I made a Protective Case for Revopoint MINI.
you can download a 3D file from;
or
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That’s very kind of you and looks great , however you are covering on top the most hot area that Colling the processor , remember the aluminium helps to cool the device so covering it can increase the temperature of the device what could result in shutting down.
The top middle cold shoe is not necessary, the RGB camera is on the left not in the middle, so if you want a proper light for scanning RGB textures, locate the cold shoe directly above the RGB camera with a very slightly tilt to right .
Having LED directly above the Laser projector can interupt the Blue laser pattern projected on the object surface , use only warm colored LED light with MINI .
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I see.
Thank you for the useful information.
I will use it when I make the next version.
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@izoony some more information for you to help you with the next iteration.
Here’s a few infrared scans I made of the mini.
About 41° c was the highest I had seen it get to after it stabilized. He was running for about an hour when I took these.
The indoor ambient Air temperature was about 20° c
This picture is interesting bc in the center you can see the interference the scanner is having on the infrared sensor.
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I would not be happy with 41 degrees, it needs a fan!
I think a lot of normal electronic components are good to 80° c
@Miamijerry for sure cooler is better. Many years ago I had an air conditioned computer.
What is the maximum design temperature of this unit?
In your product testing how many degrees above ambient temperature should somebody expect this unit to run at?
MINI should be ok even reaching 60C according to actual testing , but I am afraid not all units can handle that .
My MINI RGB is shutting down the moment it reach 43-45C so no case for me unless heatsink or fan . My MINI Beta stays cool without issues ( no RGB)
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According to papers to maximum operating ambient temperature is 43-45C but in practice it is different from unit to unit .
From production tests the unit was still running at 60C ambient temperature
Selina is on holidays until Sept 13th
The center is where the protective glass is cut out so it sense the heat and the laser more intensive , but I am surprised by the temperature level in this place .
The normal case temperature is 40°C, so if the scanner is operating at normal power (5 watts) and the case temperature is 60°C, then the electronics inside are probably running above their rated temperature and will soon shut down or stop working correctly.
Following is my reasoning and a bit of math for those who want to confirm my estimates. It’s probably more than you want to read, but I had the time and the interest.
The temperature at the case only indicates the temperature at the semiconductor junction when constructed as designed. 40-42°C is 104-108°F (aka “comfortably warm”). 60°C is 140°F; for reference, it will cause 2nd degree burns in 3 seconds, 3rd degree burns in 5, so it is not “fine”, just as a safety concern.
The Thermal Resistivity rating (TR, in °C/W) was designed to result in a comfortable warmth at the top of the case, so if it is much hotter than that, and the power drawn is the same, then the TR is higher than designed (due to an assembly error, such as not enough thermal paste between the integrated circuit and the heat sink).
The upper Commercial Temperature rating for semiconductors is 70°C. This is at the junction where the electronics are operating, not at the contact surface with ambient air; devices can quickly fail when this temperature is exceeded. Industrial & Military ratings are significantly higher, but at a greater cost, of course. By “fail”, I don’t mean the electronics will burn out; they could just operate out of specification and not do what they’re supposed to do. More likely, the higher temperature will trigger thermal shutdown.
A quick estimation of the Thermal Resistivity of the scanner as an assembled unit can be made from the maximum ambient operating temperature, Ta(max) (40°C/104°F), the designed operating power, P (5 watts) and the maximum junction temperature for Commercial electronics, Tj(max) (70°C/158°F), minus a safety margin, Tm (gonna estimate 20°C).
Tj(max) - Tm = Ta(max) + P * TR
or
TR = [ Tj(max) - Tm - Ta(max) ] / P
This works out to 2°C/W (which just happens to be the typical rating for a Xylinx FPGA, so I’m taking this as a good estimate).
If the ambient temperature is 24°/75°F (room temperature) and the case temperature is 60°C with the power draw remaining the same, then TR has to have increased (meaning the internal heat sink is not working as designed). If TR increases from 2°C/W to, say, 9, then the maximum operating temperature of the electronics has been reached and normal operation can no longer be expected.
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Hi Jeff, you missed my point putting my words out of context , Revopoint production team put MINI inside a special testing ambient temp unit where it was working with the ambient temperature set at 60C after I was complaining my unit shutting down at ambient temp of 86F while testing in june , it’s internal temperature reached 45C and shut down the laser . I have somewhere pictures of that events , but now I am on my phone so if I find I will repost.
But all the testing under ambient temp of 60C don’t changed the fact that my unit still shutting down when reaching 45C , so I have a very small window to work with .
Officially the working operating ambients temp should be not higher than 43C .
But not for me and definitely not for @TinWhisperer .
Here we go Jeff , I found the pictures from the testing session of MINI , of course not all units can handle that as we already know . But that are the production quality issue . One of my latest POP2 can handle that temperature as well .
I wouldn’t think you would have any window to work with if the ambient temperature is 15°C above the shutdown temperature. Am I misunderstanding something?
60°C ambient operating for hours means Theta(JA), the Thermal Resistance from junction to ambient, is 2°C/W. That would place the semiconductor junction temperature at 70°C, just at the upper limit for Commercial electronics. That’s a reasonable design goal.
My unit is 15C hotter than the ambient temperature while working , Thankfully the hot days are over here … 
There is still heatsink option.
My latest POP2 edition is just working perfectly , almost zero heat production so no problem at even 30C ambient temperature. Just the way it should be .
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