Psion Series 3a Hinge Repair

Hinge and clamshell repair for the Psion Series 3a. The same case is used by the Psion Series 3, Psion Series 3c and Psion Series 3mx, so this procedure applies to all four — see Model differences at the end.

The 3a clamshell. Two visible hinges sit just beyond each end of the button bar; two more are hidden between the battery compartment and the bar. All four break, and all four can be repaired.

Hinge breakage is one of the three classic Series 3 failures, alongside the button bar and the screen cable. In period it meant returning the machine to Psion or a dealer at considerable cost; today it is a bench job.

The four hinges

There are at least four hinge points:

Hinge locations and failure modes

Hinge	Where	Construction	How it fails
Two visible hinges	Just beyond either end of the button bar	A moulded hinge with a metal rod down the centre	The 8 mm-wide neck connecting the hinge to the lid shears off, about 2 mm above the hinge proper
Two hidden hinges	Between the battery compartment and the button bar	Plastic nipples that locate into plastic holes	The nipple breaks off

Symptoms. A broken hidden hinge makes the back of the machine look crooked while opening, and leaves the button bar flexing out. A broken visible hinge leaves the lid loose or detached on that side.

Cause. The visible-hinge failure is attributed to over-opening the lid, which bends the metal pin in the hinge and puts torque on the narrow neck. That is worth knowing because it is entirely preventable — see Psion Series 3a General Maintenance.

⚠️ Before you start

• Back up to an SSD or a PC first. The procedure separates the two halves of the machine and removes both batteries; anything in RAM will be lost.
• Remove the main AA cells and the CR1620 backup cell.
• Observe anti-static precautions.
• Do not force the LCD. The panel and its ribbon are the parts you cannot replace.
• Work over a tray. There are small metal pins and a pair of springs in this machine that will not be found again if they escape.

Route 1: repair the broken hinge in place

This is the quick route, and both variants are reported as holding up in service.

Visible hinge — sheared neck

1. Recover the broken-off piece. It is usually still inside the case.
2. Degrease both faces with isopropyl alcohol.
3. Bond with epoxy (Araldite or similar). Two approaches are documented and both worked:
   • Epoxy plus a thin strip of steel bridging the joint, which reinforces the narrow neck.
   • A plain blob of epoxy with no reinforcement.
4. Clamp lightly and leave it to cure fully — the full cure, not the handling time.
5. Do not over-open the lid afterwards. The repair is stronger than nothing, not stronger than the original.

A third documented approach used paperclips, solder and pins to build a replacement, though the write-up is no longer online.

Hidden hinge — broken nipple

The nipple is a plastic peg in a plastic hole. Once broken there is nothing to bond to on the peg side, so the practical options are to bond a replacement peg (a short length of plastic rod or a trimmed panel pin bedded in epoxy) into the original location, or to move to Route 2 and fit a donor lid.

Route 2: separate the halves and fit a donor lid

This is the thorough route: it swaps a good lid onto your machine, and it is also the route you take to reach the screen ribbon cable.

Getting into the machine

Follow the standard 3a teardown as far as removing the mainboard:

1. Remove the main and backup batteries.
2. Remove the four case screws from the base.
3. Lift the battery cable over its catch, then pull the plastic battery connector off the mainboard by its edges.
4. Open SSD slot B and remove the screw inside it.
5. Open SSD slot A and remove the screw inside it. This one is usually under the warranty label.
6. Working one side at a time, lift the keyboard cover from the bottom case. Inserting a small screwdriver into the vacated SSD screw holes pushes the cover up far enough to get fingers under it.
7. Pull the keyboard cover forward and up so the small plastic tab comes out from under the hinge. Repeat on the other side.
8. Release the top tabs with a small flat screwdriver working underneath the button bar — the bar bows outward under spring pressure at this point.
9. Release the two remaining tabs on the lower part of the keyboard cover. Removing the rubber keyboard membrane and keys first makes this easier. There are two types of keyboard: one with the keys stuck to the membrane and one without, so lift carefully until you know which you have.
10. Lift the mainboard by inserting a small screwdriver into the slot at the front, using as little pressure as possible — the plastic rim damages easily. Then push the 3Link plastic shutter in and lift the board out.

Separating the lid

1. Remove the button bar ribbon cable. Push up the edges of the connector, then pull the ribbon out gently. On a 3a this cable is blue.
2. Remove the button bar: push one side of the bar so the small plastic hinge next to the battery housing pops out, then repeat on the other side.
3. Push the metal springs off their mountings on the button bar, and ease the bar back through the gap between the two halves.
4. Remove the metal springs from the case by pushing them in the direction they came from — they need a little wobbling to come free.
5. Disconnect the LCD ribbon cable: push both sides of the connector out, then pull the ribbon free.
6. Extract the hinge pins. Make a gap between the pin head and the hinge with a sharp thin blade or a fingernail — take care not to scratch the pin head. Once it has started, grip it with long-nose pliers and pull it out. Put a piece of tape over the plier jaws so they do not mark the pin. On a machine with an already-broken hinge, this stage often just falls apart.
7. The two halves are now separate.

Reassembly

1. Rejoin the halves and push the pins home. If a metal spring needs refitting, make sure it goes into the correct hole behind the bezel.
2. Refit the LCD ribbon: push the sides of the connector out and push the ribbon fully home.
3. Test before you go any further. Connect the mainboard and the keyboard membrane, apply the mains adapter and press Esc. The machine should power up and show the start-up screen. If it does not, the LCD ribbon is almost certainly not seated properly.
4. Feed the button bar back through the gap at the front of the two halves, and locate the small plastic dimples on its sides into the holes beside the battery housing.
5. Refit the springs. The tab of the spring goes into the slot at the rear of the button bar, and at the same time the round part of the spring fits over the round part of the bar. This is the fiddliest step in the job.
6. Reverse the teardown steps.
7. Closing the case is a two-handed job — the bowed button bar catches, so press it flat as you close.

Model differences

Model	What differs
Psion Series 3	Same case and hinges. Different, lower-resolution screen and a different screen ribbon.
Psion Series 3c	Same case and hinges. The SSD door sensing is different — the 3c uses a set of PCB tracks and a small metal connector on the slot door hinge, not microswitches. The 3c also has a rubberised case coating that degrades — handle it before it gets on your tools.
Psion Series 3mx	Same case and hinges, but a pair of angled microswitches sense the SSD doors. Open both SSD doors before lifting the mainboard — prising the board out with the doors closed snaps the plastic tips off those switches, and the machine then refuses to see any SSD.
Psion Siena	A different, smaller case. This procedure does not apply.

Related pages

• Psion Series 3a · Psion Series 3a General Maintenance · Psion Series 3a Troubleshooting Guide
• Psion Series 3 Hinge Repair · Psion Series 3c Hinge Repair · Psion Series 3mx Hinge Repair
• Recommended Tools