Hi everyone, so what does a chap, who has very limited mechanical engineering experience, no tools more advanced than a battery drill and jigsaw, who last built an antweight over 10 years ago and who has been bitten by the bug again since watching the last series do? Build a featherweight crusher of course!

I started generating some ideas a couple of months back and in hindsight, I should have started this build thread back then so you could have all told me about the mistakes I no doubt have made. I decided that I wanted to make a FW crusher. Crushers have always been my favourite type of robot and having a good read of the forum it doesn’t seem like there has been too many of them built, and I think it should push the limits of what I am capable of. I decided to aim (for no particular reason) to try to get around 1 tonne at the tip of a vertical crusher, as this seems reasonable.

I set about finding a ram and means to power it that would give me the force needed at a sensible ratio at as light a weight as possible.I’ll put some details of that in a later post, but once I had the sizes of this, I could set about designing the chassis and the rest of the bot around it. I have never really used much CAD software, but I downloaded Fusion 360 and after a bit of messing around I was able to get the hang of it. After about amonth of design and re-design, I came up with something I was fairly happy with. Again, I’ll put some pictures up of the CAD in another post when I get on the other PC. The thing that became apparent very quickly was that it was going to be difficult to get something in the weight limit that doesn’t tear itself apart if it bites on something it can’t crush.

Fusion 360 has some simulation capabilities built it, so after watching the tutorials I set it to model the chassis sides with the expected loads the ram and crushing arm will put on them. I still don’t really have much idea what I’m doing, but at least I could see if each iteration of my design was better or worse than the previous one. It seemed to make something strong enough and within the weight limit, that I was going to have to use titanium for the chassis. I spent a lot of time refining the design and then I had a look at the availability and cost of the titanium. Wow. I know it is expensive but I had no idea just how bad it was and I should have checked this before putting too much time into the design. After another read of the Riobotz manual and some more research into materials, I have changed the chassis to 7075 T6 ali. Still not as cheap as I would like, but much more reasonable than the titanium. Anyway, a couple of weeks back the designs went to waterjet cutters and yesterday I picked up this:

IMG_20161116_185201374.jpg

That is one of the chassis sides and it has come in on weight budget, yay! Its on the dining table as the shed isn’t ready yet. I have some more bits of the bot that I need to take pictures of and add to this diary, but I think that’s enough for the first post, comment and critique welcome!

P.S. As per the thread title, I don’t have name for the bot yet, any ideas on that welcome too.