Adding dogbone fillet option to fillet tool

[bergdesign]

Would there be any chance of getting an option added to the fillet tool to generate dogbone fillets, or possibly a new tool just for dogbone fillets? I would be happy to help code one or to help specify the settings and options applicable to the various ways of generating dogbone fillets. I use PC and WT as my last step before transferring geometry to Enroute for CAM, and it really sucks to generate dogbone fillets manually

Thanks,
Brock Brandenberg

[huc]

Neat Idea...

Seems both WT and PCD Fillet tools are 'almost there' now. They need to respond to the mouse being located either INSIDE or OUTSIDE angle. Right now the tools only recognize INSIDE angle filets and there's zero visual feedback when dragging the mouse to an outside angle location.

Given a fillet is a fillet, I can picture it being either an optional setting to an existing tool, or simply being able to natively respond to the mouse location being inside or outside the specified angle. Seems an integrated approach, verses a new dedicated tool, would make more sense to users as opposed to the clutter of another tool in the palette.

Good luck with the project. I can certainly see where that type of tool could really speed the CAD/CAM drawing setup process

[Alfred Scott]

Please explain what you mean by dogbone fillet. Maybe a sketch?

Stupid in Richmond,

Alfred

And Brock, please send me an email with your contact info.

[bergdesign]

Hi Alfred.

I bet I'm just using a different name for this corner rounding method than you're used to seeing/hearing If you've ever routed an inside corner where two flat sheets of wood come together, like a mortise & tenon or tab & slot joinery, you've seen the need to remove the little "meniscus" of material in the corner where the sharp edge of the orthogonal piece interferes with the material left by the cylindrical cutter. In the furniture world, I see "dogbone fillet" used almost exclusively nowadays.

Here's a sketch of three different methods for cutting the corners of a slot, each of which allows the square edges of an orthogonal piece of material to slide into the slot without interference. The first one on the left of the hatched area is used most commonly, but the other two have their use in specific situations, the difference simply being where you put the curve relative to the two lines adjoining the corner.

Brock

[Alfred Scott]

It doesn’t make sense to me to add an option to the Fillet tool and over-complicating the interface and behavior.

The radius is always fixed so there is no need for an interactive mode, or using the Edit Window in the process of using the tool.

No need for inside-outside variants.

There is no need for a 3D or perspective variant of the tool.

This only makes sense when dealing with two lines or flat sides, excluding the line-circle, circle-circle and free form curves.

So I think we should have a Dogbone Fillet tool in the Special Curves tool palette.

We can have an option of a semicircle extension to the first line clicked on, so you would only have to know which segment to click on first.

I’ll put it on my list. Consider it done.

Alfred

[Charles Freeborn]

commonly used with CNC production of casework joints.

[bergdesign]

Alfred,

I think your choices and assumptions are spot-on.

* It doesn’t make sense to me to add an option to the Fillet tool and over-complicating the interface and behavior.
* The radius is always fixed so there is no need for an interactive mode, or using the Edit Window in the process of using the tool.
* No need for inside-outside variants.
* There is no need for a 3D or perspective variant of the tool.
* So I think we should have a Dogbone Fillet tool in the Special Curves tool palette.

I totally agree now on having a separate tool for it. As specialized of a purpose as this corner treatment is and because the dynamic and inside-out options of the normal fillet tool just don't apply to it, it does fit better as its own stand-alone tool.

* This only makes sense when dealing with two lines or flat sides, excluding the line-circle, circle-circle and free form curves.
* We can have an option of a semicircle extension to the first line clicked on, so you would only have to know which segment to click on first.

In thinking through your variants of line-to-line, line-to-curve, curve-to-curve and anything-to-anything, the line-to-line variant covers 99-1/2% of the cases where I would apply this corner treatment. And it will even be a right angle 99% of these cases due to the 2D nature of CNC milling which makes the edges of the panels perpendicular to the faces (unless you have a really expensive 5-axis machine). That perpendicularity dictates that the edges of the holes be at right angles to one another, except in a very few cases where you might make a joint where two panels come together at some odd angle, and you could just construct the corner geometry by hand in those very few cases.

I could see a single toggle for choosing the "arc through the corner point" variant or the "semicircle on the first side" variant, plus an input field for the cutter diameter. It could be radius, but when you're in the mode of making these kinds of corner fillets, the user will be thinking about bit diameters not bit radii. And an input field would be better than presets because the diameter will stay the same for every use of a particular CNC router bit, and there are a lot of bit diameters that could be used - 1/16", 1/8", 5mm, 1/4", 3/8", 1/2" to list a few - not to mention re-sharpened bits with slightly smaller diameters which would still require an input field to cover these cases.

Alfred, this will save CNC fabricators a ton of time

Thanks,
Brock

[Alfred Scott]

Brock,

Okay, this is what the tool's dialog looks like now.

While you can set the diameter to anything you like, I found that metric router bits are sized 2, 4, 6, 8...

Alfred

008.jpg (13.57 KiB) Viewed 9902 times

[Alfred Scott]

And the button dock looks like this, so you can change modes easily.

Alfred

008.jpg (5.65 KiB) Viewed 9886 times

[Alfred Scott]

The tool is now done and it will be in a future release.

The tool will trim lines to lines, but I ran out of energy dealing with trimming rectangles and polygons.

Alfred