Re: [OpenSCAD] Rotate Spoke try 2
in 2D you might be looking for this, e.g. a 7-gon:
in 3D you get some results with
which are mostly not satisfying. If you want do something like a
dodecahedron, you'd calculate each corner point and face and define a
polyhedron, for which you can use the "new" vector stuff. I give an example
for a 2D hexagon:
But there are also other, more combinatoric methods for defining bodies.
E.g. a dodecahedron:
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Parkinbot wrote
in 2D you might be looking for this, e.g. a 7-gon:
in 3D you get some results with
Yeah I actually managed to get what I wanted with cylinder & $fa
But it doesn't do <5.
I'll have a look at the rest of that and see if i can figure anything out.
Will it work with cylinder?
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vIQleS wrote
I'll have a look at the rest of that and see if i can figure anything out.
Will it work with cylinder?
What a question. Why don't you just type it in and see what happens. (Of
course it will.)
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Parkinbot wrote
in 2D you might be looking for this, e.g. a 7-gon:
circle(100, $fn=7); <== *
- note that unfortunately using More/Raw-text gets dropped when it goes thru
the mailing list. Prob don't want to use that.
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OK - I figured the polygon thing out thanks to the clues. I've now learned
linear_extrude. Yay!
Now the last (hopefully) thing is the fudge factor.
I want to automatically rotate the 3D n-agon so that the corners line up
with the arms. The code below is right.
I haven't been able to figure out a ratio that works for every possible
n-agon. Is there?
--=code=--
NoArm=7; //how many 'spokes'
ArmWide=3; //width of each spoke
ArmHigh=3; //height of each spoke
ArmLong=80; //length of each spoke - from centre
fudge=5.56; //to align the indent. between 1 and 6. adjust until 'v' shows
up on each arm
Deep=1; //depth of indent
InsetRad=45; //radius of indent
Circ=0; //size of circle in middle. zero for no circle, Advised if hole or
slot
Hole=0; //size of hole in middle. zero for no hole.
SlotWide=0; //slot instead of hole. zero either to not slot. no slot if
circ>0
SlotDeep=2;
DGrees=360/NoArm;
//polygon cylinder stuff
p = [for (k=[0:NoArm-1]) let (angle=360/NoArm*k)
[cos(angle), sin(angle)]
];
difference()
{
union()
{
for (i=[0:NoArm-1])
{
//arm
rotate([0,0,DGrees*i])
translate([-ArmWide/2,0,0])
cube([ArmWide,ArmLong,ArmHigh]);
}
//circle in middle
if(Circ>0)
cylinder(ArmHigh-Deep,Circ,Circ);
}
//indent
rotate([0,0,NoArmfudge]) //THIS BIT
translate([0,0,ArmHigh-Deep])
linear_extrude(height = Deep+1+ArmHigh, center = false,
convexity = 10, twist = 0)
polygon(points = pInsetRad);
if(Hole>0) //hole in middle
{
translate([0,0,-ArmHigh])
cylinder(ArmHigh*2,Hole,Hole);
}
else if(SlotWide>0&&SlotDeep>0) //slot
{
cube([SlotWide,SlotDeep,ArmHigh*2],center=true);
}
}
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MichaelAtOz wrote
Parkinbot wrote
in 2D you might be looking for this, e.g. a 7-gon:
circle(100, $fn=7); <== *
- note that unfortunately using More/Raw-text gets dropped when it goes
thru the mailing list. Prob don't want to use that.
In this case I could have done it, because the code is a short liner. But
generally it is not a good idea, as you get line breaks (copy & paste will
not work) and also loose code alignment. So I prefer to follow the link at
the bottom of the mail.
By the way, I guess the prob is not new, so why has it not been addressed
(or even solved) til now?
- Rudolf
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vIQleS wrote
Now the last (hopefully) thing is the fudge factor.
I want to automatically rotate the 3D n-agon so that the corners line up
with the arms. The code below is right.
I haven't been able to figure out a ratio that works for every possible
n-agon. Is there?
forget about the factor. It's not a factor. It's an angle offset of 90°
between the two objects. So the affected code lines are:
Hint: difference() (and intersection()) sometimes obscures, what's really
happening. My trick is to temporarily comment is out to see, what's going
on.
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Nathan ?
Anyway if you add a # at front of the line you can see the shape. E.g. here:
linear_extrude(height = Deep+1+ArmHigh, center = false, convexity = 10,
twist = 0)
#polygon(points = p*InsetRad);
This trick will visually show you exactly what's not working right.
I empirically determined the values for noArm=3..9 and then had a stab at
the calc. Seems to work.
My mod below.
NoArm = 7; //how many 'spokes'
ArmWide = 3; //width of each spoke
ArmHigh = 3; //height of each spoke
ArmLong = 80; //length of each spoke - from centre
Deep = 1; //depth of indent
InsetRad = 45; //radius of indent
Circ = 0; //size of circle in middle. zero for no circle, Advised if
hole or slot
Hole = 0; //size of hole in middle. zero for no hole.
SlotWide = 0; //slot instead of hole. zero either to not slot. no slot if
circ>0
SlotDeep = 2; //
DGrees = 360/NoArm;
//polygon cylinder stuff
p = [for (k=[0:NoArm-1])
let (angle=360/NoArm*k)
[cos(angle), sin(angle)]
];
difference() {
union() {
for (i=[0:NoArm-1]) {
//arm
rotate([0,0,DGreesi])
translate([-ArmWide/2,0,0])
cube([ArmWide,ArmLong,ArmHigh]);
}
//circle in middle
if (Circ>0)
cylinder(ArmHigh-Deep,Circ,Circ);
}
//indent
//echo(NoArm=NoArm, 360/NoArm, [for (x=[3:9]) [for(i=[0:x]) 90-360/xi]]);
rotate([0,0,90-360/NoArm]) //empirical 3=-30,90, 4=0, 5=18, 6=30,-30,
7=-13,38.5, 8=0, 9=10
translate([0,0,ArmHigh-Deep])
linear_extrude(height = Deep+1+ArmHigh, center = false, convexity = 10,
twist = 0)
// #polygon(points = pInsetRad);
#circle(InsetRad, $fn=NoArm);
//hole in middle
if(Hole>0) {
translate([0,0,-ArmHigh])
cylinder(ArmHigh2,Hole,Hole);
} else {
if(SlotWide>0 && SlotDeep>0) {//slot
#cube([SlotWide,SlotDeep,ArmHigh*2],center=true);
}
}
}
--
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Sorry for side-tracking...
MichaelAtOz wrote
- note that unfortunately using More/Raw-text gets dropped when it goes
thru the mailing list. Prob don't want to use that.
Parkinbot wrote
In this case I could have done it, because the code is a short liner. But
generally it is not a good idea, as you get line breaks (copy & paste will
not work) and also loose code alignment. So I prefer to follow the link at
the bottom of the mail.
By the way, I guess the prob is not new, so why has it not been addressed
(or even solved) til now?
I've been looking thru Nabble to try to figure out what's going on.
I've now got to the code minus one step (which is a binary I have not, yet,
had access to the source)
I'm thinking that it is a security setting, as theoretically, you could put
malicious html which then gets placed in an email.
If the 'message is in HTML Format' is ticked, Raw works, but the plaintext
you type is then 'formatted' so you loose spacing etc.
I'm hoping to get some combo of the HTML format, but with it preserving
basic layout, but it is slow learning Nabble. Or alternatively an equivalent
of Raw, but say 'Code' which addresses it somehow.
"So I prefer to follow the link at the bottom of the mail"
As long as you realise that a majority of people here seem to rely on the
mailing list and will not see Raw. In case you don't see your own emailed
posts, this is what your post looked like:
in 2D you might be looking for this, e.g. a 7-gon:
in 3D you get some results with
which are mostly not satisfying. If you want do something like a
dodecahedron, you'd calculate each corner point and face and define a
polyhedron, for which you can use the "new" vector stuff. I give an example
for a 2D hexagon:
But there are also other, more combinatoric methods for defining bodies.
E.g. a dodecahedron:
I suggest marking code as,
/itallics, /
or inside
quotes, using the %lt quote %gt markup. But don't use the 'Quote' button -
it will replace your text with the prev. post.
It may depend on mailman setting tho. Unfortunately I don't have a test
mailman to play with. So the below is part of the test.
Y'all let me know of you don't get the two identical code bits in your mail,
(italics and then quoted), and I can check mailman settings.
/fudge=0; // this factor is dispensible
//polygon cylinder stuff
p = [for (k=[0:NoArm-1]) let (angle=360/NoArm*k + 90)
[cos(angle), sin(angle)]
]; /
fudge=0; // this factor is dispensible
//polygon cylinder stuff
p = [for (k=[0:NoArm-1]) let (angle=360/NoArm*k + 90)
[cos(angle), sin(angle)]
];
Newly minted Admin - PM me if you need anything, or if I've done something stupid...
Unless specifically shown otherwise above, my contribution is in the Public Domain; to the extent possible under law, I have waived all copyright and related or neighbouring rights to this work. Obviously inclusion of works of previous authors is not included in the above.
The TPP is no simple “trade agreement.” Fight it! http://www.ourfairdeal.org/ time is running out!
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OK, for my mailman settings, itallics was a flop, but the quote method
worked.
Changed my settings. Was MIME, now Plaintext. Retesting... (itallics, quote)
/fudge=0; // this factor is dispensible
//polygon cylinder stuff
p = [for (k=[0:NoArm-1]) let (angle=360/NoArm*k + 90)
[cos(angle), sin(angle)]
];/
fudge=0; // this factor is dispensible
//polygon cylinder stuff
p = [for (k=[0:NoArm-1]) let (angle=360/NoArm*k + 90)
[cos(angle), sin(angle)]
];
Newly minted Admin - PM me if you need anything, or if I've done something stupid...
Unless specifically shown otherwise above, my contribution is in the Public Domain; to the extent possible under law, I have waived all copyright and related or neighbouring rights to this work. Obviously inclusion of works of previous authors is not included in the above.
The TPP is no simple “trade agreement.” Fight it! http://www.ourfairdeal.org/ time is running out!
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