A very much needed improvement...
... And I think you'll agree with me, no? 🙂
Best Answer by vintagepc:
As promised. This is not for the faint of heart, some nimble fingers and technical aptitude are required for success. If you built your printer from kit successfully you're probably in good shape - though the ability to solder is also required here.
Parts:
- Control board with LCD header, SD card, knob. Can buy from LDO or re-use one by removing a broken screen.
- BuyDisplay 5v FFSTN white on black display. ( https://www.buydisplay.com/default/3-3v-5v-20x4-character-lcd-display-module-white-on-black-high-contrast)
- ScotchCal Orange 44 Vinyl film ( https://www.ebay.com/itm/3M-3630-Scotchcal-Orange-44-Translucent-Vinyl-Film-Craft-Sign-DIY-Sheet-Roll/332502701713) Sample size is more than plenty for a couple displays.
Steps: (Note, display looks slightly different, I'm "reconstructing" some of the images as my modified one is already assembled and in my printer)
- Desolder the LCD backlight with desoldering braid or a desoldering tool. (the two pins on the left.)
- Twist the black tabs holding the new LCD frame with a pair of pliers so they align with the holes. (Already done in the above image)
- Gently push the black frame through the holes. Support the LCD with your finger so only the frame comes out. Try not to dislodge the LCD glass from the zebra strips (pink/black in the image below) that connect it to the board, or the strips from the board. They are very sensitive to contamination and alignment. While they can be realigned, it's best to avoid disturbing them if at all possible.
- Carefully work the backlight assembly/panel loose from the through-holes and slide it out form behind the LCD to work on it. (The white bit on the left.)
- Peel off the front diffuser of the backlight panel.
- Cut a piece of orange adhesive film to fit the panel. Best to cut slightly oversize and trim it down later. The sample size has plenty for at least three screens.
- Clean any residue or fingerprints off the front of the panel.
- Carefully apply the orange film, from one side to the other (like vinyl car wrap or phone screen protectors - plenty of YT videos on how to apply those for reference) to minimize bubbles. Smooth down the film and work them out as much as possible.
- Trim film to size
- Reinsert backlight assembly behind LCD and through the holes. Solder it back in place.
- Gently reinstall the black frame over the LCD glass. Push the clips through the holes and twist them to secure it again. You may need to push down a little more once it hits the glass, the zebra strips are typically under slight compression for good contact.
- Install the display on your display board, and install it in your printer! Might be smart to find a way to test it first since it's hard to remove once soldered down. I put it on the pin headers and tilted it slightly so it wedged on the pins and made contact; this let me quickly check that all rows/columns were functional. If they are not, check for missed "clips" or contamination/dirt/alignment issues, especially if the zebra strips came loose during the previous steps.
- Enjoy!
RE: A very much needed improvement...
Hey, I like it! 😀
RE: A very much needed improvement...
I'm very happy how it turned out. I could not easily find LEDs in the red-orange and I wanted in 3020 SMT form (to replace the white ones), so I actually went a different route and replaced the white diffuser film with translucent orange instead. The photo doesn't do it much justice, it looks fantastic in person.
Display is an FFSTN white-on-black 2004; total cost was about $15 with the SD/knob board taken from one with a bad display.
RE: A very much needed improvement...
Maybe this is the solution :
https://www.adafruit.com/product/498
Thomas
RE: A very much needed improvement...
It does look fantastic. And you managed to get the color just right by changing the diffuser, whereas there would be limited color choices with LEDs. (And now I have no choice but to do the VFD mod on my black MK3. 😎 )
RE: A very much needed improvement...
Maybe this is the solution :
https://www.adafruit.com/product/498
Thomas
No, I looked at that as an option but I didn't want the backlight bleed that you see in the images, I wanted as solid black as possible.
It does look fantastic. And you managed to get the color just right by changing the diffuser, whereas there would be limited color choices with LEDs. (And now I have no choice but to do the VFD mod on my black MK3. 😎 )
I apologize for the divot that makes in your wallet 😉 An orange VFD would look just epic, I think.
RE: A very much needed improvement...
Update: I've been asked to make a how-to. I'm currently away from my workshop where my printer is but when I have access again in a bit over a week I will put together a write-up on how I did this, what parts, etc.
Stay tuned!
RE: A very much needed improvement...
Nice with matching orange!
BTW, If one follows the Adafruit link and gets seduced by the OLED black background, don't be.
Our firmware isn't compatible with driving an OLED. If you want maximal contrast ratio, there is another LCD module that has very dark black.
MIDAS MC42005A12W-VNMLW takes some special rewiring, though.
RE: A very much needed improvement...
BTW, If one follows the Adafruit link and gets seduced by the OLED black background, don't be.
Our firmware isn't compatible with driving an OLED. If you want maximal contrast ratio, there is another LCD module that has very dark black.
Fixing the firmware to work with OLED would most likely not be a big issue. The bigger issue is that OLED doesn't have the required longevity, OLED suffers from burn-in severely, and the printer display isn't changing much.
RE: A very much needed improvement...
I used a cheap FFSTN display which has decent contrast; wasn't about to drop $20 on a fancier one given some of the risk since you need to disturb the zebra strips.
RE: A very much needed improvement...
I may have mentioned it already, but I've got a VATN ("true black") Powertip NPC2004WRP LCD in my printer now. And since my printer doesn't have orange parts, I didn't bother with the color change from white. A (green) Noritake Itron CU20045-UW5J is now on the way to me. I'll post photos once installed.
RE: A very much needed improvement...
I may have mentioned it already, but I've got a VATN ("true black") Powertip NPC2004WRP LCD in my printer now. And since my printer doesn't have orange parts, I didn't bother with the color change from white. A (green) Noritake Itron CU20045-UW5J is now on the way to me. I'll post photos once installed.
Where did you find the display? I've been looking at doing this for a while, but prices at digikey, mouser, and the like seem to be in the $75-$85 range.
Makes me wish I'd have snatched them up on eBay back when someone had them for ~ $45 each.
RE: A very much needed improvement...
The Midas VATN is 17 pounds at Farnell. https://uk.farnell.com/midas/mc42005a12w-vnmlw/lcd-alpha-num-20-x-4-white/dp/2483356
Just wire it correctly as in last post of the "smoking" LCD thread. VATN's really do have nearly black backgrounds...
RE: A very much needed improvement...
Unfortunately the Midas VA-TN ones seem to be stupid expensive on this side of the pond ($50+)... they only seem to be sold from UK distributors, shipping will be killer. That's one of the reasons I went for FFSTN instead.
RE: A very much needed improvement...
Ouch! That's what I just paid for two more units including shipping. (from Newark, Farnell's US branch)
RE: A very much needed improvement...
Where did you find the display? I've been looking at doing this for a while, but prices at digikey, mouser, and the like seem to be in the $75-$85 range.
Makes me wish I'd have snatched them up on eBay back when someone had them for ~ $45 each.
The links in my post point to TME, which sells the VATN's for about 17 USD. That's within Europe, of course.
RE: A very much needed improvement...
Where did you find the display? I've been looking at doing this for a while, but prices at digikey, mouser, and the like seem to be in the $75-$85 range.
Makes me wish I'd have snatched them up on eBay back when someone had them for ~ $45 each.
The links in my post point to TME, which sells the VATN's for about 17 USD. That's within Europe, of course.
I was curious about the VFD, not the LCD. 😉 I see you linked to TME for that as well, so I suppose that's the answer. Here in the USA they can be had from Digikey and Mouser, at what appears to be similar prices as TME.
Scott
RE: A very much needed improvement...
I was curious about the VFD, not the LCD. 😉 I see you linked to TME for that as well, so I suppose that's the answer. Here in the USA they can be had from Digikey and Mouser, at what appears to be similar prices as TME.
The VFDs are awfully expensive everywhere. But that's basically because the production is much harder than for any kind of LCD. And there is no guarantee I won't hit compatibility issues like others did with OLEDs. After all, it's a different controller that's just trying to be compatible with HD44780. They can still be found cheaper on eBay, but usually not in the HD44780-compatible variety.
RE: A very much needed improvement...
Just ordered a MIDAS VATN, should be with me in a week, always hated the cheap existing display, the polarising filter doesn't even sit flat inside!
Seeing how my printer is black and white, this will be just right.
Thanks for the information.
Normal people believe that if it ain’t broke, don’t fix it. Engineers believe that if it ain’t broke, it doesn’t have enough features yet.
RE: A very much needed improvement...
Chocki, just to be clear.
Do NOT hook up all the pins of the MIDAS VATN to the controller board. Holes 3 and 15 must NOT be connected to the controller board. Leave 3 and 15 without header pins. Instead, bridge 3 and 15 with a 9.8K resistor to set contrast. Hole #1 is rightmost in this picture.
vintagepc, Does the LCD unit you installed use all 16 pins just like the stock LCD module?