maxwolfie
05-07-2010, 06:00 PM
Here's some pics from today. I'm loosely following this (http://www.astunit.com/tonkinsastro/atm/projects/scotch.htm) guide. It's all very much "experimental" at the moment, many things will no doubt change. An M6 nut wedged into a 10mm hole seems to be working quite well, actually. The nut moves pretty freely as the rod enters at various angles, but it does not move forward or backwards (at least without a lot of force). Open to ideas though. Obviously I need to chop down the threaded rod. I might do that last though :)
http://img412.imageshack.us/img412/3667/firstday1of7.jpg
I used 2 x nuts and 2 x washers along with some heatshrink to "lock" the rod's position to the base hinge.
http://img31.imageshack.us/img31/8585/firstday2of7.jpg
Here's a picture of the nut in the 10mm hole. Looks dodgy (and is!) but seems to be working OK.
http://img594.imageshack.us/img594/8766/firstday4of7.jpg
One of the 75mm brass hinges. They didn't seem to have any play at Bunnings, but once they were mounted to the plywood, a very small amount of play was evident. I don't think it's going to be enough to bother swapping hinges at this point.
http://img709.imageshack.us/img709/6793/firstday7of7.jpg
My crappy tripod head. Has only 1 x female M6 nut in the base, which turns me off a bit. 3 would be ideal for stability (i.e. the tripod head could potentially rotate with the weight of a camera body/lens at certain angles).
http://img684.imageshack.us/img684/9234/firstday6of7.jpg
M6 threaded rod through a ball.. The idea was to mount the ball inside some plumbing tube, a "cap" would then press down on the ball, locking it into desired position. I have yet to find the plumbing. I got this idea from here (http://www.jlc.net/%7Eforce5/Astro/ATM/Barndoor/barndoor.html).
What I do NOT understand (from this (http://www.astunit.com/tonkinsastro/atm/projects/scotch.htm#Improving) guide) is the length of "b". How exactly can this can be a fixed length? As the threaded rod moves the drive board up and down, "b" inevitably changes as this happens. I thought about this for about an hour, then it got dark and had to pack it up for the day. Probably something simple - Or perhaps I'm over-thinking it.
P.S.: I wonder if I could use a solar panel with a capacitor bank or something to power the stepper circuit... Hrmm... might be a bit of a pain though, as I'd have to leave it outside during the daytime to recharge. I do have some 3S li-pos around too that I'm not using.
P.S.S.: Something like this (http://www.dealextreme.com/details.dx/sku.6378) might be suitable as a cheap finder scope. Then again maybe a reflex sight would be better in the dark. There's quite a few other choices on there too.
http://img412.imageshack.us/img412/3667/firstday1of7.jpg
I used 2 x nuts and 2 x washers along with some heatshrink to "lock" the rod's position to the base hinge.
http://img31.imageshack.us/img31/8585/firstday2of7.jpg
Here's a picture of the nut in the 10mm hole. Looks dodgy (and is!) but seems to be working OK.
http://img594.imageshack.us/img594/8766/firstday4of7.jpg
One of the 75mm brass hinges. They didn't seem to have any play at Bunnings, but once they were mounted to the plywood, a very small amount of play was evident. I don't think it's going to be enough to bother swapping hinges at this point.
http://img709.imageshack.us/img709/6793/firstday7of7.jpg
My crappy tripod head. Has only 1 x female M6 nut in the base, which turns me off a bit. 3 would be ideal for stability (i.e. the tripod head could potentially rotate with the weight of a camera body/lens at certain angles).
http://img684.imageshack.us/img684/9234/firstday6of7.jpg
M6 threaded rod through a ball.. The idea was to mount the ball inside some plumbing tube, a "cap" would then press down on the ball, locking it into desired position. I have yet to find the plumbing. I got this idea from here (http://www.jlc.net/%7Eforce5/Astro/ATM/Barndoor/barndoor.html).
What I do NOT understand (from this (http://www.astunit.com/tonkinsastro/atm/projects/scotch.htm#Improving) guide) is the length of "b". How exactly can this can be a fixed length? As the threaded rod moves the drive board up and down, "b" inevitably changes as this happens. I thought about this for about an hour, then it got dark and had to pack it up for the day. Probably something simple - Or perhaps I'm over-thinking it.
P.S.: I wonder if I could use a solar panel with a capacitor bank or something to power the stepper circuit... Hrmm... might be a bit of a pain though, as I'd have to leave it outside during the daytime to recharge. I do have some 3S li-pos around too that I'm not using.
P.S.S.: Something like this (http://www.dealextreme.com/details.dx/sku.6378) might be suitable as a cheap finder scope. Then again maybe a reflex sight would be better in the dark. There's quite a few other choices on there too.