Reading and fixing Chinese scales

[BillTodd]

I have made connectors for them, I've soldered 2mm(?) JRC box headed on them, in the end soldering a flying lead worked out best (I also junked the lcd and wrapped the whole case in adhesive backed foil to improve screening). Apparently the Chinese made lead is a poor fit in some scales (falling out at the slightest touch).

I hadn't thought of using magnets to mount the scale to the mill - It would certainly work but might attract too much swarf if not shielded well.

I have read all the info on 'reading' the data stream and thats a no brainer,

The problem is controlling the scale, to switch modes etc. (you really can't use the standard 300mS updates for a DRO) almost every type of scale I tried had a different sequence.

My PC & PIC based DRO project is here (if you haven't already seen it)

http://www.cnczone.com/forums/showthread.php?t=62704

I had to try and insulate them from the machine with Tufnol.

Insulating doesn't work (BTDT) I run mine on a separate supply biased to -1v5 so the scale +ve can be grounded. It works well - I've been using it today :)