The sizes of the LED-footprint are the same as in the datasheets. And the + and - contact is 0.5mm for 5050 and 0.7 for 7070.
I dont know if it can be realized this way.
It looks like the Ground/Thermal pad of the 7070 would short across the 5050 + and - pads.
I was talking about the clearances between all the pads and traces. You need a clearance of .16mm at minimum between all copper, a lot of times more then this is needed in order for solder mask to be applied so .2-.25mm is a much better goal for clearances between all copper since metal mcpcb’s are usually done with worse tolerances then normal pcb’s from what I saw.
The traces themselves need to be pretty beefy as well. A 1mm thick trace is roughly equivalent to a 31awg wire for reference.
The 5050-Pads had to be connected with jumpers or 0 Ohm resistors. Otherwise they are not connected.
Only green and orange is the relevant color for this mcpcb.
Im interested in using XHP 50.2 with Q8 if modding is easy without drilling. 6k on high and 12k turbo would be great!
2-4 pieces.
Okay, just realized that you made the Ground/Thermal pad (green lines) narrower in that area. All those lines of different colors made it hard to see that.
At the moment i do not really count how many boards someone wants. Because we have not a final product. But its good that we are moving forward with ideas. Its a lot to work out before we can get in contact with Banggood. But it is still good to see that people are interested. When the time is right (thats when we have a final layout) i will update the amount of boards that everybody wants. For now i only make a list of names that have basic interest in the board. Maybe the board will finaly not support the mod you want to do. So you would probably not buy it but for now (the layout is not ready) you still can be interested in this board. So for me it makes sense to wait untill we are a little bit further.
I hope that the design will still be including XM size 3Volt Leds when its ready. Its the easyest mod. You can use the original driver and you do not have to change anything regarding the Battery arrangement.
So this mod option could bring a few sells because its the easyest one that could be done by most of the people. From there on its getting much more work (but still doable and even without having access to a modern machine plant) and money.
Shure the best option would be, that the original light comes with a dual footprint board XP and XM size all 3V Leds. And the Mod board for 6V and 12V XHP Leds. But thats not going to happen.
Not sure if anyone posted prototype measurements of the positions on the MCPCB. Here's what I got:
Size: 38.04 mm x 2.00 mm
center to center for LED's: 23.29 mm
center to center of screw holes: 30.58 mm
outer LED edge to outer LED edge: 26.82 mm
center hole: 5.0 mm
As others noticed, if you tighten up that center screw pretty good before putting on the glass and bezel, it seems to center the LED's in the reflectors pretty good, better than how the Q8 came.
I sure hope these #'s can be confirmed/taken by at least one more person. Hate to mess up a run because of some mistake or typo... 
Center to center #'s are best guess on determining the alignment to center of the holes or LED's. Hhmm.. Should have taken inner, outer, and width #'s... Dang.
I’d be down for two.
I’d be in for a couple of these.
I’m liking TA’s idea. I have no problems drilling a hole in the shelf. I think most casual modders can handle this.
I’m getting two q8 with the intention of modding one, possibly more in the future. A high cri quad xhp50 sounds like a great mod
Thanks for the measurements! I was beginning to wonder if someone were going to get them for us!
Because it is getting quiet i wanted to ask the PCB Gurus if there is still someone working on a layout?
This project will kill Q16 imo 
Why everyone interested in xhp50.2? Would not xhp70.2 be a better choice?
I can work on the layout but there is not much to do until people figure out how it needs to be done. The only practical option that I can see is using one of the mounting holes for the ground wire pass through with the option to drill a separate hole so the mounting screw can still be used.
Basically the only change that involves is adding 3 holes to the outside of the pcb in the right locations.
The 70.2 will give you more light but it is also a harder mod since the reflectors would have to be modded to fit them. Plus they cost more.
Either setup driven hard will be way too much heat for the light as well.
I am not doing the work so i will not push for anything. But do we have a design ready or something that is close to be ready to get in contact with BG or BanL from KD?
I was waiting to hear back from people on if using the stock mounting hole is acceptable with the option to drill another hole before I wasted time on trying it out.
Since I am getting two Q8’s for myself, one to mod…
I am in for 1
I don’t know why you think we need a new hole?
We only need 2 holes for the cables and a third for the reflector-screw as on the stock MCPCB.
Perhaps we need two sets of two holes for the MCPCB-screws. And if they are too close to the solder pads, everyone has to drill them on the correct place.
Yes I would keep it s close to default mounting with the pads for wires and holes as possible, with two led pads turned in such a way wieselflinkpro drawed. The silk does need to be very clear I think