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

[Davek0974]

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.

[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.

[Desertboy]

I'm going to fit a inrush current limiter ntc thermistor
https://www.ametherm.com/blog/inrush...s-got-you-down

I think this is suitable
https://www.ebay.co.uk/itm/282728849186

as far as I can tell I just wire this inline to the mains, anyone had any experience of them?

[m_c]

I wouldn't bother, unless the power on surge is a problem, as it's just something else to give potential problems.

[Desertboy]

Looks like I'm going to have wait at least another day the AM882 will come from China quicker lol


Been on phone will either be redelivered tomorrow (If it's ok which it will be of course, things are like house bricks) or new one sent out for Monday

[Desertboy]

My Hermes claimed they tried to deliver it today although I was there with the roller shutter door open so they are lying bastards, have to wait till Monday, would have been quicker to order from China lol.

Using the 50v transformer as a pattern (the 45v will be identical) so started to think about kitting out the box, anyone see any issues having the transformer under the stepper driver? I am going to fit 2 pc fans one sucking in and 1 extracting.



Going to use new capacitors as I have them and am going to need to fit everything a bit tighter.

You can just see the breakout board in the corner on a bit of ply will fit it roughly there and chop a hole with a cutting disc for the parallel port and USB to stick through.

Not sure I will fit the other BOB as I really don't need extra the input pins, good to have a spare though.

What's everyone set there AM882's microstepping up at?

[Desertboy]

Transformer came finally! didn't get round to soldering it but will have it up and running tomorrow ;)


Damn just realised I wired this up wrong lol but turned it on yet. The orange and black should be joined as well as the red &yellow.

Was tired this evening only just come home from work glad i decided to leave it till morning.

[Desertboy]

Almost there, got some connectors on a din rail for sorting out the wiring to the BOB, still need to solder the capacitors but will get that done tonight. Looking for my holesaw set at moment so I can make the fan holes in the enclosure.



The non working AM882 isn't bolted down just there for reference.

I have got a current inrush thermistor which hopefully is the right one if it cause problems I'll ditch it but it was £2 so I thought worth a punt. Hopefully with one fitted I can then use a type B mcb which I can just fit in the box ;)

I now feel it's starting to look like cnc electronics ;)