Capstan Servo

[Roger_Peterson]

The cable retaining clamp that fits around the capstan drive to keep the cable on the pulley is set at right angles to the mount. When the capstan drive is placed directly above the cable it is driving, the small capstan cable rubs on the edge of the retaining clamp. Would it not be better to place this clamp at 45 deg to stop any rubbing.

 

[dynonsupport]

Rubbing is bad, but I'm not quite visualizing it. Can you post a picture?

 

[Roger_Peterson]

 

[Roger_Peterson]

As you can see if I rotate the capstan cable retainer bracket 45 deg, it would not rub the cable at all.

 

[davedubb]

Can you move the servo up by 1/4" or so. I do not think it would be a good idea to remove the retainer from the critical area where the cable enters the capstan. The slight angle of the cable that would result should not have an effect on the performance of the autopilot.

-David

 

[Roger_Peterson]

Can you move the servo up by 1/4" or so.  I do not think it would be a good idea to remove the retainer from the critical area where the cable enters the capstan. The slight angle of the cable that would result should not have an effect on the performance of the autopilot.

I was not considering removing the Capstan Cable retainer, just rotating it 45% to stop it from rubbing on the cable. If I were to raise the servo up, it would only rub more.

 

[Roger_Peterson]

Capstan Servo Instalation PA11

[/img]Attached Photo of a Capstan Servo Installation In a Piper PA11 replica.

 

[paxhia]

I am using the capstan servo's, looking at your picture, the bracket looks closer to the capstan than mine. On my servo the distance between the capstan and the bridle cable is just under the diameter of the cable, so the cable doesnt pop off. Give support a call and give the the spacing from bracket to capstan to confirm yours was mfg correctly.

 

[davedubb]

Let me look into this when I get back into the office on Monday. My first guess is that something is installed correctly or you have a defective bracket because the cable should not rub against the bracket or the capstan when installed. I don't have a capstan servo at home so I can not verify this until Monday. I would like to state again that the retaining bracket positioned at the entry point of the cables in critical to the safety of the installation. This is the location where the cable is most likely to depart the capstan if there is slack allowed in the cable.

 

[Roger_Peterson]

Thanks, Appreciate it.

 

[davedubb]

Can you send me a wider shot of the installation. I am interested in how you have the cable clamps installed. It would be nice if you can include a ruler in the shot for dimensional reference.

 

[davedubb]

Thanks but the picture does not show me the white plastic cable clamps used to attach the servo cable to the control cable. What I am trying to determine is what orientation the cable clamps are installed at. The cable clamps should provide about 1/4" separation between the two cables where they are attached and should be installed in the same plane (vertical in your application) as the servo enclosure body.

 

[Roger_Peterson]

I added a modified fairlead to keep the cables in a constant position. The bell crank had been causing too much movement and therefore some rubbing. Right now neither cable rubs on the capstan cable guide.

 

[davedubb]

We are happy things are working for you now. Feel free to contact us anytime if you have further questions.