Bench Grinder Wheels

[Cross Slide]

I have a 8” Variable Speed Delta Bench Grinder

I’m trying to make it more useable. The tool rests are way to small and hard to adjust. They are pretty much Useless!!! Especially the one side that has a grove in it for drill bits. I wish it was just a flat plate like the other side. So I’m going to fix that issue after watching a YouTube video with the same grinder. 

The grinder came with Grey 36 and 60 Grit Wheels. I have heard that White wheels are better for grinding HSS Tool Bits. 

What Grits should I be looking for to grind HSS Tool Bits? 

This grinder is just for grinding HSS. I have another bench grinder for general work. 

I haven’t had much luck grinding my HSS and getting a good surface finish. I got thinking maybe it has something to do with the Grey Wheels and the Grits that came with my bench grinder.

Trevor

[f350ca]

The white wheels cut cooler, and are great for high carbon steel as in wood working chisels and plane irons but they aren't necessary for HSS, it will take a lot of heat. You won't be able to hold the cutter long before you get it hot enough to anneal it.
The wheels that come on grinders now are junk, not cheap but buy a good quality one and its night and day. 36 is good for roughing and I use a 120 for finishing, then hone on an oil stone,

[Dr Stan]

Go here: https://archive.org/details/machineryrepairm003995mbp and download the PDF of the Machinery Repairman 3 & 2, IMHO one of the best kept secrets in the machining world.  I was a MR in the Navy and this book was our go to source for everything.  It has an excellent section on grinding HHS tool bits.  It was also our study guide to prepare for our technical knowledge tests for advancement.  You also cannot beat the price.

BTW, start looking for a good used Baldor grinder on Craig's List.

[TomG]

The type of wheel has less to do with surface finish than the technique used when grinding the tool. Study the videos on YouTube (especially mine ) to learn the basic geometry and then practice, practice, practice.

I generally keep a 60 and 80 grit aluminum oxide wheel on my grinder and take a few quick swipes on a stone to polish up the cutting edge.

In my opinion, the rests are a safety feature to keep tools and fingers from being pulled into the wheel, NOT to rest the tool on. Once you develop a good feel, it will be easy to lift the tool off the wheel to check your progress and then place it back on in the same position. That also saves a lot of time adjusting and readjusting the rests. Check out any of my grinding videos to see how I like to do it.

Tom

[Clifford B.]

Hey Doc, I too was an MR aboard the USS Ajax, GO NAVY !!

[Dr Stan]

PM sent