Something Special

Ive been thinking about the drive for one of my featherweight projects and looking at motor possibilities. Im looking for something to give it high speed and decent torque for some full body hammer ramming. These are some of the motors ive thought about.

4 24v feathers- fine but nout special.
2 940 cobal astroflights without planetary- nice but would leave me with about £150-200 left for everything else and doubt thats enough.
thing gap motors- im not even going to think about them :sad:
24v dewalts.

anything else anyone can think of to give it some umph?

You could try the 18v dewalts at 24v with the team delta set-up. How much is your sponsor you mentioned before giving you?

Should be about £350 but its not technically sponsorhsip, its a grant for youth groups. I havent tried for sponsorship yet.

Reallistically i doubt i can afford many of the decent solutions but it might be nice to see if there are any possibilities

if you are looking to ram 2 24v golds can get you up to a very nice top speed or plenty of shove if you gear them right. Overvolting slightly (30v maybe) may be a good comprimise between the two.

4 12-14.4v drills at 18v should shift it although I dislike drills personaly had loads of trouble with them.

any advice on gearing golds? two stage pulley or spurs?

If your looking into pushing, use spurs or even chain/sprockets, or a combo depending on weight.

Mr Stu

I was thinking on using 4wd so chains would probably be easier i think. Would 4wd lower the speed if you only had two motors?

Options...

Motor = Price = Weight = Power ff6000>-1>12v/14.4v/18v Std. Drill Motors = -1>£9.99 £25.99 = -1>ranges = -1>ranges ff6000>-1>SS2 Gearbox/Motor Combo = -1>£86.34 = -1>1.02Kg = -1>1.43hp @24V ff6000>-1>Astroflight 940P Geared Motor = -1>£193.62 = -1>708g = -1>750 watts (1hp?) ff6000>-1>Dustin Motor = -1>£136.06 £167.46 = -1>1.53Kg = -1>0.98 @24v ff6000>-1>Team Whyachi T-Box -motor = -1>£99.42 = -1>816.5g = -1>Depends on motor ff6000>-1>18v Dewalt with Team Delta set-up = -1>£86.34 = -1>1.01Kg = -1>Not sure ff6000>-1>Ev Warriors = -1>Second hand = -1>1.47Kg = -1>1.55hp @24V ff6000>-1>NPC ThinGap motor/gearbox combos = -1>£206.70 = -1>938g = -1>About 0.5hp ff6000>-1>Technobots Feather Gold = -1>£24.95 = -1>870g = -1>150W @24v (0.20hp?)

Prices are from a current exchange rate and may vary.
Figures based on http://www.xe.com1USD

Alpha used a single stage gear reduction with 24v golds (at 24v). Other option maybe to use the 12v ones at 18v, stiff breeze uses overvolted 12vs and it performs very well. If you use golds i would suggest some form of cooling especially if overvolting. Have a look at the gold motor threads.

Chris just to say one thing, if i buy from the USA ill get about a £30 delivery cost

Yes I understand that. I just wanted to put out a quick/rough list of motors and prices. It might be useful to others if the information is correct. :s

Chris

Ok thanks chris. Any views on using ev warriors in featherweights and does anybody have any. How much did you obtain yours for chris?

Problem is with EVs is your looking at nearly 1.5kg each motor, you will then need a decent controller and batteries capable of taking the current.

Ok well looks like its golds for me. Hmm should i have four of them :).

not unless you found aload of ti hanging around. As your looking at the same weight then as EVs. One pair of Golds will be enough as long as you get the gearing correct.

Too much! The weight would be a bugger with them coming in at 1.4Kg so thats 2.8Kg for the motors then probably around 2Kg in batterys to supply them with power but then another large bump comes when these things start pulling amps as they can peak at about 198A so that means they would require a high power controller like a Vantec or Victor.

Another little side note for the Evs is that their timed to one direction so unless you are willing to re-time them, you will require one CCW and one CW. But because they are now getting harder to come by CW Evs are getting quite rare. I luckily have two CCW motors and one CW but there for another project.

Chris

If I may put my two pennies into this conversation...
If you are looking for serious drive for a feather take a quick look at... http://www.pillowtorque.com/tech.htmhttp://www.pillowtorque.com/tech.htm
The reason we setteled on the Astroflight gear motors was very simple....WEIGHT! (motor and gearbox bearly 700g with more torque than is reasonable!) against 860g +/- for a gold on its own, before you even think about gearing, wheels etc!
The whole drive system on Pillow Torque weighs just under 1.9Kg per side.. (Astros, motor mounts, pullies, belts, both wheels, axels & bearings!)

Theres one of things I wanted to ask you Geoff, were did you get Pillow torques bearings from?

NuTool Have come out with 36V drills at around 40 pounds each, we use the 30V ones with great results, but are now more expensive than the 36V ones as they dont make them anymore. You get 1.7Ah NiCads and a 1 hour fast charger along with the gearbox which is alot stronger than standard 18V ones.

Weve not used the 36V ones but the drill is the same size with just a slightly bigger battery pack. On litter Hitter each motor, gearbox, wheel and mounting setup is just under 1.5kg (I think, Graeme can you confirm?).

Using 2 motors and 80mm wheels is not quide as fast a pillow torque, but the setup is alot cheaper and you could always try bigger wheels.

Ceri, the bearings for pillow Torques wheels are simple 1/2 single row radial ball bearings from RS components. The internal nylon 6 bulkheads were drilled out to suit and the bearings were then pressed in.

What about:

Speed 900 BB Torque

or use the bonx system, as in a 2-speed gearbox, which gives me or 13 mph or 700 rpm

there just standard 2 speed geared drill motors

What about using a t-box with titan 550 motors or something similar? Or stock rc car motors?

SS2 Gearbox/Motor Combo = £86.34 = 1.02Kg = 1.43hp @24V

Thats not quite right. 4 x SS2s + 150mm Wheels + GP3300 24V pack = 1.62hp in the EDT software. Also 26km/hr top speed in a 12kg and 24kg robot. So a rammer pushing another robot WILL hit the same top speed as it would go if it wasnt pushing anything. And trust me on this. Our new Hellbringer has this exact setup and was pushing robots into the walls at over 20km/hr.

Yeh but four of them?

but your looking at 4.5kg for motors/gearboxes if you use 4. and what speedcontroller are you planning on using? as each motor can probably pull over 150 amps each (stall). Ats all well and good having this much power, but can you get enough traction?

i would recomend the IFI victors there small and could take any motor you stick in a feather

Never mind weight, look at price. I could use 2 and use a belt drive or similar to drive 2 wheels.

By the way does anybody do gearboxes for gold motors?

nope.

Ok well im gonna stick to golds in the mean time then upgrade later on. Is there anybody who custom builds gearboxes?
So gear reduction options are -
1. chain and sprockets
2. gearbox
3. belts

Which one would people recommend?

depends on the design of bot. for a 2 wheeled bot gears would probably be best. If you want 4-6 wheels then either use a system like storm 2 (geared to one set of wheels then chained off to others) or have one chain/belt that runs around everything. you dont have to have a gearbox to run gears.

Where can i get gears, chains etc.?

http://www.technobots.co.ukwww.technobots.co.uk

Mr Stu

Also.... http://www.hpcgears.comwww.hpcgears.com

and RS.

Sorry for hijacking a thread, but:
but your looking at 4.5kg for motors/gearboxes if you use 4. and what speedcontroller are you planning on using? as each motor can probably pull over 150 amps each (stall). Ats all well and good having this much power, but can you get enough traction?

IFI Victor 883s and lots of skid marks.
http://www.toowoombatanks.com.au/videos/highlights.wmvhttp://www.toowoombatanks.com.au/videos/highlights.wmv
Not a very good video, but you get the idea. (and of Philips flipper Marauder.)