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Ampere WS-1: Fixing Plastic Crack?

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fargo

Experienced Member
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Dec 6, 2019
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I've an Ampere WS-1 laptop. The laptop shell is all plastic but the LCD screen has bulky metal hinges! As one would expect, the plastic cracked due to age and the hinges are no longer attached to the body. The picture below shows the base for one of the two hinges. I have to fix this of course, but am not sure how to proceed! I thought of pouring melted plastic in the holes and then reinsert the metal parts. I really would appreciate suggestions here.

IMG_5025.JPG
 
I wish I had something to suggest. Someone here will know what to do. Somehow you have to replace those broken posts that hold the knurled metal part. I don't think pouring molten plastic would work till you fix those posts. It would just break again as there is little holding those together.
 
if it was me i would super glue it back in place.. border off the area around it with modeling clay then fill the area with epoxy. make sure you have screws screwed iinto the standoffs or they will fill with epoxy. Then cut away the clay when done..
 
If it was me I would firstly clean the area and the insert with IPA then glue in with a gap-filling glue. Then use styrene sheet scraps to build the lost part of the insert boss.
Then I would drill sub-millimetre holes in the post flanges at the post circumference and stitch through Kevlar thread, say 10 turns pulled taut, to bind the post and prevent future cracking.
Then secure the thread end with CA and coat the binding with a thin layer of epoxy or the gap-filling glue to seal it.
I guarantee the post would not break again. But hey that's what I'd do.
 
I like the epoxy idea. I'll see if I can source some from a nearby crafts store.
 
I imagine alignment is very important so the superglue to give original positioning is a good idea, then I tend to use an old soldering iron to weld bits back together using some suitable feed material. Melt a V at the crack on one side and fill then do the other side and then smooth off.

Just like any welding, penetration is key (and beware of the fumes, some are deadly).

Epoxy is probably better, but welding is useful when you need to have the same profile.
 
I don't know how many times I have to go through this sort of protocol, but I will do it again.

Remove all of the fractured plastic material. After that position the brass inserts where they should be. Use 24 Hr epoxy resin (called JB weld in the USA or Araladite in the UK). Use a small amount intitially to glue the brass inserts back into position. Try not to get any glue in the threads,

Once that is done, after a say a day, mix up more resin and slowly add it to build up the areas where the missing plastic is/was Don't use too much between each episode of doing it or it will flow away under the influence of gravity.

Once it is done you can apply paint to the surface (mixing it up to the same color as the plastic).

Whatever you do, don't use heat and don't use any solvents that melt the plastic, unless you want a failure to repair on your hands.
 
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I used epoxy on some of these for an old Toshiba laptop that broke one of the hinges around the display. It is ugly on the inside, but it worked.
 
fargo said:
I like the epoxy idea. I'll see if I can source some from a nearby crafts store.
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I use this method alot on apple II repairs. Lots of people stack apple II computers on top of each other or heavy things on an apple II which causes the screw mounts of the keyboard to break off. Epoxy repairs work perfectly and are very strong. And best of all you cannot see the repair as its hidden in the computer.
 
Thank you all for your valuable inputs.

It's not an easy repair. There is no much room around the broken parts to move freely. The metal hinges have weird shape with bulge going between the two plastic studs, so the glue/epoxy/weld must not block the way. And of course, the threads must stay clean to receive the screws.
IMG_5030.JPG

There is a plastic repair video on YouTube using super glue and baking soda. I like this idea as it allows building the missing parts layer by layer, but I'm not sure if the mix will be rigid enough to take the hinges stress.
 
fargo said:
Thank you all for your valuable inputs.

It's not an easy repair. There is no much room around the broken parts to move freely. The metal hinges have weird shape with bulge going between the two plastic studs, so the glue/epoxy/weld must not block the way. And of course, the threads must stay clean to receive the screws.
View attachment 1255755

There is a plastic repair video on YouTube using super glue and baking soda. I like this idea as it allows building the missing parts layer by layer, but I'm not sure if the mix will be rigid enough to take the hinges stress.
Click to expand...
Shelbys' video you shown here doesnt work for repairs under stress so dont bother.
 
I wonder if the failure is symptomatic of the plastic generally degrading. If that's the case (think old 90s Apple gear), any fix will just be a stopgap until something else fails.

Plastic is forever only if it's discarded roadside trash, it seems.
 
VERAULT said:
I use this method alot on apple II repairs. Lots of people stack apple II computers on top of each other or heavy things on an apple II which causes the screw mounts of the keyboard to break off. Epoxy repairs work perfectly and are very strong. And best of all you cannot see the repair as its hidden in the computer.
Click to expand...
What epoxy brand/type you use?
 
Were this my laptop to salvage, I wouldn't leave it to the epoxy to form the final structural bond. It's quite apparent from the photos that the plastic failed from lateral forces. Therefore, the strength of the repair will be a direct result of the strength of the bond between the resin and the remianing plastic.
What I would do is drill some very fine holes (maybe a #70 drill or so) and thread some stainless wire around the brass inserts a few times, so that the insert is firmly locked against the remaining plastic. Then, I'd use epoxy to replace the broken-out bits of case.
 
I believe it's an easy repair. Solutions using glue alone are IMO not enough for parts under stress or tension/expansion, some mechanical component to the fix is required. Binding plus glueing will hold those inserts in very securely and with a low amount of impingement into a working space.

After all a concrete building is rarely just concrete alone but with integrated reinforcement within it.
 
I've used fiberglass cloth to reinforce epoxy with good results. I would also try to fill in as much as the empty space around the damaged area as you can. You might think about doing the same on the other side to prevent it from breaking.

Also, if the hinges are excessively stiff, you might try to loosen them somehow.
 
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