The new probe and finding the center of a hole

[cropwell]

As a poor old pensioner I can't afford a centre probe, so I am thinking about making one using QTC as the switching. I have some on order. If it works I will start a new thread. If it don't I will keep quiet !

QTC - quantum tunnelling compound, a polymer that changes resistance dramatically on deformation from 10**12 ohms at rest to virtually zero on deformation cost is about 30p per 3.6 x 3.6 x 1.5 mm 'pill'

[Ricardoco]

As a poor old pensioner I can't afford a centre probe, so I am thinking about making one using QTC as the switching. I have some on order. If it works I will start a new thread. If it don't I will keep quiet !

QTC - quantum tunnelling compound, a polymer that changes resistance dramatically on deformation from 10**12 ohms at rest to virtually zero on deformation cost is about 30p per 3.6 x 3.6 x 1.5 mm 'pill'

To be fair there are some really good plans out there for DIY probes that report to work very well indeed.

have a look here-
A DIY Touch Probe » fadedbits.com

Rick