Team MedBots

If you are keen have a read through http://www.robowars.org/forum/viewto...er=asc&start=0

Both escs flashed!
In case anyone else attempts the same I used the kkMulticopter flash tool which was incredibly easy to use, and the key to getting it working was using Zadig (http://zadig.akeo.ie/) to install the correct driver for the USBasp, and when installing the driver I had to select "libusb-win32 (v1.2.6.0)" as the driver. initially I chose the wrong driver and it would not work.
Another top tip that I only spotted after doing the first esc, there is no need to remove the heatsink, just leave it stuck on.

Ok, continuing the theme of nothings ever as easy as it seems:
I've gotta to switch out the broken motors on my Gimsons to new ones but the new ones I've got have the smaller gear on them. Anyone got any advice on switching the gears from one motor to the other? Should I rely on the interference fit or use superglue? Is there a better way than brute force to get the gear off/back on?

Got the gear off the broken motor by heating the gear up with a blow torch, but in the process all the oil/grease in the motor bearings boiled out and caught fire. So don't think it would be great idea to do that to my healthy motor to get it's pinion off. Anyone got any suggestions?

The textbook way is to use a gear puller.

http://www.hobbyking.com/hobbyking/s...talog/S630.jpg

The hobby ones for that size pinion generally suck but do work if you are careful. They are available at many R/C stores and Hobbyking. The one from HK looks better than most.

I have the HK one. Works fine for 1/8 shaft stuff. I have pulled a 5mm bore pinion with it but wouldn't recommend doing so often - it worked but the threads began to fold.

If I use these bearings for my drum are they likely to just explode on impact?
http://simplybearings.co.uk/shop/p15...duct_info.html

I would go for a self aligning double row bearing e.g.

http://bearingsdirect.com/22200-seri...-25x52x18.html

Wouldn't bother with the fancy bearings. The ones you linked should be fine and get the job done. Sure they may need replacing after an event or two but having a spare in the toolbox isn't going to break the bank.

It always seems to be the shaft that ends up going on drums or the drum itself rather than the bearings.

2 pneumatic questions:
1) Can a 3/2 valve be used 'backwards' so that a gas supply can be connected to one side then be switched to supply either one of two rams? (Obviously the gas wouldn't be dumped after an activation of either ram but this isn't a problem)
2) Does anyone know of an affordable 3/2 valve rated for full pressure (ie at least 1000psi)?
Thanks!

Depends on type of 3/2 valve. Normal low pressure valves can be used in reverse.

No, I don't know on any affordable, light 3/2 valves that can handle FP gas.

Hey,
Haven't had any progress in a long time as I've been really busy with Uni, but I'm going to try my best to make some progress on my featherweight drumbot to get it finished.

Had a question about the Red Brick ESCs, so a small per usual I'be made the robot a bit too small and there's not much space for all the electronics, just wondering if anything can be done about the big capacitor sticking out of the end of the red brick, has anyone attempted to remove it? Is it needed for our application, and if so has anyone tried to move it to somewhere else in the system?

Big capacitors between the battery leads are usually to prevent some kind of excessive change in current I believe, or to smooth input. The circuit might work without, but probably less reliably, or it might break more easily.

I've found myself with a bit of spare time so have gone and entered my drumbot into the DRG FACTS event, now I've just got the small matter of finishing the robot!

I'm trying to work out how to run power from the brushless to the drum, unfortunately I've left myself with no way of getting a 'closed' belt like a timing belt on there so need a belt that comes split and can be joined in-situ. The best option I've found is polyurethane round belts like these: https://www.ebay.co.uk/itm/Orange-Sm...8AAOSwkShY9oGn

But I'm not sure how many/what diameter to use, has anyone with experience with these belts got any suggestions? I was thinking maybe 3no. 5mm diameter belts?

Can't comment in the drum drive, but I've used split fan belts on cars before now, but only ever as a roadside repair, that said I don't see why they wouldn't work so long as you can tension it properly.

Is there no way you could remove the drum to fit a belt? Personally I'd feel better entering an arena with a one piece belt, but I'm and ardent over-engineerer(erer) ha