Well after much stuffing around and going in circles, I finally finished something, so here is my guide cam mount. Next thing will be a pc controlled focuser, any suggestions anyone.
Jason,
while I am insanely jealous at your metal working abilities, I do seriously wonder about a sprung pin as one of your three points. The one thing that will snag your operation is any form of flexure, and while the rings are more robust than necessary, the weak link "may" be the sprung pins. I like to adjust the three screws I use and tighten then tight.
Gary
Cheers guys thats just the sort of advice i need (<---Noob) I have made the springs quite strong and the knobs take a firm twist to move. but now that you have pointed that out im not so sure. I may have just made a very strange paperweight. Hopefully i will sort the software tonight and get to test on sat.
If springs are strong enough, there will be no flexure.
And it is much easier to manipulate 2 instead of three knobs... at least, the scope is always fixed with constant pressure (determined by springs).
I am planning to have similar design (with springs) and I do not see a problem.
Try and see..
No paper weight Jason. If the springs don't work out, just tap three more holes on each ring 30° on from the first ones (oh and where the spring support contacts ) and make two more threaded adjusters.
Jason,
please don't take my comment as a criticism, and if it works, even better.
The main concern with any off axis or separate guiding system is flexure, or differential flexure, between the imaging system and the guiding system. If there is any shift between them it shows as poor guiding, blobby or elongated stars etc. Try yours, and if it works, I will be the first to congratulate you. And if it doesn't, simply modify what is already an impressive piece of engineering.
Gary
I'm sure you could also make your own using a stepper motor and USB interface kit (I think Jaycar has these type of things). I have both the JMI and Orion motors and can post some pics if you want.
Unfortunatly testing of the guide cam was delayed by another noob mistake, it seems i am getting to the weight limit of my Heq5 with the 2 scopes and the DSLR. I am considering adding another counterweight of about 2kg. I did however get to try out my new $26 sealed lead acid battery, which worked a treat. and gave me 5 hours of trouble free running last night.
Hey thanks Peter for those examples of some focusers. I was considering makeing my own. But that little Orion focus motor looks good.and i imagine i could make a long cable run to the pc and just use the supplied controler.
I made a long cable initially - you need some 4 core phone wire with 4 pin RJ11 connectors on each end. You can also purchase longer cables - they are the type that connects the handset to the telephone.
The reason I went for the shoestring controller is because it enables you to make very small pulse movements of the motor that are much finer than you can achieve with the hand controller on the slowest speed.