· Get a Cloudy Nights T-Shirt · Submit a Review / Article Click here if you are having trouble logging into the forums Privacy Policy | Please read our Terms of Service | Signup and Troubleshooting FAQ | Problems? PM a Red or a Green Gu… uh, User You are not logged in. [Login] Entrance · Main Index · Search · New user · Who's Online FAQ · Calendar Equipment Discussions >> Classic Telescopes Previous   Index   Next   Threaded   Pages: 1 Jason H. Pooh-Bah Reged: 11/23/07 Loc: Central Florida Sloppy Meade 2080 SCT secondary, way to fix it?       #5241611 - 05/27/12 01:13 AM Edit   Reply   Quote Quick Reply   Hi Guys, Question regarding Meade 2080 8" SC, the secondary is kind of floppy, are there springs in there by the 3 hex screws and is there a way to stiffen it up? Also, the corrector plate seems to have a little play in it relative to the cork spacers, is this normal? Thanks in advance for any help, Jason H. Post Extras:       Bill Griffith sage Reged: 08/12/09 Loc: Ca. Re: Sloppy Meade 2080 SCT secondary, way to fix it? [Re: Jason H.]       #5242217 - 05/27/12 01:13 PM Edit   Reply   Quote Quick Reply   Jason, Absolutely no springs. The secondary mirror is attached with a thin set epoxy (I believe) onto an aluminum round disc with three holes threaded that match the 120 degree spacing on the outside counter-bored plastic cover. The aluminum plate also has a center drilled hole (conical shaped) that receives a cone shape (pointy thing) that the secondary assy. gimbals on. The possibility is you may have socket headed cap screws that are too long and bottom out before securing. Note: Securing is a not quite an accurate description. I adjust in collimation with these screws to barely finger type. I have some minimal lateral play in my corrector (old cork). The corrector is clocked in the original position and uses that tolerance to co-axially align the optical system. 2080's have only one collimation point. The retainer ring and the button headed cap screws keep the corrector gently in place. Keep in mind pinched optics can wreak havoc!! Lastly, I'm not an expert and it has been a while since I have had mine apart. I should just say, "No springs". Bill Post Extras:       Jason H. Pooh-Bah Reged: 11/23/07 Loc: Central Florida Re: Sloppy Meade 2080 SCT secondary, way to fix it? [Re: Bill Griffith]       #5242437 - 05/27/12 03:44 PM Edit   Reply   Quote Quick Reply   Thank you very much Bill!!! Your reply makes a lot of sense, basically I'll pivot the secondary mirror, making sure there's no slack, but not over tightened either (seems tricky because one could easily have slack on one screw and perhaps not know it until the scope is moved?) I think it should have had springs, but I guess there must have been an engineering reason why they didn't do that (eventual spring-metal fatigue?) Regarding the corrector plate, luckily the creator put a white dot of paint to assure proper alignment in the future, and it was shifted/rotated somewhat from the original. I think we'll improvise an additional spacer by each of the pieces of cork to prevent lateral motion, taking care to have the secondary exactly centered (as it was off too) diminishing the need to over-tighten the corrector plate retaining ring (which apparently was tight to keep it from moving, but that didn't prevent the lateral slip of the plate.) Thanks again very much! Jason H. Post Extras:       rmollise Postmaster Reged: 07/06/07 Re: Sloppy Meade 2080 SCT secondary, way to fix it? [Re: Jason H.]       #5243379 - 05/28/12 08:14 AM Edit   Reply   Quote Quick Reply   Springs are really not necessary. You have the secondary on a pivot. The screws are threaded into their holes. If they are properly tightened, there is never a problem. The secret? Always collimate by _tightening_ screws. Only when one is snug should you loosen opposite numbers to continue turning the original screw in the desired directon. If the other screws are snug, one being a little loose will have no effect. Floppiness will only come from all screws being loose. Post Extras:       Jason H. Pooh-Bah Reged: 11/23/07 Loc: Central Florida Re: Sloppy Meade 2080 SCT secondary, way to fix it? [Re: rmollise]       #5244862 - 05/28/12 11:04 PM Edit   Reply   Quote Quick Reply   Thanks Uncle Rod!!! I was hoping you, having a lot of SCT know-how (or maybe Tim having worked at Meade?) would see this post. Regards, Jason W. Higley Post Extras:       Pages: 1 Previous   Index   Next   Threaded   Extra information 5 registered and 9 anonymous users are browsing this forum. 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