Ironbark works well, you can usually get 2" thick slabs of it for cheap too
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https://www.halfdonethings.com/

Working on a large transmission and at a point where I have to work out how to attach a drive motor.
JW if anyone could give some advise.

Am trying to mount a motor - 5mm output shaft to a 5mm protruding input shaft of the gearbox.
Was wondering if a small pulley and belt would work, only doubting because if the motor is a dewalt or something big and the belt is only a couple of inches long spinning at high rpms, dont know.

Is there any thing anyone can suggest is NQR about doing that.
Has anyone seen a belt drive straight off a dewalt anywhere?
If it would work what size belt would i be looking for.
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i think that should work okay. that brushless im using has a much higher rpm then a dewalt motor and ive never lost a belt so far. as long as there is ample tension on the belt it shouldnt run off ever, specially if the pulleys are flanged. even the crazy electric rc cars run huge long timing belts at rediculous rpm.

not sure how the belts would like the constant slamming backwards and fowards. probably would fare better then the gears in the drill gearboxes anyway.

15mm wide belt would be plenty for a drive. theres not that much difference between a 10mm and 15mm belt id just use the bigger one as a bit of insurance.

timing belts sound like a good idea over any other option though. direct linking them together would need to be pretty damn accurate to keep it from binding and what not.
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www.demon50s.com - Minimoto parts
http://www.youtube.com/user/HyzerGlen - Videoooozzz

A timing belt would be better than a grooved pulley in that situation IMHO. Depending on how the shafts can be aligned, a flexible coupling would be even better - virtually no speed limitation, no chance of coming apart and probably lighter. you can get them with a plastic coupling for a tiny bit of shock protection, or there are several zero backlash metal designs.

If you need a reduction as well as coupling, consider gears; they are almost always more compact than belts and chains and often lighter as well.

Thanks guys, should have taken a pic earlier but heres one anyway.

The thin shaft extending out the bottom is what I have to work with.
The little pic in the top right corner is the other top gear, not exactly the same but the gearing is and enough length to get them machined the same.

Those 2 gears off the side are just floating till I work out how to connect a motor. The bottom shaft will be flush with the gear.

http://www.robowars.org/forum/album_pic.php?pic_id=1520

A belt drive is sounding better, I already have a reduction of 16 to 1 so only a slight reduction would make a big difference.

edit- have had a look at RMP and realised that at a 5mm shaft size there is not much of a reduction possible unless i reduce the width of the belts, have to look into this more.
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Are any of the SSAB metals useful for robots other than Hardox? http://www.ssab.com/en/Products-and-solutions/

I am particularly wanting thinner material for the top of a robot and possibly the rear to save weight. Docol and Domex are available in thinner sizes. I have not asked SSAB Australia if it is available here.

Are any of the stainless grades comparable to Hardox?
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So even the rain that falls isn't actually going to fill our dams and our river systems

Have a chat with Steve Gleeson @ SSAB Brisbane. The last time I spoke to him he was really helpful with providing information.
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https://www.halfdonethings.com/

JW

Would like to look at moving over to A123 batteries this year.
Looking at RMP there is 3 different plugs you can have on the balancer.

What is the way people have gone.
Can anyone suggest what sort of charger I should be looking at.
Would like to purchase a few batteries to make a pack but dont know which choices to make.

Tritons and Nicads where simple -
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Bots that do not destroy you, only make you stronger.

Charger wise, I've been using the iCharger 1010B for a few years now and it's been a brilliant unit. Can charger 10cell @ 10amps no problems! If your not running big voltage packs, you could look at it's little brother, the iCharger 106B which is limited to 6 cells.

Balancer plugs wise, Trent used DB9/serial port plugs for his packs and had no issues, Glen (IIRC) has used hobbycity leads and Andrew has used PCB pin headers. I on the other hand dont run balancers plugs, I just do pre-event low amperage(500mah) charging which seems to work fine.
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nope me and welch use header plugs + leads from a type of car alarm

that shits me as well that there is no standard between balancer plugs. even the hobby ones have about 5 variations, so i figured ill just use whatever is around, given nothing is standard.

all the hobbycity chargers seem to be pretty decent really. they all come out of the one factory anyway lol. anything with 6 cell capacity and 7 amps ~ should be good. theres a few nice ones for $50 or so but this is the ultimate it seems. wouldnt mind one myself

http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=9005&Product_Name=iCharger_208B_350W_8s_Balance/Charger
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www.demon50s.com - Minimoto parts
http://www.youtube.com/user/HyzerGlen - Videoooozzz

Interesting, so basically no one can use anyone elses charger for their batteries.
That sort of sucks. But am probably ignorant here, Would gather no one actually balances their batteries at event, just fast charge them and balance them every so often, yes? so if anyones charger broke down, they could use another just to charge.

Personally i need to be able to do 8 cells, down the track (track - get it) will probably go 10 cells for bigger vehicles.

Any comments on the Astroflight 109
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Bots that do not destroy you, only make you stronger.

most of the cheep chargers from hobbyking and alike can take Hyperion ballance taps just have to break a tab off them which is easy to do.
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Remember to trust me, I am an Engineer.

http://www.youtube.com/watch?v=rp8hvyjZWHs

we use a DB9 plug on our batteries, we charge them in series and run them in parallel.

If you are using lipo you must charge with balancer unless you like fireballs on your bench. A123's are a bit more forgiving, everybody I'm aware of charges with balance all the time though.
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Mechanical engineers build weapons, civil engineers build targets

I've never even put balance leads on my A123 packs...
Good thing lipo packs come with them, or i might not have bothered either...
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YEAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAH

Many brands of chargers that have built-in balancers also have 'personality modules' that adapt different brands of battery - I can do at least 4or 5 popular brands with my Bantam E-station charger.

Like Jake said, balance every time of prepare for a BBQ-ed bot.