Radiator

The Automobile industry hold a lot of options for a radiator. You can walk
into a auto-repair/spare part shop and ask for a “cooling coil”, a
term the locals use to refer to these radiators that we can use. A new one may
cost around $ 50 or more, but an old one can cost very low or might even go for
free if they decide to dump it. The ones used for motorbikes tend to be smaller.
Here are some examples of the ones I’ve salvaged.

rad1 Water cooling DIY in Singapore

rad2 Water cooling DIY in Singapore

rad3 Water cooling DIY in Singapore

In order to use them, you will probably need to mod the inlets and outlets
a bit.

rad4 Water cooling DIY in Singapore

rad5 Water cooling DIY in Singapore

As seen, a hose barb is attached using cold weld epoxy such as JB weld first.
When the cold weld dries, a Layer of Marine Epoxy putty is applied all around
to strengthen the bond and prevent leaks.

 Water cooling DIY in Singapore

The cold weld epoxy and marine epoxy putty are readily available in most Hardware
shops.

Most of them are aluminum so you should add anti-corrosion coolant to the water
when you use it with a copper block. There are many such shops all over Singapore
and I frequent the ones near Kembangan MRT as they are within walking distance
from my house. They can be found along the road marked in red.

kembangan Water cooling DIY in Singapore