C14 Rebuild/Modification

I have been chasing the mirror "Drift" gremlin for quite some time. After all my testing and modifications to date, I was still experiencing the drift that caused oblong stars in 3 min. when guiding with an external guidescope. I use an Andy Homeyer Scope Cradle to hold my C14, and have a refractor mounted on each side. When I use the same guidescope, but guide the refractor, I get no drift and my stars are round after 30 min exposures. The only thing I thought could still be moving was the C14 mirror, and due to the design of this SCT, about the only thing left to tighten was the spanner nut on the front of the mirror. To do this I needed to make a wrench, and take the scope apart. I decided that since I was going this far, I would do some additional modifications at the same time. I added cooling fans, flocked the inside of the OTA, regreased the baffle tube, added an inside temperature sensor, and and gave everything a good cleaning. I will run my star compare test again after the mods to see if I stopped the mirror movement. Following are the pictures of the mod process.

	Same as when I first installed the Software Bisque locking collar,when the wife is supportive, life is good :-). My operating location was again the kitchen table.		Just as before, the first piece out is the corrector. I removed the retaining ring and made note of the position of the cork spaces. Also, I noted the position of the number on the corrector. Taking a picture is an easy way to return it to exactly the same orientation.
	I have spacers at the top, bottom, and right side. I used masking tape to label the locations so each could be returned to its original position.		With the corrector removed, I carefully collected the spacers and taped and labeled them to a popsicle stick so they wouldn't get lost.
	Here is the scope with the corrector removed . You can see the 3 markers for the spacer locations.		I started the project by cutting the holes in the rear cell for the 3 fans that I would use for cooling the big mirror.
	A view from the inside. The fans will be mounted 120°apart. All metal hardware will be painted flat black.		A power connector was installed to bring 12Vdc to the fans that are installed on the inside of the OTA.
	All fans are mounted and wired. Two fans will blow in and one will blow out. I decided to use 90mm fans as I wanted to keep the size of the holes I drilled small while still supplying ample CFM for cooling.		Here is a view from the back. The intake grills are doubled and sandwiched in between each is an extra filter cut from a vacuum cleaner bag. This will help keep the fine dust out.
	The next thing I added was an indoor/outdoor thermometer to let me watch the temperature inside the OTA. The temp probe is shown in the botom right of the picture.		Here is a closer view showing that I attached the probe to one screw of the carrying handle. This will measure the air temp behind the mirror.
	This shows the reading from the thermometer. The "OUT" is the temp probe that will be behind the mirror.		My next modification was flocking the inside of the OTA. I used ProtoStar flocking paper and cut it close to fitting first. Then as the backing was rolled off, I used a piece of PVC pipe to roll the paper flat, then trimmed the excess.
	Here is a view of the inside of the OTA after the flocking was completed. The inside is much darker now and there is less reflected light.		Next came a new coat of Dow Corning High Vacuum grease. The mirror baffle was run up and down a few times and then the excess greas was wiped off.
	I tightened the spanner nut about 1/3 of a turn as it seemed pretty loose. The mirror was cleaned and the Software Bisque collar is back on.		Reassembly is started and the project was completed the next afternoon after work.