DiVER: mobile solar panel

Prototype milled out of 4mm plywood, the top may be out of glas or just coated for light use. However, the plywood is already warping a little bit, so I guess a glas panel on top is a must :frowning: Any recommendations for gluing glas onto wood?

Thanks to Oliver for handing out some raw solar panel wafers! :slight_smile:

Heyy! That looks great. And Nikolay will be ultimatively happy when seeing this living proof, that the new Logo ist mortiseable :laughing:

Glas would give additionaly a better shelter. The warping can maybe avoided when using MDF-Plate instead of plywood. But the plywood looks more stylish, what you have there is in my opinion Mahagony. I would use some linnen oil to give it a nice finish.

Good work!

regards, Oliver

It’s plain birch plywood, the color is indeed mahagony (kurz gebeizt und geölt mit dem Lappen wo eh noch Beize dran war…)
I won’t oil the surface for now because I don’t know if the glue will stick to the oiled surface just as good.
Now searching for glas… let’s see if I can cut some decent glass panels and glue them on top. Does the household silicon (without acid) work here?

One prototype finished. The clearance for the wafers is fine, I’ll try to solder the panel tomorrow and then mill another set. It’s super easy to position everything with the CNC milled baseplate. I’ll try to bring the wafers closer together and leave out the connector-maze inbetween :smiley:

I will also try to solder some wires onto the nickel plated neodym magnets, that way I might use the magnets as electrical contacts, not only as a mechanical connector. If the magnets can’t be soldered, I might solder a piece of steel to a copper wire and just tack it onto the magnet. The magnets are only 3mm in diameter and 3mm long (cylindrical) - the connection may be unreliable and the resistance too high for the 8 A_peak…

I looks like the so called sipo-mahagony. Its a cheap kind of mahagony and often used at the top layer (or back layer) or for each second layer. Other layers may be from birch, so that the whole thing is called birch plywood.

( from http://www.holzlexikon.modellskipper.de/Holzarten_Abschnitt_S/Sipo_Mahagoni.htm )

(from http://www.nauticexpo.com/prod/world-wood/boat-deckings-laminated-wood-panels-23592-104505.html

Birch looks like this:

(from http://www.holzlexikon.modellskipper.de/Holzarten_Abschnitt_B/Birke.htm)

Now searching for glas… let’s see if I can cut some decent glass panels and glue them on top. Does the household silicon (without acid) work here?

hmm, good question. Im not shure about how long it will last, whetherall it may glue in the beginning. And intuitvely i would assume that it would glue better if there is a finish on to it, of course the finish must be completely dry before glueing it. Linnen-Oil-firnis will become dry within one or two days.

At least the silicon will give a certain seal, maybe you can fix the glasplate additionally with strong tape wrapped round the edges twice.

Gruss, Oliver

Right, it really looks more exotic than birch. I didn’t know that there are that cheap versions of mahogany!

I am now doing some CAD/CAM work to mill picture frames. Those cheap ones with a frameless glas layer on top, held in with 6 clips which hook into the cardboard (?) backside. Those clips are pretty neat, I’ll use them for securing the glas ontop great for temporary use without any glue.

Backside with metal clips to hold the front glas. A tiny magnet connects the panels to a modular grid, the metal clips double act as connectors:

Thats a good idea with the clips!

Since they are reversible this offers lot of flexibility, especially in the beginning/testing phase.
This construction may also let the heat better escape than a complete encapsuled one.

I am courious how the magnetic connection will work, but the double use of the clips as contacts makes sense.

regards, Oliver

Just a tiny magnet sandwiched between the clips. Can be superglued (with a dot of CA = cyan-acrylate) to one clip so it will come off only on the e.g. positive side of the panel when you disconnect two modules. A 3mmx3mm magnet is sufficient for testing, for a long panel I’d use larger rectangular magnets instead.

The maze for the cable relief turned out really useful and totally does it’s job.
The only thing left to do now is to get 20cm x 36cm glas panels for the top. I tried to cut some glas myself out of a 30x45cm panel, but that didn’t work out well.

Very cool !!!

Looks, as if the thick wires in the maze help to keep the cells down with being formschlüssig (shape-fitting ?).

And nice, that the magnet stuff works also. But if you glue it would it be still conducting ?

The thing contains also an intelligence-test-question: if you have clamped the glass on it, you could not weld the clamps. But if you would weld them before then you are not able to move them for clamping the glass under them :wink:

Its a pity that the glass is to short, i assume its from the picture frame. However, one can get the idea already how it will look like later. Nice done !

regards, Oliver

Well the cells are kept in place even without glue or any connections due to the milled pockets in the baseplate. I milled the pockets 0.4mm deep, but 0.3 would suffice - I didn’t know how much the solder and the copper tabs would add to the 0.22mm wafer height before.
A drop of varnish can hold the cells in place sufficiently. For anything else but a prototype assembly… I guess I would put a thin coat of clear silicone on the glas front and then but the assembled baseplate on top. However, even with a water tighteningt treatment, the design is not really weather proof with wood as a baseplate. For a permanent modular installation this design could be used with some kind of plastic or metal (insulated/coated) as a baseplate. However, that’s not the aim of this design :wink: It’s pretty lightweight and easy to carry in a bag right now. I want to try acrylic glas rather than real glas, because the glas weights the most of this setup.

And nice, that the magnet stuff works also. But if you glue it would it be still conducting ?

Yea! You just put the magnet in place (metal-on-metal) and then add a drop of CA :slight_smile: No glue between the surfaces.

The thing contains also an intelligence-test-question: if you have clamped the glass on it, you could not weld the clamps. But if you would weld them before then you are not able to move them for clamping the glass under them > :wink:

They are all just soldered, not welded or brazed. :slight_smile: The clips can be soldered really easy with either the glas clamped in place or before clamping the glas on top. In the wiki entry is another picture of the backside assembled.

Thanks! Yes those glasses are from the picture frames, which I took apart for the metal clips and the general brainstorming…

regards, Oliver[/quote]