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I still need to cut the water passages but so far it's coming out pretty well.
Look up basic heat sink theory on the internet. You have a lot of metal there but not nearly enough surface area. Your transistors will create localized hotspots and more than likely overheat. You need surface area to exchange heat to the atmosphere. I haven't made any calculations but I also think that single fan radiator ain't gonna cut it. You may want to look into triple 120mm fan or dual 140mm fan units.

There is always forced air through a box section extrusion like the pro amps used to use.
 

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1) the radiator will mount just below the top cover there will be vents

Maybe I am missing something, but are you SURE that there is enough airflow to cool that LC radiator when it is mounted INSIDE of the amp enclosure ?

ALSO hoping that you are planning on using industrial grade pipe dope when making the connections to it inside the amp....you wouldn't want that puppy, or any of its connections, springing a leak in there.
 

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Discussion Starter #43
Look up basic heat sink theory on the internet. You have a lot of metal there but not nearly enough surface area. Your transistors will create localized hotspots and more than likely overheat. You need surface area to exchange heat to the atmosphere. I haven't made any calculations but I also think that single fan radiator ain't gonna cut it. You may want to look into triple 120mm fan or dual 140mm fan units.

There is always forced air through a box section extrusion like the pro amps used to use.
Thank you I really appreciate the input. I've looked at through extrusion forced cooling just not for this. and according to the manufacturer of the board the optimal temp that the heatsink should be is 80°C. there is still the plates that are going to be bolted to the outside of the heatsinks to seal the water passages. I thought if it gets to hot I could put fins on the outside sealing plates. or maybe change the flow rate of the water to let the water absorb more heat. or enlarge the water passages.
 

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Discussion Starter #44
Maybe I am missing something, but are you SURE that there is enough airflow to cool that LC radiator when it is mounted INSIDE of the amp enclosure ?

ALSO hoping that you are planning on using industrial grade pipe dope when making the connections to it inside the amp....you wouldn't want that puppy, or any of its connections, springing a leak in there.
Yeah I plan on making a lot of air flow vents and I found G1/4 fittings that computers use in there water cooled systems
 

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Discussion Starter #45
the heatsinks that I have pictured don't have the water passages machined in them yet I ran out of time today that's why there is not that much surface area on the outside because they are getting cooled internally.
 

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80 degrees... I am sure that is the operating temperature of the MOSFETS. This is not the same as the temperature of the heatsink at the MOSFET. And it certainly isn't the same as the overall temperature of the heatsink.

I have built Pass designed Class A amps. The designer uses an overall heatsink temperature of 40/45 degrees as a ballpark, as I remember. You are just not going to get any substantial power output without that overheating. It is just not enough heatsink - even for 10w per channel. If you are still aiming for 40-60w per channel, you need to rethink.

It is lovely craftsmanship, but there really needs to be some calculations done...

(Actually, you can get decent power output from it, as it is. But it will be 90% in Class AB...)
 

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Discussion Starter #47
well I did mill out the water passages on one of the heatsinks. maybe the manufacturer had a typo on the temp I can contact them. here is a picture of my idea on the heatsink
292006
292007
 

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Discussion Starter #49
80 degrees... I am sure that is the operating temperature of the MOSFETS. This is not the same as the temperature of the heatsink at the MOSFET. And it certainly isn't the same as the overall temperature of the heatsink.

I have built Pass designed Class A amps. The designer uses an overall heatsink temperature of 40/45 degrees as a ballpark, as I remember. You are just not going to get any substantial power output without that overheating. It is just not enough heatsink - even for 10w per channel. If you are still aiming for 40-60w per channel, you need to rethink.

It is lovely craftsmanship, but there really needs to be some calculations done...

(Actually, you can get decent power output from it, as it is. But it will be 90% in Class AB...)
Do your Pass designed Class A amps sound good.
 

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Discussion Starter #52
80 degrees... I am sure that is the operating temperature of the MOSFETS. This is not the same as the temperature of the heatsink at the MOSFET. And it certainly isn't the same as the overall temperature of the heatsink.

I have built Pass designed Class A amps. The designer uses an overall heatsink temperature of 40/45 degrees as a ballpark, as I remember. You are just not going to get any substantial power output without that overheating. It is just not enough heatsink - even for 10w per channel. If you are still aiming for 40-60w per channel, you need to rethink.

It is lovely craftsmanship, but there really needs to be some calculations done...

(Actually, you can get decent power output from it, as it is. But it will be 90% in Class AB...)
292113
 

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Discussion Starter #53
292127
292128
292129

I'm putting machined brass solder connectors on the board. the original terminal blocks were really flimsy. I really like making the parts but the brass connectors are going to be a pain to make I have 19 more of them to make. and once again I really appreciate the input that you guys give me.
 

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View attachment 292127 View attachment 292128 View attachment 292129
I'm putting machined brass solder connectors on the board. the original terminal blocks were really flimsy. I really like making the parts but the brass connectors are going to be a pain to make I have 19 more of them to make. and once again I really appreciate the input that you guys give me.
Why did you do this? How are you going to attach wires? If soldering then why didn't you just solder wire to PCB?
 

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Soldering is not one of your strong points :)
 
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Discussion Starter #57
Why did you do this? How are you going to attach wires? If soldering then why didn't you just solder wire to PCB?
Soldering is not one of your strong points :)
Why did you do this? How are you going to attach wires? If soldering then why didn't you just solder wire to PCB?
The holes are only .054" in diameter in the board the wire is larger in diameter. I will be able to solder the wire into the brass there is a hole for the wire to go into. It probably doesn't show very well.
 

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Hands with age or from constant tool/coupling vibrations is an issue for tradesmen. My hands at 41 can quiver if I were to hold them up to show steady or not. Those are working hands and probably a fair bit older than mine. You earn the shake. I bet we are all mostly solder suckers! haha
 
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