Chassis Materials

[Eventorizon]

Hi there :-)

10mm Alu is a good starting point, as in most people totally underestimate the power of modern machines, and that might be a good option depending on the type of machine you want to build. There are many grades of aluminium so make sure you choose a good quality grade such as 6061 or 6082. There is also 7075 but its much more expensive, though much stiffer, so save that for when you do version 2.

The alternative is to use a wear steel like Hardox, about 3-4mm thick. Mild Steel is no good these days, but Stainless 314 is an option though very expensive. Calling up your local waterjet/plasma cutting company and having a chat and you should be able to source a sheet to suit your needs; K-Cut seems to be the go-too for many builders. Unless you have an angle grinder you won;t be able to cut or machine the Hardox yourself (unless you have the right tools) so most people have their base CNC'd from Hardox, with all the mounting holes for the other components done at the same time, and work from there.

[maddox10]

10mm Ali is thick and heavy for a feather and is about the same weight as a 3.2mm thick sheet of Hardox.

I would know what to use.

[Eventorizon]

Ignore the CAD. Even with 7+ years of working in solidworks, nothing I design is ever as the CAD says. I have taken to designing to roughly 5% under the limit. This seems to get me close once you include wiring lights, bolts, all the cable ties and electrical tape you use to lock things down. Even when the finished pieces weigh exactly what the CAD says they should somehow when its all together its always heavier than it should be.

Maddox is right BTW about the Alu and Hardox. However, if you feel better with Alu, go for that and then move to Hardox at a later stage.

[RogueTwoRobots]

Yeah if you're used to aluminium and can work with it, go for that. Hardox is great and all, but if you haven't got the right equipment to work with it, it can be a pain. And building a first robot will be a big enough pain as it is without adding more unnecessarily.

Whereabouts in Scotland are you based? I don't know many CNC or plasma cutter places up here but then it's not something I've really investigated much.

[R9000]

Yep, I made the mistake of having to tap Hardox - it's not easy to work with from my hours of trying to file bits down. Thankfully I know a guy who might be able to help, but if you're planning on metalworking without some serious tools, I'd go with Aluminium.