HSS tool blanks

mikey said:
Not sure if they're making bits or not but you will find them for sale on ebay.

My best advice - buy some mild steel keystock in the size you plan to use and learn to grind tools with that. When you can grind a tool shape you are satisfied with then change to M2 HSS. When you have M2 tools that work as you intend, try cobalt or the Tungsten tools. Trust me; grinding cobalt as a first tool does not usually work out well. They take more skill to grind well.

Clearly, Chinese bits are the cheapest way to go. My experience is that they do not hold an edge as long but they work pretty well. When I experiment with a tool, this is what I use until I get it exactly right. Then I grind one from a blank I trust.
Click to expand...
When I took a machine shop class in high school, we were given a piece of key stock to grind into a roughing tool with ground in chip breaker; when we could show the teacher we were capable of grinding an acceptable tool, we were given a new tool bit to keep for the year's classes; that and a round nose tool were our cutting tools for the class. He also had U shaped adaptors so that the 1/4" square tool bits could be used in the Armstrong tool holders for the larger lathes that used 3/8 square tools.
I had one of the best teachers ever, this back in 1962-3 at Napa High School Ca., Paul Goldberg, later changed to Kreuger. He apprenticed at Mare Island Navy Yard in the 1930s and was an apprentice school teacher after that until after WW2 when he taught in the public schools. Nothing went on in HIS shop that he was not aware of; he had a finely tuned ear to noises that meant trouble, and was on top of everything, and no screwing around in class!
 
Sounds like a remarkable experience, I love the older guys.
 
Funny story about key stock, my boy came over one night to make a part for one of his projects and grabbed one of the pieces of key stock I had practiced on and proceeded to attempt to cut down a piece of cold rolled shaft. about the time he found that it wouldn't cut I walked in. He said to me that he thought I better keep practicing grinding tools because even though this one looked pretty it didn't cut worth $#!#. We both got a good laugh when I told him it was just key stock I practiced on. and an even bigger laugh when he told me he had used that same "tool " to cut some delrin two nights before!
 
Reeltor said:
One thing that you might want to consider is to use an angle grinder to rough in the bit before taking it to your bench grinder.
Click to expand...

I've not used an angle grinder to rough in tools but I have used one with a cut off blade to rough in threading tools. Threading tools often have one side with a lot of material to take off and I tried cutting the bulk of it off with an abrasive cut off wheel. It worked but that tool got HARD. It took some grinding to get past that hard surface but it did save a little bit of time.
 
In my opinion , you will need a range of different tool blank sizes, even if you are using carbide tools. Sometimes you use a small bit because you don't want to spend a day grinding a 1/2" one. Other times you need a 1/2" bit because you need the extra cross sectional area to minimize flex because of the stick out required. I keep 3/16", 1/4", 3/8" & 1/2" blanks in my tool box, but I use 3/8" the most.
 
Thanks Dan, good thoughts.
 
Once a year or so I go shopping on eBay for HSS tooling. Often you can buy a large batch of tools, formed into all sorts of shapes, for pennies on the dollar. I've never worried about what grade they are, as some really old bits have been the best cutters. Wouldn't hurt to take a look and buy a batch for $10 or $15 bucks that have already been ground for left and right hand turning, plunge cutting, rounded edge for yellow metal, etc.

Glenn
 
Glenn I will keep my eye open there, I need to learn what to look for, and the strategies involved.
 
Aukai said:
Glenn I will keep my eye open there, I need to learn what to look for, and the strategies involved.
Click to expand...
One good resource is south bends old " how to run a lathe" book. Plenty copies around on eBay. The book has several pages dedicated to HSS tool geometry. Pictures and description of use. Also available on line.

Basically you will want to explore which tool shape to use for left and right hand cutting, also what to use to the face off the work mounted in the lathe. The next stage will get you into looking at the subtle differences in the tiny little rounded edge that contacts the work, and honing the sharpness of the tool edge.

Jump in and have fun!
Glenn
 
HAHA Glenn living in Hawaii since the 50s I learned to swim, surf, dive, no problem. I feel like I'm at the kiddy pool now.
 
  • Like
Reactions: Z2V
You must log in or register to reply here.
Back
Top