This is a cluster body for a chandelier that I’m making…
My current plan is to… two side machine the part and hope that my bit gets enough contact with the bottom side of one of the holes that I can later rest my drill bit on what I know is “good hole” to steer the rest of my drill bit in? (good hole is reflected by the stripes in the simulation below)
I’ve linked the fusion file. Other ideas assuming that doesn’t work?
https://a360.co/37yO2Hc
If you got a 3d printer you could print another slightly larger dome to slip over the machined one and use as drill guide.
Interesting, that should be the next community challenge 
Maybe make two of those chandeliers. Carve two of those half-spheres, temporarily
glue them up to get a full sphere, then mill a jig with half-sphere-shaped pocket, and figure out how to index the ball at the various angles required, to drill one hole at a time vertically (on the CNC or drill press). But the 3D-printed jig sounds much more efficient !
My inclination would be to sacrifice a larger/thicker block of material and a large sheet of material thick enough to use for fixtures and would machine a series of rotated hemispheres projecting from a cylindrical portion with an ever increasing number of indentations which line up with the holes which the previous operations had machined, then face off the excess material in a final operation.
This turned out extremely well. First time I’ve been able to get an “orange peel” like finish on a part.
Now, time to hit up the friends with 3D printers.
Do the holes have to be radially perpendicular to the core? I know that is the simplest concept, given straight rods forming the structure of the light, but it also presents the most difficult (in 2.5D world) CNC challenge. The theory behind this is no more complex than: if a solution doesn’t exist, try changing something even if that seems initially illogical.
My philosophy is not to limit my designs by the reach of my tooling. Beside, the inspiration fixture is aprox $9000; so if I have to throw $100 to a friend to print a 3D part or $200 to fix a broken 3D Printer I have sitting in my basement I’m all for it.
Have you considered building a jig to hold the half sphere at angles to drill the holes using a drill press. For example CNC a smaller half sphere that fits inside current piece and mount the new part to triangular/wedge shape blocks to drill using a drill press. Would need 2 separate wedges for both series of holes at the 2 required angles and rotate final part on the jig to get multiple holes done (pattern).
3D print was $28 locally and done today. Will explore that option if the print isn’t successful
Actually instead of a sphere just cutting a pocket in the shape of a circle matching the outer diameter would probably hold much better. Then mount this piece to the angled block. In any case looks like an interesting project.
Very nicely done!
it’s “All your base are belong to us”.
The fact that I would notice this, and feel an irrepressible need to mention it, is a sad sad reflection of what a nerd I am 
Looks excellent, glad the 3d printed idea worked. Look forward to seeing the finished.
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