CAM Tool lengths? Flute vs Shoulder vs Body vs Overall

[Anonymous]

Anyone help me on understanding End Mill length definitions?

I'm typing in the numbers for a 1/4" (Dia.) Double Flute Straight Bit and I'm struggling to understand the defintions.

Flute Length - I assume this is the cutting blade, which in my case is 1"

Shoulder Length - I assume this is the gap between the tool holder and the cutting surface. I tried entering 1/8" but it will only take a value of 1" or the OK button greys out. The entire shank/shaft is a 2.5" length with a .25" diameter.

Body Length: I assume this is the cutter plus the exposed shaft (or shoulder length). I entered 1.125 (1" for the cutter, 1/8" for the exposed shaft)

Overall Length - I assume this is the entire piece. I entered 2.5"

Can anyone tell me what I'm doing wrong? When I select Shoulder length it is highlighting the flute.

[RandyKopf]

@Anonymous

So the confusion is over the fact that there can be more than one tool profile used in CAM. In a simple sense you could have a straight shank tool and the shoulder length doesnt mean much

But Fusion CAM allows different shapes of shanks though the tip size may be the same...

EXAMPLE 1

So in the first picture the tool tip diameter is 1/8" and it has 1/" length of cut. And overall length of 1.5" There really is no shoulder.

EXAMPLE 2

In this next cutter example shown below the tool tip is still 1/8 dia" But the shank you hold on to the tool with is 1/4 dia". And the length of cut is only 1/8". But it has a shoulder of 5/8" that is how far the tool can reach as an 1/8" like cutting a slot without hitting the shank. The overall length in this tool is 3"

CONCLUSION

Fusion CAM allows you to model this with the various settings you are asking about. I hope this helps

🙂

[RandyKopf]

[Anonymous · Accepted solution]

This is shown in the online help.  Not sure why Fusion's dialogs don't match it though...

Here's the link where that came from: http://fusion360.autodesk.com/learning/learning.html?guid=GUIDA0197982-0082-45AF-B848-8D62CAF57C49

Dave

[Anonymous]

Thank You Dave & Randy!

The explanation and diagram helped!

I was wrongly assuming that Sholder Length referred to the start and end of the shoulder.

After looking at the Dave's picture and Randy's explanation I can see that shoulder length refers to the distance between the tip to where the shoulder would start if it had one. So in my case I'm going to enter 1" which is also my cutting flute length since my bit has no shoulder to worry about clearance issues.

Shoulder Length should be renamed: "Tip to Shoulder Length"

thanks for the help!

Stephen

[scottmoyse]

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@Anonymous wrote:

This is shown in the online help.  Not sure why Fusion's dialogs don't match it though...

Here's the link where that came from: http://fusion360.autodesk.com/learning/learning.html?guid=GUIDA0197982-0082-45AF-B848-8D62CAF57C49

Dave

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Yeah... the UI designers for the Fusion tool library stuffed up. The Inventor HSM & HSMWorks tool definition dialogs are a lot clearer. Its the best thing about the tool library on those products, and it's been left out in the new Tool library. @al.whatmough

[scottmoyse]

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@Anonymous wrote:

Shoulder Length should be renamed: "Tip to Shoulder Length"

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I don't agree.... If I asked you what your shoulder height is, you would know it's from the floor to your shoulders. I think the name is fine. The UI needs to be fixed... the order of the inputs don't match the orientation of the tool either, they are reversed...

[Anonymous]

Hi Scott,

Good to know that the stand alone CAM Tool Library in HSM Works has a better explanantion, because I agree with your assesment that the Fusion 360 definitions definitely need help!

On a roadway shoulder length would be the distance of road that has a proper shoulder (10' wide on Interstates)

On a haircut shoulder length would be the length of a person's hair to where it touches the shoulder.

On an end mill shoulder length is causing confusion!

I think asking a user to enter a "Shoulder Length" on a straight flute is causing confusion based on the sheer number of comments on New Tool greying out the OK button. Having a No Shoulder option would help. I'm sure there is a better term that could be used. What would you call it? Would "Maximum Tool Depth" or "Reach Length" be better?

thanks for your insights

[scottmoyse]

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@Anonymous wrote:

Hi Scott,

Good to know that the stand alone CAM Tool Library in HSM Works has a better explanantion, because I agree with your assesment that the Fusion 360 definitions definitely need help!

On a roadway shoulder length would be the distance of road that has a proper shoulder (10' wide on Interstates)

On a haircut shoulder length would be the length of a person's hair to where it touches the shoulder.

On an end mill shoulder length is causing confusion!

I think asking a user to enter a "Shoulder Length" on a straight flute is causing confusion based on the sheer number of comments on New Tool greying out the OK button. Having a No Shoulder option would help. I'm sure there is a better term that could be used. What would you call it? Would "Maximum Tool Depth" or "Reach Length" be better?

thanks for your insights

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Reach length isn't always true though. It's only true when machining up against a vertical wall. It doesn't really matter what it's called as long as it's clearly shown what it represents in the user interface, which currently it does not. No one seems all that interested in changing it either, since it's been discussed since this new tool library format was released.

[maker9876]

I'm also lost and confused using this tool.

Here is my second attempt to create a chamfer tool. 

One photo shows exactly how I've filled out the dialogs + the tool itself in silhouette against the screen.

The other photo shows the dimensions on a paper sketch.

It's not just the nomenclature I find confusion. But also the preview. In particular the "overall length" doesn't show on the screen? Just the body? What is body anyway if it's not related to "shank"? Is it something like Gwizard's "stick out distance"? 

Anyway are the numbers filled out correctly, given the sketch?

I really hate having to guess stuff in CAM because it can have real world consequences! 😉

[cj.abraham]

The shoulder length seems to be causing a lot of confusion. To be honest, the shoulder length field is best ignored, and should just be equal to the flute length. The shank modifier should be where users define the shape. 

For example, going of of the small reduced shank tool picture:

And the chamfer tool:

[maker9876]

Thanks for your very complete answer.

I've been through it slowly and I think I understand.

Still not sure about "body length". Is that the part of the "total length" that is sticking out beyond the holder and is therefore susceptible to flexing / deflection?

Thoughts:

- perhaps the way to resolve the terminological difficulties (and I'm an English speaker, imagine how it is for someone who isn't!), rather than create a very elaborate system of mouseover tooltips with multiple examples, would be to find a way to enter the numbers and have them appear on the diagram itself? Then there could be no confusion.

- experienced users of software such as this know what are the essential numbers that have to be tended to; someone who is inexperienced must worry about and labour over every single dialog box which makes the experience overwhelming. Generally throughout CAM it might be good to find a way to highlight the numbers that MUST be filled out to avoid malfunction, and those which are refinements or options?

- somewhat unrelatedly, from the tool selector of a Toolpath, if I type "6mm" (no space) in the search box I do not get the same results as if I type "6 mm" (space between number and units). With "no space" some of the results are missing.

[scottmoyse]

"rather than create a very elaborate system of mouseover tooltips with multiple examples, would be to find a way to enter the numbers and have them appear on the diagram itself? Then there could be no confusion."

Kind of, well, exactly like, the brilliant format of the tool definition dialog in HSMWorks and Inventor HSM then. The fusion 360 tool definition dialog layout is truly hideous, my teenage daughter would have done a better job. Honestly. Someone broke something that didn't need fixing when they created the user interface for the Fusion 360 tool definition dialog.



Regards
Scott Moyse
Manufacturing & CAM Technical Specialist
Autodesk Expert Elite

[RandyKopf]

So one thing we can all agree on is there is plenty of confusion.  What complicates matters is not all cutting tool suppliers use the same nomenclature.

What is additionally confusion is the need to handle a tool that starts at one diameter then gets larger. The reason tools change shape is for strength and reach. Why this is important is 1) you always want to cut with the portions of the tool appropriate to the cutters design AND that meets your programming needs. 2) It also means NOT hitting or rubbing or gouging with other parts of the tool.

So take Harvey Tool as an example I attached. A critical dimension is labeled "L3" and when you see it in the example it makes sense that you need to know what that value is so you don't  try to cut deeper than this. otherwise you will gouge your part with the larger diameter that is not designed to cut.

So Harvey Tool refers to that "L3" label as "Overall Reach" and that makes sense. IF everyone called this "L3" dimension the same thing and everyone understood it's importance the confusion would disappear. I only advocate clarity and I hope this helps 🙂

One other key thing to note. The Harvey Tool Example is excellent to show what is referred to Diameter vs Reach. And for maximum rigidity and best machining finish you should select the shortest tool that will cut your part. So lets say you have a part with some micro slots. The dimension is [0.018" wide slot by 0.150" deep] there are many tools in that example below that can work. 

But the one tool I would use is the 0.015" Diameter with the "L3" of 0.156". That tool has a 12x length to diameter ratio. It's not too bad. That tool will be the strongest and have the least flex. I've personally cut 30x diameter to length ratio and it requires much more tool path and a different strategy to get an accurate cut. So in all theses examples "Overall Reach" is actually a great name for this field as Harvey Tool elected to call it. Not saying Fusion has to do that. It just needs to have clarity so we know what we are doing and why 🙂

[maker9876]

I should probably agree with everyone!

In the meantime still stuck on a relatively banal point so will repeat the question in case anyone knows. 😉

"Still not sure about "body length". Is that the part of the "total length" that is sticking out beyond the holder and is therefore susceptible to flexing / deflection?"

In other words is it the measurement from the tip of the tool to the holder? Not so much a property of the tool as how one mounts it? Or is it something else?

[scottmoyse]

Regarding the question about Body length... Yes. It's the stick out (distance from tool tip to holder face). It's also the value that gets changed if you choose to detect tool length in the 3D toolpaths.

Regards
Scott Moyse
Manufacturing & CAM Technical Specialist
Autodesk Expert Elite

[maker9876]

Thanks.

It's fun trying to figure all this stuff out.  

[maker9876]

@Anonymous.abraham Trying to get my chamfer tool working today, discovered that if you update a tool that you have created it is NOT UPDATED IN THE TOOLPATH. And nor is there any warning. You must open the Toolpath and select the tool again from the Library or it will continue to work with a Ghost image of the old one.

[scottmoyse]

If you update the library version, it doesn't update the copy in your fusion document.

Regards
Scott Moyse
Manufacturing & CAM Technical Specialist
Autodesk Expert Elite

[cj.abraham]

@maker9876 Yes Scott is correct. Tool Libraries are independent and not linked to the fusion document tools. This is intended behavior, as linking library tools to the tools in the document files creates even more undesirable problems.

Tool Libraries are for pulling tools into a project. If you are using the same tool again or modifying a tool, make sure you select from the DOCUMENT tool list. This is not clear in the UI and we are working to make this more obvious.