The Shark Screw

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The Shark Screw

Postby Harry Dalek » Fri Oct 23, 2020 9:09 pm

A tiny Mirror screw ? well my Blades turned up and so far i have stacked 64 blades ....i am going to need glasses for this one !
The idea some time ago is to make a Mirror screw one way or another without drilling and here i got some cheap razer Blades and plan to polish them up and adjust each blades angle i am not sure how this one will go and i have never tried this before .
I suppose i have a few steps to work out ....i started off to mount them some way bolting them and using a old HD seems good idea so far but i have the problem how to use the idea and easy remove to adjust the blades ............so this is idea one so far .
Its funny was not expecting the stacked blade edges to look dark and not at all sharp all stacked together unlike their deadly sharp edge individually ! only one slight cut on the finger so far :(
i will be doing a lot of reading on others mirror screws here on the forum ..not getting the angles even i would think the result would be a wavy video harder when its small..
This is mainly a first try before i try a bigger version least no drilling needed here on this first experimental one .
Attachments
P1070272.JPG
P1070270.JPG
Shark-SS.jpg
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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Harry Dalek
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Re: The Shark Screw

Postby Harry Dalek » Mon Oct 26, 2020 7:21 pm

Still thinking about the mounting part main problem i have bearings but wrong size for the bolt so not going much further till thats worked out .
BTW this is a great way to make some thing to hold your bearings

youtu.be/SGYZGCYIgXQ
Below clipping i am not sure if he is adjusting the screw or dusting or painting non reflecting area no idea but did give me the idea i need a tool to move the blades only thing i can think of is either a pin or another blade to move each
Wireless-World-1931-04-OCR-Page-0013.pdf_-_2020-10-24_12.31.07.png

The front and end plates on some Screws are really needed for a thinner metal plates to keep them from spreading at the edges .
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The 180 line screw below is interesting as the light must be in the case i would say in the pillar to the left directed at the screw out of view to us guessing .
Wireless-World-1934-09-.png
Wireless-World-1934-09-.png (182.33 KiB) Viewed 246 times
Attachments
Television-1934MS.jpg
Television-1934MS.jpg (174.7 KiB) Viewed 246 times
Practical-Television-1957-.png
Practical-Television-1957-.png (237.84 KiB) Viewed 246 times
Screen 00001.jpg
Screen 00001.jpg (56.36 KiB) Viewed 246 times
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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Harry Dalek
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Re: The Shark Screw

Postby Harry Dalek » Fri Oct 30, 2020 3:23 pm

A bit of progress today ... I am happy with the little test bed idea using and old Hard drive case and voice coil bearings and cd player motor ,it had to rotate it true be able to dive the screw and be able to easily as possible adjust the blades tightness against each other .

P1070396.JPG


Only worked it all out today so only one bolt so far holding the old voice coil to the HD housing i have left it for the being for centring ..even so no problems as is at top motor speed

P1070386.JPG


Looking at the the blades them self's they are sharpened to an angle which is roughly 7 to 8 degrees which have the reflective properties wonder if i could use these ,instead of having to view the screw dead on 0 degrees if possible ,i am not sure if they only reflect the whole screw at 0 degrees at 7 or 8 degrees i would think at least the top bracket would be in the way at the length both are ...any case got to adjust the 64 blades and always go back to the original idea .
Attachments
P1070394.JPG
P1070399.JPG
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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Harry Dalek
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Re: The Shark Screw

Postby Viewmaster » Fri Oct 30, 2020 5:33 pm

That's an interesting challenge you have taken on, Harry. When working it would sit nicely next to my
Nipkow Nipper... the World's smallest disc and mirror screw NBTV's. :)

One big problem is your setting the blades angles to each other.
Maybe oil their surfaces so that they slide easier with each other.
A means of locking each blade, when set, is a headache.
“One small step for a man,"......because he has Arthritis.
Albert.
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Re: The Shark Screw

Postby Harry Dalek » Fri Oct 30, 2020 8:42 pm

Viewmaster wrote:That's an interesting challenge you have taken on, Harry. When working it would sit nicely next to my
Nipkow Nipper... the World's smallest disc and mirror screw NBTV's. :)

One big problem is your setting the blades angles to each other.
Maybe oil their surfaces so that they slide easier with each other.
A means of locking each blade, when set, is a headache.


Hi Albert ; )

I Had been thinking about the angles and such Albert effect the resulting image size making a very think screw may be i will have to run it at twice the speed showing 2 images perhaps ,i am not sure what distance of the thin light has to be to the screw if to far or to close zoom effect ? .
Yes it very well could be the nipper of the mirror screws i only recall the 30s French hand held mirror screw being the smallest classic from the time mirror screw...they were really made to make a larger image so that could be the reason for only one smaller screw ,not sure if any one these days has tried it small ,my stainless steel 15cm rulers have turned up but i need a drill press or drill guide to use those for a future larger mirror screw .
This one would be better with more blades for a higher line rate screw but i will be happy if i can make any thing out in this first try .
Yes you are right adjusting the screw will be a big problem i want it so i can adjust the blades and hope they stay in place once i adjust the next ,reason for the top and bottom plates are to hold the blades tight along the length so there will be no movement well stacked as they are now there isn't so i think that will work .

I will take your oil idea on if they don't cooperate .
Attachments
P1070383.JPG
P1070390.JPG
P1070389.JPG
Television-1934-02-S-OCR.pdf_-_2020-10-24_19.52.06.jpg
Television-1934-02-S-OCR.pdf_-_2020-10-24_19.52.06.jpg (133.18 KiB) Viewed 192 times
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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Harry Dalek
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Re: The Shark Screw

Postby Viewmaster » Fri Oct 30, 2020 9:47 pm

If the clamp only covered the centre of the blades you may be able to make a rod of exprerimental diameter/shape
to pass through the slots towards the end of the blades. This would help in alignment and also
stop blades moving relative to each other. You are dealing with thousandths of an inch in
required accuracy blade to blade to get a good picture.
Eventually you could do what I did and set up a tiny camera so one could see the picture larger....
...but in a way, that defeats the object of miniaturization. :)
“One small step for a man,"......because he has Arthritis.
Albert.
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Re: The Shark Screw

Postby Harry Dalek » Sat Oct 31, 2020 7:54 am

Viewmaster wrote:If the clamp only covered the centre of the blades you may be able to make a rod of exprerimental diameter/shape
to pass through the slots towards the end of the blades. This would help in alignment and also
stop blades moving relative to each other. You are dealing with thousandths of an inch in
required accuracy blade to blade to get a good picture.
Eventually you could do what I did and set up a tiny camera so one could see the picture larger....
...but in a way, that defeats the object of miniaturization. :)


Yep another big problem the accuracy as you say ,i would think if they are out to much the image will look wavy .
What i am not to sure about is the amount of difference in the angle to use which i think adjusts the viewing distance ....if its like a satellite dish a deep dish will give a closer focal point and a shallow dish one further away but in my case since this is so tiny i am not sure this matters so much .
Yes a rod adjusting each blade to the next giving same angle result would be a good thing one also good thing about the blades all being 100% the same is holes shapes marking are all in the same place to also use as a guide .
i think a NBTV letter test card would be viewable to the eye making a cd nipkow has been done and image result would be a similar size to this my case glasses used for sure ! but i do have a microscope camera better detail .
Here i am more using the razer blades for what they are made from and because i didn't have to drill accurate holes ! so good for an experimental mirror screw ,down size as we know Tiny and blades very thin for a low definition video .
Below i found a small screw NBTV version some made in the early 2000's gives me an idea of the light distance for some thing this size ....for mine light size would be tiny
Attachments
davidmirscrew (1).jpg
davidmirscrew (1).jpg (38.59 KiB) Viewed 186 times
1935_TV_Today_Part_1-Pg13.gif
1935_TV_Today_Part_1-Pg13.gif (99.88 KiB) Viewed 186 times
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: The Shark Screw

Postby Harry Dalek » Sat Oct 31, 2020 6:16 pm

Going to try and polish the 0 degrees on the blades i was thinking no need to make this harder with angles not knowing its going to work .

I did the best i could today with what i had handy so it reflects better than it did at this angle before which was no reflection at all apart from a grey ..but mirror like finish still a ways off but i will try.
Attachments
PICT1063.JPG
PICT1066.JPG
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.
User avatar
Harry Dalek
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Posts: 4426
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Re: The Shark Screw

Postby Harry Dalek » Sun Nov 01, 2020 3:57 pm

I did a bit more polishing today and giving the screw construction a first go so worst case i just have to do it again, here trying for about 8 degrees since there's a shape of the blade i can use as a template even so its hard to keep them in place so pretty much one at a time steady hand .
P1070429.JPG

P1070428.JPG


Don't really notice or think of things till you give it a go i can see why on larger screw i think it was on Steve O's mirror screw postings each slate is clamped in place looking again it was your idea Albert ..here its a bit small for that the French Brami screw had little handles for adjusting the slats great idea...i was thinking a magnet would help till built but that was a bit useless ....the problem you have thinner the slates are is bowing when you tighten the end plates have to find something like 2 jar lids something round but not sure they are strong enough stop the bowing tighter you push down on the screw .
Need something thicker like the end plates below image
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i did find the first blade had to be taped at the edge down to start it off other wise movement on the next tape was just pulled free after it was built

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So here just tried to place each blade to the template idea the corner of the blade shape steady hand more than likely a bit out here and there which would give a wonky line if shown i suppose .

P1070440.JPG


The top and bottom plates to hold the screw blade's flat no bowing are fine for polishing but i can see they should be round when this is now a screw .
P1070442.JPG


i would be happy to get some thing recognizable out of it find out in time .
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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Harry Dalek
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