All pictures are of finished product, but it is not so complicated, or with other words - Im too lazy to interfere my work to take pictures :)
Step 1: What You Need
- a bicycle
- a notebook, preferably subnotebook, definitely not the 15inch widescreen one
- plywood 5 layers, 6mm thick, two times 16X22cm=, two areas of your notebook
- 17 pieces bolts with 7mm nuts, 10mm long, 4mm thick, conical head
- 9 screws for plywood, same length or few mm extra as plywood thickness. I had 11mm long, 8mm measuring without head
- 4 long screws for wood, some 2cm long
- 1 long nail, some 10cm long and 4mm thick
- 2 bricks of wood, approximately from 2 to 4 cm wide, some 5 to 8cm long and at least 4cm high. But this depends on your bike. My bricks were 3cm wide, 7.3cm long and 4.5cm high
- wire rope 4mm thick ~1m (for 1kg eeepc)
- 4 metal parts 1-2mm thick, 12mm wide and 14cm long - almost as long as your notebook. I got those from an old metal constructor set from my childhood. It has holes every 12mm.
- another same type metal part to hold your construction to your bike
- some aluminum sheet, not more than 10x10cm. I got mine from an old CD-ROM drive.
- little bit of rubber, sponge or other soft but firm material 1mm thin. I didn't need it, as my old CD-ROM had it glued inside already
- 4 rubber rings, fasteners 1mmX2mm thick and approximately 4cm diameter. Any rubber would do.
- plywood saw
- metal saw
- power screwdriver, also to be used for drilling holes
- drill bit for wood 4mm
- drill bit for metal 4mm. Quality should depend on your metal hardness.
- metal file, to shorten too long screws and to work on edges
- hammer, necessary even if working with electronics!
- vice, to hold your work
- ruler, a bit longer than width of your notebook
Time to work on this, one afternoon, probably few hours. Not sure as i spent a week with some trial and error returning to previous steps.
Step 2: Lower Part, the Stiff One
The last thing to this step is to add the fifth metal part. It needs to be so long, to be bent around your extender pipe and come to the nail and have holes at ends for the nail to go through. So it is bent like a U and has holes. When you will attach your construction to your bike - put the shelf on your bike, so the bricks slide around the extender pipe, slide the U metal thingy from downside in between the extender pipe and wood bricks and slide the nail inside the wood bricks holes, and U thingy holes, so the nail sits over the extender pipe. Now the construction can't move anywhere and is stiffly attached to your bike. If you have your bricks longer down, you could even manage without the metal U thing, but two nails instead. Be sure to drill your bricks hole for the nail, so the nail rests against the vertical pipe, not allowing the construction to slide backwards.
Step 3: Upper Part, the Notebook Shelf
Now the back rest, the most forward one. It is simply an aluminum holder for your notebook not to slide forward, especially when you brake. It holds to the upper shelf by three screws, all were a few millimeters longer than needed, so I filed them to same level as plywood. But only after I saw some scratches on my notebooks battery. The black part on it is again the sponge like stuff. If you haven't and old CD-ROM drive, then you need to glue some sponge or rubber there. In the middle there is a metal bolt with a nut, which holds a little hook, which in turn holds the rubber rings two in my case for each upper screen corners, I just tied them together to make long enough.. This is necessary, my trial an error testing phase showed, that the notebook can slide-jump-rotate out and decide to move in another direction than you. But I was lucky somehow catching it on the way down almost at pedal level. Not sure how long the rubber rings will hold, but I still have enough of them from old times. They were used to hold together a lot of bus tickets at bus stations.
The third thing for the upper shelf is two metal L shaped things on both sides, to not let the notebook move sideways. I screwed them with two screws each, but it should be sure enough with one screw. I had them with some holes, so I didn't need to drill. I bent a little end of them inwards, so they better hold the notebook. This is a weak part of my design, as it is a bit hard to get the notebook in and out. And they make a little rattle noise when harsh road conditions encountered. That could be remedied by gluing some rubber to them. Will try that at some time.
Step 4: Cable Mount, Vibration Absorber
I lined up two holed metal parts in same direction as bike moves normally, and spaced them 3.5cm from edges of shelves and 15cm from each other. I drilled 4mm holes in plywood all along them. You only need 2 holes at each end2,5cm apart. that makes 4 metal parts (instead you can use 8 pieces small, short ones with only 2 holes each. I bought such, but made my design with long ones anyway) times 2 ends times 2 holes each end and at the end makes 8 holes upper shelf and 8 holes lower shelf.
Now screw the bolts and metal parts together, just to hold it together. All 16 bolts have to go in. Hold one metal part rised and slide the wire rope under it, so it extends on the inside a few cm. Now screw the first two bolts firmly, so the wire is tight. This is the only reason, that will hold the upper shelf right on top of the lower shelf. That's why screws wont do it, you need bolts here. Make sure the wire is 90 degrees to the metal part.
Now comes a bit tricky holding it all where you want moment. Position the upper part over the lower and slide the wire rope same way, but other end from outside to inside over its metal part. This time slide almost all wire through and on the other side over the other metal thing (over metal, under upper shelf, between two bolts). Now connect the other side of both shelves with the rope going from out to inside under the third metal thing, just over the lower shelf, between two bolts. Now the construction gets a bit easier to hold. Be sure to twist the wire, so it rests as freely as possible. The only force acting upon it is the one because it is bent. Next wire it diagonally to the same, lower shelves other corner. Let it go through two bolts again, so it comes out on the right side. Now bend it and connect the upper shelve by wiring through its two screws from right side to inside. Continue the wiring straight out to the left side. The last place to connect, is the lower shelves left, closest to you corner. Do it! Connect it!
Now you have all the necessary wire rope where it should be, with only 2 bolts tight at one end. Adjust the length of the rope by pushing and pulling where necessary, to make both shelves aligned on top. Tighten the bolts in same order as the wire goes from the first two tight bolts. When all 16 bolts tight, you should have your construction as it will be. You shouldn't care about the metal parts bending. The only thing, that matters is that the wire is tightly screwed to the shelves.
I ended up with my shelves spaced apart some 6.5cm