3D printer build volume

I guess You work on CAD? Am I wrong? 
I am  quite new as to printing 3d too but I know that the most important think is project so the most safety for you will be precisely check out all your work by someone better the you (I don't think that you are not good enough, but it's good to give our project to check one anyone else cause other person may notice something that escape your notice and if you ask about that it's obvious that better ask someone better than me)

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

Hi flysuit

I have no idea of what is the real size of the pieces you should machine, so I have no idea of how many parts should be expected. Also I'd like to know what is the CAD or anyway software you are using to make the design. Better if you can provide one piece example (stl format maybe good).

Then just a note about the difficult to make separate pieces. I think it can be solved simply as any good 3D cad has the functions to virtually cut the pieces of an object. The way I usually adopt in cases like this is following this simple proceure :

1. Make a cube with surface thickness 0 (if this kind of objects are not accepted use a 0.001 thick) of the exact size of the 3D printer working area (maybe better some mm less)
2. Replicate adiacent cubes on the X-Y (at the same Z = 0 level) to include the entire object that should be created
3. For every cube (corresponding to one 3D printing session) save a copy of the file (e.g. draw1, draw2, draw3 etc.)
4. Open the file draw1, remove all the cubes than the first
5. Select the cube and subtract the entire object. Depending on the CAD you are using maybe that it is the first object subtracted to the second or vice-versa, try the first way and the second and use the one that works for you.
6. Set the 3D object coordinates (xyz = 0,0,0) to the bottom-front-left corner of the cube
7. Remove the cube used to cut the object.
8. At this point you have the part number 1 of the object for the 3D printer. Export in the 3D printing format and proceed with the machining of the piece.
9. Repeat points 4-8 with all the remaining files.

At the end you should have all the components, perfectly cut without any calculation effort.

Let me know if something is not clear.

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

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

Wow! You guys are amazing! Thank you for the great responses.

Little background on the project:

I like to make costumes for fun, so they are generally a one off deal.

Enrico, i like your idea of creating a mold and using a carbon fiber or fiberglass piece. But i need to create the  Template or model.

I am toying with the idea of making one mold that I like and replicating for friends, however, the problem is... friends come in all shapes and sizes! So it will most likely be one off pieces.

I am working on creating different forms of armor. From Medieval Knights, to robots to Halo & Iron Man type costumes. I am working with Blender and exporting the stl files.

There were questions about  the size. I Imagine the biggest part would be the chest plates which could be as big as 24"x24"x12

Peter, you are right, printing a helmet, or chest piece would require a lot of support (extra material)... and it could get expensive. I saw a guy make a full size Ironman helmet, and used almost 3 kilos (rolls) of filament.Although i think he messed up in the settings of the supports.

I love the thought of a CNC machine, but the issue becomes the material costs. I'd need a 6"-8" thick piece of material to CNC. I dont really want to work with foam, although I have been experimenting with EVA foam.

Your also right that i could save a ton of money by outsourcing... but I feel part of the fun in life is creating new things, at every step of the process. While outsourcing would save me time and money, I wouldn't feel good about not building it.

Right now i'm still teaching myself how to chop everything up on blender. I should have a 3D printer in the next couple weeks. If I don't like it, i'll return it.

Probably going to build it in smaller pieces as I cant afford a large format 3D printer just yet.

I am very interested in building my own CNC machine as Peter pointed out. I'm sure I can find many uses for it on other projects!

Have any of you worked with 3D printers before? any major cautions?