Installation of Kendrick's secondary heater on GSO 8" RC

The moment I saw this kit from Kendrick Astro Instruments, I bought it. What was attracting me the most, is the option to install it so that the wires won't protrude into the optical path. They supply thin adhessive copper ribon that you can run along the sides of the spider vanes instead of running wires. I'm going to use that copper ribbon and I have some other idea on how to power it and be able to close the lid without fiddling with wires.

I have placed the heater on it's place on the back of the secondary housing and cut the wires just enough to rich one of the spider vanes.

For the power connector I decided to use two pin screw type plug/socket which will assure that it won't disconnect accidently while telescope is tracking during the night. The base plug will be installed permamently on the telescope's body.

Very accurately, with the OTA pointing down I drilled 10mm hole on the base of the telescope in line with one of the spider vanes.

From inside you can see that I have drilled the hole exacly between the baffle walls. The height of the plug that I'm going to isntall should be lower than those walls so it won't intruduce itself into the light path.

To connect the plug with the copper ribbon I have drilled a hole in a baffle wall, just small enough for the wires.

Wires were soldered in position 90 degrees to the socket. Those two pins were higher than the baffle wall, so after soldering I filed them down just a bit to the desired height.

 

 

Here you can see the socket installed and wires were cut just long enough to reach the spider vane.

 

 

A view from the outside. Looks very neat.

 

 

On the first image you can see red VHB adhessive tape from 3M that I have planned to use with the heater strip. But I have found that it is best to use silicon glue as recommended by Kendrick.

 

 

 

Left it for 24 hours for silicon to dry out.

 

 

 

The copper adhessive ribbon is just genious. It's very easy to work with, it's very thin and in a matter of couple of minutes it were sticked to the spider vane and soldered on both ends with the wires.

 

 

 

This is the view of the other side of the spider vane. Just rolled over the OTA and repeated the process of placing the copper ribbon and soldering it with the wires.

 

 

 

Here is the view from the front, to show, how low profile this job really is. Nothing is intruding to the light path and more important, that all four spider vanes will remain with the same thickness.

 

 

 

The final touch is to paint copper ribbons with black paint to minimize the possibiliy of unwanted reflections.

 

 

 

And final result. The outside threaded plug is firmly connected to the OTA's body and dew controller.

 

 

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