Adding capacitors to a Quark 125B

Originally Posted by GriffinRU

If you want it compact check this:
http://forum.rcdesign.ru/index.php?a...ntry&id=119589
http://forum.rcdesign.ru/index.php?a...ntry&id=119590
http://forum.rcdesign.ru/index.php?a...ntry&id=119591
http://forum.rcdesign.ru/index.php?a...ntry&id=119592
http://forum.rcdesign.ru/index.php?a...ntry&id=119593

Do you have dimensions of these parts? It would be easier to find suitable copper piece. Is there thermal paste between copper and outer aluminum case, too? Or is it good enough with just copper against aluminum?

Both mods here are excellent, I can't decide which one to choose...

[GriffinRU]

Originally Posted by hekekorte

Do you have dimensions of these parts? It would be easier to find suitable copper piece. Is there thermal paste between copper and outer aluminum case, too? Or is it good enough with just copper against aluminum?

Both mods here are excellent, I can't decide which one to choose...

I will get dimensions later'(I have .ems files), Mike made copper plates for me and I did the mod for him.
Yes, heatsink grease everywhere and copper plates were attached to Quark's case with screws to prevent PCB motion inside enclosure, common problem with Quark's.

[zeropointbug]

Yeah, I would just smother on the thermal paste, then tighten the screws and wipe up the excess that is squeezed out when tightened.

[GriffinRU]

eMachineShop files,

Originally Posted by GriffinRU

eMachineShop files,

Thank you GriffinRU for the .ems files. A 3d view shows that the another, heavier copper part is u-shaped, but in your pictures they both are flat. Are the flat ones just a simplier way to do the mod?

Zeropointbug: do you have dims for your clamp parts?

Generally: Would there be any sense to separate the power section from the brain section? To my knowledge it needs only some extensions to wires. It may be easier to put compact heatsinks to both fet sides and take the brain section which does not heat to more "safe" place to avoid short circuit and hit. Longer wires in this case are not length sensitive, I suppose? Just a thought...

[GriffinRU]

Originally Posted by hekekorte

Thank you GriffinRU for the .ems files. A 3d view shows that the another, heavier copper part is u-shaped, but in your pictures they both are flat. Are the flat ones just a simplier way to do the mod?

Zeropointbug: do you have dims for your clamp parts?

Generally: Would there be any sense to separate the power section from the brain section? To my knowledge it needs only some extensions to wires. It may be easier to put compact heatsinks to both fet sides and take the brain section which does not heat to more "safe" place to avoid short circuit and hit. Longer wires in this case are not length sensitive, I suppose? Just a thought...

You welcome,

Well, I was not sure which one would be easier to make. At the end two identical plates and two side panels complete the conversion. But you need to mill inside copper plate to clear electronics components on pcb. You can see that here. Also adding insulation tape was just to remind that you need to make sure that copper doesn't touch any electronics components.

You do not really need finned heatsink for middle fet's, what you need is means to squeeze two pcbs's tight and get transient heat from fet's to pcb as quick as possible. Quark's pcb is very thin and cannot accomplish that task, so you need to add metal bracket. Aluminum is not as good as copper, but you can try to do the same thing with stock heatsink plates, just replace foam with grease and you should be half the way to success.

Overall, you asked for dimensions, I think I provided a little bit more. You can customize this drawing to your like and so...

I have a 50x60x8mm copper plate for under fets and 40x40x3mm for upper fets (from processor heatsinks) which will be attached with 4 screws after milling the larger plate to get them together and enough room for pcb/fets.

I'm happy with the under plate but wondering if the smaller one can transfer heat well enough to the other one due to quite a small common area 10x40mm. I don't have larger one, so I have to use this. Let's see if it's good...

You gave me great info GriffinRU, BrianG and Zeropointbug. I wouldn't have even tried without them!