Resistor options for Kaiju

[drewh1]

Probably a question for Paul

I am wondering if these resistors (Ohmite Metalmite89), mounted directly to the alumininum top plate would help to reduce ambient heat inside the Kaiju. Since the heat would be dissipated immediately through the alumininum plate, the heat exposure to the nearby caps might be lessened?

http://www.mouser.com/new/ohmite/Ohmite-89-Series-Resistors/



thanks,

[Paul Birkeland]

What ambient temperature do you have inside your Kaiju?  What ambient temperature would you like inside your Kaiju, and why?

Chassis mount resistors are very dependent on the chassis for heatsinking.  The 1K 25W chassis mount resistor that you've linked to requires 118 square inches per resistor for proper heatsinking (the chassis is 160 square inches). 

[fritzthecat]

I thought about this as well but forgot about as the chassis gets quite warm even without any mounted resistors heating it up further - I guess the only way would be to install additional heatsinks inside the chassis but this would again rise the temperature inside so additional ventilation slots would be necessary and that would not really look nice though I even could have them lasered by a friend. How warm does a Kaiju chassis normaly get at a normal ambient temperature of 20 degrees Celsius? I mean, it is summer and the ambient temperature affects this a lot.

[drewh1]

just back from camping!

So my concern is the Mundorf caps have a temp rating of 133 degrees. I measured the temperature inside the chassis with the following ambient temps.

71 ambient - 100 degrees around the capacitor, (near the resistor)
85 ambient - 112 degrees.

I am also moving to a location with temperatures that might exceed 85 at times.

My goal would be to keep the temperature as low as possible.  It doesn't sound like the resistors will help much without more heatsinking.

[johnsonad]

Which Munforf caps are you using? I looked at their data sheets and all of the caps they had listed had the same max temp of 185 F.

Tube gear gets hot. I've had amps that would raise the room temp by 10 degrees.  BH gear runs warm. Elevate the amp to allow more circulation. I use blocks and elevate them 1-2".  If you can help it, try not to worry about it. Tube gear runs warm, BH gear is well designed and ventilated, especially the Kaiju.

[Paul Birkeland]

If your room temperature exceeds 85F with regularity, this generally suggests an area where air conditioning is prevalent.

Still, you're well under the temperature rating you provided, though I can't find a Mundorf product that is rated that low.

[drewh1]

thanks for the responses. Air conditioning is pretty uncommon in california btw. I am not very worried and get that I am under the operating temps of the mundorf caps, just bored and looking for new stuff to change out   I'll probably leave well enough alone.