will a inductive sensor work through a glass bed ?

will a inductive sensor work through a glass bed if I put a thin aluminium sheet under the glass ?

thanks Nikki

Unlikely - although I have tried thin aluminium foil underneath 3mm glass and managed to trigger the sensor. Unfortunately the sensor was almost touching the glass!

This experiment came from something I read on here - the sensors work best with ferrous metals, just about work with aluminium sheet, but will work quite well with aluminium foil - something to do with the way that the magnetic flux moves around in the very thin foil (non-technical analysis!).

Edited 1 time(s). Last edit at 06/08/2015 06:46AM by David J.

capacitative sensor might works, at least I read that here. the consensur I read about aluminium foil seems to be that it doesnt trigger reliably. search youtube for thomas sanladrer or something he has a vid a about how to make the sensor work.

Thomas says to use an aluminium plate instead of glass. Just ordered mine from Ebay.

Edited 1 time(s). Last edit at 06/08/2015 11:14PM by Ecky.

An aluminum plate under a 1/8" thick glass won't work, however, a galvanized steel sheet will. I believe the zinc has something to do with it because I tried polished steel sheets and the probe couldn't sense through the thick glass.

Edited 1 time(s). Last edit at 06/11/2015 02:54PM by gyronictonic.

The polished steel sheets weren't stainless, were they? I only ask because some forms of stainless are not magnetic...

David J, it was stainless steel cut from onlinemetals.com. The sensor does pick up the stainless steel but not as far as the galvanized. For some reason, my inductive sensor can pick up my stainless steel paint scraper from a good distance, which was where I got the idea to try a piece of steel under the glass.

One thing i noticed is that my inductive sensor can pick up the galvanized steel sheets from Home Depot better than the galvanized sheets cut from onlinemetals.com, both with the same thickness.

There's stainless that is magnetic (ferritic, or martensitic - a magnet will stick to it) and stainless that isn't (austenitic - a magnet will not stick, or only very weakly). The sensor won't get as much reaction from a non-magnetic type when compared to the magnetic type. Austenitic is the most common type, while martensitic is used for tools as it is tougher, can be machined, and heat-treated.

Try a magnet against your stainless steel sheet, then try it against your paint scraper.

BTW: I'm not saying that this is the definitive answer - it's just something to consider!

Edited 1 time(s). Last edit at 06/12/2015 12:22PM by David J.