New build with recycled parts on a ridiculous budget 120cm*60cm work area

[Clive S]

None of my CNC modules get hot, i would think one fan would be ok, filtered inlet then fan with a vent at other side of cabinet.

Caps will/should not get hot or even warm.

They won't get warm until you put a load on them. I have two control boxes the router with 4 drives does not have any fans in the box is 500x500x250 and is fine.

[Neale]

It's easy to worry about overheating but in practice, it's not a big problem on our size machines. On mine, I have two 12V fans just so that they cover a larger area and push a bit of breeze across the stepper drivers but I have wired them in series so that they run fairly slowly. Moves more than enough air. Similarly, I run the 12V spindle cooling pump on 5V and that works fine as well.

I also bought a 50V transformer for my machine (from Rapid Online), then realised that it was going to be a bit too high. Once you take into account the fact that input voltage can be some way above nominal, and the output voltage is a few per cent high to allow for voltage drop at full load, then it's easy to start nudging that 80V. In my case, I rang Rapid the day after the transformer arrived and they were happy to swap it for 45V, and even arranged a courier to pick up the old one. Good people to deal with. I'm now running at a nominal 68V which is bang on the money.