New CNC Mill on the horizon

[fvfdrums]

The brush sections fit neatly under the bearings with enough clearance for some countersunk m5 screws to hold it down along the full run. Just haven't got round to that yet.

[fvfdrums]

Btw tool station are pretty good price wise on these brushes.

[njhussey]

Where did you get your brush strip from, how thick is it?

I wasn't quick enough!!!

[fvfdrums]

Right we are wiring up the psu. Transformer wired correctly giving 52 Vac. Connected to the Bridge rec at correct terminals. Output from the rectifier on the dc terminals is 45v ?? Shouldn't this be 70ish? Do we have a broken rectifier?

[Jonathan]

Have you put the capacitor(s) on the output of the rectifier? If not then that reading seems about right, as the meter is reading the rectified AC waveform, not a smooth DC output.

[fvfdrums]

Thanks Jonathan,

so we have now connected the caps up to the BR, on powering up to check what voltage we were getting instead of even getting there we got a huge amount of humming and some extreme heat through the negative cable coming from the BR so immediately turned it off.

any ideas what could be going on / we are doing wrong?

we have checked that it is definitely the +ve of the BR going to the +ve on the caps and the same for the -ve.

does there need to be a load on the PSU before we power it up?

[fvfdrums]

scratch that - problem solved, 68/69 Vdc now :)

[njhussey]

What was it?

[fvfdrums]

well, it was only one cap doing the crackling and humming so changed it out and works fine now so I think it may have been a dodgy one!

[Clive S]

well, it was only one cap doing the crackling and humming so changed it out and works fine now so I think it may have been a dodgy one!

or connected the wrong way round ..Clive