Models for grinding HSS Lathe Tools

I think i will make a general purpose tool but out of the knife tool. I think that will be the most useful.
 
Another question is what should i cut for plastics like nylon and delrin?
 
For now, just use the aluminum tool. If very sharp, it will work well. Honing the tool makes a very big difference. We are talking slice your finger by just looking at it sharp. Ragged edges won't leave a nice finish.

The square tool is the most practical tool to grind first. It has lots of uses and is versatile.
 
@mikey @ttabbal i want to get a bench grinder but funds are maxed right now after buying this lathe i have a belt sander base but i need a motor to get that going. For making a tool with lower cutting forces should i just make the 15 degree tool? Is the 15 degrees on all sides?

There are some bench grinders on CL in your area. Not sure where Vernon is but here is a brand new Porter Cable for $35.00.

Of all the tools we have discussed in this thread, the square tool is the most versatile. Yes, tools with a geometry optimized for a specific material class will work better but you will have a hard time finding a tool that will cut almost anything as well as a square tool. That includes aluminum, delrin and other plastics, brass, stainless, mild and medium carbon steels. What's more, it was actually optimized for a little Sherline lathe so it will work on your lathe, too.

If I were you, I would go find a bench grinder. Then go to this thread; it tells you exactly how to grind a square tool.

Another option is to have @Z2V or @ttabbal grind a 3/16" tool for you to get you started. I have seen their work and it is as good as I can do.
 
This is another tool i found with the lathe.

top viewView attachment 355775
Left sideView attachment 355776
Right sideView attachment 355777
From the front viewView attachment 355778

@Gaffer i have that download and i have the cheat sheet for the angles but the 35 just doesnt look right when im trying to mark it out

I am now convinced that the guy who ground those tools had a different understanding of tool geometry than I do. Doesn't mean he is wrong but negative rake tooling on a very small lathe doesn't work well. Negative rake tools create nice finishes but also create huge cutting forces that require a lot of rigidity and power to utilize.

If I owned a little watchmaker's lathe, I would be using positive rake tooling and gravers.

If you do not have a solid understanding of the different tool angles, go here and read this stuff first:
 
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Im going to work on grinding one up tonight ill start with a square tool i guess. So when is a knife tool best used.
 
When the square one doesn't do the job! :D Believe me, the square tool is pretty versatile.
 
I don't use the knife much. It works, but I haven't found the right way to really get it to work as well as I think it should. I use various versions of the square tool for almost everything. The 15 degree is so versatile I can get a good finish on almost everything. I grind up special versions for a few things. Most steels work well, other than 1018, that stuff hates me. :)

I think the only small bits I have (<3/8) are harbor freight M2. I'll make you one if you need it. I have a set of model tools I can send as well.
 
I think i will be good @ttabbal i know the concept. Back to my original question i just wasnt sure how the 35 degrees was suppose to look or if i was measuring the angle right but now that i have seen the tool i know im measuring it right. I will make the square tool but i am making specialty tools as well bc im just that type of person. I like to challenge myself.
 
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