Large Nipcow Disk idea?

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Large Nipcow Disk idea?

Postby MarbleMad » Tue Jun 06, 2023 3:49 am

So I want to make a large nipcow disk. Tell me whether you think this approach is a good idea or a disaster waiting to happen.
Laser cut, 500mm wide 3mm acrylic disk with large 1cm holes but apply vinyl stickers with pin holes in them so you have a super thin disk.
Viable or madness? What do you think?

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Re: Large Nipcow Disk idea?

Postby Klaas Robers » Tue Jun 06, 2023 7:11 pm

The size is not a problem, and is also not unusual. The Baird Televisor had a disc of half a meter in diameter. But the thickness...... That makes the disc quite heavy and then rotating at 12½ rev/sec. ....... Make at least a strong metal screen around it.

Good luck, you may need it.
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Re: Large Nipcow Disk idea?

Postby MarbleMad » Wed Jun 07, 2023 12:30 am

ok, I hear you. So are there any good modern alternative materials that could be laser cut?
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Re: Large Nipcow Disk idea?

Postby MarbleMad » Thu Jun 08, 2023 7:20 am

What about using a similar approach but instead of 3mm acrylic, I used corrigated plastic? like Correx?. I like the cardboard idea but i'm sure it would deteriorate very quickly in my workshop located in an uninsulated industrial building.
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Re: Large Nipcow Disk idea?

Postby Klaas Robers » Thu Jun 08, 2023 11:51 pm

I don't know what it is. Point is that the disc should not be too heavy. The original 50 cm large BAIRD discs were made of thin aluminium and the square holes were punched, with good precision.

Any way, applying the small hole stickers with enough position precision for a Nipkow disc, will be difficult for you. Think of a precision of 0.05 mm = 50 micron. Everybody trying to make a Nipkow disc will encounter that problem.
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Re: Large Nipcow Disk idea?

Postby MarbleMad » Fri Jun 09, 2023 10:51 pm

Yes the precision is going to be a problem. My thinking was, with stickers, if i saw one of the lines was messed up, the sticker could be removed and replaced.
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Re: Large Nipcow Disk idea?

Postby Harry Dalek » Sat Jun 10, 2023 12:17 am

MarbleMad wrote:Yes the precision is going to be a problem. My thinking was, with stickers, if i saw one of the lines was messed up, the sticker could be removed and replaced.


Andrew i think from memory used the idea years ago .
Do experiment you will have to work out a test as the hole sticker will need to slide a bit better to fix glue after .
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Re: Large Nipcow Disk idea?

Postby Klaas Robers » Mon Jun 12, 2023 1:30 am

I have no idea about the precision of your laser cut machine. Can you make square holes of 1 mm x 1 mm? And what is the step size of the laser cutter? Can you make steps of 0.05 mm? if yes, then I would prefer making the holes by the laser cutter. Any way you will spray the disc opaque black, so you get any way a thin disc. Can you laser cut in a transparent acylic disc? May be that is opaque for IR laser wave lengthts?
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Re: Large Nipcow Disk idea?

Postby MarbleMad » Mon Aug 28, 2023 7:11 am

So I built a 40 then a 50cm disk. pretty pleased with the results. it's far from perfect but it's good enough for now.
I used black corrigated plastic with large holes which I then covered in tape and made pin holes in.
At first I used PVC tape but the holes would change shape and slowly close up so I switched to aluminium tape. I found stuff used for theater lighting that had a black finish.
You can make a pin hole in that and it will keep its shape.
the disk is spinned up with a large stepper motor which is noisy as hell and took a bit of custom video encoding to synch but for me it was a lot easier than trying to get analogue electronics pushing a DC motor.
I'm pretty pleased with the results and am now planning an art exhibit incorporating the mechanism.
I need a collection of short movies though. 3 - 4 minutes.
I quite like the idea of putting something contemporary in the thing. Does anyone know of any dieo artists, animators or film makers who make low definition video?
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Re: Large Nipcow Disk idea?

Postby Harry Dalek » Mon Aug 28, 2023 7:03 pm

MarbleMad wrote:So I built a 40 then a 50cm disk. pretty pleased with the results. it's far from perfect but it's good enough for now.
I used black corrigated plastic with large holes which I then covered in tape and made pin holes in.
At first I used PVC tape but the holes would change shape and slowly close up so I switched to aluminium tape. I found stuff used for theater lighting that had a black finish.
You can make a pin hole in that and it will keep its shape.
the disk is spinned up with a large stepper motor which is noisy as hell and took a bit of custom video encoding to synch but for me it was a lot easier than trying to get analogue electronics pushing a DC motor.
I'm pretty pleased with the results and am now planning an art exhibit incorporating the mechanism.
I need a collection of short movies though. 3 - 4 minutes.
I quite like the idea of putting something contemporary in the thing. Does anyone know of any dieo artists, animators or film makers who make low definition video?


Look in software here and sound menus you can either make your own or use some that have been uploaded by others. With Gary's software you can make NBTV movies from movie videos or stills in different NBTV standards you would want 32 line more than likely . Explore and you will find ! if not ask more questions !
The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
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Re: Large Nipcow Disk idea?

Postby MarbleMad » Wed Aug 30, 2023 9:09 am

Thanks but that's all done. Wrote my own software in processing and the hardware is working. it may not be super perfect but it makes the point.
Just have to fix some sound issues and build the case now ... oh and find some content:
https://www.youtube.com/watch?v=cty709o5chs
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