Pocket size Espresso Machine with integrated alcohol stove.

Step 4 Considerations on the materials used for the build.

Some makers have commented on two possible problems they see with the build:
1) Lead in the solder
2) The use of copper and food.

The first is very easy to address: just use lead-free solder.

The second one, no so easy….the main concern is that the acidity in food will rust the copper, and the resulting salts are bad for your health.
This worried me enough to call a doctor (a family friend) and asked her to look at the Instructable and to give me her medical point of view.

She said that, in general, no to worry because:
a) Copper is not toxic and we need trace amounts in our diet. As a mater of fact, there is such a thing as copper deficiency.
b) Some copper alloys are in fact antimicrobial, which is why some hospitals have copper doorknobs.
c) As in all things, an excess of copper in your body is very bad for you
d) The brewing process is short, so the possibility of corrosion will be very small.
e) If corrosion does occur, the coffee grounds will probably trap it.
f) Tinning the brew head will eliminate any possible copper corrosion.