Got me new drill bits and I've finally been able to make some chips. Lordy, the alloy that Hammond is using nowadays is really gummy. I've even been having to scrape bits off the edge of my Noga deburring tool. Weirdly it files really nicely and doesn't gum up the files. Normally when taking a file to aluminium I'm reaching for the file card every three minutes, but not today. Well, I've got much more filing than drilling to do so I shouldn't complain. But die casting alloys are always a bit weird, they care more about shrinkage and clean quick freezing then cutting properties. Out of shear (sic) curiosity I'll have to see if they specify the alloy they're using.
You can see from the ragged edges of these chips that they're not exactly what you'd call exemplary.
![](https://www.eevblog.com/forum/testgear/test-equipment-anonymous-(tea)-group-therapy-thread/?action=dlattach;attach=1401284;image)
OK, they're not
terrible, but they're not exactly good either.
Oh yes, my nibbler's gone walkabout, so filing really is the name of the game today.
Anyway 1 1/2 rectangular holes left to do and then I'm finished. Got the worst one for the IEC connector out of the way, which is nice. Two corners of the mains switch and the complete voltage selector left to file. Ho hum, back into the fray...
Edit: Seems to be LM2M alloy (Al-Si10Cu2).