Materials and components for building amateur robots

I strongly recommend Gordon McComb's _Robot_Builder's_Sourcebook_ for robotics parts ideas. Really, this is only robotics book on my short indoor bookshelf. It sits next to the DigiKey, Mouser, and Jameco electronics catalogs.

For robot frames I use foamed PVC and HDPE. The foamed PVC can be purchased from Tap Plastics from the internet. It comes in 1/8" thickness and 1/4" thickness. It cuts and drills like butter. HDPE is basically cutting board plastic. It may be cheapist to simply buy a cutting board. I get mine from the scrap bins at Tap plastics. HDPE cuts and drill easily. I can also tap threads into it. I rarely use acrylic, but I do have a pile of it that I got from the Tap plastics scrap bin. Lastly, I use angle aluminum. I purchase mine from Metal Supermarkets, but Home Depot also sells the stuff.

I have a large collection of hardware screws, nuts, washers, etc. so I do not have to run off to the hardware store. These are carefully stored in 40 drawer organizers. When I buy hardware, it is always in units of 100 (or more.) I always hold everything together with screws. If I change my mind, I just unscrew, drill another hole somewhere else and try something different.

-Wayne

I used to keep a lot on hand but, seriously, I recently just gave 90% of it away. I spent good money for it over the last 20-30 years, never used the bulk of it, and it was just taking up space in my garage. I'm at a time in my life when I want to downsize rather than acquire, I guess.

Today I am very much in the "just in the time" mindframe. Of course I keep basic pieces of plastic and aluminum (same exact stuff as Wayne in his reply), and I have storage bins for hardware. I gravitate toward

4-40 hardware, which you can't get at most hardware stores, so I keep a variety of that in storage bins.

But I'm no longer a collector of junk and I tend to buy things when I need them. Most of my circuits these days are based on a microcontroller, so even my electronics bench is fairly bare because the circuits are much simpler. Gone are the boxes and boxes of caps, resistors, transistors, and other stuff. I have two 24-drawer bins for all my remaining electronics parts, and I don't use 98% of it. But, it's more convenient than going out each time if I need an LED or resistor.

What I like to do is plan ahead for my projects, order what I need from my favorite online resources (Spark Fun for the unusual stuff, Digikey for Sharp sensors, microcontrollers, and some others, a variety of catalog resources like Jameco or BG Micro for everything else), and then wait for the packages arrive. Honestly, it's more fun that way 'cuz it's like Christmas all over again!

-- Gordon

I suspect that what sort of materials people use is too individual for a general answer to be helpful.

My general rule of thumb is that whenever I need something I buy extra. So if I need one perfboard I buy two; if I need six screws I buy a box. That's built up a pretty good collection of just the things I need most over time.