Wraith, the El Cheapo spinner

[knightrous]

I would just use an ESC! Conker 1 and Conker 2 both got their solid state relays jammed on at GSL 2012 and 2013. Despite both being capable of 30V & 100A and 50V & 80A respectively both failed repeatedly.

Did you have a flyback diode fitted across the SSR outputs? If not, it's very easy for a large voltage spike to cause them to jam on, I had a similar issue with MBX2, my Melty Brain FW.

[overkill]

Don't use a servo to trigger the microswitch, if the servo fails or jams, you cannot turn your weapon off (VERY DANGEROUS).
Use a battle switch or a modified ESC to trigger the relay, it's the only safe way.

Apart from the servo jamming, its quite possible for the relay contacts to weld closed. I had several spectacular automotive relay failures in my early bots and went up to a massively overrated relay that finally solved the problem. Using a TZ85a esc would make sense and its well overrated for that motor.

[Eventorizon]

Did you have a flyback diode fitted across the SSR outputs? If not, it's very easy for a large voltage spike to cause them to jam on, I had a similar issue with MBX2, my Melty Brain FW.

Yeah, I had the ones they supplied with the relays fitted. After it happened the second time I made sure I was doing it right, but it still kept happening. And at £30 a relay and going through 4 of them... might as well have got a beefy 1 way esc.

[mrsam]

Little bit of an update in the form of this lovely video which explains everything I couldn't be bothered to type, enjoy! http://vid921.photobucket.com/albums...ps318cf769.mp4

[Ellis]

(I suspect you meant this link: http://s921.photobucket.com/user/mrs...88b51.mp4.html)

Looks great man. Should be a very solid machine. Do you have a spec sheet for the 850 motor? 10,000@12v strikes me as quite slow compared to other motors in that size range.

[mrsam]

Yeah sorry I've changed it now, no spec sheet I'm just going on what Mario told me when I brought it from him.

[Ellis]

If he bought it from Pollin then it's very likely it's in fact 20,000 at no load. :P

[mrsam]

I'll stick a tacho on it when I test it properly, although something tells me the robot wouldn't like a 6000 rpm disc much :/

[harry hills]

I got a s900 with a angle grinder pinion on it somewhere. If you're after a slower motor that is.

[Flag Captured]

http://www.scorpionsystem.com/catalo...0/HK_7050_340/

There you go, motor problems solved.


I would try and have a look at the motor though, see how fast it ends up going. Maybe could get it all put together and then try it to see if it runs, if the motor struggles then replace it I suppose. The mechanism you've got seems great for the job, and if the motor still turns it, you can always limit the speed if needs be. I'm not so sure though without knowing the specifics... Brushless is always an option too I guess if needs be!