3D printer build volume

Have you thought of a CNC 3D router instead (Material removed rather then added), I am about to build a rig that will handle 4' x 4' from soft materials like foam right through to non ferrous metal and includes acrylic and plexiglass

Sounds like you want Armour built in one piece, this would be a lot of filiment and a huge amount of printing time, is the armour for cosmetic (Costume) or for real ?

for the sizes your talking, the CNC may be a cheaper alternatlive

Peter with the same budget I think that the solution maybe better in some cases but the working area remain almost the same.

Then there is a problem. If you work removing material only the internal surface is milled then there are two options:

1. The piece, already empty should be replaced again on the working surface reflected to make the external surface
2. A 4 axes mill machine instead of 3 axes so the piece can be milled on both the internal and external surfaces.

First case

In the first case there is the problem of reflecting the piece half machined that should be placed perfectly in correspondence of the other side that needs experience especially with a solid work.

There is the further problem that the milling tools rarely will work with the total depth of the 3d printers: when a 3D printer can create a piece with max height (z-axix) for example of 200mm, this means that it is really possible to make a piece of this height.

In the normal usage (with normal tools) the mill machine instead can work with reduced depth and this can create a problem (about 10-20 mm max)

The last problem is in the design, that should be done with CAD and working to convert it in 3 or 4 axes G-Code is more complex (i.e. using Blender, Rhino, Solid Works or similar CAD).

Second case

First of all a 4 axes mill machine (that will be definitely the solution if the material removing strategy is choosen) is more expansive and more difficult to manage and interface. This solution will dramatically simplify the 3D design just for the more efficient and less problematic milling process.

What I suggest after these considerations is that for this kind of product the better solution will be the 3D printer, IMHO. You mention that there is a large amount of material consuming with the 3D printing technique. If I am not wrong, it is possible to make empty stuff with the 3D printers (e.g. a dome), just leaving few internal plastic supports to keep the structure intact while machining and removed at the end with a cutter. So probably this problem of material consuming does not exist or is enormously reduced.

Enrico

Making empty stuff, yes but think more a bucket rather than a dome, the dome will require serious support structures (Material) in order to span the open spaces and therefor alot of cleanup after print to remove all that material. Remember the 3D printer is still working on a flat surface and a peice of Chest Armour is not flat in any direction so it will need all that support material. the outter part being the best option IMO to be the top side so it will have the better finish. the required 3D modeling for eith a 3D printer or CNC would be the same, it is how you then process it to the milling or Printing maching stage thats the fun part

If the parts are made from flexable material then they can be milled / printed flat and later moulded around the target subject. Better still may be to use the CNC to make the mould (Does not require 4th axis) and then vacume or fiberglass the final peice on the mould ??

This is a special case though and it is rare that people need this size of printing normally (Unless there in the business of making such items) so for a one off it may be better and cheaper o farm out the actual printing to a company that has the required size printer

If all the above talk is about a one off project then it would be a very expensive armour, if it is about setting up a manufacturing facility then at the end of the day, making moulds and vacume forming or silone moulds or other options would be a better way to go

options

Making empty stuff, yes but think more a bucket rather than a dome, the dome will require serious support structures (Material) in order to span the open spaces and therefor alot of cleanup after print to remove all that material. Remember the 3D printer is still working on a flat surface and a peice of Chest Armour is not flat in any direction so it will need all that support material. the outter part being the best option IMO to be the top side so it will have the better finish. the required 3D modeling for eith a 3D printer or CNC would be the same, it is how you then process it to the milling or Printing maching stage thats the fun part

If the parts are made from flexable material then they can be milled / printed flat and later moulded around the target subject. Better still may be to use the CNC to make the mould (Does not require 4th axis) and then vacume or fiberglass the final peice on the mould ??

This is a special case though and it is rare that people need this size of printing normally (Unless there in the business of making such items) so for a one off it may be better and cheaper o farm out the actual printing to a company that has the required size printer

If all the above talk is about a one off project then it would be a very expensive armour, if it is about setting up a manufacturing facility then at the end of the day, making moulds and vacume forming or silone moulds or other options would be a better way to go

options

This is a special case though and it is rare that people need this size of printing normally (Unless there in the business of making such items) so for a one off it may be better and cheaper o farm out the actual printing to a company that has the required size printer.

Correct, but as I have read this as a question in the forum, frankly I didn't think even a moment that maybe a production question. Sure in this case things totally changes. Also the solution of the carbon fibers with hot temperature molded on a sort of template and low pressure are a good solution. But I saw this kind of application just in aeronautical projects where money is the last of the problems (and this problem is ignored at all)

Completly agree

I dont think this will be solved cheaply with a home build or echonomically, other aproaches like outsourcing will be far cheaper in the long run I think, especially based on the probable materials involved and the Size.

Peter, there is also another fact I think.

But the stability of a full chest piece broken into 8-20 smaller pieces would drive me crazy! I'd love to build it as one piece

Thinking to the specific kind of objects, I expect that an armor is lightweight and robust, also if it is for playing or gaming. So, despite the problem to split in 20 pieces the original object (!!!) the use of the plastic condition two possible alternatives:

1. Make the armor (an entire piece) weak and usable with not too much weight
2. Make the armor almost robust (I mean about 5 mm thick) heavy and difficult to wear

The alternative with the mill machine at least solve the problem as a wider number of different materials can be used, including Aluminium that is relatively lightweight also with thickness of 1mm.

The better solution IMO remain the carbon fiber or glass fiber or similar not milled nor 3D printed but molded on a template (maybe also wood, there are lot of products that works with pressure only at cold temperatures).

Enrico

Exactly my thought, then the real issue is only getting the mould made and for that the CNC would be the better option (between 3D printing or CNC that is). A body mould could also be made directly from the subjects body and then used to form the fiber parts