MegaSack DRAW - This year's winner is user - rgwb
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I've a project in mind which will require a turntable with counter-rotating spindles, about ooh 50cm or so in diameter. It's a fairly simple thing to envisage with a planetary gear set to make the spindles turn the right way, but where on earth does one get the gears to make such a thing?
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The best way I can imagine doing it would be a rustic style affair with the gears cut out of wood - anyone have any better ideas? Torque and speed are very low.
RS sell gears of various sizes and materials, and complete gearboxes. eg http://uk.rs-online.com/web/c/pneumatics-hydraulics-power-transmission/power-transmission-gears/spur-gears/. You could chop up an old Sturmey Archer hub
If you go down the wooden gears route you can download gear template generation software, a search on wooden gears for clocks should find one.
Also, buy good birch ply. Lesser quality ply is difficult to cut the teeth profile from.
peter, do you know somebody called andrew winterbottom?
could you just use friction or is there going to be a lot of load - fan pump belt from a car on the inside of the outer ring, wheels from kids scooter on the inside?
You could chop up an old Sturmey Archer hub
Far too small.
Friction - not a bad idea actually. Load is very low, it does need to be pretty consistent though.
I love these DIY threads. We get get to see some really beautiful examples of workmanship.
What are you making?
I've bought from this place before and found them good.
[url] http://www.davall.co.uk/davall-stock-gears/davall-stock-catalogue/gears/ [/url]
Ignore that, just got round to reading what you actually wanted 🙂
Draw them, or write a program to draw them, then get them laser cut out of perspex.
Oh yeah.. nice idea thanks.
What are you making?
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Phil,
Don't think so, any clues why I should ?
ahhh thought you might be the same peter starkiss who he used to work with.
what are you making molly?
A yarn twister. To make thicker thread out of thinner threads.
Couldn't you just do it with a variable speed drill and a round thing on the end with some hooks?
Are you making a furling machine ? Ive made one using 3 separate dc motors, using the same supply you can get more or less the same speed and therefore the same amount of turns, i was making 15 foot tapered leaders for fly fishing.
[url= http://www.hpcgears.com/ ]HPC Gears[/url] sell all kinds of gears in plastic or metal. Not sure they go quite as big as 50cm though.
Alternatively you could make them yourself from wood...
http://woodgears.ca/gear/planetary.html
Couldn't you just do it with a variable speed drill and a round thing on the end with some hooks?
Well no. This is about twisting multiple strands together to make one strand. If you just twist them together, they un-twist. To get it to stay together you have to twist each individual thread the other way, to get the strands to lock together.
That woodgears.ca link is fab! That may well feature heavily in this project! The stuff he's built looks just like what I had in mind.
I'm gonna need a scroll saw though...