I'm not ashamed to say that I prefer Plastic to metal anyday. Over the years I have been careful with them and have never had a problem.
I don't de-meth as using a total of 13% methanol, I don't see the point.
With the TAM 120 I have checked the flow when filling the processor with oil at 11degs C and it is down to 34lpm. However the delivery pressure is massive.
After the methoxide is added, because methanol is not miscible with vegetable oil the resultant mix is opaque in nature. This effect will clear when the mix is about 75% converted. This to me is a good indication of the pump/processor efficiency.
In the past when I have used a weak pump this opaque nature of the mix can last 20 to 30 mins, resulting in KOH amounts of up to around 12gms/litre even on good oil.
With my present set-up even at ambient the opaque mix will clear within 5 mins and doing a 10/90 at this point in the process shows around the 85% conversion level. This is really the result of using a tam 120 with a 1/2" eductor.
The disadvantage of bio boy's very large processor as well as the pump he would use is that to heat the oil in a reasonable time he would need 2 if not 3x 3KW immersions.
It all can get too big to be practical very easily when doing things at home.
