P718T Chimera build

Your about to find out, so are we! But it depends on what you deem good acceptable or not? But you do have avenues. I would start with diffusing the dome first, then the bottom of the reflector about 2mm up, certainly if the beam is ringy, then ever so lightly, stipple the reflector if not totally happy with the first 2 steps, IMHO. You can always hit it again it’s amazing what a light spritz of clear can do. :wink:

I have just diffused the dome on a few XHP50’s /70’s and in smooth reflectors and accepted the light cross it projected because the rest of the beam was really sweet! I have a XHP50 in a L2 with just a diffused dome that I will not touch even though this artifact exist in the beam, but to me most acceptable. It also depends on the reflector itself right, as in the position the emitter is at or to the reflector, focused, de-focused ect.

I had used and abused this Courui reflector to the point I was going to toss it, but when I changed the XHP50 to a XHP70 in the Super Courui, everything came together! Sometimes you get lucky! :smiley: :+1:

All the luck to ya, can’t wait to see how this turns out! :beer:

Photos delayed. Started out with no light and it took a while to find it was caused by a continuity problem with the tube coupling and now I have to figure out why the mode changes are flakey. Then comes solving the big dark hole and cross in the beam which is otherwise crazy bright with the 2s4p NCR18650Bs. Not ringy, just the cross and hole. Thermal path seems to be effective and on the highest level the head heats up pretty fast. Temperature step down happens at 2 minutes and again about a minute or so later so that’s one thing working properly.

I did a heavy stippling on the reflector I cut down and a light stippling on a reflector from a defiant 3d I cut down. The light stippling helped but there’s still a moderate donut hole in the beam. The heavy stippling eliminated the cross with no hole but it’s pure flood due to the way I cut the reflector. At 60’ it illuminates an area 80’ wide. I also suspect it should be brighter. When the meter I ordered arrives I’ll check the tail current. I suspect it is being limited significantly by the ground path through the tail board screws. If that is the case I’ll clean off the anodizing on the flats near the screw holes and make some copper clips and solder them to the switch side of the tail board for a better ground path. I found a 68mm wide 34mm deep 5° smooth reflector that should work well. I just need to reduce the diameter of the flat at the top by 3mm and remove the 0.8mm thick base and it should slip right in. Pretty much resigned to shaving the dome.

Still cobbling together parts to make a tailcap to fit over the switch.

Part of a run pulled loose from the rj tailboard while bending copper to improve ground path. I cut runs on a srk board and transferred the switch. Still minus jumper wire but ready for current tests.

Received the double springs from ebay seller. After a little cutting, bending, and streching they’re mounted on the tailboard
Tomorrow I replace the 7135 on the driver, re-wire, and test tail current. Looking forward to the arrival of the 5° reflectors.

The 5° reflectors were processed through usps isc chicago and are scheduled for delivery by 3/16. Looking forward to seeing what the xhp70 does with a narrow beam reflector. The narrow angle should produce good throw and eliminate the cross and hole.

The reflectors will be here monday! Waiting impatiently…

What reflectors are you going to use? Got a link?

I’ll be using this reflector

Hurry up Mailman! :smiley: :+1:

Really really interested in how this is going to turn out!!!

The reflectors were delivered monday as expected. I reduced the flat on the large end and filed and sanded the base off of one and stippled the other. Unfortunately while doing so I was less careful than I should have been and got debris in the first. Swishing it in a mixture of dish detergent and water, running it under the faucet to rinse, then rinsing again in distilled water left it reasonably clean and without major spots. The one I stippled developed a couple of dark spots from some kind of debris on the reflector when it was packaged - I just unwrapped it and sprayed.

The one I cut and installed did a pretty good job with the cross. At distances of less than one foot from the wall there’s a dark hole with a bright corona but as distance increases the beam changes such that at two feet there are four irregular dimmer regions and at 12 ft there are four slightly dimmer regions in the otherwise bright hot spot. This may improve after I remove the and re-install the emitter - it’s a bit off-center. I removed the star once already and if I do so again I’ll remove the emitter and reflow it to a new sinkpad. Arctic Alumina is a challenge to remove and I don’t wast ro re-use the star after removing AA from it twice. When this happens I’ll mount the star on a 3” dia piece of aluminum rod and test the emitter current. With 16awg wires to the emitter and 2x 18awg wires on the tail board it should be getting plenty. That will have to wait until the paste solder I ordered arrives. I also ordered four more of the reflectors. I thought of a way to do the modifications without getting debris inside if I do two at a time. The stippled one will serve as a form to help create a silicone insert to fill the space between the reflector and head.

I’ll post photos of the first attempt’s beam after the snow’s gone and I have a nice dark night to work in.

Tailboard wired

Off-center star


Crenelations mostly removed leaving slight dips in the bezel

New tailcap nearly complete. I cut the threads and a bit of the dividers from the rj battery tube at the tail end, drilled out the center of the srk cap to clear the switch, and jb’d the two together. Using the tail board mounting holes as centers I drilled holes for screws to reinforce the joint. Unfortunately screws prevented the cap from screwing in properly. Pop rivets did a bit better but I’m not satisfied. Looks like I’ll have to make some solid rivets from brass rod. The combined tailcap with the allen head screws tailstands nicely and offers attachment options for overhead use. This tail cap also has a drawback. I need to fab and mount an extension to the switch. I also need to fab a handle to attach toward the front to reduce the load on the tail and improve balance.

The reflector I’m using which has a lip as provides improved heat distribution through the head compared to the original rj reflector that just slipped into the opening in the head. The whole head gets warm in a period when the area ahead of the switch got hot.

After I’ve completed the tail cap I’ll replace the stainless tailboard screws with something better.

I sanded the bezel down a bit more so the lows are about 1/32” deep. Plenty of light leakage to show if I left it on headstanding. Tightened the two pieces of the tail a bit too much trying to align the tail cap and battery tube with the button and can’t separate them. This forced me to go a different way. I sanded down the front of the battery tube a bit and now the rj handle is inline with the button with the tail tight and the ‘straps’ on the battery tube are 45° from the 12 - 3 - 6 - 9 o’clock positions.

Next is the carrying handle. The balance point is slightly behind the center of the front battery tube with the current handle. I’ll be using a 4’ piece of 3/8” 1/16” wall stainless tubing I bought several years ago for a handle that will allow a handle mounted pusher rod to operate the side switch. It will be cut to 1/2 thickness where wrapped around the head near the switch then bent back toward thd tail where it will be secured. The ability to visualize complex objects and rotate and manipulate them to visualize them from positions and angles I choose that I developed during high school drafting classes is still useful.

Still waiting for the four additional reflectors I sent for but after using this light for a while I decided that the slight dimmer regions in the hotspot will improve when I fix the off-center position of the emitter. The additional reflectors will be used in (an)other project(s).

I purchased the 8x ncr18650b protected cells specifically for this light. After installing new tail wires to replace the wire damaged by fit tests with screws securing tail cap segments and arrival of the solder paste I ordered (from China) and reflow the emitter onto a new sinkpad I will measure the emitter current at different levels to determine approximate runtimes but I know the results will be good.

Too bad it’s so heavy or it would be an edc candidate :crown:

The more I use this light the more I like it. Spent some time adjusting the reflector. I didn’t consider that the reflector is suspended. When fitting I removed enough from the rim of the reflector when I also removed the base, and it’s providing enough clearance that by loosening the bezel and tapping the light I can adjust the reflector. A bit of caution tightening and a few tries and at about 15ft I have a bright center cross with four slightly darker regions in the hotspot. XHP70, cross brighter than the rest of the hotspot.

Anyone got a spare q8 driver?

Very satisfied with this reflector and glad I have more enroute.

Wouldn’t a multi-emitter zoomie be cool?

Reflector centered better than I could ever hope. Still waiting for 4x of the 5° reflectors to be delivered but they’ll be used for some future project. Considering a battery tube bypass using a piece of heavy copper wire to attach one side of the switch to a piece of copper at the head end of the tube to bypass the brass to stainless to aluminum junctions at the tailboard screws in the ground path with four contact points between the batt tube end and driver ground ring. With 16awg wires the xhp70 pretty much gets all the current it wants.

At this point this light has hit the target. Still cogitating the matter of a handle allowing removal of head or tail without tools… Took long enough but with my budget… still trying to scrounge up enough for the emitters for that contest entry… Beamshot comparison when I have more lights to compare.

Coming soon: 1000 post giveaway. Currently planned: S2, Dr J lucidrv, xm-l2 u3 3d or de-domed 1a. Host and emitter from RMM (or 1a de-domed by me), driver from Dr J. Simple, basic build and my curent edc favorite. Screw ring mounted driver (driver not soldered). Driver retaining ring hand-filed and sanded to clear components and installed using scissors. Will include smooth reflector and spare o-rings at gaw.

Final revision in the works. This light will be receiving a TA srk driver with 16 7135s and tactical narsil firmware. It will also get a new forward clicky 10A switch, maxtoch 32mm mcpcb to which a xhp70 N2 5C will be reflowed, and a new reflector of the same type with the only mod being a reduction in the diameter of the shoulder. I wish I could find a xhp70 3a or 3d but…

To be honest, I’m astounded by the performance with the fet +1 driver from RMM. The cells in it (2s4p ncr18650b protected) have not been recharged since it was assembled and though there has been an obvious drop in output from full charge to now to where turbo isn’t much brighter than the next lower setting, after many hours of use including several hours in turbo mode it continues to perform beyond expectations. Thermal step-down is currently disabled but when active it reduced output at about 5 minutes. With thermal step-down disabled I’d estimate the head hit and maintained around 75°C after 20 minutes in tailstand position.

Kaidomain has N4 3C 80 CRI

http://www.kaidomain.com/p/S024803.Cree-XHP70-N4-3C-Neutral-White-5000K-CRI80-LED-Emitter

Sorry, I just saw your reply. I find that I seem to prefer the a and d tints. The 2c and 3c I’ve used seem a bit greenish. I really like the color from lights I’ve used 3d in and suspect I’ll like the 3a xhp50.2 I’ll be using in the L5 (delivered yesterday). The 5a xhp70 isn’t bad but if I could find a 3a or 3d it would probably be a higher bin.

The maxtoch boards were delivered today. RMM was on the ball again. Two days from order to delivery. :+1: USPS from Utah to Ohio can be surprisingly fast.

By my estimates the 10A switch should be here by next weekend. With the new components (maxtoch mcpcb, 10A forward clicky switch, new 5° reflector, spring bypasses, TA ldo driver, and possibly sliced dome on the xhp70 the Chimera will be awesome. The trickiest part will be cutting the hole in the base of the reflector for the emitter without leaving debris inside.

Still evolving. 3 of 4 reflectors were junk but

Originally planned two hold-down points but broke off a tap (bottom hole). Rotated 90 degrees, drilled and tapped and on finding a hole not tapped deep enough attempted to tap deeper and stripped out threads. Re-drilled holes larger, filled with jb, and used self-drilling screws. Made copper retaining brackers but they shorted while adjusting mcpcb position. Replaced with brackets made from scrap jb weld. I mix in pill container lids and save the excess. The regaining brackets are a bit thicker than the flattened 14awg copper used to attach the 22awg wires to the 32mm maxtoch mcpcb to prevent contact with the reflector. Copper rtv silicone applied to wire mounting points as a precaution.

I was originally using a 5a xhp70 but neglected to re-clean before testing and ruined it. Replaced with an xhp70.2 5700k from the same source (rmm). Reduced wire size to emitters and eliminated a tailboard wire to limit current and attempt the 2-die syndrome. 22awg to emitter and on tailboard. A bit paranoid this time but

At less than 1 ft from the wall there’s a well-balanced dark 4 leaf clover pattern similar to my D01 but in a lighted room shining it at the wall about 12 ft away I automatically squint at power-up (turbo - 2s4p ncr18650b). This was the first mod started after joining. Finally near completion. Still need to figure out a better handle to support the head but facilitate battery replacement. Balance point is almost dead center.


The handle looks crooked but it’s straight. The light itself was at an odd angle.

Waiting for an xhp70 5c on a 32mm mcpcb from RMM. After a few months using the Chimera with the xhp70.2 I’m tired of the halo. In this light on a wall less than 12 ft away the effects of the cross on the beam are reduced by about 50% but the ugly corona isn’t worth the exchange. Upon receipt of the new emitter I will shave the dome and re-implement now downgraded tail mods. I destroyed a xhp50.2 in another light and implemented current reductions to prevent destroying the xhp70.2 here. Prior to the dust spot burn after improper cleaning after swapping the xhp70 to a maxtoch 32mm the effect of the cross on the beam was easily overlooked. It took over 20 minutes for the 2s srk driver from Lexel to step down. Good thermal mass and dissipation.

I did a wall comparison of my Q8 with the Chimera and though the brightnessess of the Chimera was a bit higher (with 8x ncr18650b charged over 2 months ago vs Q8 with freshly charged 30Q and third be-cu springs) I didn’t like the corona and feel it isn’t a proper comparison since the Chimera is currently a single-spring config using the same springs added as outers to the Q8. The hot spots were of similar size with similar total beam width and fade. While improving the Q8 I am also improving the Chimera and lacking a clamp meter and luminous testing fixture will rely on beam photos with fixed exposure values

Currently working with 6th reflector mod.