Update

Managed to give a little bit of attention to Scar today for the first time since getting it. First job was to remove the inner box-section 'structure' that was there, presumably for the benefit of the old components that used to reside in it. Since it's getting a complete revamp in terms of its internals, they had to go. They were welded in so I predicted much use of angle grinding and swearing (it's quite tight!), but I quickly realised that the welds weren't that strong and was able to just bash each piece out with a hammer. Easy as pi and much more space now:

scar_build (7).jpg

I then started messing about with possible drive setups. The two motors I have to hand are a 300W scooter motor and a Bosch 400. After some deliberation, it's looking like the Bosch is the more viable option (unless I come across better options). The plan is to run it on a single-stage reduction, very similar to Tanto Jr/Scot-Bots housebot, although I'll maybe gear it for more torque and less speed. Might need to make some wheels from HDPE and cut/screw the go-kart tyres on though as they're currently not best set up to run on a shaft.

scar_build (8).jpg

If you click on the picture to enlarge, you may or may not be able to see the wheel shaft sticking through at the back, just below the welded nut. On each wheel, these are hollow and I'm assuming they just went over the wheelchair motor shaft and got pinned in place. But I'm planning on mounting a solid/fixed shaft on either side of the chassis, with wheels running on bearings. There's no scope within the current wheels to do this hence the possible need to cut and paste.

That's all I managed today, so now I need to source another Bosch 400. Used to have a second one as well - got them when they were going cheap on eBay - but sold it on a few years ago. D'oh!