Large Wavien Collar = Big Zoomie

I haven’t been very active on this forum for a while but thought my current project might be of interest to the lucky few who managed to acquire Wavien collars while they were available as well as those interested in aspherics and zoomies. I was also fortunate enough to pick up a set thru Amazon just before the last 3 sets were scarfed up by another BLF MEMber.

My project is similar the one built by gaston01 in that it uses a PVC plumbing adapter but being poorer, I’m using a cheap C8 battery tube and a home made aluminum heat sink. The only other out of pocket cost was $10 for an 88mm lens and some screws. I found a 5 foot length of 3 inch copper pipe in the basement and some 0.25 inch aluminum sheet at the shop. The large Wavien collar has a 2.75 inch ID and roughly a 3 inch OD. The copper pipe’s ID measures 3.0625 inch so there’s a little wiggle room. The PVC cuts like butter so turning the IDs to press fit the 88mm lens into the large end and allow a 2 inch lenth of the copper pipe to slide into the smaller end was a piece of cake.

The most critical part is the aluminum plate connecting everything together as I didn’t want to use any epoxy as in other builds. I cut out a 3 inch disk from the 0.25 inch sheet and bored a slightly undersized pocket for a 20.5mm Noctigon in the center. Next, I made a mandrel so that the piece could be flipped without changing it’s exact center. Now, I was able to turn a lip/recess to mate with the Wavien collar’s ID while keepng the pocket on the opposite side perfectly concentric with it. By carefully filing away the high points around the circumference, a 20.5 mm star becomes a light press into the pocket and self centers to the collar. All the guess work for radial focussing is eliminated and only shimming the top of the star for focussing depth might be necessary. This way, any XML2, XPG2 or XPE2, domed or dedomed, can be easily installed and focussed.

All the critical dimensions came out perfect but I blew it right off the bat by assuming my 3 inch copper pipe had a 3 inch ID but it measures 3.0625 inches. Oh well, nothing a little JB Weld can’t fix. Right now, I have it wrapped with multiple layers of scotch tape to fill the gap. No biggie since the 2mm allen heads do all the work of holding it together. Not sure what shape I what to make the PVC but there’s plenty of material there to work with.

Sorry, no beamshots yet. Just wanted to share some pics before I button it up. I still have to add some TIM and solder in the wires. Judging from the EFL and apparent die size, I expect a ~1.4 degree beam with the domed XPG2 S4 I’ll be using. Dedomed should get it under 1 degree but lens quality may be the limiting factor in actual use. I have another (hopefully better) lens coming.








looking good, cant wait for the beam shots.

Wow, that’s some serious lego-ing you have going on there. Please, please, please post numbers with and without the collar. Although I’ve read the threads on how these work, it still doesn’t all quite click. Again, nice work. Can’t wait to see the beamshots. Also, you mentioned shaping the PVC…are you going to turn it?

This is a real nice project
Can’t wait for beamshots

subscribed :)

I tried to get some beam shots but I need to figure out how to set my camera for a longer exposure. It’s just as well because the beam wasn’t clean at all. The lens is crap! The focal length is all over the place. I tried a smaller (77mm) high quality lens that has a slightly shorter but well defined focal length and it was pretty impressive :slight_smile: . I wanted so much for the bigger lens to work because it would’ve thrown a pretty tight beam. At least, I now know what a crappy looks like before I go thru the trouble of mounting it.

I need to cut another piece of copper pipe to mount and fine tune the smaller lens, then I’ll try to get some good beam shots. The beam should be similar to others that use collars but I think it’ll be slightly wider, whiter and brighter because I’m using a higher binned, domed XPG2. Plus, I’m using the large collar which I suspect might give a cleaner edge.

I’m going to ditch the PVC and just stick the 77mm lens right into the copper pipe. I found that the zoom function is pointless with a Wavien collar because light that would normally go to the outer edge of the lens gets blocked as the lens is moved in towards the LED.

which piece is the collar ?

It’s in the box in the first picture, and upside down on the table in the last one with all the parts laid out. It looks like a reflective dish with the center missing.

Forgot to mention, I’m looking forward to seeing how you fare.

Some combinations just aren’t going to work with a pre-made collar, the aperture on the collar needs to work with the focal length and lens diameter (or aperture diameter), and if it doesn’t then the gains will be underwhelming compared to your expectations. If in doubt, try a lens with a similar diameter and longer focal length and see if output improves.

Where did you buy the 77mm high quality lens?

Looking nice. Is that a specific lense for the collar or can you use any?

Nice project. Look forward to finished product.

nice - subscribed!

I cut a new copper tube and used the 78mm lens. Fits like a glove with a layer of Scotch tape. I cut it long so I can just use a plate to sink the heat to the copper housing. That way I can install 2 18650 cells sideways. It’ll be much cleaner and tailstand great.

This is the best I can do for beam shots. I can’t figure out how to set exposure time so I edited the images to get them to show up. The beam is very bright white, maybe a little on the cool side but certainly not blue as shown. I’ll try to get some long distance white wall shots tomorrow. On the left is a negetive divergence and the right, focused to infinity:

Extra length for 2 horizontal cells instead of a protruding heat sink/battery tube:

Much cleaner looking :slight_smile: :

I got the lens with the longest EFL relative to diameter that I could find. Aspherics have an effective aperture (I think that’s what it’s called) which is usually somewhere around 85% of the total area. Is that what you mean by the lens aperture diameter? Outside of that (around the edge of the lens), the focal length is longer and can’t be focused into the spot. By adjusting the focal length out into some of the edge, you get a negative divergence which is what gives those pencil beams an hourglass shape. My 78mm lens seems about right because there’s only a small portion of the edge that doesn’t receive light. The 88mm lens caught light all the way to the edge and had a small effective aperture but very little light could be focused to the spot.

It measures closer to 77mm but it’s called 78mm here:

http://www.aliexpress.com/item/Free-shipping-Car-lights-optical-glass-lens-diameter-78MM-glass-led-lens-10W-100W-high-power/876692738.html

Mine seems to be good quality but it might just be luck of the draw.

For my next Wavien collared project I’ll be using this:

http://search.newport.com/?q=\*&x2=sku&q2=KPA049

Can’t go wrong dealing with that company :wink: .

See post # 15.

Cool light :slight_smile: Are you using a driver or is it direct drive?

You’ve got the right idea, it’s about making sure that the light coming out of the collar fully covers the clear aperture of the lens. 85% coverage on the back of the lens is about the right ballpark depending on the lens.

The problem with the larger lens is probably a combination of factors, but MEM would be a better person to explain why. He’s really the authority on lenses and collars around here, not many guys can equal his knowledge of them, I know I can’t. I can say that it’s shocking on the lenses I’ve tested how much output variation there is on lenses of the same diameter, not even including a collar in the mix.