Earthwormjim's Stuff

[joey_picus]

if you're not having fun doing robots, you're doing it wrong (also did you change the text in your signature from black to red or have I gone mad?)

[earthwormjim]

if you're not having fun doing robots, you're doing it wrong (also did you change the text in your signature from black to red or have I gone mad?)

I might have!

[earthwormjim]

Chassis and disc parts ordered today from shapeways.
Disc has been designed to take 2 x exacto #19 wood chisel knife blades,
and SHOULD weigh in at around 45g, with the blades.

[mathias]

Rory is right, there are many easy to use and readily available tried and tested grippy tyre and wheel combos out there.
I like to experiment.Sometimes it works, sometimes it doesn't! I have fun trying out different ideas though!

There are, and that's why I ask so I can find other sources. Here in the US, the 150g weight class isn't as popular, so there's less products to choose from. I'm unsure about 3D printing wheels, so I'm always on the lookout for parts sources in case I decide to build a 150g bot.

[earthwormjim]

Hey, mathias.
If you are going to use the gear motors that most of us use in our antweights, then pololou do quite a few options. The most popular are the 32 x 7 mm wheels listed here. As they are reasonably large, it is advisable to use the slower gear motors (50:1) with them.

https://www.pololu.com/category/89/polo ... and-tracks

Hope that helps??

[Shakey]

*shameless plug*

I do extremely grippy silicone wheels that while 3D printed are done in thick abs to give them good spinner resistance (Used to be PLA but they were too brittle). I designed them for my own team to give me extra push but now sell them to others to fund more robot craziness, the link in my signature will show you them.

[joey_picus]

I use Scalextric sport wheels (example here) which handily grub screw directly onto 3mm shafts, although they're a little bit heavy. I'm always trying out different things too - I tend to have about five or six different types of wheels in my bits box at any one time! The trick really imo is to protect the wheels from spinners as much as you can rather than leave them exposed and rely on the wheel itself surviving; a big enough impact is going to break the gearbox or shaft bearing so you can be dear even if the wheel holds up

Will the knife blades hold up in impacts? I have enough trouble with them chipping even in daily use...

[earthwormjim]

Will the knife blades hold up in impacts? I have enough trouble with them chipping even in daily use...

Hopefully! (only about 3mm of the blade will be exposed, and I might cut the tips off too.)

[BeligerAnt]

Jim, I found that even the heavy duty utility knife blades shattered when used in a spinner. I just annealed them with a small blowtorch and although the edge doesn't last long at least they don't break. They also go a pretty range of colours

[earthwormjim]

Hi Gary.
Will give that a go for sure, thanks.