Tool Grinding...How'd I Do?

Still confused... Help me here... Obviously, if you hit it with a torch, you're not holding it in your fingers. When you take it to a grinding wheel, I presume (but maybe I'm wrong) you still hold it by hand. Unless you got asbestos fingers, you can only hold the thing for so long before your brain figures-out "This thing is hot!".

If I'm touching-up a bit, it takes all of 5 seconds -no problem. If I'm making a bit from a blank, it needs a lot of grinding and will get too hot to hold (and I don't use gloves near a grinding wheel). So, I would have to grind until uncomfortably hot, let it cool, go at it again -yadda. Heck with that. Dunk it cold -really cold. Then, it takes a long time before it gets uncomfortable again and you get more grinding time.

Side note: My father could hold bits until his fingers literally smoked a little but I don't he noticed it. -Pretty sure he had asbestos fingers...

Anyhow, my Hanser book is at work (lunchtime reading of course) and I'll try to get the skinny on HSS annealing temps.



Tony Wells said:
I'll give you an extreme example. I wanted a 2.000 radius slab tool. I had a piece of 1" HSS. I took a oxy acetylene torch and burned it in according to a scribed line, then took it to a 10" 36 grit OA wheel to get it close to profile. Then I used another trick (to be given at some later date) to finish the radius with a smaller grinder. Never touched water with the tool. Never had a problem cutting 4140 @36 Rc.
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Ray C said:
If I'm touching-up a bit, it takes all of 5 seconds -no problem. If I'm making a bit from a blank, it needs a lot of grinding and will get too hot to hold (and I don't use gloves near a grinding wheel). So, I would have to grind until uncomfortably hot, let it cool, go at it again -yadda. Heck with that. Dunk it cold -really cold. Then, it takes a long time before it gets uncomfortable again and you get more grinding time.
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I can't help myself :o read the post directly above yours. Use or make some kind of tool to hold the piece you're grinding so as to protect your fingers.
 
Well, for one thing Ray, if it's getting that hot that fast, your wheel is too fine or hard....or both. But yes, a holding device is the key there. No need to stop and cool it anyway, so why do it? I have no feelings in most of my fingertips from all the nerve damage I have over the years, but I don't wait for the fingers to smoke (usually). I grab a pair of visegrips or a small vise or clamp of some sort. I have even tack welded a smaller piece to something to hold. About the only effort I exert to hold the temp down is power honing a fine edge.....mostly to keep the fluid properties intact while wet honing. And that is extremely rare. Most of my honing is done by hand and stays cool.
 
More stuff,if I can find it:

An 18th.C.style "mechanical" pencil. I need to get some 3mm leads for it. This thing has a bunch of parts in it. The handle is hollow enough to store extra leads. Basically,the rope knurled rings are slid up the tapered ends to clamp the leads. The leads can be retracted to protect them.

A tool steel die I made to coin a 22 kt. gold brooch and earrings for a retiring secretary who I had put to a lot of trouble ordering stuff for my shop!! I wanted to make her something nice,and wanted to have some fun at it. The ghost image pressed around the perimeter of the heart is from testing the die before it was hardened. Not being a press person,I didn't realize the press could squeeze silver hard enough to impress the 01 steel. Nothing hurt,though. I also made the 50 tom coining press I used to coin the gold jewelry. After coining,the heart brooch was "inflated" by pressing it face first into a hard urethane block about the hardness of a rubber shoe heel (80S),with a brass forming die behind it.

A late 18th.C. pistol. I made everything on it,even the springs and screws. This is the highest development of the flintlock before percussion was invented. It has roller bearings and a rain proof pan(none were REALLY rain proof!). The pineapple was the symbol of hospitality. This is a target pistol,not a dueler,because the barrel is rifled. Duelers had only smooth bores to increase the chances of missing the target. All the work on this gun was hand filed or chiseled out. Screws were turned on the lathe.

Note the 18th.C. style threads on the jaws of the hammer. I had to make a tap to match it. They are rather like tall,miniature light bulb(knuckle) threads. Also note the blued top jaw of the hammer. Some originals feature this blued top jaw on a polished lock. I don't know why.

IMG_0195.JPG IMG_0201.JPG IMG_0202.JPG IMG_0378.JPG IMG_0441.JPG IMG_0444.JPG IMG_0449.JPG Scan.jpeg View attachment 98812
 
Well, I'll be darned... Must have missed that day's class in Ph.D. school...:nuts:
 
Tony Wells said:
I'll give you an extreme example. I wanted a 2.000 radius slab tool. I had a piece of 1" HSS. I took a oxy acetylene torch and burned it in according to a scribed line, then took it to a 10" 36 grit OA wheel to get it close to profile. Then I used another trick (to be given at some later date) to finish the radius with a smaller grinder. Never touched water with the tool. Never had a problem cutting 4140 @36 Rc.
Click to expand...



Remember those days while running the big VTLs. Some of those HSS bits were huge, and had to be hand ground. They'd get all colors while grinding, and it didn't hurt their cutting ability a bit. Pun, intended!
 
Metalmann said:
Remember those days while running the big VTLs. Some of those HSS bits were huge, and had to be hand ground. They'd get all colors while grinding, and it didn't hurt their cutting ability a bit. Pun, intended!
Click to expand...

Yup, big old Bullard and a 1 1/4 or 1 1/2" HSS square. I've ground them with an angle grinder to get the angle I wanted. Never worried about color. Put them in a big bench vise and grind away. Burned them in two and ground perfectly usable tools out of the burned end. Never had a problem.
 
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