8_10 Brass Cleaner
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Meccano Gears - Reduction?I'm just trying to get my head round meccano gearing.
If I use a worm how do I work out the reduction?
The way I see it, for every revolution of the worm, its mating gear will turn one tooth, so with a 57 tooth gear, the reduction is 57:1
Am I correct?
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wart
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gearingmy brian hurts
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wart
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gearingi mean brain
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Spokesmann
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I need my Meccano gears booklet! From memory the worm drive provides a great reduction in ratio - the most I think, it all depends on the gear/pionon driving onto it, the bigger the gear the bigger the reduction, normally divide the larger by the smaller to get the reduction. Ill see if I can locate my Meccano gears set, it has the whole lot set out in really clear english what each pinion, contrate, gear or worm drive will give when employed in any combination.
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John Chapman
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Re: Meccano Gears - Reduction? | 8_10 Brass Cleaner wrote: |
The way I see it, for every revolution of the worm, its mating gear will turn one tooth, so with a 57 tooth gear, the reduction is 57:1
Am I correct? |
That's spot on .
Gear ratio is expressed as the number of teeth on the driven wheel divided by the number of teeth on the driving wheel. So a 60 tooth wheel driven by a thirty tooth wheel gives a reduction of 60 divided 30, i.e. 2:1
A worm gear has only 1 tooth so as you say a worm used with a 57 tooth gear gives a reduction of 57:1.
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fcrammond
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I second that 
F
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Chris
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Thirded (if that is a word) here. That is correct, a worm gear counts as a gear with one tooth so you get very large reductions using one.
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8_10 Brass Cleaner
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| Chris wrote: | | Thirded (if that is a word) here. That is correct, a worm gear counts as a gear with one tooth so you get very large reductions using one. |
Ta gents, thanks for confirming that. Did meccano make double lead worms?
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Spokesmann
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This may be of interest...
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Scorpion2nz
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nice simple differential but whats with the chain sprockets Could you not fine those damn elusive brass collars 
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Spokesmann
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| Scorpion2nz wrote: | | nice simple differential but whats with the chain sprockets Could you not fine those damn elusive brass collars |
Didn't have any at the time.
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steamyjim
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So i'm not the only one to have trouble finding those brass collars?
I might have to machine myself some as I am realy running out 
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fcrammond
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Double lead worms? Not that I am aware of. I'm still trying to get my head around what advantage they would have.
F.
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fcrammond
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Collars are usually made by buying up aa load of old, battered pulleys and machining them down to size (also the brass bits of those useless black quarter inch plastic pinions after they have split )
F.
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8_10 Brass Cleaner
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| fcrammond wrote: | Double lead worms? Not that I am aware of. I'm still trying to get my head around what advantage they would have.
F. |
It would halve the reduction. Just wondered.
Perhaps I shall make one.
hmm
Now my brain hurts, could I just alter the pitch?
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Scorpion2nz
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| fcrammond wrote: | Collars are usually made by buying up aa load of old, battered pulleys and machining them down to size (also the brass bits of those useless black quarter inch plastic pinions after they have split )
F. |
if it is plastic then not REAL meccano in my opinion
no need to machine battered pulleys just reclaim from old tin wheels
easier to cut to length have a large bag here waiting to be dealt with
but then no rush as have more than sufficient collars
but might instead make some dog clutches
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fcrammond
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Meccano produced a range of plastic gears with brass centres. The black quarter inch versions suffered from a failure mode that separated the plastic component from the brass core. The brass core turns down nicely into an ersatz collar.
A similar operation can be carried out on the one inch pulley wheel which most of us have to excess. I haven't found a use for the surplus wheel discs yet
Fred
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fcrammond
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It would halve the reduction. Just wondered.
Would it? My brain is hurting too.
F.
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