PowerBook 180 tunnel bake aftermath

[Sideburn]

Hey all,

So I just did the 8 hour lcd panel bake to fix the tunneling issue with the PowerBook 180 and all is good EXCEPT I just noticed that one vertical row of pixels is duplicate itself two pixels over. I’m not sure if I have introduced this problem or if it already existing and I never noticed.

Here’s an example of the issue. I made a single pixel vertical line in photoshop and when I move the line horizontally to the right spot the line doubles and it’s white value splits in half:

Here’s the single line:



After moving it to the left onto the faulty line it doubles (you can also see the duplicate line i the scroll bar):



I’m afraid to muck with the display more and make things worse. Would this be related to the lcd baking and then re-mounting it onto the PCB? Is it an alignment issue? Or do you think this was pre-existing ?

 

[Sideburn]

Update!
I fixed it. The screen is finally perfect. What a nightmare and a learning experience. It got so bad the were dead vertical and horizontal lines everywhere and I could it get it back in order. I almost threw in the towel. Then tried cleaning the traces where the zebra strives touch and that leaked into the backlight sheet and oh my got it was terrible.

I must have removed and replaced the lcd a dozen times for hours.

The CRUCIAL part is the alignment of the LCD glass on the crosshairs on the PCB. And you don’t do this be aligning the frame. You move the glass within the frame. What worked best for me is to just slightly drop the the PCB on its sides while the frame is loosely fastened down. If you get it spot on then you don’t even need that much tightness clamping the frame down.

My error was thinking it wasn’t tight enough down because of you press harder it would fix it. But that’s not the solution. It’s the alignment!

Lessons learned. Now I may revisit my Macintosh portable lcd displays.

 

[croissantking]

So I just did the 8 hour lcd panel bake to fix the tunneling issue with the PowerBook 180 and all is good EXCEPT I just noticed that one vertical row of pixels is duplicate itself two pixels over. I’m not sure if I have introduced this problem or if it already existing and I never noticed.

Well done on your success. Which guide did you follow or what steps did you take for the bake? I am tempted to try this on mine. Hope I don’t ruin the oven for cooking…

 

[Sideburn]

Well done on your success. Which guide did you follow or what steps did you take for the bake? I am tempted to try this on mine. Hope I don’t ruin the oven for cooking…

No guide. Just what I’ve found online and YouTube of what others have done.

I did 175 (180) degrees Fahrenheit for 8 hours.
Some do up to 220.
I used a temperature probe to check actual since my oven apparently runs hotter and only has 175 or 200 as a setting i stuck with 175 and the probe measured 180

One more thing in the lcd glass. It is stuck to the frame with tape initially so it should be aligned already. Mine came off the frame and that’s why I had all the problem getting it aligned back.

The baking seems to work well. At least so far. I left the monitor on for at least two hours and no tunnel effect.

 

[imactheknife]

Awesome, might try this on my 180.. love the display, but would hate to ruin it too. My 170’s dont tunnel thank goodness

 

[Sideburn]

Should be fine. If it can take the 4 hours of abuse I gave it then there shouldn’t be a problem. Just go slow and be careful not to let the glass delaminate from the frame or then you have to go go through the alignment prrocess.

 

[croissantking]

I’m definitely going to try. Nothing much to lose as it’s pretty much unusable as is. I probably need to deep clean my oven first, or the display will come out stinking of oil and fat

 

[joshc]

I probably need to deep clean my oven first, or the display will come out stinking of oil and fat

And afterwards as well, at the very least a run for an hour at the highest temperature it'll run at, to get rid of any fumes from baking the display before you use it for food again.

 

[croissantking]

Here goes. I’m going to bake it at 175F (82C) for 6 hours and see what happens.

 

[imactheknife]

Interested to see if this works. I have a powerbook 180 with this nasty tunnel vision after 1/2 hour

 

[croissantking]

So I went to 90C (194F) for 6 hours in the end.

Here’s before, after running for one hour exactly:



And after.


There is some crazing/cracking that wasn’t there before, across the whole display. It’s not super obvious.


I’ll try another round. Thinking 100C for 5 hours.

Also, I’ve got the alignment problem. I was very careful to keep the LCD adhered to the metal frame and I think it still is. But the crosshairs don’t align. Not sure what happened there.

 

[croissantking]

So I did a 100C (212F) bake for 4 hours.

Here’s the effect after an hour of runtime.



Pretty big improvement, right?

I’d call it a win, but for the following:



The corners are delaminating. In addition to the crazing I showed previously, it looks fairly ugly. You only see it really when the display catches the light from a certain angle and the display is for all intents and purposes more usable than before, but… yeah. Not super happy with the outcome.

 

[Sideburn]

Bummer. Mine worked out almost perfectly UNTIL I kept tinkering with it and eventually ruined the upper 20 horizontal rows by breaking traces on the board. The baking completely fixed the tunneling but I had a couple lines at the very top that were missing so I kept mucking around with it and then a couple clamp down metal tabs broke and then the downward spiral began…

I ended up replacing it by buying another scrap broken PB180. And amazingly got lucky and this LCD has no tunneling at all! Aside from a single dead pixel it’s perfect.

 

[imactheknife]

Bummer. Mine worked out almost perfectly UNTIL I kept tinkering with it and eventually ruined the upper 20 horizontal rows by breaking traces on the board. The baking completely fixed the tunneling but I had a couple lines at the very top that were missing so I kept mucking around with it and then a couple clamp down metal tabs broke and then the downward spiral began…

I ended up replacing it by buying another scrap broken PB180. And amazingly got lucky and this LCD has no tunneling at all! Aside from a single dead pixel it’s perfect.

Yeah thats great you found a good lcd! My big fear is ruining my pb180 display. Both my power book 170’s are perfect with no tunnel vision so not going to screw up the 180 if i want to play with an 030 laptop. It is beautiful until 1/2 hour of running then tunnel vision creeps in

 

[bigmessowires]

What's the theory behind baking to fix the tunneling? Is it supposed to get rid of moisture or something like that?

 

[croissantking]

What's the theory behind baking to fix the tunneling? Is it supposed to get rid of moisture or something like that?

Nobody is really sure. Some say it’s moisture, while others say it’s to do with readhering the LCD’s layers.

 

[croissantking]

I ended up replacing it by buying another scrap broken PB180. And amazingly got lucky and this LCD has no tunneling at all! Aside from a single dead pixel it’s perfect.

You are very lucky indeed. My aim was to have a fully working 180, but I’ve given up on this after my failed baking attempt, and decided I’m happy running a passive matrix screen. They are not so bad anyway - actually they have better contrast than the active matrix panels.

Yeah thats great you found a good lcd! My big fear is ruining my pb180 display. Both my power book 170’s are perfect with no tunnel vision so not going to screw up the 180 if i want to play with an 030 laptop. It is beautiful until 1/2 hour of running then tunnel vision creeps in

Yeah, I’d bake it only if you have nothing else to lose. Perhaps you can pick up another 180 to experiment with.

Your 170s are also 030s, btw

 

[Sideburn]

Yeah I bought a whole other on 180 and between the two have made a pretty mint machine. I’ve put a BlueSCSI in it and too. Two ram cards and transplanted ram from one to the other and maxxed out the ram and then I built a new battery pack for it. Now with the Wi-Fi BlueSCSI it gets online too so downloading software and installing it is a breeze.

 

[croissantking]

I am thinking about replacing the layers of sticky polarizing film on the 180's LCD as is being discussed here: https://68kmla.org/bb/index.php?thr...book-145b-screen-polarizer.40533/#post-508082

Meanwhile, I bought another 180 off eBay for a good price, so I'll have another screen to play with. This will be my 5th 100-series PowerBook purchase.

 

[3lectr1cPPC]

This will be my 5th 100-series PowerBook purchase.

And then before long you'll be at your tenth. Then twentieth. Then before you know it, your home will be full of them.