Clearco makes a line of polydimethylsiloxane oils (silicone oils) with available viscosities down to 0.65 cSt, which is thinner than water.  I'd be curious to get a price quote.<br><br><a href="https://www.clearcoproducts.com/product/super-low-viscosity-pure-silicone-fluids/">https://www.clearcoproducts.com/product/super-low-viscosity-pure-silicone-fluids/</a><br><br>Sean<br>