We finally had some reasonably warm weather over the weekend and it wasn't ridiculous humidity, so I was able to to a little more work finally (but no pics).
Primed the lower tube rings and put on a base flat black coat. If the weather is decent this weekend, I'll get the wrinkle finish on them. Also primed and repainted the spider. That leads me to a couple of questions.
1. I cannot use the Criterion secondary because it's too small for the f/5 optics, so I bought a larger one. It adjusts differently from the Criterion secondary. The Criterion uses a "pull" system, where the adjusting screws go into threaded holes in the secondary holder and tightening the screws pulls the secondary holder in. The central bolt fits into a "pivot" hole in the secondary holder for movement. The new secondary holder is a "push" type. By that I mean the screw thread into a ring and as you tighten the screws, they push on the secondary holder for adjustment. So far so good. I keep going back and forth with which way I'll go (push or pull). BUT... the real question here that I need some help with:
The central mounting threaded rod is threaded into the secondary holder. There is no means for pivoting. Should I not need to worry about this because of the small movements necessary to collimate the secondary? Or should I countersink the backside of the mounting piece and use a tapered bolt in the countersunk hole to allow more freedom of movement (if I use the "push" method)? I am looking for opinions here. If I elect the "pull" method, I can plug the threaded "through" hole and create a pivot surface - that's not an issue for me. I guess I'm wondering if there is a preferred method, push or pull? I've got a little time before I need to commit, but I'm trying to get on this.
2. I need to clean the primary mirror and have read some threads about this, but haven't come across a clear methodology. There seems to be reasonable consensus to use 90% distilled water, 10% alcohol, with a drop of dish detergent. So far so good. Do I just drop the mirror in the solution and let it soak? Should I pour the solution over the mirror to carry away whatever ick is on it? Again, I've got a little time to work this out, so I thought I'd ask the collective here.
I'm really close to finishing this thing. I'm sending the Sky Micro body to a friend with a CNC mill and he's going to make my adapter for me for the cost of materials. I want to have everything else pretty much finished when it gets back.
Once I clean the mirror, I'll install it in the OTA as well as the finder and the spider. By around the same time I hope to have the secondary holder figured out and finished, so I'm waiting on is the adapter for the Sky Micro. I'll have to paint both and straighten the shaft on the focuer, but that shouldn't be a big deal, assuming favorable weather. I also need to drill the holes in the bolts to clamp the two halves of the tube rings together. In theory this is easy, but the brass work-hardens very quickly, so I have to put together a fixture to hold the bolts under some ATF while I'm drilling to get nice holes without breaking drill bits.
Anyway, thanks to all following along and looking forward to y'all's opinions regarding questions 1 & 2.