Assembling the components

Assembling the components

Contents of this tutorial:
How to use this tutorial
Step by step instructions
Finalizing and tuning

How to use this tutorial

To view the animation to the left you will need to install Quicktime
There is also a YouTube based version, if needed, but the Quicktime version is recommended for better playback and control.

The best way to view the animation is to click and hold the time slider at the bottom and move it left and right to view whichever part of the animation you like, at your own speed.

You can download the animation here (right click, 'save link as'):
High quality (24.7 Mb)
Low quality (2.5 Mb)

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Power drill
(Corded is best, battery will do)
3mm, 6mm, 12mm metal drill bits
Phillips or flat, depending on your screws.
Wood saw
Needle nose pliers


50-60cm small wood plank

Something a couple of centimeters by a couple of centimeters.

2 bicycle cable tensioner bolts, also called cable adjusters

Most bikes have these to keep the brake and gear cables tight. There are two kinds, the larger ones with a cut down one side, and the smaller ones without. Don't use the ones with the cut.

8 M6 80mm bolts

Get ones that are threaded all the way to the head.

9 M6 nuts

4 M3 nuts

3 short wood screws

2 medium / large washers

With holes small enough to hold the wood screw heads.

6mm clear PVC tubing

One length of 80-90cm, one of about 30cm.

6 small / medium cable ties, also called zip ties

You can also use thin twisting wire.

Teflon tape

Gaffer tape, also called duct tape, cloth tape
Flat metal

To be cut into squares for weights.

1 liter of ethanol

You can get this from a lot of camping stores, pharmacies, discount stores, etc. Make sure it's definitely at least 95% actual ethanol! Don't use isopropyl alcohol, methanol, or anything else. It's often also called denatured alcohol, or methylated spirits. If in any doubt, contact the manufacturer and check.
Do not drink it.
Do not expose to naked flame.
The fumes won't do you too much damage, but try not to inhale massive amounts of the stuff.

Optional things to make your life easier:

Thin M6 spanner

Step by step build instructions

These relate to the animation to the left.

Step 1:

Take the finished Gearing assembly and Main Collector.


Put the bolt emerging from the middle of the collector's front face through the hole in the square metal at the top of the Gearing's shaft. Wind a nut onto the bolt, but don't tighten completely, leave a couple millimeters of space between it and the metal.
This may be bit fiddly, depending on the position of the wooden cross beam above the bolt, which you may need to temporarily remove it if you can't reach in with needle nose pliers.

With a thin spanner or needle nose pliers, tighten the nut on the inside of the collector, so that the bolt is now locked to the collector wall. Make sure that the copper collector pipe can rotate freely around it, without much friction.

Drill a 6mm hole in the collector panel to line up with the other hole in the square metal.

Insert a 6mm bolt through the hole and tighten with a nut. The Gearing shaft and Main Collector should now be locked firmly together.

Take the finished Wheel assembly.

Drill a 12 mm hole which lines up as closely as possibly with the Gearing's spring worm gear shaft.

Drill four 3mm holes for the bolts protruding out the back of the Wheel. The easiest way to do this is put some kind of adhesive tape on the metal, insert the Wheel's shaft into the 12mm hole so that it's lined up with the worm gear shaft, then press the 3mm bolts into the tape so that they leave an impression, which you then drill.
Make sure the 3mm bolts are protruding straight from the back of the wheel. Bend them with pliers if they're crooked.
And make sure the jar attached to the wheel is going to be more or less pointing down when the SolarFlower is tilted up to the sun.

Bolt the wheel in place. Adjust the height of the 3mm nuts on both sides of the metal so that the Wheel sits straight, lines up with the worm gear shaft, and that the cans can turn freely without the nuts on the shaft touching the metal.

Attach the Wheel shaft to the worm gear shaft with several tight turns of gaffer tape, held firmly in place with cable ties or twisted wire.
The forces on this won't be large, so it shouldn't slip, but if it does replace with something like plastic tube glued in place. It's best though to use something that can be removed if you want to take the wheel off for some reason, and make sure to use a connection which is at least slightly flexible to accommodate any misalignment of the shafts.

Take the finished Frame.

Attach the Gearing to the Frame with a bolt, as shown. If you want you can attach firmly with nuts, but it shouldn't be necessary.

Lift the Collector plus Gearing so that it's over the cross beam at the back off the Frame.
If you didn't drill your seasonal setting holes when you were constructing the Frame, do that now, measuring the angle of the Collector with an angle level or similar.

Insert the collector pipe's bolt through the hole drilled in the cross beam and attach with a nut.

Attach the Gearing to the Frame with a final bolt, as shown. Screw on the wood and drill a hole for it if you haven't already.
It's important that the device not sag at the connection between the Gearing and Collector, so make sure that with this bolt the Gearing shaft and copper collector pipe are in as straight a line as possible.

Now reset the device to each of your seasonal settings by unscrewing and repositioning the cross beam at the top of the frame. Drill an additional hole at the front, as above, for each.
The Frame construction tutorial has more information on seasonal positioning.

Take the finished Box Collector and a 50cm length of thin wood, and attach as shown with two short wood screws with large washers.
If you're in the southern hemisphere this will be with the long bit of wood to the left, as shown, if you're in the north it will be on the right.

Place the Box against the front face of the Collector so that the short end of the 50cm wood sits just above the Collector's cross beam with about a 20 degree angle between them and the Box's metal tin tucked against the Gearing's shaft. The closer it is the less it will unbalance the device, and the less counterbalancing you'll have to do.
The Box will be more precisely positioned in a later step.

Drill a hole in the short end of the thin wood and through the face of the Collector.
Attach with a bolt and nut.

Attach the thin wood's long end with a short wood screw.

In the top of the wheel drill holes for and attach cable tensioner bolts as outlets from which the ethanol will pour into the cans. You'll need one for each seasonal setting you plan to use (two is recommended, one for summer, one for winter, or just one if you only plan to use the device for part of the year), and they'll need to be positioned so that the stream of ethanol is always pouring into a can, as shown below:

If the outlet is outside the green area then it will be possible for the ethanol to miss a can and the device will stall. This doesn't need to be extremely precise, and if you think you've not put it in the right place just drill another hole and relocate the outlet. (Make sure to tape the old hole to prevent the ethanol evaporating.)

NOTE: whether the outlet goes on the left or right side of the wheel depends on your hemisphere, which side of the gearing you put the wheel, and whether your spring winds clockwise or anticlockwise.
Turn the wheel with your finger and see which way the collector goes. Put the outlet on whichever side will result in it tracking from east to west when it's facing the sun.

Set the device to each of your seasonal settings and insert an outlet for each.
See the Frame construction tutorial for more details on seasonal adjustment.

Attach an 80-90cm length of 6mm PVC tube between the valve in the base of the reservoir under the wheel and the cable tensioner bolt at the bottom of the Box's boiler. Wrap the bolt's thread with a few turns of Teflon tape and secure with cable ties or twisted wire.

Repeat with a roughly 30cm length of PVC between the valve at the back of the Box's metal tin and whichever of the Wheel's outlets you will be using for this time of year.
Block off the other outlet(s) with a dome nut, tape, or similar to prevent the ethanol from evaporating.

Test that everything is working properly by turning the wheel with your finger. It won't be perfect until the device is counterbalanced, but watch out for any rubbing or excessive friction.

To fill the device detach the shorter PVC tube from the top of the wheel, then remove the bolt attaching the Box to the Collector and flip the Box upside down. Unscrew the reservoir from beneath the Wheel and pour in about 600ml of ethanol, then lift it above the level of the Box so that ethanol starts draining into the tin. If your reservoir doesn't hold that much, refill it while it's draining.
When ethanol starts coming out the tube attached to the tin screw the reservoir back onto the wheel, then reattach the Box to the Collector and the tube to the Wheel.

The device doesn't need to be oriented extremely precisely, but the closer the better.
If you're in the northern hemisphere you want it pointing due south (as in, polar south, not magnetic south) and north for the southern hemisphere.
The easiest way to do this is find solar noon (the time at which the sun is highest in the sky) for that day, which you can do by entering your country and closest town into this widget:

or by getting the times of sunset and sunrise where you are and calculating the point halfway between. These are easy to find online or in your local newspaper.
For example, if on the day you plan to orient the device the sun will rise at 6:00 am and set at 8:38 pm, then solar noon would be at 1:19 pm.
Then just place the device out where you want it at that time and turn it towards the sun until the shadow from the collector pipe is running exactly down the center line of the Collector trough.
But even if you're off by several degrees, it shouldn't make a huge difference.

This is something you want to get right. If the device is well balanced it will be practically frictionless and require very little force to turn.
To do so, knock the pieces of metal holding the Gearing's worm gear shaft away from the large bike gear (called a sprocket) with a hammer so that they no longer touch and the Main Collector can turn freely.
Drill a hole in the four corners of one of the Collector's plywood faces and insert a long bolt in each. Take some flat scrap metal, cut into squares, and drill a hole to fit the bolt in the center. These are your weights. Refer to the images below as to where you want to add them:

If the Collector falls to the left, add weights to the bolts on the top right and bottom right.


If it falls to the right, add weight to the left.


If both sides fall away from center then it's top heavy, so add weight to the bottom left and bottom right.


If it falls towards center on both sides it's heavy on the bottom, so add weight to the top.

Keep turning the collector and letting it settle, adding and removing weight, until it no longer falls in any particular direction and stays where you leave it.
Put a nut on any bolts with weights to stop them sliding off, and return the spring worm gear to the sprocket.

It should take about 10-30 grams of force to turn the collector, two or three large metal nuts in one of the cans should be able to do it.
If not, check that the shafts are not rubbing or catching on anything, and that the spacing between the spring worm gear and sprocket is such that there's a small amount of wobble; not so tight that they grab on each other, but not so loose that they can detach and slip. Tune with a hammer, lightly knocking the two pieces of flat metal holding the worm gear shaft in place, moving the spring towards or away from the sprocket.
This is the main point where friction and other problems can arise, so it's worth taking your time to get it nice. Check back every so often as the device is working to make sure this is still as it should be.

The Box needs to be at a precisely 20 degree angle to the Collector. You can do this by measuring, but the best way is to rotate the Collector so that it is pointing directly at the sun, remove the screw holding the Box in place and adjust its angle so that the focused light is sitting just off the edge of the flattened copper boiler. As the sun moves off the Box's focus should shift onto the boiler before the Collector's focus has left the collector pipe.
Return the screw to lock the angle. This is the setting of the SolarFlower's overall accuracy, so it's important to get it right. If you later find that the angle is slightly off just remove the screw, adjust, and reattach.

And finally; the wheel should be pretty much airtight, but you want to keep evaporation of the ethanol to a minimum, so it might be a good idea to paint white any faces of the plastic container which are going to be facing the sun.

The SolarFlower is complete!
What happens next depends what you want to do with it. Tutorials on applications will be added to this site as they're completed, check the Forum for information from other users.

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