I have received new SB-250, SG-250, LA-220, and SP-650. I installed the SB-650 and LA-220 on the machine and used them to regrind and hone most of my lathe tools. What I learned follows.
I did not see much difference between the SB-250 and and the SG-250. They both seem to be quite soft and wear extremely fast when grinding gouges and other narrow tools. Almost all of my lathe tools are HSS and I used light to moderate pressure on them but even with light pressure they developed grooves very quickly and before I could grade the stone to 1000 grit I had to resurface it to get a uniform surface on the stone. The stones also cut extremely slow. I also found that the new stone grader already shows wear so it will not last long. I wish this site had been around in the early days of this machine because the instructions for preparation of the leather honing wheel were too vague and I over oiled it and that was the reason for my disappointment with the performance of the machine. I used little oil on the new wheel and finally after 25 years or so got a razor sharp edge. If I followed the Tormek instructions the new wheel would not work either. Maybe it is the translation between Swedish and English but "impregnate with oil" means get the leather full of oil and that is exactly what you should not do.
I used to spend a couple of minutes on a slow speed grinder to sharpen a turning gouge and a couple of minutes longer to reshape one. It took 15 to 30 minutes to reshape a gouge on this machine depending on the size of the tool and how much shaping had to be done. The stone had to be resurfaced quite a few times. I have much sharper gouges now but I expect that the razor sharp edges are much more fragile and will not last abut a few seconds before they are no more sharp than a tool straight from a grinder. The sharper tools are nice for small work though. It took a very long time to surface both sides of a large HSS skew chisel.
My conclusion is that this expensive system is not very efficient both in terms of time and money. My machine finally creates a sharp edge but the instructions are still too vague and only say to impregnate the honing wheel with oil before use which will make it not work period. It would seem that after this many years someone would see fit to correct the instructions unless they are hoping the purchaser will ruin their new wheel and have to buy another. If I knew what I do now I would not buy this system.
I did not see much difference between the SB-250 and and the SG-250. They both seem to be quite soft and wear extremely fast when grinding gouges and other narrow tools. Almost all of my lathe tools are HSS and I used light to moderate pressure on them but even with light pressure they developed grooves very quickly and before I could grade the stone to 1000 grit I had to resurface it to get a uniform surface on the stone. The stones also cut extremely slow. I also found that the new stone grader already shows wear so it will not last long. I wish this site had been around in the early days of this machine because the instructions for preparation of the leather honing wheel were too vague and I over oiled it and that was the reason for my disappointment with the performance of the machine. I used little oil on the new wheel and finally after 25 years or so got a razor sharp edge. If I followed the Tormek instructions the new wheel would not work either. Maybe it is the translation between Swedish and English but "impregnate with oil" means get the leather full of oil and that is exactly what you should not do.
I used to spend a couple of minutes on a slow speed grinder to sharpen a turning gouge and a couple of minutes longer to reshape one. It took 15 to 30 minutes to reshape a gouge on this machine depending on the size of the tool and how much shaping had to be done. The stone had to be resurfaced quite a few times. I have much sharper gouges now but I expect that the razor sharp edges are much more fragile and will not last abut a few seconds before they are no more sharp than a tool straight from a grinder. The sharper tools are nice for small work though. It took a very long time to surface both sides of a large HSS skew chisel.
My conclusion is that this expensive system is not very efficient both in terms of time and money. My machine finally creates a sharp edge but the instructions are still too vague and only say to impregnate the honing wheel with oil before use which will make it not work period. It would seem that after this many years someone would see fit to correct the instructions unless they are hoping the purchaser will ruin their new wheel and have to buy another. If I knew what I do now I would not buy this system.