A little while ago, on a lark, I ordered a 113mm eyepiece from Surplus Shed, because I was ordering some refractor objectives and bearings to make a Crayford focuser at the same time, and I was curious about an eyepiece with such a long focal length.
Last year, I picked up a Meade DS-16. It was a large, bulky telescope of early 80s vintage. Using it was like wrestling with a dead elephant; it had a clock drive for tracking RA, but no fine controls at all, so aiming it precisely was very difficult. On top of that, the tube didn’t rotate at all, so it was really easy to get the telescope into impossible positions. When the telescope was pointing south, it was very difficult to look through the eyepiece. I had to stand on a stool and the mount to be able to get a look through it, because using a ladder didn’t help at all (the ladder got me higher, but it didn’t really get me any closer).
This was not an ideal situation, but it was tolerable until the thing fell on me while I was taking it out of the garage. I escaped serious injury, but decided enough was enough. It was time to convert the beast to a Dobsonian that would be easier to use and that I’d be able to take to Mt. Rainier or Mt. St. Helens.
Below the fold are more pictures of the Dob at different stages of building, and some discussion of how I built it.
Since I’m very close to finishing up observing all the Messier objects (I have seven left at the moment, which I have to wait on getting back into the sky before I can go looking for them), I’ve started looking for more obscure objects, like I did the last time I went out. The sky’s a big place, though, and it can be hard to decide what to look for among the NGC or other catalog objects.
Back in late 2010, I built a very small split ring telescope. Split ring telescope examples are out there on the internet (and here’s another example), but they’re a lot bigger than the one I built. Building a split ring mount for a 3” telescope was both easier and more difficult than building a larger one, since on one hand I didn’t have to work with huge things, but on the other working on such a small scale meant I didn’t have a whole lot of room to work.