PowerBook 540c Restoration Project

[jmacz]

there are a lot of PowerBook 190 and 5300 owners right now that are looking for someone to design a hinge fix part for them, myself included. One you're done with this project, maybe look out for one of those as your next!

Those grayscale / black-n-white ones freak me out with the posts about the tunnel vision issue.

 

[3lectr1cPPC]

Yeah there's a lot of confusion going on it seems on which systems are and aren't affected. It's only active matrix mono/grayscale panels made by Hosiden. The only PowerBooks that have them are the 170, 180, Duo 250, Duo 280, and the 540. None of the 190/5300 models had an active matrix grayscale model. The 190 and 5300 base units (not the 190cs/5300cs/5300c/5300ce) are grayscale, but they use passive matrix screens made by Sharp or Casio. Not affected, though many of the screens used in that series do need caps replaced.
I've got a comprehensive page on tunnel vision on my website: https://macdat.net/important_issues/tunnel_vision.html

 

[jmacz]

Yeah there's a lot of confusion going on it seems on which systems are and aren't affected. It's only active matrix mono/grayscale panels made by Hosiden. The only PowerBooks that have them are the 170, 180, Duo 250, Duo 280, and the 540. None of the 190/5300 models had an active matrix grayscale model. The 190 and 5300 base units (not the 190cs/5300cs/5300c/5300ce) are grayscale, but they use passive matrix screens made by Sharp or Casio. Not affected, though many of the screens used in that series do need caps replaced.
I've got a comprehensive page on tunnel vision on my website: https://macdat.net/important_issues/tunnel_vision.html

Wow, lot‘s of great info there. Thanks!

Ok, well maybe I will think about it. I have to finish this 540c, potentially do a battery rebuild for it, and then I still have my Spectrum 24/III that I have to fix.

The 190 and the 5300 have the same body and hinge layout physically? So a fix for one can work on the other?

 

[3lectr1cPPC]

The 190 and 5300 grayscale models will likely need a custom part done for them, as their rear housing is thinner than the color models I believe. Otherwise, the 190cs/5300cs/5300c/5300ce models should all be able to use the same part.

And I'm glad that page was helpful for you!

 

[jmacz]

The 190 and 5300 grayscale models will likely need a custom part done for them, as their rear housing is thinner than the color models I believe. Otherwise, the 190cs/5300cs/5300c/5300ce models should all be able to use the same part.

Which one do you have and need the part for? The grayscale or the color?

Never got into the PowerPC Macintoshes and don’t plan to. But will keep an eye out for a 190 or a 190cs.

 

[3lectr1cPPC]

The color models at the moment. The odd thing about their design is that they do have two standoffs for each hinge, but for each hinge, one standoff is on the rear housing and one is on the front. So you’d probably have to make multiple parts to make it work.

 

[jmacz]

The color models at the moment. The odd thing about their design is that they do have two standoffs for each hinge, but for each hinge, one standoff is on the rear housing and one is on the front. So you’d probably have to make multiple parts to make it work.

Ok, will keep an eye open for a 190cs then.

Not sure why I have zero interest in the PowerPCs but maybe I need to try it. Maybe it’s more a distaste for MacOS 8+ in which case I can run 7.5.5.

 

[3lectr1cPPC]

What experience with the PPC macs do you have? Many of the early ones were quite slow, so if you were running OS 8 on say, a PowerBook 5300 or a Performa 6300, especially a stock one, will not feel great. Running faster 603ev or 604 hardware though is pretty nice in my opinion. The PowerBook 3400 and the higher end 1400s are both pretty zippy, and any pre-g3 mac can run at least 7.6.1, and many can run earlier too.

 

[jmacz]

What experience with the PPC macs do you have? Many of the early ones were quite slow, so if you were running OS 8 on say, a PowerBook 5300 or a Performa 6300, especially a stock one, will not feel great. Running faster 603ev or 604 hardware though is pretty nice in my opinion. The PowerBook 3400 and the higher end 1400s are both pretty zippy, and any pre-g3 mac can run at least 7.6.1, and many can run earlier too.

Zero. I moved over to Linux around the time PowerPC-based Macs started to become available. And when MacOS 8 came out, it just wasn't very appealing to me. So really never got into it. I have a soft spot for System 6/7 and earlier, as well as 68K. Nothing really for the generation after that. Maybe picking up a 5300c/cs running System 7 might bridge that for me.

 

[3lectr1cPPC]

Now I'm no hater of the 5300 series, but I do have to say that they aren't the best introduction to PowerPC. They're pretty slow (even on System 7) as they have no L2 cache onboard. They're perfectly fine systems in their own right, but I'd level your expectations if you're picking one up.

The 190s on the other hand are quite interesting systems, and in my opinion far underrated. The 190cs specifically. They're the same speed as the much-loved 540c, but you can get one a lot cheaper. They've also got PCMCIA built in, which is very convenient for file transfer. The screens are worse as they're passive matrix, BUT, you can swap the LCD and cable over from a 5300c and get yourself an active matrix one. That makes it as good or better than a 540c. At that point which is better just comes down to which design you prefer really.

 

[jmacz]

If I'm correct and the original screws are M2.5, then my design's ability to incorporate an M2.5 threaded insert should allow you to reuse the original screws.

But unless my 540c is different from yours, the original laptop didn't have brass inserts for the lid. It does have brass inserts in the body but not in the lid. Take for example this picture:

Ok so my final guess was right... the chassis screws (and many others) are indeed M2.5s and a few M2s.

BUT, I was wrong about the hinges. Apple is using some coarse thread screws for the hinge to lid screws (pictured below). I confused myself yesterday as I was working on that magnesium frame and was looking at the chassis screws, not the hinge screws.



Designed for plastic. That's why the lid doesn't have brass inserts, because they are using these screws. That also explains why the other existing 3d print designs had such tiny holes (ie. to continue using these screws above). Given the new 3d printed parts are thicker, I'm sure it will work fine. But, I'm going to go with M2.5s and the brass inserts instead.

I received the M2.5 x 6mm brass inserts today and they fit into my 3d printed parts well. So I'm going to go with this so I don't have to worry about stripping and I think they'll be a little bit stronger.



When I share the final STL files later, I will include 3 different models: 1.) Original one piece design but with larger holes to accommodate a brass insert (for those wanting to use M2.5 screws instead). 2.) Two-piece design with holes for the brass inserts. 3.) Two-piece design with holes for the stock screws.

 

[3lectr1cPPC]

Ah very interesting. And man what a poor design from Apple. I thought they were bad like most other 90s laptops - thin plastic around a brass insert, with no structuring around to keep them intact. But nope, even worse.
Those STL files are going to be lovely!

 

[joshc]

And man what a poor design from Apple. I thought they were bad like most other 90s laptops - thin plastic around a brass insert, with no structuring around to keep them intact. But nope, even worse.

Not surprising though - Apple cut a lot of corners in the 90s... not sure that this would've saved them heaps of money, but there was probably a reason they did it. If you look at a lot of the plastics Apple was putting out throughout the 90s, they just weren't designed to hold up probably for longer than 3-5 years, a typical lifetime of a machine in commercial use, and they certainly wouldn't have been designing anything in mind for 20-30+ year use.

 

[3lectr1cPPC]

I don’t think it was just apple using terrible plastic, it was just that plastic of the time just doesn’t hold up. Without fail, every single 90s PC laptop I have is also a brittle mess.

 

[joshc]

I don’t think it was just apple using terrible plastic, it was just that plastic of the time just doesn’t hold up. Without fail, every single 90s PC laptop I have is also a brittle mess.

Yes and no. Look at the plastics Apple were using in the 80s, which is also ABS, same stuff as used later on, but the quality and the design of the plastic parts is vastly different. I think two things happened. Apple cheapened the design of the parts, but also probably started using cheaper suppliers. But the design is really crucial - look at the lid of the IIci/IIcx/Quadra 700 case if you want to see an example of Apple spending millions of dollars perfecting a piece of plastic, that lid is really really strong because of how it was designed. They stopped doing that sort of thing in the 90s, and that wasn't to do with 'terrible plastic' - that was to do with using cheaper designs.

 

[3lectr1cPPC]

Well, build quality was certainly part of it, but the plastic quality is the largest factor I'd say. Those PowerBook hinges weren't failing when they were new, at least, they weren't very often. Plus, there are plenty of laptops with great build quality (like Toshibas) that are still falling apart because of the terrible plastics of the time.

 

[joshc]

That was my point though - the design wasn't catered to them being used for a long period of time, so of course they didn't fail when new. Plastic also gets weaker with time, but that can be counteracted by the design. But Apple don't build laptops to last 30 years, nobody does. But saying 'plastic of the time just doesn’t hold up.' isn't quite true - hence my reference to the plastics Apple was using back in the 80s, and the fact the 90s plastic is not really that different, but the designs used are.

 

[3lectr1cPPC]

I'm gonna have to disagree with you in part here. I agree first off, that good design can make up for bad plastics. Toshiba's hinges for example on many of their laptops are still holding up well, but other parts aren't. Like my Tecra 500CDT, which is full of broken clips and has a big old crack on the palmrest. The hinges are intact though, and feel strong.

On the other hand though, the plastics are worse. You pretty much never hear of a PowerBook 100 with a hinge failure. Some of this is down to Sony's good design, but that laptop is still full of plastic standoffs, yet you don't hear of them cracking and falling apart on their own like you do for the other Apple-designed 100 series laptops. How many times have you opened up a 100 series PowerBook to then see standoffs holding in the drive cages and motherboard be broken with next to no stress put on them? That isn't bad design, that's brittle plastics. The 100 on the other hand was one of the last to have better plastics quality. On the other hand, designing the high-stress hinge mounts to rely on those same standoffs is bad design.

Even many of IBM's laptops, legendary for their excellent build quality, are having hinge issues now. The best of the best aren't, but just about everything else is.

Another example would be my Latitude CPi and CS laptops. They both have their fair share of poor design, like thin plastic vents on the Latitude CS with tiny clips, and the hinge mounts on the CPi. It makes sense for those to break. But on the other hand, I've had standoffs and plastic fall out everywhere just taking them apart. I had to take apart the Latitude CS to replace the speaker which was blown, and so many screw mounts snapped right off. That's just bad plastics.

Part of it is likely using thinner parts where structural support is needed, like display housings and CRT mounts on say, an LC 575. 80s systems didn't do that. But another part of it is that the plastic quality clearly got worse, and that can't be ignored.

And yes, obviously they weren't meant to last 30 years. But there was still clearly a downturn.

 

[jmacz]

Hinges

The parts did work. Feels sturdy. I am not going to go out of my way to overly stress it of course just in case, but it felt pretty sturdy to me.

I will attach the STL files to this post for the following models:

• One Piece Support for Inserts - this is the STL file for a single piece bracket which has holes for brass inserts instead of screws. I am not including a model for screws. You can grab the existing screw-based models from Thingiverse.
• Two Piece Support Left for Inserts - this is the STL file for a two piece bracket which has holes for brass inserts instead of screws. This is the left one when you're facing the screen.
• Two Piece Support Right for Inserts - this is the STL file for a two piece bracket which has holes for brass inserts instead of screws. This is the right one when you're facing the screen.
• Two Piece Support Left for Screws - this is the STL file for a two piece bracket which has holes for screws. This is the left one when you're facing the screen.
• Two Piece Support Right for Screws - this is the STL file for a two piece bracket which has holes for screws. This is the right one when you're facing the screen.

For the screw versions, use your original screws. For the brass insert version, you will want to purchase brass inserts for M2.5 screws, and the size you want is 6mm deep by 4mm outside diameter. And then obviously use M2.5 screws (8mm length). You should be able to find these on Amazon.

M2/M2.5/M3 Brass Insert Set: https://www.amazon.com/dp/B09MK3VCYC
M2.5 Button Head Screws: https://www.amazon.com/dp/B09CPDVYB7

Note that you might check to see if you can find different screws. The ones linked above have a 1.5mm hex socket which is pretty small. A little bit bigger (2mm?) might be easier to deal with but I couldn't find a good set.

For assembly, I first used a soldering iron to press in the brass inserts into the brackets. Then I epoxied the brackets onto the lid and waited 24 hours.

 

[jmacz]

Current Status

I ran into a slight problem with the display. I recapped the motherboard, modem card, inverter board, and the LCD. I must have messed up something along the way as I'm testing out everything and I cannot get a picture on the display.

• The 540c is booting - it chimed and I can hear it beep upon startup because it's showing the dialog box that says I did not cleanly shutdown the system. So that suggests the motherboard recap is fine (it was just the one cap).
• The speakers work - again, heard the chime and the beep later in the boot process. This means the cable between the motherboard that goes up around the right display hinge is connected and working.
• The ribbon cable between the display and bezel board is securely connected.
• The ribbon cable between the motherboard and bezel board is securely connected - again, the speakers work so this should be ok.
• The ribbon cable between the speakers and the bezel board is securely connected - again, the speakers work so this should be ok.
• The power cable between the inverter and backlight is securely connected - but I am seeing zero volts across the terminals while the machine is powered on. The backlight is not turning on.
• The ribbon cable between the bezel board and the inverter board is securely connected.

I tried removing the 6.3V 220uF on the inverter and replacing it with another 10V 220uF and that didn't help (I didn't have another 6.3V to try but 10V should be fine since it's a higher voltage). I did not replace any of the three purple caps on the inverter board.

I checked each tantalum to ensure the specs are correct, polarity is correct, it's securely on, has proper connectivity to the board and traces. Those all look good.

Next, going to go through each pin on the two ribbon cables (display to bezel, bezel to inverter) and see if any of them got messed up. Then will test board to board with the ribbon connected.

I would think the backlight should have power when the laptop is powered up but it doesn't. Not sure what drives power to the backlight connector on the inverter board but will have to trace through that.