1/3 of all aileron and flap ribs and ext. what was made from sheet metal because of some reasons(wrong thickness, cracks, wrong size, ext.) I think there is no worry about feeding the garbage bin. Just think light, build light!
Hey Olm, I like the way you think. "Just think light, build light". Thats great, can I use that? Whats it like scratch building in Russia? How do you get raw stock, hardware etc?
Gerry
Patrol #30 tandem
Hi Gerry, that's not mine, the phrase is Tony Bingelis' from "The Sportplane Builder"(recomend this book!). I think scratch building in Russia is the same with America, also takes a lot of time🤣. We use local material, which is much cheeper, aluminium and stainless steel instead 4130. And I think orders from Aircraftspruce come a little longer.
Oleg
Comment