Thread: Spin Test

Hi Stuart,
On the TPG front, today I happened upon what I first thought was an 'unusual phenomena' - I was making hubs for cheap charlie exhaust fans that have been failing in some rentals. The flange was just a MS washer brazed to the hub. I had to machine the dia of the flange to fit the fan blade (qty 5 all up) - first 3 were fine, but #4 wore/broke the tip off the cutting tool - the perimeter of the MS washer had gone nearly as hard as the HSS. I then worked out that this must have been the last of the 5 to be brazed as they were all dropped into the coolant together and the temp of the last one must have been just right to harden it.

Well that's the long story of what I had to do next - use the high speed Dremel at the tool post to get that perimeter down. So now it looks like another project to make a proper mount to attach the Dremel to the tool post. The Dremel runs from 10k RPM to 30k RPM - just by hand, I was able to get a pretty good finish. Certainly opens up a few possiblities - why do we always look for ways to use something that just 'looks useful'?

Regards, Daryl

Hi Daryl,
Many people us dremals as TPGs, they seem to work pretty well, as you've found.
I picked up a variable speed dia grinder not long ago that I had planned on making into a TPG. First I'll try the big one and make an extra set of pulleys and an internal spindle. Fingers crossed.


Stuart