weird yet potentially lovely little Tak mount
Posted 01 December 2010 - 05:44 PM
It's an absolutely gorgeous little mount. (Or will be when I'm finished with it.) The trouble I'm referring to stems from the way that it assembles. Two conical screw heads project from the dec / counterweight bar assembly which you insert into two corresponding holes in the clock drive / R.A. assembly and then tighten it using nearly microscopic (and I'm not exaggerating that at *all*) set screws through the side of the clock drive using an allen key that I actually believe I could swallow without ill effect. (Although obviously I don't recommend that.) The declination bearing is attached to the counterweight bar in the same ridiculous manner.
There's no problem assembling it that way, except that those tiny set screws can't possibly keep the thing together under any load. When I put my old Brandon 80mm on it (about 6 pounds with rings and a plate) it works quite well until I actually move the scope, at which point one or both of the referred to attachment points will simply pop loose, pretty much immediately.
No particular problem, I plan to simply replace the conical head screws with ordinary round head ones with big enough heads (with washers, if necessary) to cover the entirety of the holes that they insert into and thus make the whole assembly permanent. Should be a simple fix that works extremely well, but what I can't understand is how anybody ever expected this arrangement to work in the first place. (Or how there haven't been any complaints about it.) Anyone?
Posted 01 December 2010 - 07:10 PM
Posted 01 December 2010 - 07:21 PM
Posted 01 December 2010 - 10:24 PM
Posted 01 December 2010 - 10:31 PM
Posted 01 December 2010 - 10:36 PM
Posted 02 December 2010 - 11:12 AM
Posted 02 December 2010 - 11:16 AM
Posted 02 December 2010 - 01:09 PM
You might want to contact Art at TNR and ask him about the mount. Maybe you're doing something wrong, and if not, he'll let Tak know the product has problems.
Posted 03 December 2010 - 06:13 PM
The threads were quite easy to match up in a local bolt shop, mine turned out to be M5 x 20's. I used socket heads with M6 flat zinc washers. If you put the washers on upside down and really tighten, they'll taper themselves a little and you get a bit of the self-centering back. Again, not ideal but a distinct improvement. Hope it works for you, too.
Posted 03 December 2010 - 06:15 PM
Posted 04 December 2010 - 02:20 PM
Posted 05 December 2010 - 05:28 PM
Note the tiny set screw near the slow motion. THAT's what's supposed to have supported everything...
Posted 05 December 2010 - 06:02 PM
Posted 06 December 2010 - 02:09 PM
Posted 06 December 2010 - 02:43 PM