So, I had some free time today, and decided to build a DIY cooler for my Meade 2080. After some Googling, I figured I didn't have the expertise or skill to build something like the Lymax cooler, but I did find some great articles, and one that caught my attention was Piotr Maliński's blog post about how he built a blow-through cooler. Here is his link: http://www.rkblog.rk...ade-sct-cooler/
The idea is simple: hook a 12V fan up to the visual back, and remove the screws around the primary mirror casing that would be used for mounting a dovetail bar or other accessories. The fan will draw air into the OTA and it will vent out the screw holes. I asked my son if he had any derelict PC's laying around, and he provided me a 12V DC 3 inch chassis fan. I then dug up a car accessory cable that had been chewed by my cat (meow!) and hooked the two together. Plugging it into my power pack, I verified the fan runs fine.
I then went to the hardware store with $10 and came home with two parts from the plumbing area:
- 3 x 1 1/2 ABS reducer
- 1 1/2 x 1 1/4 adapter
That's it! Went back home and hooked them all together with black duct tape. I added a used dryer sheet to the back of the fan to keep dust and debris out of the OTA and hooked it up. PRESTO! A steady stream of air from the 6 screw holes around the back of the OTA. I would expect this will reduce the cool-down times of my scope, and all it cost me was $10 and some effort.
I'll let y'all know how it works out.