Engineering Problem

OK, here is the problem...I need to turn the drive from an S28-150 Magmotor through 90 degrees, I need to safely deal with both the max torque of around 13.5Nm and shaft speed of around 6000 rpm, my original idea was to use a set of induction hardened Mod. 2.5 straight cut (Gleason System) bevel gears but I have been warned that although it would work, that it could be very noisy. Would I be better off using a set of spiral cut bevel gears?
Or can anyone think of a better soloution.
Thanks

Geoff.

(Oh yes, one other thing, it needs to be as light as possible!!)

Geoff you got the money, why dont you just buy one of those funny name teams gear boxes specialy made for Mags. Team Wy thingy. LOL! And its light.

Mr Stu

http://www.teamwhyachi.com/Twm3R.htmhttp://www.teamwhyachi.com/Twm3R.htm
Something like that Geoff ?

Only 1.8kg there Geoff. LOL!

Mr Stu

Ok 1.81437kg!

Been there, seen them! Thats the sort of thing, but at 1.8Kg theyre WAY too heavy! also they have a 2:1 ratio I need 1:1 :sad:

(Plus at the moment $345 + shipping is just not on! :sad: )

Having a mag motor in the first place is not on! LOL!

Mr Stu

Nah, having a Mag motor in a feather is not on! But as regards to you problem just dont do it in the first place hehehe! :P

Chris

Apparently they do customisations too.

http://www.teamwhyachi.com/botshop.htm

Does anyone else think a magmotor is overkill? I know I do.

So you havnt met our Astroflight powered featherweight spinner or our Lynch powered heavyweight spinner yet have you Ceri?!! :proud:

Anyway, this one is for the girls to play with!:wink:

But seriously for a moment, anyone got thoughts on the original problem?

Mag Motor is over kill but whos going to stop him its his bot and theres no rules against it so all we can do it beg and plead :sad:. Vortex proved that they are OTT for british featherweights even Ti clad U.S. 30lbs still struggle against Mag powered weapons. :uhoh:

quote:

Anyway, this one is for the girls to play with!I think that scares me more than the thought of using a Mag motor in the first place. :proud:

Seriously though all I can think of is find out what gears Team Whyachi use, and build you own 90 degree gear box as light weight as possible.

Chris - Coalition Against Mag Motors In Featherweights :crazy:

I wouldnt worry about the noise, it is half the fun after all ;)

Regards

Tim

Geoff, I can make you that gearbox. And not for £25 labourcharge an hour. Contact me.

Trilibium uses a mod 2 beval gear and its well niosy!. why not go for it and enclose it in a 1mm ali box, fill it with grease and it should be fine. as long as the ali isnt suppoting the bearings the shafts run in.

I would of thought helical gears were another option? Not sure on there effeciancy etc but itd do the job. As James said if you make an enclosed gearbox it should block out a fair bit of noise and keep the gears swarf-free :)

The problem with bevel gears and in particular spiral cut bevel gears is the huge lateral loads they put onto the supports. This requires a chunky gearbox with heavy bearings. If you are planning to use this gearbox for a spinner, the tough supports and big bearings are what youd want anyway.
If youre using it for anything else though I can think of some lighter alternatives Only thing is they would take up more space and are probably not as robust.
1. Universal joints. you would probably need at least three joints in series, with bearings supporting the intermediate shafts.
2. flexible shaft:http://www.lara.com/cgi-bin/store/commerce.cgi?oc=WI-FDhttp://www.lara.com/cgi-bin/store/commerce.cgi?oc=WI-FD
They would probably take the torque and might even allow a bit of cushioning to pretect the mag from impact torques. You might have a problem with them whipping so youd have to support them along their length. This would take space but not much weight.
3. polyurethane belts twisting through 90. This could work well and be light. 8mm belt around 80mm pulleys should be able take the torque.

Geoff, Youve seen big nipper, we use right angle drive threw bevel gears and they are not noisey (well not much), maybe you could use something like this, they have thrust bearings behind them. They are out of Roder plants gearboxes and they are not hardended, if they work for our drive then they should be OK for you. They are not normal bevel gears and have a strange teeth profile (nearly flat) and are bigger than mod 2.

A picture of them is here:
ftp://http://www.bignipper.no-ip.org/Series%207%20Big%20Nipper/Making%20of/Picture%20010.jpghttp://www.bignipper.no-ip.org/Serie...ture%20010.jpg
But its quite big (1.7MB). Of course you would save weight if you didnt use 1 thick Ally for the mounting.

RS sell some small right angle drives but not sure without looking them up what torque they can handle.

Another suggestion is to use the gearbox of an anglegrinder (something we are considering) and these are rated at those speeds and are quite strong and light and cheap.

I dont know when you are coming up to denbigh next weekend Geoff but there is a pretty big ex-MOD scrapyard in the town. They sell tons of parts, hydraulics pneumatics and gears of all shapes and sizes. Also sell manganese steel (armour) too. The catch is that they are closed on Saturday.

quote:

So you havnt met our Astroflight powered featherweight spinner or our Lynch powered heavyweight spinner yet have you Ceri?!! :proud: - Geoff

True, I havent had the oppurtunity to meet those 2 in battle, yet.

I also dont want to :uhoh:

Thanks for all the input guys, I think I need to give this some further thought.
Ceri, both of our machines will be at Denbigh next weekend, If you can make it, introduce yourself and Ill give you the guided tour!

Geoff.

Id stay away from Geoff, dont accept the sweets he gives you!

LOL!!

Mind you the ones from his Wife and the other Female member sweets are nice. Should i be worried? Naaaa!!!!!! LOL!

Mr Stu

If the load is going to be a problem how about having the output from the gears drive the disk via a belt, and take a bit of the hurt out of the drivetrain.

an angle grinder gearbox would prbably be the simplest thing. they are designed for very high speed 1:1 gearing, but i dont have much of an idea about the shock at load they can take.

Just thought you guys might like to see what Im planning to put on the new machine. (Check profile) That is nearly 3Kgs of 6mm thick Chrome Vanadium steel 345mm in Diameter.

Oh no fair lol! S28-150 Magmotor and a 3Kg Pussycat type blade! :crazy::lol:

Chris - http://www.featherweights.org/forum

you burgled mr Gribble Geoff?

To be honest, Id ask a professional, well established engineering company to come up with a solution for you geoff, you could waste a lot of time/money trying some of the solutions above only to find they wont work.

Failing that, contact Red Bull racing and ask for a titanium differential gearset.... should be light enough and strong enough. bit of WD40 on to grease it.... lol.

I would go for the spiral bevel gears mod.2 or for helical gears. Also mod.2 Check this website, im sure they can give some advice.

http://www.hpc-gears.co.uk/products.htmhttp://www.hpc-gears.co.uk/products.htm

If anyone is going to ask there for some prices, please ask for me the price of a toothed bar stock, 15 teeth, mod. 0,7 in brass and steel. This should be the same size of gears as in my cordless drill gearboxes. Then i can cut them to the lenght i want and put a bigger motor on the gearbox. :)

I would stop giving Geoff advice

:oP

Ed
http://www.teamstorm.comhttp://www.teamstorm.com

Never mind that Ed, have you noticed Little Spinner yet? I hate to think what Graeme has come up with this time :)

:)

How far did you get with this in the end Geoff?

It looks like somebody else had the same issue at around the same time but on the other side of the pond: http://www.buildersdb.com/botdetails.asp?botid=4290http://www.buildersdb.com/botdetails.asp?botid=4290
Dick got the power through 90degrees using friction drive with a colson on the mags output shaft. Given he destroyed everyone at Motorama I assume it worked quite well..

http://server.stuplich.net/~dick/cybershot/moto2006/http://server.stuplich.net/~dick/cybershot/moto2006/

F-Bomb also only runs on 12v.... And still trashed TO who runs 24v.