T Hinge motorised all metal Barn Door tracker and Stand

[adder001]

Hi folks,

Finally finished my all metal Barn door tracker. It consists of 2 x 12" T hinges from Wilkos cost about £1 each, a 1rpm motor £6 banggood.com, 2 x 40 teeth spur gears £1.10 at cpc.co.uk and a length of M6 rod £2 cpc.co.uk which I curved to a radious of 9 inches  and various L brackets washers, bolts etc.

Then I had to make a circuit to control the voltage to the motor. This was an LM317 chip a couple of capacitors and an adjustable resistor 10K. I enclosed it all in a plastic box and included a switch, an Led and a battery holder.

As an extra I used up some copper pipe that I had lying aound and made myself a tripod(well a quadpod really as it has 4 legs) with a small altitude adjuster screw on it.

So far all tests look good I can get the motor rotating at 1 RPM which is what is required for a M6 thread at 9" radius. It can be adjusted faster or slower to compensate for temperature and battery state.

I have marked both motors so I can time the seconds between each revolution.

I hope this is of some help to anyone who wishes to make similar.

 

[Peter Drew]

Very resourceful use of components. Looks like a lunar lander.  

[Mick J]

Brilliant, I love the way all the bolts are too long 

[adder001]

1 hour ago, Mick J said:

Brilliant, I love the way all the bolts are too long 

Thanks, I f it all works well I will probably tidy everything up and maybe even paint it. Just need some good weather and time away from normal work/life/kids etc., to test it

[adder001]

2 hours ago, Peter Drew said:

Very resourceful use of components. Looks like a lunar lander.  

Yeah its amazing what can be made out of bits probably most people(or geeky gadget/diy'ers like me) have lying around in their sheds/workshops. I suppose if this had to be made from complete scratch, ie. buying everything from new it would probably cost around £20 (without the tripod).

The time and work involved is the main part due to drilling and cutting holes in brackets, bending rods and soldering circuits together etc.

Most of the calculations have been done before and I got most of my ideas from Gary Seronick's website here http://garyseronik.com/a-tracking-platform-for-astrophotography/#more-52

which has loads of information such as formulas and calculations.

I just needed to modify it to suit my components as it is American it uses the imperial system where I only had metric. Actually an M6 thread turns out to be more accurate due to the threads per inch.

So all in all its great what can be done and the amount of information that amateur astronomers pass on to each other freely is fantastic

[happy-kat]

That's fab, looking forward to first test.

I found a great site where you enter thread pitch etc. and it gave the distance needed to the hinge as I already had a bolt though you are all done now.

[adder001]

Ok so just done a quick test. I have been itching to try it. So I had about 10 minutes due to the clouds keep coming and going so I really rushed this. I spent quite a bit of time polar aligning the hinge but where I would normally spend quite a lot of time getting the focus right I didn't bother this time as I was only interested in how well it tracked.

So here are two pics, both 1 minute at 75mm (I used a Canon EF-II 75-300 lens) 800 ISO. One with the tacking motor on and the other with it switched off to show the difference.

I am quite chuffed with the results. I have a few modifications that I need to make though. The camera mount is not strong enough, it keeps trying to move and I had to really nip the bolts up tight to prevent this so that is not ideal when changing targets as it starts to make my fingers hurt and I need to make the tripod easier to adjust by modifying the bracket.

Also it is quite wobbly  due to the thinness of the hinges themselves so I may try and reinforce the base of the bottom hinge somehow. It isn't a big problem though, it just means that when you make any adjustments you just have to wait a couple of seconds to let the wobbling about stop before taking any pictures.

So all in all not bad results

 

[happy-kat]

Great first test. I use this ball head find it very good and takes 8 kilos (I got this one after starting with a different smaller one and camera adjustment was hard difficult). It is full size thread so I got a bag of camera tripod thread reducers to use.

link

 

[adder001]

Thanks for the link Happy-Kat that looks pretty goo, quite cheap too, I think that will be the route that I go down with this, so It should be ok to hold a dslr with a 300m lens on it then if it holds 8 kilos thats quite a weight.

cheers

[adder001]

meant pretty good, not pretty goo .. DOH!!

[happy-kat]

I've found I'm still using the original release plate on my camera but some reviews has problem with there's with the little tightening bolt head snapping. The ball head itself is I've found very strong and smooth to use, someone on this site puts a small refractor on their's with a pan plate.

[billyharris72]

That's a good result - nice round stars with a decent exposure length. Would be interesting to see how long you can get at say 200mm - I suspect it would be fine for at least 30 seconds, and hopefully a bit more. Quite fancy one of these myself as a portable option.

Billy.