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col.....
Hi mbaddah - yeah, anyone with a sense of adventure who actually wants to "know/understand" the "guts" of collimating will do what you did: plenty won't and they'll never really get to first base with collimating: don't panic though, it'll work out!
That central bolt/screw on the secondary doesn't loosen/tighten as such (unless you go beyond the limits of its' intended adjusting - but you would have known when you fiddled around to mis-collimate the scope, if that had happened.)
Presuming you didn't (despite what I said in my opening sentence) actually go to the masochist's stage of buggerising around with the spider vane adjusters on the scope - then the most likely real problem is your playing with that central screw/bolt.
That's the gizmo that moves the secondary mirror up and down the tube, it's spring-loaded and that's why I said in normal situations you don't refer to its' adjustments as "tightening" or "loosening."
Before I go any further - I presume that you have the instruction sheet that came with the Orion sight tube/collimator?
My first suggestion is to back off the 3 screws set at 120 degrees apart on the sec back - if you need to move the sec down the tube/truss towards the primary this is not necessary but if you need to go "up" away from the primary you'll need to do it - so do it anyways!
Then by just looking straight down the focusser tube (no Orion in but trying to centre your head/eyeball over the open tube) see if the sec mirror surface is fully visible: if it aint adjust that central sec bolt/screw to push or pull it into a roughly central position relative to the bottom end of the focusser tibe.
When you've got a rough set on this drop the Orion in, and looking through its sight hole refine the process - only this time you will be seeing the bottom end of the Orion tool as the reference circle that you need to get the secondary mirror centralized in, as opposed to the bottom end of the focusser tube when you did the preceding "rough" set (and you won't be worrying now about your head/eyeball position.)
A word of caution - if you find that you needed to move the sec "up" by screwing that central bolt/screw clockwise, just keep checking that there is still space underneath the 3 setscrews: cos the sec holder will impinge upon them if you don't make sure there is space for the mirror and holder to move "backwards" - and then you might "bend" one of them etc.
Finally, when you reckon that the sec mirror looks centralized in the bottom end of the Orion, and still with a tiny bit of slack in the aforementioned 3 screws, reach in with one hand, being carefull not to touch the actual sec mirror surface, and physically rotate the sec until, still peering down the Orion, the oval sec mirror looks as if it is circular (which of course it aint, but looking down the Orion you should be able to twist/turn the sec with one hand untill it appears perfectly concentric within the Orion's bottom end.)
Then (and it gets like the octopus analogy, especially if you haven't installed "bob's knobs") pinch up the 3 secondary screws just enough such that you can take your hand away from holding the sec mirror and it should stay in the position you held it in.
Then it's time to adjust the secondary's tilt using those 3 screws as per general instructions. I find doing this inside with the ol' sheet of A4 lightly taped to the inside of the tube opposite the focusser, and with the open end of scope pointing at a white wall, and a light shining onto the cutaway of the Orion tool facilitates the whole shebang.
Cheers, Darryl.
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