In searching for some grinder installation images, I came across a short Ernie Conover video on sharpening. About 1 minute into the video, he illustrates the sparks from HSS and carbon steel.

http://www.woodworkersjournal.com/us...turning-tools/


On Saturday, March 12, 2016 at 7:31:02 PM UTC-5, G. Ross wrote:
Bill Leonhardt wrote:
Hello Group,

My apologies. I used to follow this group, but I thought it folded. On a whim, I look today and I'm glad to see it's still alive. Perhaps you can help me with a turning tool question. I will also post to rec.woodworking.

I have three sets of full size (not for pen turning) turning tools. I don't know their history as I got each set from descendants of the original owners. I am trying to identify whether they have good steel and are worth keeping for my future turning aspirations. In the future, I expect to turn some furniture parts, a few bowls, but turning will not be the main part of my woodworking efforts.

I think the sets are pre-1980s and probably pre-1970s or even 1960s. They are described as follows:

Set1 (9 tools) - These have a label on the handle that says "Craftsman" (ala Sears) and that label could be a decal. It is well attached. The handles are wood and stained red. The steel is dull and looks, to the uneducated eye, as the same as I see on old, quality chisels. No markings on the steel.

Set2 (8tools) - These have a blue paper label on natural wood handles that says "Marples Made in Sheffield England". The steel is bright and some are marked (surface printed) with both imperial and metric sizes.

Set3 (8 tools) - These have the brand stamped into both the steel and handle, which is natural wood. The lettering says "Disston USA" with a keystone logo. The letters and logo in the handle are colored red. The steel is bright.

These all have some light surface rust, which should clean up fine, however the rust on the Craftsman tools gives me more a feeling of quality steel (gut feeling, not sure why).

Are there ways that I can evaluate these sets to determine if they have good steel and are worth keeping and using? Any insight you can provide is much appreciated.

Thanks,

Bill Leonhardt

You can tell somewhat by the sparks thrown off during sharpening. I
am not a machinist and do not remember the particulars but you can
probably look it up somewhere. Probably post the question in the
metalworking newsgroup would give you quick advice.

--
GW Ross

Between two evils, always pick the one
you never tried before.