Calling out to all Fusion 360 masters!

[kludge]

So, I started modelling keycaps for the Commodore 64 just for shits and giggles, and I succeeded so well with the general shape of the keys that I thought that I'd finish. My problem is that I can't seem to generate the indentation on the top of the keys. I tried sweeping, but that just errors out saying that it would intersect itself. I tried lofting the top of the keys to a single point 1 mm below the surface, and while that did work, the profile is not right - especially for the wider keys.

I would ask on the Fusion 360 message boards, but I'm afraid they'll just tell me to use the "blahrgle blargh" and I'll feel stupid for not knowing what the f*ck they're saying

FYI my plan is to put the design on gitlab under some sort of open license if I get it right.

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[rubber_jonnie]

This may or may not work, but I used to use it a lot in TrueSpace many moons ago.

Make an object with a surface that matches the indentation, but it the negative of it. Then use that object as a tool and have it cut the face where the objects intersect.

Hope that makes sense....

[kludge]

Make an object with a surface that matches the indentation, but it the negative of it. Then use that object as a tool and have it cut the face where the objects intersect.

Yeah, I had the thought myself, but I didn't get much further. On the spacebar the top is convex instead of concave, so I would probably have to figure it out anyway. I'll have to google some more, that's for sure

[rubber_jonnie]

Make an object with a surface that matches the indentation, but it the negative of it. Then use that object as a tool and have it cut the face where the objects intersect.

Yeah, I had the thought myself, but I didn't get much further. On the spacebar the top is convex instead of concave, so I would probably have to figure it out anyway. I'll have to google some more, that's for sure

Basically it's just object subtraction, but I always found it easier to make a tool than manipulate a surface. I used it on my 2.5" laptop hard drive sled to get lightening holes, and on the floppy standoffs to get the holes and slots.

About to upgrade my laptop to 32GB/1TB HDD so I want to get into F360 again, give it a bit more welly

If I recall, and I might be wrong, you can make tools and then use them like a virtual CNC in F360, that may be a way for you to do it.

[tzok]

There is no single best way to do it, but I'd construct an offset plane above the top face of the key, and create a sphere in the center of that plane, and then, use it to cut the top face of a key.

[kludge]

Basically it's just object subtraction, but I always found it easier to make a tool than manipulate a surface. I used it on my 2.5" laptop hard drive sled to get lightening holes, and on the floppy standoffs to get the holes and slots.

About to upgrade my laptop to 32GB/1TB HDD so I want to get into F360 again, give it a bit more welly

If I recall, and I might be wrong, you can make tools and then use them like a virtual CNC in F360, that may be a way for you to do it.

There is no single best way to do it, but I'd construct an offset plane above the top face of the key, and create a sphere in the center of that plane, and then, use it to cut the top face of a key.

Thanks for your suggestions! I tried creating a sphere above the surface to remove material, but it didn't work. Or... It worked, but not in the way I wanted. The sphere didn't mesh well with the roundrect shape of the top surface.

I played around a bit with lofting to a point below the surface again, and it worked quite well for the normal keys with the square base. So I tried splitting a square key and move the two pieces apart, then "extruding them together" (for lack of a better term ). It worked quite nicely! I will probably tweak the radius of the loft, but the shapes are already quite close.

The spacebar is going to need a bit of work as well, but it's also coming along.

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[rubber_jonnie]

Looking good

Hopefully I can get some more time with my own copy of F360 soon!

[kludge]

Looking good

Hopefully I can get some more time with my own copy of F360 soon!

Thanks!

It’s a really great application. I’ve been designing simple stuff with it for a few years, with a break while my 3D printer was out of order (it still is, but I bought another one ).

[WDB]

How are you going to do the key labels? Do you have a laser engraver?

[Aeberbach]

I have done this recently to make a CRT monitor - I have been making a thing to fit in a Mac SE/30 case. It's the reverse of the curvature, concave, but same thing.

Start with your block of material and define a curve that is the correct curvature across one axis. This would be a side-on view of the key where you are drawing a new sketch with a curve that dips down toward the key. It does not matter at this point the distance from the curve to the key, only that the curve is correct. You can parameterise the distance from the centre of the the curve to make adjustments easier later. Once that curve is done finish that sketch.

Next you make a construction plane that is perpendicular to that curve. You should see the plane appear with the line of the curve going through the middle of it.

On the new construction plane you will make a tool. Start by making a rectangle that will be wider than the side of the key. Then bisect that rectangle with another curve, where that curve dips down to the centre of the key just like the first curve. The rectangle is divided by the curve.

Next you sweep the convex portion of the rectangle as a tool over the key along the path that you defined first... that cuts away a spherical cut! Move it up or down to control the depth of the cut.