Ceci est une ancienne révision du document !
In issue #62, we looked at the software side of creating the Tweet Screen, this month we look at the hardware side. WARNING - this will definitely void your notebook’s warranty! Before starting, a few words on some of the objectives: • keep the cost down • use only available tools and materials if possible • it has to be stable and sturdy
Materials: IBM Thinkpad R31 (when I wrote this I saw a R31 for £40 on ebay.co.uk) • Lenovo 3000 C100 notebook (approximately £38 - see below) • Black 11” x 14” frame (approximately £9.51 from an art store) with 1 inch depth • Electrical tape
Tools: • small technician's screwdriver set • junior hacksaw • dremel • round and square files • grounding strap • safety glasses
Just after issue #62, I ran into video issues with the Thinkpad R31. Since I’d already pre-tested Tweet Screen on my own aging notebook, a Lenovo 3000 C100, and I found it several times on ebay with better specifications for less money than the Thinkpad R31. I used the 3000 as the basis for part 2 of our Tweet Screen article.
The Lenovo 3000 C100 comes in 2 models, one with a Celeron 1.5GHz CPU and Broadcom wireless chipset, and one with a Pentium 4 1.7GHz CPU and Intel wireless chipset. The model used in this article is the Celeron-based model. Both models have identical 15” LCD screens.
In part one of this article, we covered the software side of setting up the Tweet Screen. In part two, we’ll cover disassembling and installation of the notebook in an 11” x 14” picture frame. I found the picture frame after visiting a couple of art stores. Having created a notebook picture frame several years ago, I knew it was important to have as much depth as possible to hold the notebook. Most art stores had frames with more than 1 inch depth, but the glass was often set almost at the back of the frame, rendering it useless. The frame I chose was 1 inch thick with the glass a few millimeters from the front.
A number of years ago when I built the notebook picture frame, I made a couple of related mistakes: 1) I didn’t buy/build a frame big enough to hold the components of the notebook. 2) In further attempting to reduce the amount of parts in the notebook, I did not test the notebook enough during the second disassembly process.
This time, before disassembly, the notebook stuck out about ¼” inch. This time I tested often and decided not to attempt to remove everything from the notebook, keeping the disassembly as simple as possible. Additionally, I installed SSH, set up the notebook’s wireless, and gave the notebook’s wireless a DHCP reservation on our router in case I needed to remotely shut down the machine (which turned out to be a great step).
Ideally, disassembly should be done on an anti-static mat. I didn’t have one handy so I used an anti-static strap connected to a metal ground. I had a large motherboard anti-static bag handy, but since I only ever exposed the screen and the front bezel above the notebook keyboard, it really wasn’t necessary.
Disassembly started with taking out the battery and DVD-RW, then testing to make sure the notebook powered on. The Lenovo 3000 C100 has a slide switch that conveniently pops out the battery. Removing the battery eliminates heat and lessens the weight of the entire unit. The DVD-RW is held in by a small, F3, single screw.
Most of the screws on the bottom of the unit are either of the F3 (short type used to secure the memory lid, hard drive, screen, and DVD-RW). or F6 (longer type used to keep the case together). Only two other longer screws securing the screen base to the notebook were removed at a later stage. I kept the screws organized on a couple of long stickers marked F6 and F3, and later deposited these in an inexpensive plastic sorting box I bought at a dollar store.
Next, I bent the screen backwards so it was almost level with the notebook. The plastic bezel on the front of the notebook (where the buttons and LEDs are) is a long strip of plastic, about an inch thick, and can be removed by prying up the left side and gently pulling up the rest of the strip. I used the small slot head of the notebook screwdriver to do this. With the bezel off, I marked around the power switch using a felt marker.
At this point I tested the notebook using the plastic end of the screwdriver to power on the unit. Because the unit boots right to the Visible Tweets screen, each time I shut down I needed to hit the F11 key to show the Chromium browser minimize/maximize/close buttons (alternatively, I could have probably just hit Ctrl+Alt+Del to bring up the shutdown menu, but I did things the hard way).
The next job was to remove the casing from the screen. While this is one of the thinnest parts of the notebook, the latch at the top which secures the screen to the notebook when closed would make it impossible to lie the screen flat on the glass. Most laptops have stiff round plastic covering a number of screws. In the case of the 3000 C100, there were 6 small F3 screws hiding behind the plastic cylinders. I used the smallest slot head to pry up the plastic cylinders then used a small Phillips screwdriver to remove the screws.
After removing the front panel plastic from the screen, I noticed a couple more screws securing the wireless antennas to the top of the screen. At the bottom of the screen lay the screen inverter. I carefully removed the tape securing the inverter to the back of the case, then unscrewed the antennas and removed the plastic LCD backing.
Removing the backing reveals that the LCD is secured to the notebook by a couple of thin metal rods with several small screws on each side. These rods are secured to the base of the notebook by a couple of long screws. Initially I removed these screws, but found working with the screen unmanageable, so I secured them back in until I removed the screws securing the LCD to the rods.
Just after removing the back plastic portion of the LCD case, look at the back of the LCD. On the back of the Lenovo 3000 C100 screen is tape cautioning not to touch the backlight portion near the top of the LCD. Of course I had already touched it without realizing, so at this point I powered on the notebook and tested again - thankfully it booted. Note that the backlight electronics were covered by a thin film of plastic, but they might not be on all notebooks.
With the screen detached from the metal rods, the next job was to secure it on the back/bottom of the notebook. But before attaching the screen, I peeled a thin film of tinfoil-like metal off the back plastic LCD panel. This metal film acts as an anti-static shield. I carefully removed the metal foil and attached it to the bottom of the notebook, taking care to cut out a small square to vent the memory area. Much of the stickiness of the foil had stuck to the back plastic panel no longer in use, so I used electrical tape to secure the foil to the bottom. I also used electrical tape to secure the screen to the plastic base of the notebook, taking care not to cover too much of the screen or leave metal exposed.
With the screen on the opposite side of the keyboard I now tested the unit once again. This time shutting the unit down via keyboard and trackpad proved quite difficult, even with a mirror. Happily I had already set up a static DHCP reservation for the machine, and installed SSH so I remotely shut it down over SSH.
sudo /sbin/shutdown -h now
At this point, I had a bit of the inverter wire inconveniently placed at the top. Normally this wire is channeled into the LCD screen, but it proved to be quite helpful in the end adding a few extra millimeters so that the top and bottom fit snugly inside the picture frame. This left a gap just shy of 1 centimeter on each side of the frame.
With the notebook in the frame I marked off an area of ventilation at the bottom and the area the power core was to plug into the system. With this done I removed the notebook and cut out the marked off areas. I’d love to claim that I did this expertly, but the truth is I used what I had at my disposal, a junior hacksaw and a dremel.
To smooth out the roughness left by my cutting I used a couple of files to file down the cut out areas so they were nice and smooth. Surprisingly, it turned out well enough that I was able to reuse the wood block from the ventilation cut out. This block I cut in half and filed down. I put one of each block in the 1 centimeter gap between the notebook and frame. These small blocks kept the notebook from moving within the frame.
At this point the Tweetscreen was finished, it could stand on its own without falling out the back. It was time to fire it up again for one last shot.
With a bit more time I would have filled in the sides and used a wooden bracket to secure the system further. I also would have rigged up a button on the side so I wouldn’t have to power the system on from the back. As the Tweet screen sits now it works well, and could be hung except for the power button detail. Set on a desk it looks great and feeds us all the tweets about refurbishing, Kwartzlab, and different Ubuntu topics.
Next month, a look at our local Hacker Space Kwartzlab. Kwartzlab is the host of a number of interesting projects from the original Twitter screen I mentioned in Issue 62 to hosting Ubuntu code and bug sprints.