From: Flying Bluegill <flyingbluegill@...>
Date: Tuesday, June 30, 2015 12:11 PM
Subject: Re: [BugHLG] Launching
Date: Tuesday, June 30, 2015 12:11 PM
Subject: Re: [BugHLG] Launching
John
Could you be kind enough to point me to this "silicone rubber" that you ordered from Hobby King?
perhaps a link, or an item number on Hobby King's site
I have looked on the website, even searched for it, to no avail
thanks
Joe M
From: "gldrgidr@... [BugHLG]"
To: BugHLG@yahoogroups.com
Sent: Tuesday, June 30, 2015 11:02 AM
Subject: Re: [BugHLG] Launching
You can only be right if the rubber remains stretched at the point of release. I've seen this happen in strong winds but most of the time, the height reached isn't going to be more than the length of the rubber combined with the length of the string. You could probably add more string with silicone rubber so maybe that would get you more launch height.
After the wear and tear of 15 years of hand launching and DLG, my body appreciates that I minimize the steps needed to launch.
Even with that, I'm curious enough that I just ordered the silicone rubber from HobbyKing. With shipping from the east coast warehouse the cost was a bit over $11.
John
- Joshua Finn joshuawfinn@... [BugHLG]
- Today at 10:13 AM
- BugHLG@yahoogroups.com
Truth of the matter is that if you can stretch the silicone twice as far as the usual stuff and still get the same force, the model will go significantly higher. Launch energy is directly proportional to spring constant, but is proportional to the square of the stretch distance. I fly free flight gliders competitively, and the stretchier rubber definitely provides an altitude advantage. It's also lower stress--the stretchier rubber has a slightly slower acceleration, but being over a longer distance, gets you going faster in the end.
On Mon, Jun 29, 2015 at 10:21 PM, gldrgidr@... [BugHLG] <BugHLG@yahoogroups.com> wrote:
I haven't tested this but I have heard it from others. Normal rubber stretches about three times it's length. Silicone stretches about 6 times it's length to give the same pull. This means that you have to pull the silicone high start back twice as far to get the same height. I'm 65 and I tend to choose less effort over more. There's also a matter of needing a longer field. But you can't beat the price!
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