Home made face grooving tool ...

[wquiles]

I buy my "D" size heatsinks for the P7 since it is not worth making my own. However, I have been curious for some time about making a home-made tool to do the "tower" part, like shown here:

So I started making a cutter out of 1/2" W-1 rod:

But when I tried there was a lot of chatter and it it broke fairly easily:

Since this is a good learning experience and I want to learn more about cutting my own tools and doing the proper relief angles, I keep working on it some more, and I then made two more out of thinner, 1/4" W1 rod:

These over-hanged too much, and had lots of chatter as well:

and one of them broke:

Since I am stubborn, I tried something more "radical", and also stiffer, so I did the next one out of 1" W-1 rod:

This one is starting to look more robust:

So I then grinded the relief angles:

and after heat treating it, I gave it a try:

It worked MUCH better, and had absolutely ZERO chatter - very stiff setup. In fact I was able to do a facing cut with it. I did some cutting, went back to the grinder 2-3 more times, each time the tool had less rub and cut cleaner:

I still need to make another one, play some more with the relief angles (getting a little bit of rubbing), but it has been a good learning experience so far

Will

 

[romteb]

The best finish i had on aluminum is with home ground hss blanks, not to mention that you can give them any shape your work require, that they last forever and can be resharpened till the end of times, and that you can give them such a nice sharp edge that you can take incredibly clean shallow cuts.

All you need is a HSS blank,a grinder, and 2 to 10 minutes of handheld grinding (i never cared too much about exact relief and other angles a 2° difference won't make much difference, just make sure your tool doesn't rub)

 

[precisionworks]

Well done :thumbsup:

You'll find when working with W1 that the depth of hardness (aka as case) varies directly with the amount of time the part is held at red heat. If the part is brought to red & immediately quenched in water, the surface is hard but the subsurface is still soft - tools made that way will "tell you" by bending when stressed.

For cutting tools, be sure to bring the part to red & hold it at red for at least 60 seconds (less for very thin parts, more for thicker parts). You may have to reduce the torch setting to avoid overheating (i.e. a yellow color). 60 seconds seems like an eternity, but is necessary for the transition phase (phase changes from ferrite to austenite) to penetrate all the way through the material. When quenched, this tool will have full through hardness & will not bend. But it will also be brittle & will need to be drawn back from full hardness.

A set of Rockwell hardness files comes in really handy, especially when trying to draw the hardness to a lower level.

http://www.amazon.com/dp/B001CTI7TE/?tag=cpf0b6-20

 

[bluwolf]

Will,

Very cool! Sometimes it's good to be a newbie. Then all the hard work gets done and figured out before I even think of doing something like that.

Is that the 6 jaw from your lathe, or a different one? And what is that on a magnetic base on the right side of your mill table? I thought it was a light but there didn't seem to be a lot of light on that side of the cutter.

And Barry, I've never heat treated anything. Thanks for primer on it.

Mike

 

[wquiles]

The best finish i had on aluminum is with home ground hss blanks, not to mention that you can give them any shape your work require, that they last forever and can be resharpened till the end of times, and that you can give them such a nice sharp edge that you can take incredibly clean shallow cuts.

All you need is a HSS blank,a grinder, and 2 to 10 minutes of handheld grinding (i never cared too much about exact relief and other angles a 2° difference won't make much difference, just make sure your tool doesn't rub)

Thanks. This was an effort over the last 3 weeks or so to learn more about doing my own cutting tools - nothing like "hands on" experience. I think I have some HSS tool bits somewhere in my "shop" - something new to try.

For cutting tools, be sure to bring the part to red & hold it at red for at least 60 seconds (less for very thin parts, more for thicker parts). You may have to reduce the torch setting to avoid overheating (i.e. a yellow color). 60 seconds seems like an eternity, but is necessary for the transition phase (phase changes from ferrite to austenite) to penetrate all the way through the material. When quenched, this tool will have full through hardness & will not bend. But it will also be brittle & will need to be drawn back from full hardness.

That I did not know. I think I only waited 5-10 seconds - I will wait more next time - thanks much :thumbsup:

Is that the 6 jaw from your lathe, or a different one?

It is also a 6", also a 6-jaw, and also a set-tru Chuck, but that one is a Buck Chuck, arguably an even better chuck than the Bison. According to Barry it was worth around $1500 new (another Ebay purchase for me):
New to me Yuasa RT and Adjust-tru Buck Chuck ...

I still prefer the Bison on the lathe since it has a larger ID than the Buck Chuck - perfect for swallowing a "D" size Mag

And what is that on a magnetic base on the right side of your mill table? I thought it was a light but there didn't seem to be a lot of light on that side of the cutter.

That is a Cedarberg protection shield, in the 9" size. I love it and should had bought one much, much earlier:
MSC Link ...


Will

 

[precisionworks]

I've never heat treated anything.

If any steel has enough carbon content, heat treatment is possible. The lowest generally accepted carbon level is 25 points, so a "normal" structural steel like 1018 (with 18 carbon points, or .18 %) cannot be heat treated. Some people like to say that heating it will not help it & will not hurt it.

A steel like Stressproof 1144 responds well to red heat & oil quench, as the 44 carbon points provide enough ferrite for conversion to austentite. High carbon steels (aka tool steels) usually have 100 carbon points or more, like W1.

For a brief explanation of heat treatment, go to: http://www.easterntoolsteel.com/data/hea_treatment_of_toolsteels.htm

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Better watch out, Will, Kaiser Tool will file for theft of patent

 

[precisionworks]

FWIW, here's a typical (straight) carbide grooving insert. Because carbide is a very stiff material, grooving inserts often have lots of front rake. HSS needs more metal directly under the cutting edge, meaning less front rake.

 

[wquiles]

Better watch out, Will, Kaiser Tool will file for theft of patent

I don't think they need to "fear" this newbie machinist is going to take business away from them

If that were the case, I would also have to "fear" Sanvik and others that have a similar, curved blade design:
Link ...


As soon as I finished the "curved" version of the tool last night a (very) small light bulb went ON in my head and I came up with a way to very easily do the relief cuts on the outer sides of the curved extension while still on the lathe, prior to milling, which will make for an even nicer cutting tool. That will be one of the "new" experiments for the next week or two

Will

 

[wquiles]

FWIW, here's a typical (straight) carbide grooving insert. Because carbide is a very stiff material, grooving inserts often have lots of front rake. HSS needs more metal directly under the cutting edge, meaning less front rake.

Doing the top and front rake are very easy on the grinder, for this particular application. The problem I am having is that since I need to go about 0.5" deep into the face of the heatsink, I have a lot of hangover, and chatter (which leaves a poor finish) - that is why the curved shape works better since there is more metal supporting the cutting edge, and of course the same reason Sanvik, Kaiser Tool, and others have adopted this "shape".

The tradeoff is that the curved shape can only "fit" in certain diameter range before it starts rubbing (specially on the ID part). If you then start cutting metal away to give you better clearance and more "room", then you are back to having too little metal supporting the cutting edge.

I found that if I make the cut in various shallower passes, I created clearance for the next cut, which then eliminates most/all of the rubbing. Still lots more to learn, but this simple project has tough me a lot of small things. I actually felt great, like I "got it", the first time the curved blade touched the surface of the Al block and I heard no chatter and produced a really nice curl - that was awesome!

 

[Tekno_Cowboy]

This is exactly the kind of thing I was trying to figure out a while back. I pretty much gave up and went to a 2-part adjustable heatsink for my mag mods. (handy for adjusting to varried LED's and getting emitters in focus)

 

[wquiles]

This is exactly the kind of thing I was trying to figure out a while back. I pretty much gave up and went to a 2-part adjustable heatsink for my mag mods. (handy for adjusting to varried LED's and getting emitters in focus)

I have been thinking about doing this for a while now, but it was the content in your thread that got me thinking about different ideas to try - so it is really your fault I have spent all of this time on just this one tool

 

[Tekno_Cowboy]

:lolsign:

You might be able to cut both inside and outside relief on the lathe, with creative use of a boring bar.

 

[bluwolf]

That is a Cedarberg protection shield, in the 9" size. I love it and should had bought one much, much earlier:
MSC Link ...

Will

Ahhh, now I see it. Thanks. I was making a mess fooling around on the mill, trying out the new 2" face mill that Barry pointed out on ebay, that uses the the CNMG inserts (I'm no expert but it sure cuts nice) earlier and thought, I really need to get something like that. Then a couple of curtains on the sides of the mill and I'll be able to keep the mess within a reasonable area.

If any steel has enough carbon content, heat treatment is possible. The lowest generally accepted carbon level is 25 points, so a "normal" structural steel like 1018 (with 18 carbon points, or .18 %) cannot be heat treated. Some people like to say that heating it will not help it & will not hurt it.

A steel like Stressproof 1144 responds well to red heat & oil quench, as the 44 carbon points provide enough ferrite for conversion to austentite. High carbon steels (aka tool steels) usually have 100 carbon points or more, like W1.

For a brief explanation of heat treatment, go to: http://www.easterntoolsteel.com/data/hea_treatment_of_toolsteels.htm

I just never stop learning here even when I'm not trying. Thanks Barry, I can use all the help I can get.

Mike

 

[wquiles]

:lolsign:

You might be able to cut both inside and outside relief on the lathe, with creative use of a boring bar.

For the outside I will use one of my round carbide bits, but for the inside, using a boring bar is precisely how I intend to give it relief angle for the next version. I will take a "few" photos

 

[Tekno_Cowboy]

For the outside I will use one of my round carbide bits, but for the inside, using a boring bar is precisely how I intend to give it relief angle for the next version. I will take a "few" photos

Oops! I meant just the inside for the boring bar. It wouldn't make much sense on the outside...