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Found various threads on here and other forums about flocking dobsonians/newtonians but couldn't find specific images of disassembly of the very popular SkyWatcher Heritage 130p flextube and flocking of the OTA.
So having ordered some DC-Fix black velour sticky back material (can be got from various places including FLO) I thought i'd share some photos of the process from start to finish as it may help someone else in the future...
Images below with notes...
1. Focuser and shield flocking
This was the easy bit. A strip stuck inside the focuser, and just unscrew the shield, draw round it, cut the material and align and smooth down. In the last image above you can already see the significant improvement on reducing reflections comparing the flocked shield to the unflocked tube...
Notice my version of Bob's Knobs on the secondary mirror which are just black steel M4 25mm knurled thumbscrews bought off ebay for about £7 - along with the thumbscrews already on the 130P primary mirror this makes any fine collimation easy and completely tool free!
For full stealth mode I've also painted the edge and rear of the secondary mirror, and any exposed screw heads with blackboard paint to reduce reflections.
2. OTA disassembly and tube before
Note the cutout in the lower primary housing and the top ring. This aligns with the ridge of the tube seam, and means there is only one way to reassemble the telescope tube and mirror and one place for the handful of screws (4 at the bottom, 3 at the top). You'll also need an allen key to remove the 3 bolts for the dovetail mount. Simple!
Now you're ready to Flock 'N' Roll! 👍🏻
3. Flocking the tube
You'll need approx. 50cmx29cm of the material to do the tube in one go, starting along the seam. As others have described just take your time here, peel off about an inch of the backing and get the edge aligned with the tube seam stick down firmly and smooth out any air bubbles.
Then slowly keep peeling more backing (rip and remove if the excess gets in the way) and smooth down as you go, turning the tube and affixing the velour material.
4. Finished flocking and close up during application so you can see contrast/reflection comparison of before and after.
All in all only took around an hour so not a hard job as long as you prepare and concentrate! I ordered one sheet of 45cm x 1m material which was plenty, however if your not as confident you'll get it right first time then order 2m so you have more to spare if you need to start again.
Looks great, so as always I now just need clear skies to go play and see the difference it makes!
I am thinking on grinding my own lightweight mirror (first f4 16", later f4 24"). The lightest and cheapest option is to get a thin blank and slump it in a decent kiln.
Anyone has longer term experiene with slumped mirrors? Overall doesn't seem to be more work than a normal (not pregenerated) blank.
Do I have to grind the backside as in case of normal flat back mirrors to avoid astigmatism? How do people support a convex back while grinding? Does it make sense to grind a hole in the middle for additional support? I am remotely considering a convertible Newtonian/Cassegrain system anyway...
Looking for a 12" DOB (or larger) which can be transported to Prestwick, Ayrshire. Any brand, as long as the telescope is optically sound and in good working order. I'm a reliable buyer who has bought and sold on this site before.
Looking to upgrade from my current 4.5" EQ reflector to an 8" Dob.
Not particularly concerned with brand and don't mind used condition provided all is in good working order.
Bundled accessories are a bonus (EPs and filters especially) though not a must.
Based in North Wiltshire and happy to drive to collect within reasonable distance (<1hr30).