Powerbook 1400c lid rebuild options

[EtherRad]

The PowerBook 1400c lids are notorious for cracking at the hinge as you can see due to the screws on the underside. Is there a way to recreate or fix these? I was trying to redraw on CAD but my skills are not that good. Would 3D scanning be possible? If there is a solid way to remake these and design buttress reinforcement into the plastic surrounding the paired screws I bet there would be a good interest in these. I believe these are ABS plastic.

 

[bibilit]

I will have a try at ABS cement on the underside, pretty solid once done and if you are using the same type of ABS (color, type) it will be more or less invisible.

https://www.matterhackers.com/news/how-to-make-abs-juice-glue-and-slurry

 

[EtherRad]

How could I keep the cracked pieces level while the glue is curing?

 

[Fizzbinn]

Yours isn’t flat when it’s not under stress? 
 

On mine, this post has me thinking about just building up with slurry on the back side as wide and deep as possible. Not sure the space available though...
 

I also need to figure out the best way to oil/losen up the hinges. Seems like the problem has been made worse with time as the hinges stiffen up and put more force on the lid with each close. 

 

[Trash80toHP_Mini]

Our resident chemist confirmed this information:

That link about ABS Slurry is good advice about everything but the chemistry. I forget the exact percentages, but you if you use something on the order of five parts MEK to one part Acetone you'll be much closer to the makeup of commercial ABS Cements. Methyl Ethyl Ketone is the active ingredient of both ABS and PVC cements for chemical welding. It's a more aggressive solvent than Acetone, but Acetone has a lower flash point, IIRC? The combination is obviously better than either alone as that's how both are made for plumbing cements that can be used to make piping for compressed air or liquid at up to 400PSI.

ISTR getting the percentages from the can, MSDS (Safety Sheet) of Oatey brand or from their website? https://www.oatey.com/126494/Category/Oatey-ABS-Cements  You want to be careful about sourcing pure MEK, not a substitute. Apparently it's used for nefarious purposes of some sort? Lowes had Mek Substitute and Home Depot had the real deal the last time I bought it. I'll have to check on what they used to contaminate pure MEK in that substitute if that might be how thy came up with it? Now I'm wondering if it might be Acetone? That'd be just too good to be true. :

I've used dried modeling clay as a negative mold with Olive Oil Spray as the release agent to lay up a really ugly quarter panel of a CRT front bezel with MEK/ABS slurry. Haven't gotten around to experimenting with the Acetone in the mix as yet. Hoping to build a shallow CRT/LCD case or larger parts one day using that method with fiberglass cloth reinforcement as jack leg engineered ABS FRP. Now that I think of it, I should try using that trick one of my several cracked 1400 lids from my stack.

How to hold the "puffed out" plastics in place is a great question. I've got a solution in mind, but it's in the Rube Goldberg class for now. I'll pull out a lid or two and give it some thought.

 

[dcr]

How could I keep the cracked pieces level while the glue is curing?

Can you use tape around the cracked areas to hold it together?

I haven't glued together a PowerBook case but a week or two ago, I had to glue together the plastic casing for an old laminator.  I needed to keep everything straight so it would go back together properly after the glue had dried.  I used tape.  On the outside of the plastic case, I cleaned any excess glue that was coming through the cracks and then taped directly over the cracks.  Went around the cracks and everything I could tape in order to hold it together.  Also, I folded over one edge of every piece of tape to create a pull tab that would make removal easier later.  And that all worked.  The glue dried and I was able to put the laminator back together without any problems.

There is one crack that's not quite even so you can feel it from the outside.  But this is also thicker plastic than a PowerBook case, so I probably would have done better to use stronger tape or, possibly, come up with some kind of metal bracing system to hold it all in place while the glue dried.  But, it needed repair before the cracks got worse, and I didn't have time or the materials available to build a better bracing system.

 

[EtherRad]

Over the weekend I tried a soldering holder clip but way too flimsy. I think the only thing to get it truly non puffed at the crack is to lay a heavy barbell on it while it cures.