Starting Point

[zoll]

Thanks where can I find mod2.5 they only go up to mod 2 on technobots?

Edit: or do you think mod 2 is sufficient?

[Metal Demons]

To work this out properly I'd need proper specs on the motor concerned, a scale drawing of the whole system, and to do the maths properly, which honestly I can't be bothered to do

Rule of thumbing it, mod2 would easily work if the gears aren't pot-metal, I have no idea on the specs of these so can't say but they probably are fine and if they don't you can get some better gears from somewhere like ondrives.com (expensive though!).

Best bet though is to go for the chain drive! The reason why is that to get gearing to work properly you need to work fairly accurately, significantly better than +/-1mm, whereas you have a bit more leeway with chains - as (I'm assuming given that you're using wood and such like) you don't have access to accurate machine tools it'll be a bit of a pain to do the mechanism right. A chain drive reduction is a lot less finicky about clearances and everything being dead straight. In addition, unless your structure is extremely rigid (and therefore heavy and/or hard to make; a milled aluminium gearbox setup would be your best bet here), if it gets tweaked during a fight, say if you get hit hard, your gears will probably bind up.

Alternatively, there's the expensive way of doing things, which is designing the mechanism, accurately drawing it up (CAD is an option here), and getting it made at a machine shop.

[zoll]

Cool, I currently have it runing on chain and sprocket at the moment, was looking for a little bit more of a reduction then i can get with this and also, this may sound silly but a more refined sophisticated way of doing it.

If I was going to do it this way I would look to mount it between two Nylon 6 bulk heads, so hopefully a bit more of a refined method than wood!

[Metal Demons]

Cool, I currently have it runing on chain and sprocket at the moment, was looking for a little bit more of a reduction then i can get with this and also, this may sound silly but a more refined sophisticated way of doing it.

If I was going to do it this way I would look to mount it between two Nylon 6 bulk heads, so hopefully a bit more of a refined method than wood!

Just choose different sized sprockets to get your reduction the way you want it!

As for refined methods, for now I'd recommend getting something working reliably. Nylon is a good material, but really not stiff enough to hold a gear train in alignment - you'd be wanting to make the structure for that by milling it out of aluminium most likely. Save that kind of thing till you have access to decent machine tools, or the money to get parts made, or both

Just trying to save you some trouble, that's all Pretty engineering is all very well, but if you end up with a mechanism that jams up or doesn't mesh properly the effort is rather wasted.

[zoll]

Ok thanks for the advice . I may post this in the wanted section but is there anyone out there who could mill me some kinda gear box for my creation for around the £200 mark or is this way too little?

[Metal Demons]

Ok thanks for the advice . I may post this in the wanted section but is there anyone out there who could mill me some kinda gear box for my creation for around the £200 mark or is this way too little?

Kenny at ALK Engineering - look in the commercial section, or email him at kennyrobotics@hotmail.com - is the go-to guy for robot builders round here; he does top quality work for a pretty reasonable price.

Design something, draw it up accurately (CAD or otherwise), and have a word with him

[zoll]

Im rubbish in CAD so going have to attempt to do it by hand I think, Not quite sure how to attach the axe to the final gear, wither to attach it directly to the side like I have done with the spocket, or whether to try and get something like this done. Before I put too much more thought into it does £200 sound about the right ball park?

[zoll]

In the process of contacting kenny, had a first respone back but since that nothing for a while. Hopefully ive not put him off with my lack of design speaking of which anyone fancy designing it?

[psycho_fling]

Depends what your after i could have ago if you wanted

kenny might be away on holiday ???

hes usually on msn be easier to talk to him that way

[zoll]

Its been a while so I thought I'd update, I'm starting my first real job next monday so hopefully will have a bit more then my students pennies to spend. (Have also just moved to farnborough for my job, anyone in the area?)

No luck with the gearbox from kenny think he must still be making 180 ( which looks amazing).

So i thought I'd move onto another bit that I want to upgrade... batteries, think I want to go with some a123s how many would I need and in what configuration would I need to power a 24v scooter motor and two 18v drill motors. Also anyone making a suitable pack that I can buy lol. Also also recommendations for a suitable charger?

Finally I think farnborough college does night welding classes which I think might be useful so I can start to work with metal

As always thanks in advance