First Time Bot Builder/Buyer

[RogueTwoRobots]

This is a rough price breakdown for my bot - its a 4WD invertible (I hope!) rammer so quite similar to what youre after:

Motors - 4 x 9.6V cordless drill motors - £40
Batteries - 4 x 7.2V Nicad packs - £20
Wheels - 4 x 75mm blue wheels - £22 (Although Id strongly recommend using 100mm blue wheels if you wanna be invertible - I managed it with the 75mm ones but vertical space is tight! Main bot chassis is only 50mm high!)
Speedos - 2 x Electronize 30A with external relays - £100 (15A microprocessor Electronizes are a cheaper option but only by about a tenner each)
Radio gear - 6ch Skysport - £120 (Technobots 4ch kit would be better though, and only £40)

Then theres the things you forget about at first:

Battery chargers for nicads - 2 x fastcharge units - £40
Miscellaneous nuts/bolts/screws etc - Could well possibly be up to £30 depending on how much you use.

So, going by the cheaper options Ive listed, youre looking at £255 give or take a bit, not including materials for chassis etc or any form of weapon. Thats the cheaper end of the scale anyway......

EDIT: Forgot about things like a removeable link, power light, failsafes, mixer etc - approx £35-£40 on top of that

(Message edited by K_C_R on April 25, 2007)

[geeza]

Jamie, if you are going to spend £120 on radio gear. You may as well get a Spektrum for an extra £30, we have 2 they are brill. Unless its too late.

[RogueTwoRobots]

Spektrums werent around in 2003 unfortunately

£120 was one of the cheaper quotes I got for the full kit; receiver, tx and rx nicads, charger and servos etc (one greedy model shop were trying to flog it for £170 - no wonder they went out of business)
It was also before the 6EXA came out, back when the Skysport 6 was the main product, hence why it still cost a lot

[woody]

ABS Roller from car boot £2 = 4 off 100mm dia wheels
3/8 UNF Deep Manifold Brass Nuts from your local motor factor another £2.

So for under a £5 you could get four wheels thatll fit on drill gearboxes.

As good quality wheels that arent likely to break? Questionable.

[woody]

Questionable.
Yes ...Ive not yet tested mine ...but to me they look O.K. .

http://shop.bodybuildingforyou.com/Images/ASOT/ab-slider.jpghttp://shop.bodybuildingforyou.com/I.../ab-slider.jpg

[xtreme]

so would that gimson kit do me with 4 wheels instead of 2 and 4 motors instead of 2 then? would that speed controller in the kit handle the 4 motors?

then i would need radio gear, batteries, chassis, fixing (bolts,screws etc),then armor.

what else?

[ewan]

I would suggest that to handle four drills the Sabertooth controller should be mounted securely to an aluminum block or extrusion or similar for additional heat sinking and a fan directed upon the board (you could run a small fan from your main battery or receiver power). Also avoid stalls. But up to 14.4v that should be fine even for four drills.

I have used one un-heatsunk unit with two 9.6v drills at 18v (100mm wheels) for around five minutes without any problems beyond a hot controller. Its just a case of taking all the precautions you can.

[xtreme]

how many 7.2V NICAD (2300mAh) batteries would i need to power the 4 motors or should i go with drill batteries instead of the rc car packs? drill batteries are like half the price too

(Message edited by xtreme on April 26, 2007)

[ewan]

This looks like an excellent option http://cgi.ebay.co.uk/Radio-Control-Battery-Pack-12V-3700mAh-SC-NiMH-Compact_W0QQitemZ300103587339QQihZ020QQcategoryZ34 063QQssPageNameZWDVWQQrdZ1QQcmdZViewItemhttp://cgi.ebay.co.uk/Radio-Control-...MH-Compact_W0Q QitemZ300103587339QQihZ020QQcategoryZ34063QQssPage NameZWDVWQQrdZ1QQcmdZViewItem

And remember youll need a charger suitable for whatever pack(s) you choose