Before we can start cutting and drilling we need to know the dimensions of the base plate, if you’re planning on using your dry ice cooling power on a multiple platforms like S939 / S478 / S462 and LGA775 you have to pay attention to some size restrictions.
To keep the base plate compatible with LGA775 it may be maximum 5cm wide, otherwise it will be very hard to fit. Using an 2”1/8 copper tube will just about fit onto the base plate. For this example I used the following dimensions: Length: 6cm / Wide: 5cm / Height: 1cm.
Before we start brazing the copper tube onto the base plate it’s better to drill some holes, this increases the contact surface between the dry-ice liquid mixture and the copper base. Make 4-5mm deep holes with a 7mm drill in a nice pattern; be sure no to make holes outside of the “tube area” as this will look unprofessional afterwards.
So now we’re all set to braze our tube and base together. I started out by screwing the container to a metal bench, looking back, that was quite a bad idea as I ended up heating the bench instead of the container. In order to successfully heat up the container/tube you have 2 options:
- place the container upside down so when the heat rises it’s collected into the base and not the top of the tube.
- put it on something that does not touch the base completely.
In the photo below you can see I used a camping gas fire to heat up the copper and with the blowtorch at full power I can braze 3 containers like this, when only using the blowtorch I could braze only one container as the oxygen in the blowtorch runs out after 30min of full power. The camping fire uses propane and with it I can braze close to 3 hours.
You need to heat the copper until its cherry red, make sure you don’t melt the copper, and then apply the silfoss, and put the brazing rod between the base and the tube. Move slowly and apply some pressure, you will see it float; go around the tube until you are back where you started.
Finally, heat it up a little more, making sure the silfoss and copper merge properly, when that is done you have a super braze! If you have access to LN you can ask a friend to hold the hose into the container to prevent the forming of imperfections on the inside.
Here’s my first container:
And my 2nd revision :