MGL Capstan Kit Range of Motion

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James.Lent
Posts: 2
Joined: Thu Apr 15, 2021 4:33 pm

MGL Capstan Kit Range of Motion

Post by James.Lent »

Based on the instructions I found here:
https://www.mglavionics.co.za/Docs/caps ... nstall.pdf

The capstan kit is limited to 350 degrees of rotation, but I haven't been able to find what that actually results in for a total cable throw. I don't have the kit in hand, otherwise I'd just measure the diameter of the capstan. Does anyone know the total cable throw?

Thanks for your help!
rainier
Site Admin
Posts: 701
Joined: Fri Aug 28, 2020 7:03 pm

Re: MGL Capstan Kit Range of Motion

Post by rainier »

Total usable travel about 10cm. That's 5cm either way from midpoint.
That's for the actual active range the AP can control.
You can add another 10cm or more each way at least for manual control. If this is the case the limitation is that the AP should be engaged when the controls are neutral (more or less). During typical AP operation the stick does not tend to move a lot. You will need to evaluate this on a case by case bases.
Should the AP be engaged while the drum is in the incorrect rotation the AP will not be able to function correctly.
James.Lent
Posts: 2
Joined: Thu Apr 15, 2021 4:33 pm

Re: MGL Capstan Kit Range of Motion

Post by James.Lent »

Thanks Rainier. I've got a followup question. The capstan is thicker than the arm it replaces, but doesn't come with a new shear screw. As a result, insufficient threads are exposed. At best, I'm getting 1 thread engaged, which is obviously nowhere near enough for a secure attachment. Is there a longer shear screw I should be using? I'm hesitant to improvise here since this is a critical component of the fail safe system.

In the attached photo it LOOKS like there are 3-4 threads, but thanks to the lip on the side, only 0-1 can actually engage with the collar.
20211020_141417.jpg
20211020_141417.jpg (251.97 KiB) Viewed 4797 times
rainier
Site Admin
Posts: 701
Joined: Fri Aug 28, 2020 7:03 pm

Re: MGL Capstan Kit Range of Motion

Post by rainier »

You can fit a longer screw or even countersink the hole a bit deeper.
We like using brass screws here as they have just the perfect properties for this application but you can use a stainless screw as well.
It is M3 thread.
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