Artcam Help

[jeff_rowley]

Hi, I was wondering if anyone knew how I could use ArtCam to create half of a golf ball? It's easy enough to build the half sphere, but what is a good way to add the dimples? I can overlay some circles, but then they end up stretched down the sides of the sphere. Is there a way to 'wrap' the dimples around the half-sphere?

[jseiler]

Getting the cutting angle right on the dimples is going to be difficult without an indexer. One could use a ball end mill and some cleverness to attempt to meet the ball with the side of a ball end mill. I don't think artcam will take this into account angle of approach with their relief carving strategies.

If the dimples don't have to match exactly, one could carve a smooth round shape reasonably, then follow a circular path around the ball with a ball end mill, moving it inward every so often toward the centerline of the ball to apply the dimple. Once one created the lowest z circle curve, it could be moved upward and ofset inward to create the next layer of dimples. Once one moved up enough to not be carving on the sides, then the standard relief strategies could probably be used with a core box or ball end mill to do the topmost dimples. Lots of math. If one moved in too far to make the dimples, there'd be a good chance of breaking bits.

Wow, good luck (better you than me). Wear safety glasses and break out that long forgotten 3d geometry.

Speaking of indexers, anyone come up with a cheap way to implement a shopbot controlled indexers. I'd love to have one, but I can't really affort 1K for shopbots right now (hey, its the holidays).

regards,
John

[gene_marshall]

you have mail

[billp]

Jeff,
John is correct about getting the proper cutting angle. BUT a lot of that depends on just how MUCH of the golf ball you'd want to carve.
I recently did a small project where I had to scan a thimble on my Roland Picza. as you can see from the first attached picture it gave me very good detail on all of the "dimples"a standard thimble would have.
The second shot shows a rendering of how Artcam Pro handled that scanned file. As you can see it DID give pretty good detail 'around the curve'of the surface, but only to the point where the geometry of the bit on a 3 axis machine would make it impossible to carve. I do not have the original carved piece here any longer, but this is a very good rendering of what the job actually looked like.
So I think the question is; just how MUCH of the golf ball do you really need for the job in question?
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[jeff_rowley]

Wow! Thanks for everyone's help, especially Gene's. I was afraid this was going to be tougher than I originally thought, and I was right! It's advice (and assistance) like this that makes owning a Shopbot so much fun.

Is the indexer really down to $1K? The website was showing $2.5K and I was considering it, but at $1K I think I'd HAVE to do it... At least that's what I'd tell my wife.

[jeff_rowley]

Still messing around with the golf ball. Here's what I am working with for now. As you can see, and we have discussed, the dimples around the curve 'fade out'. What I'm trying to get a feel for is if this would even be do-able with the indexer. It seems like the indexer (and then cut it in half) would do fine around the middle (say tropic of cancer to tropic of capricorn), but getting the 'poles' would still pose a problem. Is it possible to cut this out with less than a 5 axis machine?

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[mmccue29]

Could you use a dramel will the round rasp and just touch them up?

[jhicks]

I would agree with the secondary finishing if you are doing it in HDU. I think a dremel is even a bit agresive. One could buff the dimples deeper or perpendicular to the sides in a few seconds with any domed surface and light sand paper.