Is it possible to....

[tauntingboar]

Hi all,
I would like to produce some of my own small scale busts / figures. Maximum size for a figure would be about 30cmx30cmx40cm, same for a bust.

Would a 4 axis cnc machine be able to create for me what I want?

Some examples

http://www.sci-fi.co.uk/graphics/large_obilogo.jpg
http://www.sci-fi.co.uk/graphics/dcjoker.jpg

I know this might sound a simple question to most but I cant decide if it will work or not?

If anyone has any other suggestions besides sculpting them please feel free to comment.

Regards

[guynamedbathgat]

Though you could probably make an approximation of these on a reductive type of machining center. these types of things are made from molds. If you simply want to reproduce the figures you've posted I would make a mold of them (there are lots of ways to do this) and go that route rather than sink a ton of money into something that has a lot of 3 dimensional limitations when it comes to clearances, undercuts, tool radius's, work holding and on and on.
If you want to make your own original figures, again these things are typically sculpted by hand then a mold is produced from that original to make multiples. That is really the best and easiest way.
If you really want to machine them using a 4 axis router or something like that, you are going to have a long very fun journey of trial and error and finally the realization of the limitations of these types of machines. Hope this helps.

[Phyrexii]

No, you would need a full 5 axis machine to cut those, because there are undercuts along multiple axis. Sorry...

[Seth Hensel]

A number of firms make molds for similar products using rapid prototyping technology. Commonly known as '3D printing', small machines can be had new starting at roughly $15,000 and used on E-Bay for a third of that or less.

By the time you are up and running with a 5 axis machine that can handle the dimensions you require, you may well have at least $5000.00 invested.

[Carroll Johnson]

Regarding reproducing small scale busts & sculptures: For less than all-out volume production your best bet is to make silicone rubber molds to hand cast the replicas. You will need to sculpt an original model if you can't buy or borrow the figure you want to duplicate. There are several suppliers of silicone rubber and casting urethanes in a wide range of hardnesses and other characteristics. Most suppliers have helpful information in their catalogs, some books, some videos on the subject. Do a search on the internet for artist & sculpture supplies. Two good sources are Polytek (Easton, PA) and Smooth-on. You could start with a model of the size you want, adding modeling clay to it to sculpt the unique features you want on the final model, making a mold of that and then casting an easy to work urethane (properties similar to wood), then refining the casting by carving methods (if needed), then making another mold from the refined casting, and so on. The softer silicone rubbers are tough and very stretchy to pull over undercuts, and reproduce the smallest details.

[Carroll Johnson]

Regarding reproducing small scale busts & sculptures: For less than all-out volume production your best bet is to make silicone rubber molds to hand cast the replicas. You will need to sculpt an original model if you can't buy or borrow the figure you want to duplicate. There are several suppliers of silicone rubber and casting urethanes in a wide range of hardnesses and other characteristics. Most suppliers have helpful information in their catalogs, some books, some videos on the subject. Do a search on the internet for artist & sculpture supplies. Two good sources are Polytek (Easton, PA) and Smooth-on. You could start with a model of the size you want, adding modeling clay to it to sculpt the unique features you want on the final model, making a mold of that and then casting an easy to work urethane (properties similar to wood), then refining the casting by carving methods (if needed), then making another mold from the refined casting, and so on. The softer silicone rubbers are tough and very stretchy allowing the molds to pull over undercuts without tearing, and faithfully reproduce the smallest details.

[techwoman57]

We have a 3-D printer that might work for your project. It takes in an STL file and builds the part in ABS plastic. For more info, go to www.jetpoint.com