grins projector, recoil and test light builds

Thanks
I have been working on getting meter readings right so I can do some comparisons with collars. I have the same size round nose router bit as the genuine collar. So I will make one from aluminium and polish it. I will also make one from brass then tin it with pure silver. The tests so far prove I can get it to focus as good as the genuine one. Have a hunch the silver coating will be as good as you will get for home built.

Ohhh yesssss! DIY collar!!

Sssh can be a little controversial. Research suggests silver may be as good as as as … I can make. Cutting it by hand is very accurate if i can find the appropriate diamond cutter I will try glass.

likevvii,
How is the LEP going? I would like to build 900mm LEP recoil.

It is going really really good.
I will soon be making some post about it.

Almost all of the critical components have arrived.

I think i’ve put like 60+ hours on it so far?

Likevvii I cant wait to see it.
I have the platform to build a monster hopefully a LEP recoil. It has been sitting in the paddock for at least 20yrs. I started it about 10yr ago so it should run just need to give it a service, flush the fuel tank and bleed the fuel lines. I have the diff but It will need an alternator mounted on it so maybe an electric motor and the diesel engine will be a battery charger.

Grin, you don’t do things by half do you lol!? :stuck_out_tongue: so interesting.

Cheers GOOSE, sometimes I get half way through something and then realise it wont work or could be done a better way :smiley: I found the 900mm mirror when I did a random ebay search and couldnt resist buying it, it was cheap for what it is and a great addition to my collection of parts and lights.
It has been a steep learning curve and this thread made me realise how little I actually know so I have gone back over things and reassessed what I am doing. Now I have a better understanding of why I decided to build the lens lights like I did. They are based on elipsodial reflector spot lights, telescopes and camera lenses.
A bit of an update I have been sorting things out the last week or 2 and havent done much on the lights. Im also wait for parts from china and that could be a while.
One of the things i did get was a 68mm parabolic mirror from aliexpress with the aim of building a smallish recoil.

The focal point appears to be down in the mirror which makes it hard to use it for what I brought it for. but when I turn it upside down on an LED I get this result.

It looks promising for a shuttering collar to keep light of the internal lens barrel :wink: I think a bigger one of these will cut the aperture i just need to do some calculations to work out aperture size. Then destroy one to see if it works.






Damn that’s a tight spot, what lens is that??

Looks like a regular spherical lens, not aspheric, because of the spill around the square die projection

Australia NSW News—Police in Hunter Valley were called by numerous alarmed citizens who reported UFOs flying in the local sky. Investigation details were not available.

Just 2 x 145mm fl370mm aliexpress lens. I find a single lens doesnt work as well as 2. It did attract attention last night because of the projection onto the clouds

Ah yeah, I think I remember something about multiple spherical lenses vs single aspherical lens having a similar effect on collimation.
That’s prett cool.

I have done a lot of reading and looking to find more information on what im doing and they are pretty much elipsodial reflector spot light without the reflector. There is a thread way way back here
Some lights use a double convex lens this could explain the lens configuration in the W30. It will be interesting to see what these W50 lens is.

Well um I scored these today are they a matching pair?





And a bonus

Couldnt believe it.

Nice.
They def need a recoating though…

At a guess the damage may have come from an exploding globe. Looks like it has had molten glass sprayed on them. Monday I will inquire about getting them resilvered there is a place that restores antique mirrors. I will see if the bloke who gave them to me and probably get a few of his restored aswell.

Do you know how these were used—was it related to flash photography or stage lights? Curious flat section, what’s that about?

Type # 12 - 4¼ - 25

Here’s my guesses:

12” diameter
4¼ depth or sag of the lens
25 focal length or radius of curvature

Im not exactly sure but I think you are close. By the markings and being of high quality I wouldmthink military lights of some sort. The bloke who gave them to me brought them from a bloke on stalkbook who just found them in the back of his shed.
There was another two like them and they were aluminium. Thats why I think maybe they were in the same light. For temporary landing lights or something. The date on most of them was 1940s but it is very hard to find information on them. Only problem is the more you look the more bargains you find.
This is one that I sold. Looks like a ceramic backing


This is the 250mm I kept and hopefully to be restored






Modified W30 next to a maxabeam.