For those of you who don't think you can use the Centri with t-tech cartridges. All you need to do is use a rubber bad on the a-bar to counter the resistance from the cart. I shaded a medium sized peacock today, with an 11mag at 6-6.5 volts and it worked like a champ! Just wanted to share.
I posted a vid on the Facebook rotary tattoo machine club if any want to see it in action. Thanks.