Hi, I was wondering what methods people use for mechanical prototyping? Construction 'toys' like Lego, Meccano and K'Nex look like good options. Which do you prefer and why? What other options are there? Are there any good software-based solutions?
Thanks in advance,
I use cardboard, bits of plastic from drinks bottles etc, wood, anything that I can find around the house really. Plastic bottle tops make decent wheels and washers.
I personally just "bodge" things together, since I haven't got an interest in going from "prototype" to "production", yet - my "prototypes" are the "finished model".
What other options are there?
Well, there is fischertechnik - an expensive option, certainly.
Other things to look into:
Gridbeam (you could scale it down):
MicroRAX (small t-slot):
Are there any good software-based solutions?
There probably are, but they probably aren't cheap (or easy/quick to learn). For instance, software like 3DStudo Max, Blender, and others could be used to create 3D models and such, but to build a complex virtual working example will be a lot of effort (heck, just creating a simple model isn't easy). Google Sketchup might be an option. Then there are expensive (and not so expensive - even free open source if you know where to look) CAD/CAM packages (AutoCAD and others on the top-end, of course). I would also imagine there are complete prototyping on-screen "lego like" packages out there, but I can't imagine them being too inexpensive...
I would also imagine there are complete prototyping on-screen "lego like" packages out there, but I can't imagine them being too inexpensive...
If you want a bit of lego fun, take a look at BlockCAD:
Mowcius
I used to love fischertechnic! We had a load in my last year of primary school.
We had a load in my last year of primary school.
Well, consider yourself a lucky SOB; that stuff makes Lego look inexpensive - of course, given its capabilities for prototyping and design, its no wonder.
I like Plasticard, Rigid Styrene card, varying thicknesses, easy to glue with poly cement, easy to cut & drill, the fact i sell it doesn't bias my view it's good stuff, with regards servo's, legs and chassis i have sometimes used copper clad board of the epoxy variety and mounted control electronics directly onto the legs, chassis and such.
There's also balsa, coroplast, foamcore...
Add some bondo and/or fiberglass, etc...
Then there's polymorph/shapelock plastic (melts in very hot water; when cooled, it has the consistancy of nylon - easy to machine and work with, too).
For me the mechanical end of project is the easiest since I have a well equipped shop that includes all the power tools I could ever ask for (including a small lathe and milling machine).
Luckily over the past few months my employer has been cleaning out the storage bins in preparation for moving from two building into just one so the pickings of various chunks and extrusions of aluminum and polycarbonate off cuts has been great. I have even scored a vaccuum pump and about a dozen small pneumatic cylinders and valves.
Having said that since I have a well equipped shop, I have always preferred working in aluminum, plastic sheet (e.g. 1/8" or 1/4" polycarbonate), balsa or bass wood.
I have also found that my local surplus store has some great small project boxes for $2-10 each (some are plastic clam shells and others are plastic boxes with a metal faceplate).
And over the years, I have repurposed the usual Altoids tins, gum containers, metal cookie tins, etc. for various projects.
I have to say that having access to a laser cutter rather taints my choice of project enclosures. I normally think of how I can do it with a laser cutter so most of mine are laser cut something or other...
Nobody give me a 3D printer ;D Only kidding, please give me one! 
Mowcius
Then there's polymorph
Yeah thats cool stuff
over the years, I have repurposed the usual Altoids tins, gum containers, metal cookie tins, etc
Electronics and metal containers always make me nervous
Thanks for all the pointers - there is so much cool stuff out there that I didn't know about. Oddly I'd not thought of just sticking stuff together with cheap materials / stuff around the house - I was thinking quite specificially of something re-usable.
So, some plastic tubes, wooden poles, metal rods, bolts, jar lids, blu-tac, rubber bands and glue should do me for now I reckon!
I think I'll pick up a set of gears, they're cheaper than I thought they would be. I've got an old scanner I can rip to bits somewhere too - and I'm now thinking about getting some really cheap toys to rip to bits and use.
Awesome!
Thanks,