CAM for CNC code for cutting trispokedovetiles (3-spoke dovetailing tiles)

[Peter Dow]

Then image says Hexagon 100%

My method for specifying a particular shape of trispokedovetile is to specify the "CIRCLE" length as a percentage of the "HEXAGON" length, as illustrated in this diagram.

This image shows trispokedovetiles with CIRCLE = 130% - in other words the length of the diameter of the (partially drawn) circles is 1.3 times the maximal diameter of the (partially drawn) hexagons.

The parameters ask for a mm input????

Yes of course. My CAM webpage needs to know what actual sizes are intended to be cut to generate the correct CNC code.

So you type in what is the length in mm of the HEXAGON maximal diameter, what length will be equal to "100%"?

It's like if I tell you "the width of a rectangle is to be 100% and the length 130%".

Fine but before you can cut the rectangle from a sheet you need to know what length 100% is to be in mm.

[magicniner]

It's like if I tell you "the width of a rectangle is to be 100% and the length 130%".

Fine but before you can cut the rectangle from a sheet you need to know what length 100% is to be in mm.

Now you explain it it makes no sense at all.

What about needing a near zero tool diameter?

This code kind of works for a single tile,
================================================== ====
(CNC program to cut Trispokedovetiles by Peter Dow.)
(© Peter Dow. Caution - no warranty! Use at your discretion.)

(CIRCLE % = 118%)
(HEXAGON Length = 20 mm)
(Number of Rows = 1)
(Number of Tiles per row = 1)

(CNC Code BASIC)

G00 X6.34 Y90.00 (Fast traverse)
M22 (start cutting)
G4 P100 (dwell 100 milliseconds)
G01 X6.34 Y88.20 (Linear Feed Traverse)
G03 X16.56 Y94.10 I0.00 J11.80 (Arc interpolation)
G01 X15.00 Y95.00 (Linear Feed Traverse)
G01 X15.00 Y96.80 (Linear Feed Traverse)
G02 X25.22 Y90.90 I0.00 J-11.80 (Arc interpolation)
G01 X23.66 Y90.00 (Linear Feed Traverse)
G01 X22.10 Y90.90 (Linear Feed Traverse)
G03 X22.10 Y79.10 I10.22 J-5.90 (Arc interpolation)
G01 X23.66 Y80.00 (Linear Feed Traverse)
G01 X25.22 Y79.10 (Linear Feed Traverse)
G02 X15.00 Y73.20 I-10.22 J5.90 (Arc interpolation)
G01 X15.00 Y75.00 (Linear Feed Traverse)
G01 X16.56 Y75.90 (Linear Feed Traverse)
G03 X6.34 Y81.80 I-10.22 J-5.90 (Arc interpolation)
G01 X6.34 Y80.00 (Linear Feed Traverse)
G01 X4.78 Y79.10 (Linear Feed Traverse)
G02 X4.78 Y90.90 I10.22 J5.90 (Arc interpolation)
G01 X6.34 Y90.00 (Linear Feed Traverse)
M00 (Stop cutting)

G00 X0.00 Y100.00 (Fast traverse)
M30 (Program End)
=============================================

except that the inside corners will have the radius of the cutter so the square outside corners will not fit together with them.

EDIT- yes, probably good for a laser cutter which uses G-Code, but the paths will not work for rotary tool machines because square outside corners will not fit radius inside corners

[Peter Dow]

What about needing a near zero tool diameter?
...
except that the inside corners will have the radius of the cutter so the square outside corners will not fit together with them.

EDIT- yes, probably good for a laser cutter which uses G-Code, but the paths will not work for rotary tool machines because square outside corners will not fit radius inside corners

Does the package allow for rounding external corners to match the inevitable rounded internal corners?

What you see on that webpage is all that I have at the moment.

It is what it is and if that is of aid to someone in manufacturing some things in some ways but not other things in other ways then that's OK with me because I am not offering any warranty with the software.

[magicniner]

What you see on that webpage is all that I have at the moment.

It is what it is and if that is of aid to someone in manufacturing some things in some ways but not other things in other ways then that's OK with me because I am not offering any warranty with the software.

It should have gone in Laser Cutters, or possibly Plasma, as it's currently of no use to anything else.

If instead of a single flavour of G-Code with no consideration for the cutter being used it generated a drawing of a single tile there would be the option for using CAM to generate G-Code suitable for the user's machine rather than that suitable only for a laser/plasma which uses the generated flavour of G-Code.

It might make a nice decorative pattern for Diamond Drag Engraving the surface of a plate prior to cutting a part though.

[Neale]

I thought that this was quite an interesting design, so I looked at recreating it with Fusion 360:

I have attached the F360 model. I have used the F360 User Parameter feature to allow the user to tweak dimensions easily. Outer_circle_dia gives the diameter of the tile. Hex_spacing gives the centre-centre spacing of the hexagons that make up the underlying structure. Corner_rad gives the fillet radius on internal and matching external corners. Yes, I tried to fix the "sharp internal corner" problem.

Obviously, you can just go straight from design to gcode using F360 CAM and choose your own cutter diameters. You could, if you wanted, export a DXF version of the basic sketch. Note that because I was having serious problems in F360 in trying to draw one spoke and then use a circular pattern at sketch level, I actually extruded one spoke and then built up the tile using a circular pattern at the solid body level. This might make sense to someone with F360 experience, and if any of those people can point me at what was going wrong, please do so!
Threespokedovetile v7.zip

[magicniner]

Nice job Neale!

- Nick

[Peter Dow]

HOLES!
Now cut trispokedovetiles by CNC laser cutter with (or without) HOLES!

[Peter Dow]

I thought that this was quite an interesting design, so I looked at recreating it with Fusion 360:

I have attached the F360 model. I have used the F360 User Parameter feature to allow the user to tweak dimensions easily. Outer_circle_dia gives the diameter of the tile. Hex_spacing gives the centre-centre spacing of the hexagons that make up the underlying structure. Corner_rad gives the fillet radius on internal and matching external corners. Yes, I tried to fix the "sharp internal corner" problem.

Obviously, you can just go straight from design to gcode using F360 CAM and choose your own cutter diameters. You could, if you wanted, export a DXF version of the basic sketch. Note that because I was having serious problems in F360 in trying to draw one spoke and then use a circular pattern at sketch level, I actually extruded one spoke and then built up the tile using a circular pattern at the solid body level. This might make sense to someone with F360 experience, and if any of those people can point me at what was going wrong, please do so!
Threespokedovetile v7.zip

Thank you for your interest Neale.

I downloaded Fusion 360 to investigate your drawing but I didn't see any convenient way to get the full variety of trispokedovetile shapes, as is illustrated by the animation on my webpage, where CIRCLE varies from 100% to 150% of HEXAGON.

[Neale]

Thank you for your interest Neale.

I downloaded Fusion 360 to investigate your drawing but I didn't see any convenient way to get the full variety of trispokedovetile shapes, as is illustrated by the animation on my webpage, where CIRCLE varies from 100% to 150% of HEXAGON.

Peter - when I first looked at your drawing, I couldn't work out what you meant by circle and hexagon. I think that it was a bit like those optical illusions where you can see two different things depending on how you focus your eyes. Having now drawn it myself, I see it differently and I think I know what those value refer to, although I'm not sure whether HEXAGON refers to length of side of a hexagon or a hexagon's width between opposite faces, or half that value (radius of inscribed circle) - I think the latter. As a result, I think that I have chosen two different measures, although these are equivalent to yours in terms of changing these design proportions. The other point is that I have expressed both parameters as absolute dimensions rather than one dimension and a percentage of that one. However, you can still tweak either or both parameters to give a full range. It's also interesting to change the corner radius parameter as this changes the general appearance quite significantly.

EDIT - now had a look at the website. I had just been working from the embedded image in your post which was less clear at first sight. I see that HEXAGON refers to the hexagon's circumscribed circle. Make hex_spacing equal to outer_circle_dia in my drawing and you will get the same effect as circle=100% in yours; change hex_spacing for the range of shapes. Adding holes (making them hexagonal?) is clearly trivial in F360 so I shall leave this as an exercise for the reader, as my old maths textbook used to say. Assuming that I have any readers, which seems unlikely for anything as esoteric as this!

At the end of the day, though, this looked like an interesting vehicle to try out a couple of aspects of Fusion 360 that I had not had an excuse to play with before. I think it shows the power of a modern, parametric, CAD package to do things that were once the province of custom code - and it goes direct to gcode with full control of all cutting parameters as well. I'm a bit of an F360 fan but I don't want to take anything away from the originality of your initial design.