Spoiler retraction

[SOH]

Good morning,

I have some cable activated spoilers that I want to ensure stay close when not needed. I could use rubber bands or magnets but I was wondering if someone might have an "elegant" way of doing this.

Thanks,
Steve

[kwmtrubrit]

If your spoilers are directly linked to your servo(s) by the cable, that should be enough to hold your spoilers closed. Do you have one servo controling both (wing mounted or in the fuselage), or does each spoiler have its own servo in the wing? I have a GL with one servo in the centre of the wing with cables going to the spoilers. No magnets or bands. If the cable isn't in an outer sleeve to prevent slop, you may need to have something to keep them closed. Having said that, lots of flyers rely on air pressure to do that job. Launching might be the only time they may pop open (not a good time I agree). Do a search as there is a thread where someone used springs.

Keith

[SOH]

The servos are connected to the spoilers by cable, running in a sleeve, in a pull to open configuration, therefore there is no tension on the cable when they are closed. I have noticed that at times they don't close all the way. The tension on the cable has not changed as far as I can tell. You do bring up a point to check. I wonder if the sleeve might be expanding with temperature? This would tension the cable. Also I want to make sure they stay closed on launch. I have one servo controlling both spoilers.

Steve

[Curare]

I'll take a photo of the spring mechanism in the spoilers of my Sag if you like.

It's almost too simple but has worked effectively for years

[kwmtrubrit]

The servos are connected to the spoilers by cable, running in a sleeve, in a pull to open configuration, therefore there is no tension on the cable when they are closed. I have noticed that at times they don't close all the way. The tension on the cable has not changed as far as I can tell. You do bring up a point to check. I wonder if the sleeve might be expanding with temperature? This would tension the cable. Also I want to make sure they stay closed on launch. I have one servo controlling both spoilers.

Steve

Do you have a computer radio? That will give you fine tuning on the trimming of the cable via the servo. The other thing that could be happening is the outer sleve isn't being held rigid enough. When you close the spoiler, there's flex in the cable (inner and outer) so any tension in the hinging of the spoiler holds it open.

Keith

[SOH]

I believe what is happening is like kwmtrubrit says. The tension of the hinge tape is holding it open slightly. I have checked for enough slack in the cable when they are closed. Just one of those annoying little things.
Thanks for the ideas.

Curare, I would appreciate the pics of your set up. Might be something I would like to try.

Steve