grins projector, recoil and test light builds

Awesome cliffs, pity they are too soft for climbing I have been looking at them for 40 years and you notice they well I notice how they have changed. That is on the edge of the wollemi and golburn river national parks.

well I just sat the mirror up on a chair and taped a spider of a smaller recoil to the tripod and stood it in front of it. Led is SBT-90 @ 12amp




W30


K75


Wowwwww

The first beamshot looks so interesting.

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OK , I understand better now. :beer:
So your build will be adjustable focus between the LED and your first plano-convex lens and also the big adjustment between those two together and the big plano-convex lens to create a Zoomie. I do see your collimator covering the LED also. :wink:
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After you get it finished, may we get some dimensions from you for reference ? Nothing is better than working numbers ! :smiley:
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There has been much discussion on this subject over the years but very little experimentation that you are doing ” grin “. :+1:
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Keep up the good work and blaze the trail, we will follow you :beer:
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Breaking News: UFOs across Australian Skies sending energy beams to Earth

I should not have drawn the 2 lens that light will only have a single 150mm diameter lens with 177mm back focal length. I do have another lens combo for it but i will eventually build a light for them. I would like to have both lenses adjustable in my two element lenses. So for this light it will be 1 to make it simpler.
A couple of things have me puzzled one how to stop the piston spinning with the motor. Dowel or keyway im not sure. The other is how do I stop the led power cables getting caught.
Anyone can use my ideas I post here if they be crazy enough. :smiley:

[quote=grin]
well I just sat the mirror up on a chair and taped a spider of a smaller recoil to the tripod and stood it in front of it. Led is SBT-90 @ 12amp




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WOW ! that is :smiling_imp:
Looks like a comet :heart_eyes:
Thank You for sharing with pictures :beer:
Be careful ! don’t let it get too hot !
I wonder how you could check the throw on it ? You would need to get a 800 meters away to check it !!!
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I can only run it for short periods of time so normally turn it on take the photo turn it off. I will do something about cooling very soon.


This was taken within the beam
The other thing it is a full moon tonight and you have all the ambient light from the town.

When the beam looks like that it is over focused of to far away when the led is too close it looks like a big fat column

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How to stop it from spinning…….( EDITED )
You will need a keyway to keep it smooth, preferably with the ( .187 square key ) key pressed into the full length copper heatsink if possible. Copper is sticky and a key sliding in the copper may hangup more than a key sliding in the bushing in the housing. Also, if you have room to make the bushing close in length ( OR LONGER ) to the diameter of the busing will help eliminate excessive wobble as it moves. A tight slip fit of .0005 or less should be good, start with a tight fit and a coat of high viscosity oil or thin coat of grease to keep it from locking up. If you make the bushing from Nylon or some other dense plastic you may not need oil or grease or worry about dirt or dust getting on the copper and binding or jamming it up. Oil attracts dirt.
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If you do go the other way and slot the full length of the copper heat sink, use a brass or hard plastic key in the bushing to stop sticking. I would use something non metal for the bushing so it does not jam or need oil. :wink:
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I love this thread.

Only on BLF would a member drive 4 hours one way to get a ridiculously large mirror to build an ET spotter :slight_smile:

Man I love this Place!

Thanks for all the updates and all you do.
By the way,
You Won!

Thanks for the good words. I did win 8^)the MF01s is a nice light. I have been thinking about 8th annual comp. Maybe a right angle recoil.
here are the last few of the night





Any plans to get lux measurements so you can know your throw in cd? I am very curious to know the throw of that giant mirror.

May I have some information of your parabolic mirror? Glass, metal, thickness. I will definitely buy something similar in the future.

With an off-axis parabolic mirror?
I considered making one before, never ended up doing it because It was cheaper to just buy a regular parabolic mirror of a larger size and get more throw.,
It’s a cool idea though, never been done before.

Me experimenting with a few options from various brands, making sure they are fully covered with light when using a collar.

Focal length looks to be 400mm but being imperial I would say the focal length is 16 inchs










Crazy :smiley: :+1:

:smiley:

That’s a great find on the mirror and being able to put it to good use.

1940
C.A.Parsons &Co Ltd

90/408 =? 90 cm diameter and 408mm focal

OB 11624 =? serial number

from wiki pedi
The Company was founded by Charles Algernon Parsons in 1889 to produce steam turbines, his own invention. At the beginning of the 20th century, the company was producing up to 50 turbines a year at its factory in Heaton in Newcastle upon Tyne.

C. A. Parsons and Company was a British engineering firm which was once one of the largest employers on Tyneside. The company became Reyrolle Parsons in 1968, merged with Clarke Chapman to form Northern Engineering Industries in 1977, became part of Rolls-Royce plc in 1989, and still survives today as a division of Siemens.

He also designed special Optics for searchlights:
http://houseofdavid.ca/parsons.htm#searchlight

Some of those photo’s look like some sort of Alien arrival lol! mad……