The probe size with the One Touch I believe is about a size 10.
You are probably having difficulty getting the probe to even go into the hair follicles. It is my opinion however that 10 to 15 seconds is too fast for Galvanic to properly decompose the papilla of the hair. I would shoot for a setting of at least 30 seconds.
Scabs are an indication of overtreatment, which can quickly happen if treating many hairs that are very close to each other. I would very much recommend that you get a good book that covers Electroysis before doing much more to your body.
I am also somewhat concerned as to whether your hair follicles have enough moisture. That is because clients that I have treated always seem to come to me dehydrated. If you just pluck a hair does it have a moisture sheath along the shaft of the hair. You may need to use a good moisturizer and increase your hydration,, as galvanic works entirely by converting moisture into Lye which is what decomposes the hair.
With galvanic you generally do not need insulated probes, but if you are having scabs form it could be that the follicle is so dry that the path of least resistance is at the surface of the skin. If that is the case, you are not killing the hairs at all.
Also galvanic requires that the hair be in the Anagen stage, (actively growing stage).
I would suggust that you concern most of all with correct procedures and not rate of speed. The probe diameter should be about the same diameter as the hair shaft. Professional Probes are based on their diameter. Size 2 is 0.002 whereas a size 4 would be 0.004 an so on. So in this case the larger the number, the larger the probe. If you skin is very conductive, you may want to consider using an insulated probe, to cut done the conductivity at the skin surface. What is important is to have the bare portion of the probe at a depth where there is abundant moisture to convert to lye.
I hope this helps.
Martha Montgomery, CCE
Puget Sound Electrology