Yes, first two digits out of four (or three out of five) are tensile strength.
Yes, third digit out of four (or fourth out of five) is the welding position.
Last digit Zero means: cellulosic, sodium silicate binding, direct current, reverse polarity.
Last digit One means: cellulosic, potassium silicate binding, DC or AC, reverse polarity when DC (of course, AC polarity changes 60 times per second)
Last digit Two means: rutilic, sodium silicate binding, DC or AC, direct polarity when DC.
Last digit Three means: rutilic, potassium silicate binding, DC or AC, reverse and direct polarity when DC.
Last digit Five means: low hydrogen, sodium silicate binding, DC, reverse polarity.
Last digit Six means: low hydrogen, potassium silicate binding, DC or AC, reverse polarity when DC.
Last digit Eight means: low hydrogen with iron powder, potassium silicate binding, DC or AC, reverse polarity when DC.
MDG, in this Forum we don't criticize each other. We exchange opinions, and exchanging opinions is a very good way to learn something new every day.
Cordially
Giovanni S. Crisi