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Brento
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Here is one side
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- Dec 20, 2012
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That's a nice tool and it looks symmetrical. I assume it matches the notch in a fishtail gauge precisely, right? I suggest making the flat at the tip smaller, maybe 1/64" at most. You can also shift the point over to the left to get closer to a thread relief. Be sure to hone it carefully, including the top, and you should be good to go.
Good job, Brento!
Good job, Brento!
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Brento
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The other side of the tool im making a smaller cutter for that same reason and for smaller threads. The lighting wasnt the greatest where i was grinding but the sides matched up from what i could see looking by light
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What do you hone besides the cutting edge
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I just reground it to make sure it was 60 it was off just a degree maybe 2 and with doing that made the cutting radius smaller.
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- Dec 20, 2012
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Okay, looks better with the smaller flat at the nose.
I hone with diamond stones on both sides and the top. Be very careful to maintain your angles when honing; it is very easy to alter the angle. Just before you finish hone the top, do a light hone on the nose flat and then do the top. The tool should be very sharp and will cut clean threads if your angles are accurate.
Most threading tool charts do not specify the tool shape; it just includes the angles so I don't know what everyone else uses. What I found when using the chart angles on a threading tool is that there were a lot of burrs on the threads so the overall finish was poor. I found, after multiple trials, that a 15 degree relief angle on each side cut the cleanest threads and tool life is very good. My current threading tools are well over a decade old and are only honed occasionally but they cut clean, accurate threads with very little force. Very importantly, they do not deflect smaller diameter work pieces as much as a carbide tool so the threads are more accurate.
The key advantage to a inserted carbide threading tool, in my opinion, is that you don't have to grind them. Of course, you can also alter the helix angle on an inserted tool but that is only required on large diameters with coarse threads.
I hone with diamond stones on both sides and the top. Be very careful to maintain your angles when honing; it is very easy to alter the angle. Just before you finish hone the top, do a light hone on the nose flat and then do the top. The tool should be very sharp and will cut clean threads if your angles are accurate.
Most threading tool charts do not specify the tool shape; it just includes the angles so I don't know what everyone else uses. What I found when using the chart angles on a threading tool is that there were a lot of burrs on the threads so the overall finish was poor. I found, after multiple trials, that a 15 degree relief angle on each side cut the cleanest threads and tool life is very good. My current threading tools are well over a decade old and are only honed occasionally but they cut clean, accurate threads with very little force. Very importantly, they do not deflect smaller diameter work pieces as much as a carbide tool so the threads are more accurate.
The key advantage to a inserted carbide threading tool, in my opinion, is that you don't have to grind them. Of course, you can also alter the helix angle on an inserted tool but that is only required on large diameters with coarse threads.
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Brento
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Dan - I have no diamond files now its on my amazon wishlist but at the bottom but im going to take it to work and hone it on monday.
Mikey - im not sure what my relief angle is exactly but ill know more on monday. When honing you are really doing it to just break the edge of the sharp grinding burrs correct? Ive never honed before.
Mikey - im not sure what my relief angle is exactly but ill know more on monday. When honing you are really doing it to just break the edge of the sharp grinding burrs correct? Ive never honed before.
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- Aug 26, 2013
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You don't need diamond for HSS, cheap aluminum oxide or silicon carbide stones will work perfectly well assuming they are flat.
if you want some cheaper diamond cards, take a look at these. I used them exclusively for several years until i could afford something bigger/better. I still use them regularly as some times they are easier to manipulate than bigger stones.
https://www.sharpeningsupplies.com/DMT-Diamond-Card-Sized-Sharpener-P19.aspx