Building first FW - Drive system

[Team Crusader]

Just a quick update, I have decided to go for the pre-hacked drill motors from the robochallenge store. So right now I just need a speed controller. I am seriously considering the sabretooth 2x12.

For starters it has a mixer built in, so it saves me getting 2 separate speed controllers, and the voltages range input is around
6-24V. So it sounds suitable, given it would only cost me about £50, but if anyone has a more suitable suggestion at around a similar price then please do let me know.

Thank you guys for your input so far.

[Ellis]

Unless you have purchased them already, I'd try doing the drills yourself. It's simple. I made a how-to, you can watch that here: http://www.youtube.com/watch?v=OJMoh2C2Hdo

You'll learn a lot, and there is no way to make your next machine better than learning how the insides of your first robot work!

Also, and this is the main reason, RoboChallenge are very busy at the moment, doing TV work. There shop is probably not high on their priority list. I'll let them comment here if this isn't true but I don't think you'll be able to get the drills through them, or at least not quickly.

And considering how much you'll learn with nothing but a screwdriver and some grubscrews I'd say it's worth trying them yourself anyway!

Good luck either way.

Regarding speedos, two of these would cost the same: http://www.botbitz.com/index.php?rou...&product_id=74

I don't know how they do in combat as they're a fairly new product, but their larger cousin, the Botbitz 85a speed controllers, are gems. Cheap, solid, and quite good control. Whilst the Sabertooth will give you good control on two drills, it will never be far from its limits. If I were you I'd go for the 30a Botbitz, but if you can scrape up the cash now you'll save in the long run by getting tz85s. There are few if any featherweight drive systems that they can't handle, whereas the 12a Sabertooth is already struggling at the bottom end of two drills. Unless you get a dud ESC or wire them incorrectly or something the tz85s will last you multiple projects, the 12a Sabertooth most likely won't.

[Team Crusader]

Thank you for the video, I have already seen it before though, personally I would like to get them pre-hacked to save the hassle of getting the separate parts.

But if need be I'll hack them myself. Problem I found is that there is a site which sells the steel gears needed, but I'm not so sure about the number teeth the gears have, is it 15 or 18? The grub screws should be easy enough to find.

Thank you for the advice on the sabretooth, I think I will get those 30A ones since I don't want to be spending about £100 and blowing my budget on the 85A ones. or blowing £50 on a dud.

Thank you for the help, once I get these parts together I can begin to focus on the design.

[Porker]

There is only (apparently) one drill motor/ gearbox left in stock.

[Team Crusader]

Thank you all for your help. I have now decided on what I'm going to use. I've decided to just buy a cheap pair of drills and 30A speedo's from botbitz. Was a bit pricey but not as much as the 85A ones.

Once again thank you all for your help