· 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 >> Reflectors Previous   Index   Next   Threaded   Pages: 1 | 2 | (show all) bobmarleyou812 sage Reged: 01/18/08 Loc: CA How to split a dob       #4673963 - 07/04/11 05:54 PM Attachment (48 downloads) Edit   Reply   Quote Quick Reply   About a year ago I decided to split my solid tube 14" Discovery dobsonian because transportation was very cumbersome. I acquired a set of brackets from a fellow who was converting his split tube Discovery to a truss design. Here is my story. Post Extras:       bobmarleyou812 sage Reged: 01/18/08 Loc: CA Re: How to split a dob [Re: bobmarleyou812]       #4673966 - 07/04/11 05:55 PM Attachment (42 downloads) Edit   Reply   Quote Quick Reply   first thing was to remove the primary and secondary mirrors Post Extras:       bobmarleyou812 sage Reged: 01/18/08 Loc: CA Re: How to split a dob [Re: bobmarleyou812]       #4673971 - 07/04/11 05:56 PM Attachment (39 downloads) Edit   Reply   Quote Quick Reply   very careful not to drop the primary Post Extras:       bobmarleyou812 sage Reged: 01/18/08 Loc: CA Re: How to split a dob [Re: bobmarleyou812]       #4673974 - 07/04/11 05:57 PM Attachment (30 downloads) Edit   Reply   Quote Quick Reply   now the secondary Post Extras:       bobmarleyou812 sage Reged: 01/18/08 Loc: CA Re: How to split a dob [Re: bobmarleyou812]       #4673975 - 07/04/11 05:59 PM Attachment (29 downloads) Edit   Reply   Quote Quick Reply   now that the fragile pieces are removed, I propped the tube up onto two saw horses. To prevent the tube from rolling off while I was working, I taped 4 baseballs to the saw horses. Post Extras:       bobmarleyou812 sage Reged: 01/18/08 Loc: CA Re: How to split a dob [Re: bobmarleyou812]       #4673981 - 07/04/11 06:00 PM Attachment (30 downloads) Edit   Reply   Quote Quick Reply   next thing was to snap a chalk line where I wanted to brackets to go. I did this to ensure they would line up properly after installed. Post Extras:       bobmarleyou812 sage Reged: 01/18/08 Loc: CA Re: How to split a dob [Re: bobmarleyou812]       #4673986 - 07/04/11 06:02 PM Attachment (32 downloads) Edit   Reply   Quote Quick Reply   now I lined up the brackets and drilled holes along the chalk line. Post Extras:       bobmarleyou812 sage Reged: 01/18/08 Loc: CA Re: How to split a dob [Re: bobmarleyou812]       #4673989 - 07/04/11 06:03 PM Attachment (33 downloads) Edit   Reply   Quote Quick Reply   now it was time to do some actual cutting. To ensure I cut in a straight line, I taped some pieces of graph paper together and wrapped it around the tube. I lined up the same line of the first graph paper with the last. Post Extras:       bobmarleyou812 sage Reged: 01/18/08 Loc: CA Re: How to split a dob [Re: bobmarleyou812]       #4673990 - 07/04/11 06:04 PM Attachment (32 downloads) Edit   Reply   Quote Quick Reply   lining up the graph paper Post Extras:       bobmarleyou812 sage Reged: 01/18/08 Loc: CA Re: How to split a dob [Re: bobmarleyou812]       #4673994 - 07/04/11 06:07 PM Attachment (34 downloads) Edit   Reply   Quote Quick Reply   now I picked the height I wanted to cut. I decided ahead of time I wanted the base and bottom tube combined to be the same height as the top tube. Post Extras:       bobmarleyou812 sage Reged: 01/18/08 Loc: CA Re: How to split a dob [Re: bobmarleyou812]       #4673996 - 07/04/11 06:09 PM Attachment (37 downloads) Edit   Reply   Quote Quick Reply   after about 5 razor blades and some sore fingers the tube was almost cut in half. I propped an adjustable chair in the middle to keep it from falling off the saw horses after it was fully cut. then I separated the two ends. Post Extras:       bobmarleyou812 sage Reged: 01/18/08 Loc: CA Re: How to split a dob [Re: bobmarleyou812]       #4674003 - 07/04/11 06:12 PM Attachment (43 downloads) Edit   Reply   Quote Quick Reply   now that the tube was cut, it was time to clean up the edges. The cut was far from perfect so I purchased some edge molding from an RV dealer at the auction site. I think it was $1 a foot and well worth the cost. It can also be purchased from West Marine, but at higher cost. at this time I also bolted the brackets in place, pinching the edge molding to prevent it from falling off. Post Extras:       bobmarleyou812 sage Reged: 01/18/08 Loc: CA Re: How to split a dob [Re: bobmarleyou812]       #4674007 - 07/04/11 06:13 PM Attachment (31 downloads) Edit   Reply   Quote Quick Reply   next I attached some carrying handles purchased from Home Depot Post Extras:       bobmarleyou812 sage Reged: 01/18/08 Loc: CA Re: How to split a dob [Re: bobmarleyou812]       #4674012 - 07/04/11 06:15 PM Attachment (29 downloads) Edit   Reply   Quote Quick Reply   Now it was time to reinstall the mirrors. I painted all the inside hardware on the secondary and brackets with flat black paint to prevent glaring. Post Extras:       bobmarleyou812 sage Reged: 01/18/08 Loc: CA Re: How to split a dob [Re: bobmarleyou812]       #4674016 - 07/04/11 06:16 PM Attachment (48 downloads) Edit   Reply   Quote Quick Reply   give it a good collimation and go to the desert and look at some stars! Post Extras:       bobmarleyou812 sage Reged: 01/18/08 Loc: CA Re: How to split a dob [Re: bobmarleyou812]       #4674026 - 07/04/11 06:21 PM Edit   Reply   Quote Quick Reply   After a year I must say I'm truly happy with this decision. The total cost was around $100. that included the second hand brackets, razor blades, carrying handles, and edge trim molding. Transportation is much less cumbersome now that the dob comes apart in 3 pieces. Collimation is not effected very much by disassembly. Post Extras:       jz02879 sage Reged: 12/02/10 Loc: North East PA Re: How to split a dob [Re: bobmarleyou812]       #4674066 - 07/04/11 06:41 PM Edit   Reply   Quote Quick Reply   Wow, nice! I wish I had the skills and confidence to mod my scopes like you. Post Extras:       Dick Jacobson scholastic sledgehammer Reged: 12/22/06 Loc: Plymouth, Minnesota, USA Re: How to split a dob [Re: jz02879]       #4674475 - 07/04/11 10:56 PM Edit   Reply   Quote Quick Reply   Very nice job! I also split my 14" Discovery several years ago. I made a line with white crayon, laid the scope on the floor on some 2x4s, and used an ordinary carpenter's saw to slowly cut around it, keeping the blade almost tangential to the tube. The result came out very smooth, almost perfectly straight. I did not put any kind of trim on the cut edges and used the scope for 5 or 6 years with no problems. Eventually I rebuilt it as a truss and am still tinkering with it today. Post Extras:       Tom Andrews Pooh-Bah Reged: 01/25/07 Loc: Albuquerque, NM Re: How to split a dob [Re: Dick Jacobson]       #4674534 - 07/04/11 11:46 PM Attachment (31 downloads) Edit   Reply   Quote Quick Reply   Very nice job! It looks just like the split-tube I bought. Post Extras:       cavefrog Carpal Tunnel Reged: 11/11/08 Loc: loozyanna Re: How to split a dob [Re: Tom Andrews]       #4674590 - 07/05/11 12:32 AM Edit   Reply   Quote Quick Reply   Post Extras:       Pages: 1 | 2 | (show all) Previous   Index   Next   Threaded   Extra information 12 registered and 27 anonymous users are browsing this forum. 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