Toolpost grinder questions

Having used a few different TP grinders over the years there are things that add or subtract from success. First is rigidty, the more rigid the better, this will show in the surface finish right away, waves, scallops, lines, mean lack of stiffness. IMO mounting a TP grinder as pictured to a QCTP is asking for poor results. Mount a TP grinder to the compound, if that type can't be modified to do that don't buy it. Something not often considered is the lenght of the spindle from wheel to belt, a center in the TS is often needed on long work, but then the spindle hits the TS base, I doubt your mini lathe has the crosslide travel to clear the TS and twist the grinder to clear, and still contact the work.

If your lathe does not have reverse, you need a grinder that can be reversed, the wheel has to turn opposite the work, which means in forward the sparks from the grinder go UP. The wheel speed needs to be 5-7000 sfpm to work well, thats 15k rpm on a 2" wheel.

Having both a diamond and a boron stick dresser are necessary to get the best finish on the work. Each time you mount the grinder to the lathe it will be on a different angle to the lathe travel, the wheel needs to be dressed so the grinding face is dead nuts parallel to the travel of the carriage or compound or your finish will look like a poor threading job. When taking a deep cut which is a cut .002-4" you narrow the face of the wheel, because you have so little power to turn the wheel from these small motors. So on a 1/4 wide wheel should be an 1/8 to 5/32 wide in contact. Since you don't have the wheel spindle running parallel to the work, you only dress the corner this wide. For a finish cut of less than .001 you can widen the dress to 1/4 if the motor can handle it.

When dressing the wheel the type of dressing holder that can clamp to the work, or a chuck jaw is the best to get the face square to the work.

The speed of the work should be around 100 sfpm but is not critical, just in that range is good.

I currently have a Themac TP grinder 1/3 hp, and this is great on a 12" lathe, I had a Dumore before this and used it on the Myford S-7 quite a bit. It was a little 1/14hp with a 2" wheel, but did a great job just slowly. For a mini lathe that would be the ticket.

You could take the 150 for the LMS unit and add an equal amount, then buy a used Dumore, and be happy. IMHO

I recently added a 10" lathe to the shop that came with a Fims # 2 quick change tool post. I am not familiar with these like I know the Aloris but it looks to be very good quality. It only came with 4 holders and I would like more. I have been looking on eBay and I only see the larger sizes, no # 2 size. Does anyone still sell these? Does any other brand fit? I would like more of the A or B style and maybe some boring bar holders. Also the cut off, their E style holder is at an angle and seems to take a cutter .530" high ( that's what is in it now)..... The holder does not appear to be modified..... Was this meant for a 1/2" cut off or did they have their own special bit?

Thanks