Zenfox T3 Triple channel dash cams free test invitation, limited quantity

The soc surface area is approximately 15mm x 19mm.

Problem is thickness. The 20x20 would cover entire SOC length wise but width wise is about 5mm too big. Also we don't know thickness. So I'm thinking of just going 15 x 15mm since they include 5 thickness in a pack.
 
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Doesn't look like being too big is a problem. You should be able to get the thickness by measuring the thickness of the pink gum, close enough for normal thermal paste to work. The less paste the better, but it doesn't need to be exact. Also, copper is soft, if you get it a little too thick you can sand it down fairly easily by hand.
 
Doesn't look like being too big is a problem. You should be able to get the thickness by measuring the thickness of the pink gum, close enough for normal thermal paste to work. The less paste the better, but it doesn't need to be exact. Also, copper is soft, if you get it a little too thick you can sand it down fairly easily by hand.

Well there was no way to measure that pink goop what so ever. Absolute abomination.

Thickness sizes are 0.3mm, 0.5mm, 0.8mm, 1mm, 1.2mm

I really am not wanting to spend time sanding these things down to fit. Nor do I know which will fit. There's really no amount of guessing to tell you how high the heat shield sits above the SOC / CPU.

At about 7-8 GBP per pack, I'm not going to lay out the equivalent of 35-40 GBP to find the proper 20x20mm size + another 10 GBP for the thermal paste. Anyone want to comment on proper size ill order that otherwise seems 15x15mm is the winner with a 5 size thickness pack.
 
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Maybe EGS can measure his gum, or put some alternative gum on to squash down to thickness, then measure that.
Looking at the images of the pink gum above, looks like 1.2mm would be the one.
Does it matter if the EMI shield cover doesn't go back on 100%? You can secure it with glue, or solder assuming it is tin plated.
 
Maybe EGS can measure his gum, or put some alternative gum on to squash down to thickness, then measure that.
Looking at the images of the pink gum above, looks like 1.2mm would be the one.
Does it matter if the EMI shield cover doesn't go back on 100%? You can secure it with glue, or solder assuming it is tin plated.

Yes it does. You need it to sit over the SD card slow and not make the heasink too tall to close the case. My rough guestimate, and it's really hard for me to see such small numbers is the heatshield stands 2mm tall and the the SOC is 1mm. So we're looking at .3-1mm without knowing how much space is in the void. So my guess would be .5mm or .8mm or MAYBE but probably not 1mm...But that's a guess.
 
The entire chip needs to be covered or there will be hot-spots which will limit it's operating temps. Cut bigger parts down to the needed size with saw, grinder, or shesars then put sandpaper face-up on a flat table with the edges taped in place. Rub one side of the cut piece in a 'figure-8' pattern till it looks consistent all over all the way to the edges. Flip the peice and do the other side the same way.

Window glass is better than a flat table and finer-grit paper will give a better surface, but the first way is good enough as long as you use good thermal paste.

Phil
 
The entire chip needs to be covered or there will be hot-spots which will limit it's operating temps. Cut bigger parts down to the needed size with saw, grinder, or shesars then put sandpaper face-up on a flat table with the edges taped in place. Rub one side of the cut piece in a 'figure-8' pattern till it looks consistent all over all the way to the edges. Flip the peice and do the other side the same way.

Window glass is better than a flat table and finer-grit paper will give a better surface, but the first way is good enough as long as you use good thermal paste.

Phil

Don't have saw, grinder, etc. Might be able to get sheers. I simply don't know the thickness we need. So if I am going to order 20x20mm i need to know the thickness. There's no multipack for those. I'm not shelling out what amounts to $8USD-10 per pack to see which one fits best. 15x15mm has multi pack with .3mm to 1.2mm sizes. 20x20mm comes one thickness per pack at $8-10 per pack currency wise.

Choices for 20x20mm thickness = .3mm, .5mm, .8mm, or 1mm. 1.2 is definitely too tall.

Maybe EGS will chime in with some guidance.

https://www.amazon.com/gp/B00OUJQVU0
https://www.amazon.com/gp/B07F3VHWY9
 
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Take piece with dimensions drawn on it to Home Depot or similar. Pull shears from display, cut piece, put shears back. Put piece back in pocket and smile at the pretty young checkout girl as you leave ;) Many adaptations of this technique and I have done similar more than a few times :ROFLMAO:

Phil
 
Does it matter if the EMI shield cover doesn't go back on 100%? You can secure it with glue, or solder assuming it is tin plated.
for the sake of testing I'd be inclined to leave it off for now, put the heatsink without the other stuff in the way and make sure it solves the overheating issue first, if it doesn't then there are deeper issues
 
Take piece with dimensions drawn on it to Home Depot or similar. Pull shears from display, cut piece, put shears back. Put piece back in pocket and smile at the pretty young checkout girl as you leave ;) Many adaptations of this technique and I have done similar more than a few times :ROFLMAO:

Phil

So I have an American penny which use to be 95% copper it says until 1982. Anyway, a penny will fit under the shield. Google tells me a Penny is 1.52mm thick. So I guess the largest plate we can buy is 1.2mm 20x20mm. So I guess that's an answer.

https://www.usmint.gov/learn/coin-and-medal-programs/coin-specifications
 
for the sake of testing I'd be inclined to leave it off for now, put the heatsink without the other stuff in the way and make sure it solves the overheating issue first, if it doesn't then there are deeper issues

For the sake of testing, we shouldn't have to be ripping the T3 apart to do what @Zenfox_Official's supplier and advisor should have done! Somehow we all got converted to engineer.

I'm remiss to leave off the emi shield. Then if we find there is interference, we're prying the thing back open again, cleaning off thermal paste, and back to reassembly.

Mine will be with a shield. Someone test without! What I did was move aside the tape so that the heatsink when mounted on the thermal shield will have proper coverage over CPU / SOC. Will order parts tomorrow.

Doesn't seem like copper plates come any thicker than 1.2mm. So there will still be a gap but I imagine with paste, it won't be horrendous. A few MM's. Not optimal, but also not sure where we're getting a 20x15mm plate cut to size either.
 
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for the sake of testing I'd be inclined to leave it off for now, put the heatsink without the other stuff in the way and make sure it solves the overheating issue first, if it doesn't then there are deeper issues
How do you mount the heatsink securely so that you can test it in the car?
 
How do you mount the heatsink securely so that you can test it in the car?
with the same goo you would anyway, only talking about testing, not a long term fix, not sure the issue is actually going to be resolved like this

anyone know what hardware is being used in the 3 channel Vantrue model?
 
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NT96660 according to one source

Phil
 
So to answer everyone's questions:

@Nigel thermal paste is like glue. It'd adhere the heatsink to the SOC/CPU. Per the Penny, See photo. Not big Enough. Also it's 95% copper and 5% tin pre 1982 per google. I have one somewhere. That's a newer one that's 97.5% zinc



@jokiin

1. Does the Street Guardian utilize an EMI Shield?

2. If the EMI shield is removed, couldn't the T3 wreak havoc on my electronics in the vehicle? I.E. it sits side by side to my Viofo.

3. If I install the EMI Shield and purchase a 1.2MM copper Plate, can I fill that Gap Space between the Plate and EMI shield with Thermal Paste? As I believe the actual gap is closer to around 1.7mm. I don't think double stacking copper plates is an ideal situation. Plus if I order them, I'll just get the 1.2mm

Here's Photos of what it'd look like if ONLY Heatsink was mounted to Copper Plate. Mind you, there's no copper plate yet.


 
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So to answer everyone's questions:

@Nigel thermal paste is like glue. It'd adhere the heatsink to the SOC/CPU. Per the Penny, See photo. Not big Enough. Also it's 95% copper and 5% tin.



@jokiin

1. Does the Street Guardian utilize an EMI Shield?

2. If the EMI shield is removed, couldn't the T3 wreak havoc on my electronics in the vehicle? I.E. it sits side by side to my Viofo.

3. If I install the EMI Shield and purchase a 1.2MM copper Plate, can I fill that Gap Space between the Plate and EMI shield with Thermal Paste? As I believe the actual gap is closer to around 1.7mm. I don't think double stacking copper plates is an ideal situation. Plus if I order them, I'll just get the 1.2mm

Here's Photos of what it'd look like if ONLY Heatsink was mounted to Copper Plate. Mind you, there's no copper plate yet.


Holly darkness!!!
 
Holly darkness!!!

I've got the camera setup on a desk and the lighting sucks being that it's night time. None the less, you get the point that it's possible to mount the heatsink onto the SOC / CPU.
 
You could use 2x 0.8mm plates stacked. If your measurements are correct?
You wouldn't lose much heat transfer at the join between the plates, better than having extra thickness of paste.

I think the EMI shield is required.
 
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