building a drum spinner

[Max]

Re: building a drum spinner

i am conserned that those second hand batteries will be knackered so want to buy a new set. i came across these:
http://www.batterymasters.co.uk/Product ... _1916.aspx
would they be able to do both the drill motors for the drive and the speed 900s for the drum? I was not sure if they would be able to deliver the amount of current needed.
Thanks
Max

[jonny]

Re: building a drum spinner

i'd say shove in a lipo

[typhoon_driver]

Re: building a drum spinner

If a speed 900 is too expensive then lipos will be well out.

Those batteries will not be suitable. They are designed for standby applications where the current draw is minimal so they won't be able to supply the current. The second hand ones that Ed is selling are a good deal. Knowing Ed he will have only used the best chargers to charge and maintain them.

[Max]

Re: building a drum spinner

i will buy the 2nd hand nicds and i will buy speed 900s for the drum,
where can i get a v-belt pulley for the speed 900 and what type do i need?i will buy the battle swithch from robochalenge and the other relay as well.

[Max]

Re: building a drum spinner

Hi
could i use this as my second relay (in conjuntion with a robochalenge battleswitch) to control a speed 900 motor to power the spinning drum:
http://www.halfords.com/webapp/wcs/stor ... e=shopping
the 100A relay of jaycar looked way to expensive for a relay
and again, what gear ratio do i need between the speed 900 and the drum?
thanks

[Max]

Re: building a drum spinner

Hi, where do people get the pulleys and belts from?

[Laser]

Re: building a drum spinner

Technobots

[typhoon_driver]

Re: building a drum spinner

I use rs components for mine. Less than 2 quid for a replacement belt

[typhoon_driver]

Re: building a drum spinner

O and you can pick up dirt cheap relays on ebay. Do a search for 24v relay and look for one in the 30 to 40 amp range. Seen them for less than 2quid each

[jonny]

Re: building a drum spinner

You can also get relays for a quid each from a scrapyard

[typhoon_driver]

Re: building a drum spinner

Getting ones that can handle 24v from a scrappy might be tricky

[Max]

Re: building a drum spinner

Hi,
I've got most the parts for the robot apart from wire, connectors and relay which are on order from Jaycar electronics but have not arrived yet(even though I've been waiting for 20 days!)
I have bought the 12v sanyo nicad batteries but don't know what I need to charge them? I've got an overlander power rc 6s charger but It looks much smaller than the ones shown on this forum.
Also, I have calculated that I've got around 1.5kg for the drum and have figured out that if I use steel it will only be 1.5mm thick, will this be strong enough or should I make it out of aluminium?
Thanks,

[typhoon_driver]

Re: building a drum spinner

Lol they're coming from australia so it's not surprising on the time!

You need a charger that can charge nicads/nimh. As long as it can charge a 12V pack it should be fine as long as it can supply around 2A to the battery pack. Could you pop up a pic of your charger?

What diameter drum is that for? What style of teeth are you planning on using? (ring or bar)

[Max]

Re: building a drum spinner

The drum will be 75mm in diameter but 85mm including teeth, I plan to weld on a number of hooked teeth like the ones on a circular saw but much thicker and with only two teeth in a circle, it is quite hard to explain.

[typhoon_driver]

Re: building a drum spinner

Take a look at either boner or drumroll. Are the teeth a similar design? (Jamie has a few in his build thread)

I would recommend a drum material thickness of around 3mm. This is the same as both boner and drumroll and the drums have survived hits with some of the worst spinners in the arena.