One of the most difficult and yet common mechanical systems is a gear train. A great way to transmit mechanical power from one place to another or to increase or decrease power (torque) or increase or decrease the speed of something.

The problems are always that to make efficient gears needs quite a lot of drawing and mathematical skill as well as the ability to machine complex shapes.

For a lot of amateur work it isn't necessary to have maximum efficiency and therefore we can get away with a much easier to make, even with hand tools, system.

A gear is basically a series of teeth on a wheel.


provides a very good explanation of how gears work and how to work out gear ratios.

Step 1: Formula and Maths (the bad news)

Formula for drawing and making gear teeth are all over the web BUT they seem, to the beginner, very complicated.

from http://www.engineersedge.com/gear_formula.htm

So I decided to simplify the issue and it works very well at both large scale and small scale. At small scale it works best with machine cutting with laser cutters for example when very small gears can successfully be made this way.

<p>hallo sir</p><p>im going to attempt making my own 90 degree diff gears/ these will hopfully be driven by the wind for very small tasks. time is never a factor in my world. but i want to drive small machines and follow in the old steam fly wheel way/ wether water or wind. and in my city we have an endliss suply of wind. i wish to be able to put a saw blade to a log and let it carve its way threw. yes im nuts. thats why i dont mined trying differant opptions. any advice you could offer i would be humbled. ta rolfo</p>
<p><a href="http://www.vintageprojects.com/machine-shop/power-hacksaw-plans.html">http://www.vintageprojects.com/machine-shop/power-...</a></p><p>A good sound plan to build a powered saw.</p><p>If you want to try wooden gears you may be better off looking at how wind mills and water mill gears were made. Yes they were wood and they did withstand heavy loads (at low speeds) so you may be able to do this.</p><p>I would reduce the speed of the wind mill by using pulleys and belts rather then gears as wood gears at very high speeds are less reliable.</p><p>Accuracy will be important to get a smooth running system.</p><p><a href="https://www.google.co.uk/search?q=water+mill+wooden+gears&biw=1920&bih=953&source=lnms&tbm=isch&sa=X&ved=0CAYQ_AUoAWoVChMI0vGSwez7yAIVC1wUCh2zBwC1">https://www.google.co.uk/search?q=water+mill+woode...</a></p>
Thank you very much!!! Excelent tutorial
<p>congratulations on an absolutely brilliant idea for making gears not merely easily but ridiculously easy. Your design may be used for all sizes of gears and almost in all metals which are workable by hand tools. These circular teeth gears are not to be considered as some sort of apology for the real thing. These gears are the &quot;real' thing. Absolutely superb for craft work, working models and just about any device or mechanism requiring gear sets. If they are greased or even run dry the operate totally satisfactorily. I have used your design for the knee joint on a brace. Congratulations and all the very best to you.</p>
<p>Your welcome - Enjoy.</p>
<p>Thanks for sharing! If you need PDFs with technical documentation see our <a href="http://www.varvel.com/en/download/catalogues" rel="nofollow">gearboxes catalog</a> or get in touch for CAD models!</p>
<p>This is great, thanks! I will try this design on my 3d printer. I am trying to use gears to help kids in 6th grade understand ratios and proportions with a hands on application. Love that it includes a lot of circle calculations. Any suggestions on simple applications of these gears?</p>
<p>You could always make a simple drive train, using about 2 big gears and 2 small gears to make a slow input into a faster output.</p>
<p>Great instructions!</p>
<p>These are brilliant and not that hard once you understand it</p>
<p>That's really cool</p>
<p>I got the program Gearotic and it has changed the way how I draw gears it has made it so simple, Check it out.</p>
if making gears is too difficult, you can use sprockets like I made here:<br>http://www.instructables.com/id/simple-wooden-sprocket-without-cnc-machines/<br><br>but good work rickharris
I'm intersted in making gears and I've read somewhere that gears are the hardest mechanical components to make without proper tools.Your instructable is good and teaching from this point of view.
Thanks - To make correctly shaped gears is a little more complicated - there are lots of on line calculators and explanations of why they are that shape.<br><br>This is a way to make gears at home that for low pressure system work quite well. <br><br>large size you can make with a drill and round file, smaller sizes really need some kind of machine to cut them. A laser cutter works very well as in my picture.<br><br>thanks again.<br>
Nice article, <br><br>Just bear in mind, there are very good reasons why gears have the profiles they really do !
:-) Yes I know - BUT for much hobby use the sinusoidal gear if not heavily stressed works as well and is much easier to construct with very basic tools.<br><br>Remember for hundreds of years Windmill manufacturers got by with simple squirel cage and pin gears.
You'd like Mathias Wandle's gear generator Rick. Steve has it, it's brilliant.<br> <br> <a href="http://woodgears.ca/gear_cutting/template.html">http://woodgears.ca/gear_cutting/template.html</a><br>
Yes I have seen that and used it - Works great and his wood work is fantastic. <br><br>There are other sites that provide gear drawing software as well - I believe inkscape has a gear drawing engine in it .<br><br>This is just a very simple way for someone to do it with basic compass and pencil tools.
I'm a big fan of Wandle's site it is defiantly worth looking at
Very useful.-

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Bio: Retired technology teacher - 2 kids, I have an Hons deg in Design and Technology - 28 years as Computer systems engineer Trained as Electronics engineer in ... More »
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