I would suggest a redesign of the mounting block attachment. Relying on only epoxy to hold several thousand dollars worth of DSLR and lense isn't a good plan.
Bending the threaded rod is best done using a form rather than bending in segments around some fixed corner. A form will be needed and can be made from 1/4" plywood with a circular arc cut along one edge. You will be sandwiching the arc between 2 other pieces of plywood which can be glued, screwed or bolted together. When you bend the rod and release it from the form it will spring back a little which makes the arc slightly larger in diameter from what is desired. Make the arc slightly smaller in diameter to account for the springiness of the rod. When sandwiching the plywood arc between the other pieces of plywood make sure that the outer pieces extends beyond the radius of the arc by several inches, it will form a channel for the rod to guide through while bending around the arc. Near the start the arc drill hole through the two outer pieces of plywood so slipping a screwdriver or bolt through the hole will trap the rod against the arc. Secure the form and proceed with bending the rod around the arc of the form and check the rod's bend against the reference arc desired.
Having worked with epoxy for decades that wood to metal joint with fail in time. Two simple countersunk woods screws into pre-drilled holes in the wood and your good, forever. Threaded rods, copper, brass tubing etc. should all be shape formed around a hard template. It would be nice to fancy it up a tad with some indexing wheels. Neat project.
Great! There's also the type 4 / double hinge version that functions without bending the rod. Also check out the kitchen-timer barn-door that does not require a power source :-)
Cheap materials and cheap discrete parts...Awesome. This is how the people at Make should design their projects. Afordable so that more viewers can built it themselves.
Thats awesome! I wouldn't have bent the threaded rod though. I would have kept it straight. Instead I would have allowed the motor and the captive nut to rotate on two pivots at both ends as the hinge opens.
Great build. Hey, just going to say this out loud... I like your sense of humor at the beginning of the video. Not all posts are winners with people. I think this was a clever way to voice that. Thanks.
Great build. Time lapse photography that goes with the sun in the Northern hemisphere is one potential use. You may not need the arc mechanism for that use. Best Regards for a great post.
The imperfectly bent rod may not itself be as big a problem as the inconsistent resistance it introduces. Since you want the hinge to open at a very specific and consistent angular velocity, perhaps you could use a micro controller like an arduino and an accelerometer (tracking the angle) to adjust the power going to the motor.
You can use straight threaded rod if you split the lower half of the hinge and hinge it in turn. The new hinge would be between the tripod mount and the gears and motor. The gears and motor would move automatically to properly receive the threaded rod (you might want to put an additional receiving nut on the larger gear, at the other end of the shaft).
I hope someone here can confirm my understanding of the concept. With a 10-32 threaded rod and a 1 RPM motor, the rod advances 1/32" every minute. So in one hour, it advances almost 2" (1-7/8", actually). Allowed to continue running, in six hours, it would advance almost 12" and the hinge would be open about 90 degrees (1/4 of a sidereal day, or 1/4 of a full circle). Is that true or are there other factors at play when tracking for that long?
This is awesome... I just wish I understood how to align it accurately here in the Southern Hemisphere. We don't have an equivalent bright Polaris-like star to use... I feel if i went to the effort to build it (and I want to), I wouldn't be able to use it... I'm also a bit confused but that may be because I'm new to this. If I'm not mistaken, unless the centre of the camera's lens is aimed directly down the line of the hinge pin itself, won't that make accuracy decrease dramatically the closer you aim your shots to the celestial pole... because the further away from the hinge the lens is, the more the camera is travelling in circles rather than rotating about a line through itself. Am I misunderstanding something? Probably...
if you have an astronomy app on your phone you could put a phone mount on it and then calibrate it to the south pole point and then switch out for your camera. this would be good for the north pole too since polaris isn't exactly "true north"
What are the values of the resistor and 2 capacitors... also the part numbers for the gears dont pull up the part on the spsi website so a full description of the gears would be appreciated.
Would this still work without bending the rod, if you're only looking to track 5-10 minutes? Tangent error should not be significant in this window. Would you have any tips for a simple redesign that doesn't require drilling and tapping metal?
+Bob Snyder I think it has just some comfortable sense. You(r hand) have more space for settings. And maybe if you do it properly the weight point of the "device" will be top of the stand what you use for more stability. I'm not really sure about this. Just guessing.
Yes. This is why most mounts that you buy outright have a variable speed on them. At half speed, this mount is best used for wide angle shots that attempt to keep both foreground and stars in focus. Long single exposures will begin to blur, but if your horizon subject is far enough away the half speed will keep it relatively in focus while maintaining focus on the stars too
why bend a rod when the hinge's motion if already predefined by the hinge itself. Just use a straight threaded rod to push on the tip of the hinge? or am I missing something here?
+elevengiant Applied directly, this build is very specialized to doing this one task - matchinghte camera movement with the rotation of the earth. You could use the drive system and circuit with a straight threaded rod to drive a motion control system for time lapse dolly slider, though.
+elevengiant What Hung Sewell said...Those fancy time lapse panoramic shots you see all the time nowadays? because of this gadget...don't even bother looking up how much one costs from a photography shop, not pretty.
why not use a retract from an RC aircraft? all the stop downs and everything is built in. Just need your regulator to set the precision speed after you hack out the servo control board or is you have a 4k or 8k resolution retract you could just use an arduino and skip the potentiometer regulator
I would suggest a redesign of the mounting block attachment. Relying on only epoxy to hold several thousand dollars worth of DSLR and lense isn't a good plan.
I second this. Some screws should to the trick.
+Pete Raine Drill two more holes in the metal part and insert two wood screws to fasten the block of wood...
Bending the threaded rod is best done using a form rather than bending in segments around some fixed corner.
A form will be needed and can be made from 1/4" plywood with a circular arc cut along one edge. You will be sandwiching the arc between 2 other pieces of plywood which can be glued, screwed or bolted together.
When you bend the rod and release it from the form it will spring back a little which makes the arc slightly larger in diameter from what is desired. Make the arc slightly smaller in diameter to account for the springiness of the rod.
When sandwiching the plywood arc between the other pieces of plywood make sure that the outer pieces extends beyond the radius of the arc by several inches, it will form a channel for the rod to guide through while bending around the arc.
Near the start the arc drill hole through the two outer pieces of plywood so slipping a screwdriver or bolt through the hole will trap the rod against the arc.
Secure the form and proceed with bending the rod around the arc of the form and check the rod's bend against the reference arc desired.
Awesome, thanks I might try this week that there's no moon and I have some 1/4 scrap wood rolling around.
Having worked with epoxy for decades that wood to metal joint with fail in time. Two simple countersunk woods screws into pre-drilled holes in the wood and your good, forever. Threaded rods, copper, brass tubing etc. should all be shape formed around a hard template. It would be nice to fancy it up a tad with some indexing wheels. Neat project.
+66tbird1 thanks, this is a useful comment. Keep on trucking !
Great! There's also the type 4 / double hinge version that functions without bending the rod. Also check out the kitchen-timer barn-door that does not require a power source :-)
Cheap materials and cheap discrete parts...Awesome. This is how the people at Make should design their projects. Afordable so that more viewers can built it themselves.
Thats awesome! I wouldn't have bent the threaded rod though. I would have kept it straight. Instead I would have allowed the motor and the captive nut to rotate on two pivots at both ends as the hinge opens.
thats a great project, the simplicity of it make it so great,
Very impressive! Thanks for sharing!
Nice project indeed, easy enough to do.
Keep on trucking, folks !
Great build. Hey, just going to say this out loud... I like your sense of humor at the beginning of the video. Not all posts are winners with people. I think this was a clever way to voice that. Thanks.
*Love* the first 5secs!!
Great build.
Time lapse photography that goes with the sun in the Northern hemisphere is one potential use.
You may not need the arc mechanism for that use.
Best Regards for a great post.
The imperfectly bent rod may not itself be as big a problem as the inconsistent resistance it introduces. Since you want the hinge to open at a very specific and consistent angular velocity, perhaps you could use a micro controller like an arduino and an accelerometer (tracking the angle) to adjust the power going to the motor.
Cool!
You can use straight threaded rod if you split the lower half of the hinge and hinge it in turn. The new hinge would be between the tripod mount and the gears and motor. The gears and motor would move automatically to properly receive the threaded rod (you might want to put an additional receiving nut on the larger gear, at the other end of the shaft).
***** It's a flat hinge. The movement can't be circular. And if your hinges are clean there's nothing stopping the movement from being smooth.
I love you guys.
A brass threaded rod is easier to bend than steel. Bend 2 or 3 feet of rod and cut out the best 5 inches for the tracker.
Wouldn't it be easier to hinge the drive motor so it can turn a little bit, enabling use of a straight threaded rod instead of a bent one?
a heliostat with a parabolic reflector is worthy of consideration. just a variation of this tracker.
I hope someone here can confirm my understanding of the concept. With a 10-32 threaded rod and a 1 RPM motor, the rod advances 1/32" every minute. So in one hour, it advances almost 2" (1-7/8", actually). Allowed to continue running, in six hours, it would advance almost 12" and the hinge would be open about 90 degrees (1/4 of a sidereal day, or 1/4 of a full circle). Is that true or are there other factors at play when tracking for that long?
Awesome :) Thumbs up :D
Alex
Maybe have a straight threaded rod push up on the hinge
This is awesome... I just wish I understood how to align it accurately here in the Southern Hemisphere. We don't have an equivalent bright Polaris-like star to use... I feel if i went to the effort to build it (and I want to), I wouldn't be able to use it... I'm also a bit confused but that may be because I'm new to this. If I'm not mistaken, unless the centre of the camera's lens is aimed directly down the line of the hinge pin itself, won't that make accuracy decrease dramatically the closer you aim your shots to the celestial pole... because the further away from the hinge the lens is, the more the camera is travelling in circles rather than rotating about a line through itself. Am I misunderstanding something? Probably...
if you have an astronomy app on your phone you could put a phone mount on it and then calibrate it to the south pole point and then switch out for your camera. this would be good for the north pole too since polaris isn't exactly "true north"
What are the values of the resistor and 2 capacitors... also the part numbers for the gears dont pull up the part on the spsi website so a full description of the gears would be appreciated.
Can we get a 3d printed version?
Would this still work without bending the rod, if you're only looking to track 5-10 minutes? Tangent error should not be significant in this window. Would you have any tips for a simple redesign that doesn't require drilling and tapping metal?
You can also use starstax software for star trail photography (curved star lines)
what camera did you use to get them stars? model and lens specs plz :)
What is the point of the piece of wood? Why not just bolt the gimbal directly to the hinge?
+Bob Snyder I think it has just some comfortable sense. You(r hand) have more space for settings. And maybe if you do it properly the weight point of the "device" will be top of the stand what you use for more stability.
I'm not really sure about this. Just guessing.
Won't the objects in the foreground get blurred?
Yes. This is why most mounts that you buy outright have a variable speed on them. At half speed, this mount is best used for wide angle shots that attempt to keep both foreground and stars in focus. Long single exposures will begin to blur, but if your horizon subject is far enough away the half speed will keep it relatively in focus while maintaining focus on the stars too
Almost 1 million what r u guys going to do for that
Why in the world is the motor used in this project $30?
why bend a rod when the hinge's motion if already predefined by the hinge itself.
Just use a straight threaded rod to push on the tip of the hinge? or am I missing something here?
so that the rod pushes it at a consistant speed. without the bend you would have to adjust the speed for the change in pushing angle.
What other applications can there be? It is amazing but im not into these.
+elevengiant Applied directly, this build is very specialized to doing this one task - matchinghte camera movement with the rotation of the earth. You could use the drive system and circuit with a straight threaded rod to drive a motion control system for time lapse dolly slider, though.
+elevengiant sun tracking a solar cooker comes to mind. But that is about it. Good question.
+elevengiant With some modifications you could make a camera slider for some time lapse photography.
+elevengiant What Hung Sewell said...Those fancy time lapse panoramic shots you see all the time nowadays? because of this gadget...don't even bother looking up how much one costs from a photography shop, not pretty.
counterclockwise rotation engine ????
woooow
This plan uses a corrective cam instead of a curved rod. See step 5. www.instructables.com/id/Build-a-Motorized-Barn-Door-Tracker/?ALLSTEPS
What dimanand
why not use a retract from an RC aircraft? all the stop downs and everything is built in. Just need your regulator to set the precision speed after you hack out the servo control board or is you have a 4k or 8k resolution retract you could just use an arduino and skip the potentiometer regulator
+christopher campi Your idea costs more. They done it so that anyone can afford to build it.
needed a stronger kick on that Rpi project in the beginning -1
...jk...
first!!
If you could tell me where I could see photos of the wiring I’d really appreciate it. I’m not good with real schematics...