:drool:

I hate to spoil your party, but I don't think your design will be very efficient. It is simple physics that dictates the rate of radiation from a body is directly related to it's surface area: Prad = r*E*A*T^4, where Prad is the rate of radiation, r is the Stefan-Boltzmann constant, E is the emissivity of the radiator (a value between 0 and 1, where 1 would signify perfect radiation), A is area, and T is temperature of the surface. Similarly, the ability for a body to absorb heat energy is governed by a similar law. By creating a high pressure high-CFM air flow, I'd imagine that you would be increasing E of the absorbing body (in this case the surrounding air), but that does not take away from the fact that a larger surface area of the radiator would increase the ability to extract heat energy even more. An SLK900 can acheive such outstanding temps by combining large Area with high pressure and flow (92mm Tornado fan). If I had the cash to purchase the whole line of SLK heatsinks, you would see the trend, since they all have similar construction. I would vary the CFM and pressure of the air, and you would see that the best combo is high pressure, high CFM, and large area. Also, for a way to adapt a 120mm to ~60mm opening, use a bell shape, instead of a pyramid. The bell shape will resolve the airflow in a straighter fashion than a pyramid, and if you add vanes to the exit of the bell, you could straighten the airflow even more. Unfortunately the byproduct of higher velocity = lower pressure...I'm not sure how that would work out with regards to temp changes, but it's something with which you may want to experiment.

:dome:

:D

Just to say it was a complete failure.
The fins are destroyed during the process.

You may close this now.

im not sure why im posting.. but make a good one and remeber not to use a shitti bent ryobi drill press

little late, but the acrilic, after working on it, can be repolished to transparency.
it can be done with solvents or temperature.

will paint thinner work? im not going to check cos ill have to open a whole new 40L drum

I believe it is acrilic solvent (a mix of cetone and else), it can be found in the net polishing acrilic (dont have the link, coss it was long ago).

I found that you should use sandpaper very thin, with water. finally metal polishing paste and a wet cloth (please, forgive my english, I dont know the exact vocabulary). have to be patient.


another is isopropilic alcohol (little)

the oven can be used (90 degrees celcius) for some minutes (depending on the thickness) but it can deform the material, and is more dangerous.

thnx