bmatic
Posts: 8
Joined: Fri Dec 28, 2018 9:43 am

Armor case question

Thu Sep 19, 2019 1:30 pm

Hi, I got myself an armor case for my Raspberry Pi 4, and my question is:
Should I scrape black color with super fine sand paper from these parts that sits on processor, and then fine polish it ?
Would that be better in sense of thermal transfer between armor case and thermal pads ?
Armor case.jpg
Armor case.jpg (105.92 KiB) Viewed 1165 times

pica200
Posts: 246
Joined: Tue Aug 06, 2019 10:27 am

Re: Armor case question

Thu Sep 19, 2019 2:06 pm

No, the thermal pads bridge any gap. The heat dissipation of the SoC is so low it doesn't matter. But there is one thing you can do to increase the effectiveness of this case by a lot: Buy proper thermal pads. The included ones are garbage and have useless adhesive on them which insulates more than it conducts.

bmatic
Posts: 8
Joined: Fri Dec 28, 2018 9:43 am

Re: Armor case question

Thu Sep 19, 2019 5:20 pm

OK, so the paint coat on the case part where it touches pad does not metter ?
Thank You for information.
Can You please recommend high quality thermal pads ?

pica200
Posts: 246
Joined: Tue Aug 06, 2019 10:27 am

Re: Armor case question

Thu Sep 19, 2019 5:35 pm

I have Arctic Thermal Pad on my Pi/case. Pretty much any 6-7 W/mK or higher thermal pad will do. Higher is more expensive.

bmatic
Posts: 8
Joined: Fri Dec 28, 2018 9:43 am

Re: Armor case question

Thu Sep 19, 2019 5:47 pm

Thanks.
Do You have this kind of Armor case ?
I ask this because I just Googled "Arctic Thermal Pad", and I see there are pads with different thickness, which should I buy ?

Heater
Posts: 17419
Joined: Tue Jul 17, 2012 3:02 pm

Re: Armor case question

Thu Sep 19, 2019 5:53 pm

That "paint" is no doubt not paint at all but rather it is anodized aluminium dyed black. https://en.wikipedia.org/wiki/Anodizing. As such it's so thin I would not worry about it being any kind of thermal insulator.

I would prefer thermal paste rather than thermal sticky pads but I gather if you don't use the sticky pads there is an 0.5mm gap between chip and heat sink which could so with filling with a copper shim. A thick layer of thermal paste might be as bad as a sticky pad.
Memory in C++ is a leaky abstraction .

pica200
Posts: 246
Joined: Tue Aug 06, 2019 10:27 am

Re: Armor case question

Thu Sep 19, 2019 6:03 pm

Yes it's anodized and yeah, there is a gap. There are many clones around of this case and they are milled with varying tolerances. A thermal pad is the easiest and just works™. A copper sheet + thermal paste may work but no gurantee.

sparkyhall
Posts: 168
Joined: Mon Aug 27, 2012 9:14 am

Re: Armor case question

Thu Sep 19, 2019 6:05 pm

I have an Amor style case I bought on ebay, the gap between the CPU and the raised part of the cased measured just under 1.2mm and the pads that came with it were 1.3mm. I used a 1.2mm piece of aluminium and thermal paste on mine.

Having said that I'm sure mine had a gap between the two raised parts of the top section and the two pads that came with the kit were identical in size. I guess there are different versions of the case so it will better measure the one you have.

User avatar
RPIgoodSBC
Posts: 127
Joined: Tue Mar 20, 2018 11:37 am

Re: Armor case question

Thu Sep 19, 2019 6:17 pm

I have the same case.
You can read my comment about it here...

https://www.raspberrypi.org/forums/view ... &start=325

1mm thick thermalpad is ok.

Heater
Posts: 17419
Joined: Tue Jul 17, 2012 3:02 pm

Re: Armor case question

Thu Sep 19, 2019 7:43 pm

My feeling is that a millimeter of pretty much anything between chip and the metal of a heat sink is far from optimal. A copper or aluminium shim would be better.

I'm yet to be convinced that any of the funky pastes and stickies are anywhere near as conductive.

But I have yet to do the measurements so I guess if it works well enough it's good to go.
Memory in C++ is a leaky abstraction .

LTolledo
Posts: 4814
Joined: Sat Mar 17, 2018 7:29 am
Location: Anime Heartland

Re: Armor case question

Thu Sep 19, 2019 8:20 pm

my setup pictured is RPi4B version
RPi4B-4G_Armorcase-open.jpg
RPi4B-4G_Armorcase-open.jpg (200.56 KiB) Viewed 982 times
I never use pads over the SoC, use thin copper sheets.
thermal paste on copper to armor case, thermal grease on copper to SoC
get about 10C lower temp than with "insulator pads"
RPi4B-4G_Armorcase.jpg
RPi4B-4G_Armorcase.jpg (195.05 KiB) Viewed 982 times
and fan not/never get power from GPIO (I need the GPIO headers open for HAT use)

same method is used on RPi3B+ and RPi3B versions
"Don't come to me with 'issues' for I don't know how to deal with those
Come to me with 'problems' and I'll help you find solutions"

Some people be like:
"Help me! Am drowning! But dont you dare touch me nor come near me!"

adpi
Posts: 9
Joined: Mon Feb 24, 2020 9:14 pm

Re: Armor case question: no space for flat-cable connector

Fri Jul 24, 2020 7:27 am

Dear Amor users..

I need to hookup a breadboard to my 2 fan Amor cooled RPi 4

I'm using regular 40pin flat-cable including connectors. Unfortunately there is no space to get the connector on the RPi pins due to lack of space on each side of the Amor unit surrounding the 40pin space, about 1.5mm short on each side (1/18" or so..) See attached pic

Should I find an "extension" F/M strip to lift the pens above the frame to provide pace for the flat-cable connector?
Find smaller connector?

Thanks,
adpi
Attachments
AmorConectorSpace.JPG
AmorConectorSpace.JPG (32.56 KiB) Viewed 436 times

LTolledo
Posts: 4814
Joined: Sat Mar 17, 2018 7:29 am
Location: Anime Heartland

Re: Armor case question

Fri Jul 24, 2020 10:39 am

Extend_headers.jpg
Extend_headers.jpg (209.9 KiB) Viewed 435 times
"Don't come to me with 'issues' for I don't know how to deal with those
Come to me with 'problems' and I'll help you find solutions"

Some people be like:
"Help me! Am drowning! But dont you dare touch me nor come near me!"

adpi
Posts: 9
Joined: Mon Feb 24, 2020 9:14 pm

Re: Armor case question

Fri Jul 24, 2020 12:40 pm

Thank you LTolledo!
I even used your pics to show my issue :D
Cheers,
adpi

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