Blowing air into flashlight is worse than across the outside.
The heatsink must act as highway for the heat to transfer out of MCPCB. This is conduction of heat transfer which is more efficient than convection. External fin need fan to do efficient convection transfer. Acebeam has nailed it.
Having cooling fins hang down from the led shelf and forcing air across it is absolutely superior to blowing it across the outside. I’m pretty sure they abandoned this idea and went with the much less efficient external cooling, but some people think they still may be forcing air through the light. I was hoping for confirmation one way or the other.
I meant the inside closer to led MCPCB shell needs thermal mass acting as sink for conduction of heat. Outside fins that connect to this thermal mass need convection of heat through moving air, so fan is useful here. It is less efficient to make many holes inside to let wind through because conduction is more efficient inside and close to MCPCB. Unless it is done to reduce weight, else i don’t see why Acebeam wants to make fins inside.
Wow the X70 throws farther and also more floody than the MS12 by a pretty good margin! I wonder if it’s because the flashlights were not aimed consistently. But if it is indeed a fair comparison, the X70 is much more powerful than the MS12. In some of those pics, it even throws almost as well as the R90C.
sorry,i dont have the link to the mod.i just know it because someone want to modify ms2010 and send ms2010 to the seller in taobao and change LED into xhp35hi. 贴吧404
this is the link(comparing ms12,x70)(sorry for my bad English)
Take a look at a computer cpu cooler ;). There is a lot of science behind them but there design let you understand it easily.
They dont have a lot of mass, instead they have a lot of surface area.
Cooling isn’t about mass, its about transfering the heat away from the source and being able to get rid of it quickly.
If you look at a cpu cooler, they have a solid base plate. Not to add mass as they are mostly not that big but to have an as big as possible contact plane with the cpu.
To move the heat away they, nowadays, rely on the use of heatpipes. They are far more effective than using conduction trough solid mass.
Quote from Wikipedia : “The effective thermal conductivity varies with heat pipe length, and can approach 100 kW/(m⋅K) for long heat pipes, in comparison with approximately 0.4 kW/(m⋅K) for copper.”
If you can not get rind of the heat quickly, like in a flashlight, then adding mass will help to create a buffer. More mass means able to ‘absorb’ more heat.
Moral of the story, the best cooling possible in a flashlight is having a fan directly on a cooling fin structure at the bottom of the shelf.
Are you sure? Look at the first comparison, the X70 illuminates all of the houses the entire width of the photo, whereas the MS12 only illuminates the houses at the center. In the second comparison, the X70 illuminates a much wider patch of trees than the MS12. The X70 looks alot floodier to me, which seem to make sense given the smaller head size.
Indeed the X70 does throw farther and looks more floody according the pics. I ordered both lights. Will definitely compare them to see which one is the best.