Lathe hss bit grinding jig

I might add that after a tool is ground and used, that an observation of what really worked and how well it worked has to integrate the mind into the equation to fine tune the clearances that need to be applied to the facets of the tool. So far as the SB gage is concerned, remember that it works with the angles incorporated into the Armstrong type toolholders and would not be completely in tune with the Aloris type holders that most of us use, particularly in the case of front clearance.
 
MrPete did a Youtube video with a HSS tool grinding jig:


Craig
(I haven't made one of these. I just drew a couple lines on my grinder tool rest and tilted the rest to the other angle.)
 
I built a unit similar to the one shown in the MrPete video and one with a 90 degree combined angle face. Added the guide ledge he mentions and also built in the side angles so that I don't have to set the angle on the grinder. Have been happy with them. You will need a mill to build them tho.
 
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I appreciate all the input guys. I learned to grind tool bits years ago in gunsmith school. Now I know it wasn't near as intense as most of you machinist went through but I sure got tired of measuring the exact angles just to be told it wasn't quite good enough... and then over and over again....I do grind them by eye now but was hoping someone would suggest or have a picture of a simple fixture, jig,

How about it guys. I'll never be a master machinist just hoping for a simple jig.
Canus said:
I built the units shown in the MrPete video and have been happy with them. You will need a mill to build them tho.
Click to expand...
I do have a milling machine
 
Yah I need the 90 degree cutting bit fixture not 60 degree v thread one
 
I believe South Bend's "How to Run a Lathe" had an illustration of a jig that could be used on a bench grinder. Bear in mind that such a jig would most likely grind only one type of tool.
 
The last few bits I have ground I just left them in the tool holder.
Much easier to hold onto and follow the degree marks on the grinder tool rest.
Clamp a small piece/strip of flat stock to the tool rest to gage and guide the grind to the correct angles your grind calls for.
Gets you really close quickly.
 
finsruskw said:
The last few bits I have ground I just left them in the tool holder.
Much easier to hold onto and follow the degree marks on the grinder tool rest.
Clamp a small piece/strip of flat stock to the tool rest to gage and guide the grind to the correct angles your grind calls for.
Gets you really close quickly.
Click to expand...
Illinoyance said:
I believe South Bend's "How to Run a Lathe" had an illustration of a jig that could be used on a bench grinder. Bear in mind that such a jig would most likely grind only one type of tool.
Click to expand...
There is a company making a reproduction of the South Bend Jig. I have one and it works very well.
 
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