stunthanger.com
Speed,Combat,Scale,Racing => Scale Models => Topic started by: Jim Carter on April 02, 2015, 09:05:45 AM
-
Greetings! I've written to the AMA Safety Coordinator for his thoughts and now I'd like to put this forth to those more knowledgeable than me. I am writing this seeking recommendations / rules concerning the use of a product specifically Sullivan kevlar cable. This product is rated at 100 pounds which seems to exceed the requirements written in the scale rules. I am in the process of building a control line B-29 and although I know that most of types of control line planes use either solid music wire or your stranded cable, I would like your thoughts on using the kevlar cables in place of the other options. Being as this is a four engine (.25 c.i.) which should end up, I'm guessing, in the 6-10 pound range, ready to fly, I believe the actual pull test will be in the 40-50 pound range. As such, the kevlar cable would well exceed the appropriate test range. It would be my intention to use a length of the Sullivan Gold-N-Rod inner sheath to enclose the two leadout cables exiting from the fuselage to the wing tip to minimize the possibilities of fraying and direct handling. I do not, repeat, do not intend to use the kevlar lines for actual flying, just as leadouts. Thank you in advance as I look forward to your responses.
-
Jim. my only experience with Kevlar is as a pull-pull system on the tailwheel of a pretty big R/C B-17. It failed during the first taxi trial. It can be cut very easily by any little burr on the horns. I have never used it for anything since.
Chuck
-
I do not, repeat, do not intend to use the kevlar lines for actual flying, just as leadouts.
[/quote]
You WILL be using them for actual flying. That being said, I don't believe the rule book is specific about the material requirements for leadouts, only that the system be strong enough. I am wondering why you would want to do this.
-
Thanks Chuck! Thanks Bill! I was just hoping this would be a suitable substitute as it's something I already had on hand. I ran out of the .021 and .027 cables and forgot to reorder. So now I guess I'll just wait for my order for heavier steel leadout cables arrives from Brodak.