Beginner tool bit grinding Fixture

[SouthernChap]

To be fair, for lathe tools, a protractor, a Sharpie, a scribe and a reasonably sturdy rest platen should be all that's necessary for us home 'gamers', the vast majority of the time.

Still, nice learning project. Mr Pete knows how to teach and that's what this is, a teaching project.

For endmills and the like, Harold Hall has a pretty good design.

 

[cooper1203]

i have nothing against mr pete i think he is a great teacher that has been in the real world and then gone into teaching to share his exprience and now spends his own time continuing to teach. To be fair maybe i looked at the video with the wrong "mind set" when i saw the title i thought great here is something that i can make to help me grind tools rather than getting on my friends earhole and begging him to help me every time i needed a tool as to be honest i havent the foggiest and dont understand the profiles. I was disapointed that the way i see it some skill is still needed to use the tool

 

[ChazzC]

When you're first starting out, what is the bit supposed to look like?

LMS has a good solution to that issue:

They also have the set without the blanks, but for $6 why not get the kit?

 

[SouthernChap]

i have nothing against mr pete i think he is a great teacher that has been in the real world and then gone into teaching to share his exprience and now spends his own time continuing to teach. To be fair maybe i looked at the video with the wrong "mind set" when i saw the title i thought great here is something that i can make to help me grind tools rather than getting on my friends earhole and begging him to help me every time i needed a tool as to be honest i havent the foggiest and dont understand the profiles. I was disapointed that the way i see it some skill is still needed to use the tool

Blondihacks has a video all about grinding your own HSS tools. Honestly it's all pretty straightforward for lathe tooling. As i said above, a protractor, a sharpie and a decently sturdy tiltable rest on your grinder is all that's needed.

Also, if you can find one (and they're not hard to find or particularly expensive if you look on eBay), grab a copy of the South Bend book "How To Run A Lathe" or the Atlas Manual of Lathe Operations (AKA MOLO). Both do a great job of explaining the geometry of lathe tooling.

 

[CJ5Dave]

I built this jig for lathe tools that does the 30 degree and 5 degree angles. The sheet metal track has the relief angle built in. Yes I could grind them freehand, but with failling eyesight and only 2 hrs a day of concentration I need lots of mindless tools.
Wait, the jig is smart and I’m mindless.

 

[cooper1203]

Blondihacks has a video all about grinding your own HSS tools. Honestly it's all pretty straightforward for lathe tooling. As i said above, a protractor, a sharpie and a decently sturdy tiltable rest on your grinder is all that's needed.

Also, if you can find one (and they're not hard to find or particularly expensive if you look on eBay), grab a copy of the South Bend book "How To Run A Lathe" or the Atlas Manual of Lathe Operations (AKA MOLO). Both do a great job of explaining the geometry of lathe tooling.

i found this from the link chazz posted......
Grind the Front Relief

The first step in creating a tool bit is to grind the front relief. For most work, a relief angle of
10° works well.
While you are grinding the front relief, you are also creating the front cutting edge angle.
Make this angle about 10° also, so that the corner formed by the front cutting edge and the
side cutting edge is less than 90°

ignoring the fact that three paragraphs down there is a table with all the angles for each metal type and only one of them is 10 degrees front relief (copper) how is one supposed to grind three different angles at once

 

[GeneT45]

Here's a tutorial I wrote years ago, for another forum (now defunct). See if it helps.

 

[ChazzC]

i found this from the link chazz posted......
Grind the Front Relief
The first step in creating a tool bit is to grind the front relief. For most work, a relief angle of
10° works well.
While you are grinding the front relief, you are also creating the front cutting edge angle.
Make this angle about 10° also, so that the corner formed by the front cutting edge and the
side cutting edge is less than 90°

ignoring the fact that three paragraphs down there is a table with all the angles for each metal type and only one of them is 10 degrees front relief (copper) how is one supposed to grind three different angles at once

Yes, there are some discrepancies in LMS Grinding Tool Bits document, such as:


The best advice is given earlier that "For most work . . . 10° works well." Start with 10° all around and adjust to get better results with your material and equipment. Yes, you might end up with a lot of bits, but they are relatively inexpensive. An alternative is to use A.R. Warner T-15 HSS inserts:

https://www.arwarnerco.com/category-s/142.htm


Here's Quinn's take on the subject:

 

[WobblyHand]

If I recall correctly, there's a whole thread on grinding HSS tools, by mikey (RIP). Look in the beginner's forum, it's a sticky. It's an epic thread. To make things easier for you, try https://www.hobby-machinist.com/threads/models-for-grinding-hss-lathe-tools.62111/post-512368

It's where and how I learned to grind lathe tooling. I still have my copied lathe tool models that I made from key stock. Mikey's grinds and methodologies worked for me.

 

[SouthernChap]

i found this from the link chazz posted......
Grind the Front Relief

The first step in creating a tool bit is to grind the front relief. For most work, a relief angle of
10° works well.
While you are grinding the front relief, you are also creating the front cutting edge angle.
Make this angle about 10° also, so that the corner formed by the front cutting edge and the
side cutting edge is less than 90°

ignoring the fact that three paragraphs down there is a table with all the angles for each metal type and only one of them is 10 degrees front relief (copper) how is one supposed to grind three different angles at once

Just watch the BlondiHacks video mate.

You don't grind them all at the same time. You create the compound angles by grinding each angle and each grind affecting the previous adjacent grind.

Or just don't use HSS and buy carbide tooling. All the geometry is all done for you and you have to understand none of it.