Geared Candleholder

This project is a candleholder with three gears and parallel action arms which move the candles up and down at different rates.It is made from aluminum plate and uses tea lights or small floating candles. The design and the variable gearing make it a playful device.

Step 1: Marking and Cutting the Gears

I make gears basically by drilling holes in a circle, and then cutting away excess material so that the holes become the "valleys" between teeth. The diameter of the circle that passes through the center of each tooth (the Pitch Circle), is calculated by the formula shown below.

Also note the additional holes marked "#25". These are mounting holes for the connecting rods that join to the parallel arms. They need to be drilled with a #25 drill bit, and then tapped with a 10-24 tap to accept the shoulder bolts that act as pivots for the connecting arms.

Step 2: Cutting the Chassis Plates

The front and back plates of the chassis are cut from 1/4" aluminum plate. Use the chart below to mark out the back plate, then use the back plate to mark up the front plate (remember the front plate does not have holes for the gears, so it can be much smaller and simpler.

Step 3: The Feet and Knob

The feet are cut from 7/8" diameter aluminum rod. I cut slots in the rods to fit the front and back plates of the chassis into. During final assembly, you will epoxy the feet in place.

The knob can be any shape, but I made it in a similar shape as the gears. It needs a center hole, 1/4" dia., and a 1/4" shaft collar joined to the knob with a tension pin (see photos). 

Step 4: Arms and Candle Brackets

The arms are cut from 1/8"x1/2" aluminum flatbar. See chart below. You will also need to cut spacers for the arms so that they don't collide with each other or with the protruding bolts that hold the gears to the chassis. The candle brackets are made from two pieces of the same material, plus a disc cut from some other plate (I used 3/16" aluminum plate). The discs are drilled and the bracket pieces cut so that they form tenons which can be staked to the disc. Finally, a glass drip ring (these are also called bobeches) is epoxied to the disc to hold the candle in place.

Step 5: Assembly and Finish

I brushed everything with scotchbrite pads to leave an even finish. I used wave washers to add tension to the mechanism so that the candles wouldn't just flop down. I also added blue threadlocker to the joints so that they would not come undone accidentally.

Comments

[Edgar]

Nice!
The gearwheel making part will be used by thousands of Gizmo Makers, now:
http://faz-voce-mesmo.blogspot.pt/2013/03/acendedor-de-churrascada-electricidade.html

[alvin_lee]

It's amazing to see how you make gears without CNC or the gearing cutters of some sort. It's just amazing! You are the pro, man!

[jimwi]

Benjamin it is nice to see someone using there hand to make things and develop there skills instead of cutting all the pieces out on a CNC mill or laser cutter. You do very nice work. Thanks for shearing. JIM

[action pig]

Loved it. Would love to see a video!!!

[jtmcdole]

+1

[lurker99]

ditto

[Sam DeRose]

wow this is amazing. awesome work!
can you post a video of the movement?

[JamesRPatrick]

This looks really familiar.

[l8nite]

it's a great mechanical sculpture, it would be over the top if it was motorized

[KoomoriForge]

Brilliant work, Benjamin! Thanks for sharing.

[Penolopy Bulnick]

Sweetest candleholder!

[luridhue]

Incredibly beautiful. I'd love to see a video of the motion when turning the knob. I am impressed that it is all cut/finished by hand, on first glance I presumed it was CNC milled or the like and beyond what I am able to make through lack of a mill, I have a lot of brass plate sitting around and will have to give this a go. Thanks :D