SO after owning a BLF GT70, a GT Mini, and reading all the awesome builds on this site I decided to take the plunge and try to make my own “thrower.”
To make things simple I’ll only use stuff readily available. Parts include:
4”–3” PVC reducer coupling
3” PVC repair coupling
3” PVC end cap
3” PVC pipe
Pushbutton switch (currently only a momentary switch as it’s what I had on hand)
Buck driver (from MicroCenter)
1-Cell 5V 1A USB power bank
Round door knob
1/4”–20 x 2” thumb screw; washers
What I had to source were:
3-1/4” Aluminum heatsink
Fresnel lens (hence the name)
Osram “Flat White 1mm^2” LED on copper MCPCB
Goal:
To eventually make Enderman’s list! (Anywhere is fine for now…)
Construction was straight-forward, using lengths of 3” PVC pipe to connect the fittings. To recess the Fresnel lens into the reducer coupling I used a rabbet bit on a handheld router. I then lined the interior with black felt.
The White Flat LED was secured onto an eBay purchased heatsink with the supplied screws and thermal compound.
To make the RLT dome, I cut a round door knob in half, then cut the aperture to my best guesstimation, and polished the interior. Works decently though it’s not a perfect focus, as the shape is not 100% precisely hemispherical.
The power bank was popped open so that leads could be run to the various components.
I just used this buck driver because I had it, and didn’t want to run the LED at a full 5V because it’s only passively cooled right now I didn’t measure the current but suspect having more will give me a bit more light output.
Two holes were cut (by hand), one for the momentary switch, and one for the end of the power bank. The nice thing about this is that I can charge it in the car, AND use it still as a power bank!
I do have a lux meter but have not familiarized myself yet of it’s operation or how to calculate candela.
EDIT: Some trouble posting pics, so I’ll link my album here…