A few months back I had commented that the reflector on my Acme Rotary didn't sit low enough to get a great beam and that the problems people had been having with ring beam patterns was a direct result of that.
It has been noted that the reflector has been redesigned, I don't know what has been changed so I can't really comment on that except that it sounds like Henry has dealt with the problem.
I'm not OCD about beam patterns but I like to tinker and this seemed like a fun project.
I had switched my Rotary over to a Nichia 219 but still felt that I could get a better beam out of it if the emitter extended up in to the reflector a little higher.
The easiest way to do this would be with a precision 3-jaw chuck on a lathe and remove some stock from the side of the stop on the reflector that faces the emitter. This would allow it to screw in a tiny bit more and fix the focus issue. The 3-jaw where I work walked off a long time ago so I had to raise the emitter from the other direction.
Removed the board again and made a .025" copy of it from copper sheet allowing plenty of clearance around the (+) and (-) posts to avoid shorts.
Slathered it up with thermal paste on both sides and reinstalled the board. The posts still came up high enough to solder properly and the back of the reflector didn't make contact with the solder points. I did need to file a bit off the top of the mounting screws to get the reflector down all the way.
.020" copper probably would've been sufficient but I didn't have any.
The emitter doesn't feel like it gets any hotter than before, the large board and good physical connection draws off the heat well. The head heats up just like before running it at 100% for a little while.
This method is time-consuming whereas removing stock from the reflector stop would take about 1 minute of actual work with a lathe.
I'm not posting this as an advertisement of services, (I get nervous with other folk's expensive lights!), but for informational purposes. I'm sure there are plenty of modders in here with access to a nice lathe who could do the work easily, - .020" off the back of the stop would probably do the job. You may still need to remove a few thousandths off the top of the screws. If someone already has it chucked up it would be a simple matter to go ahead and remove an equal amount of material from the back of the reflector for clearance of the screws and connections except for a small ring around the opening in the center.
If anyone has one of the newer reflectors and access to a depth micrometer or calipers with a depth gauge on the end I'd be curious to know what the distance from the back of the reflector to the backside of the stop is. Mine is .238".
The results of this mod are not Earth shattering, and I'm sure there will be those who argue that it's not worth messing with such an expensive light or that the copper shim will make the emitter run too hot. I just do this for fun. Ideally the back side of the reflectors will resemble the old ones with a raised section around the emitter hole to extend it down around the emitter while leaving clearance for the connections and screws.
Here are some beamshots comparing stock and modified. The phone-cam captured the ringy effect OK, (looks worse in person), but distorted the tints. The hotspot is tighter, the dark zone towards the outside of the spill is gone, and the bright ring at the outside of the beam is gone. Non-modded is stock emitter.
Stock:
Modded:
Both:
It has been noted that the reflector has been redesigned, I don't know what has been changed so I can't really comment on that except that it sounds like Henry has dealt with the problem.
I'm not OCD about beam patterns but I like to tinker and this seemed like a fun project.
I had switched my Rotary over to a Nichia 219 but still felt that I could get a better beam out of it if the emitter extended up in to the reflector a little higher.
The easiest way to do this would be with a precision 3-jaw chuck on a lathe and remove some stock from the side of the stop on the reflector that faces the emitter. This would allow it to screw in a tiny bit more and fix the focus issue. The 3-jaw where I work walked off a long time ago so I had to raise the emitter from the other direction.
Removed the board again and made a .025" copy of it from copper sheet allowing plenty of clearance around the (+) and (-) posts to avoid shorts.
Slathered it up with thermal paste on both sides and reinstalled the board. The posts still came up high enough to solder properly and the back of the reflector didn't make contact with the solder points. I did need to file a bit off the top of the mounting screws to get the reflector down all the way.
.020" copper probably would've been sufficient but I didn't have any.
The emitter doesn't feel like it gets any hotter than before, the large board and good physical connection draws off the heat well. The head heats up just like before running it at 100% for a little while.
This method is time-consuming whereas removing stock from the reflector stop would take about 1 minute of actual work with a lathe.
I'm not posting this as an advertisement of services, (I get nervous with other folk's expensive lights!), but for informational purposes. I'm sure there are plenty of modders in here with access to a nice lathe who could do the work easily, - .020" off the back of the stop would probably do the job. You may still need to remove a few thousandths off the top of the screws. If someone already has it chucked up it would be a simple matter to go ahead and remove an equal amount of material from the back of the reflector for clearance of the screws and connections except for a small ring around the opening in the center.
If anyone has one of the newer reflectors and access to a depth micrometer or calipers with a depth gauge on the end I'd be curious to know what the distance from the back of the reflector to the backside of the stop is. Mine is .238".
The results of this mod are not Earth shattering, and I'm sure there will be those who argue that it's not worth messing with such an expensive light or that the copper shim will make the emitter run too hot. I just do this for fun. Ideally the back side of the reflectors will resemble the old ones with a raised section around the emitter hole to extend it down around the emitter while leaving clearance for the connections and screws.
Here are some beamshots comparing stock and modified. The phone-cam captured the ringy effect OK, (looks worse in person), but distorted the tints. The hotspot is tighter, the dark zone towards the outside of the spill is gone, and the bright ring at the outside of the beam is gone. Non-modded is stock emitter.
Stock:
Modded:
Both:
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