Can someone clarify how the braiding step works into Hodes' Rubber Motor Excel Worksheet from freeflight.org Technical Library? I'm trying to merge info from several articles and youtube videos, and just want to make sure I'm thinking correctly. (I've worked through these calculations by hand, then discovered Hodes' worksheet, so I'm giving that a try now because I'm done thinking so hard, as I'm a "recovering engineer."

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I'm attempting to revive a 90% complete Comet Stinson SR-7 that I started in early 2000s, and recently found and pulled out of the basement. I've been studying some of the info about braiding rubber motors, so I am familiar with the basic methods, advantages, etc.

I found the great intro articles at freeflight.org Technical Library for rubber motor sizing, braiding, number of windings, as well as Hodes' Rubber Motor Excel Worksheet for download.

Going through Hodes' worksheet, I plugged in what I know, and estimated the airplane weight (see attached- I hope it's viewable). Some of my numbers might be off at this point (I don't have a scale), etc.

Hodes' worksheet tells me I need 122 inches total of 1/8" rubber strip. Then, to get 1.75x the prop Hook-to-Peg distance (1.75 is just a whim based on what I've read, and to get the number of strands to be an even number), I'd need to use 6 strands of the 1/8" rubber, each at 20.1 inches long,

**BEFORE BRAIDING**.

I now have 122 inches of 1/8" rubber, folded into 6 equal length strands (in theory, I don't have any rubber in-house yet). Each strand is ~20.1 inches long.

My main question:Based on the articles I've read, in order to braid it from this point, I think I would take those 6 strands at 20.1 inches long, unfold them into 3 strands at 40.2 inches long, then start the braiding process from there. So I would next take the 3 strands, twist about 4-5 turns per inch into them, then fold the ends over to double them up to get the final 6 braided strands. IS THIS CORRECT?

So, due to the braiding, the 6 strands will end up a bit shorter than the 1.75x the Hook-to-Peg length, which is nice because it takes up some slack I guess

Question 2:How do I know that there will still be tension on the rubber once it unwinds after flight, and not be too long? One of the advantages of braiding is that it is supposed to keep the prop pulled into the nose during flight after the rubber's energy is spent, as I understand.

Thanks for any thoughts.

Matt