First post, by SSTV2
- Rank
- Oldbie
Foreword - this is the first time I've ever had to repair a CPU socket, but I've used method shown here in the past to repair broken plastic parts, that were meant to flex or take a load, with good results, thus I'm confident in its effectiveness.
Motherboard of interest here is an Acorp 6LX87, an AT form factor s370 board based on the intel 440LX chipset and is designed to be used with Mendocino Celerons only. I've been considering for some time to restore this motherboard and swap it with another AT board based on the VIA Apollo Pro chipset, which, to put it mildly, just wastes space in an AT case with its poor performance.
I'll explain all the key steps it took me to recreate a tab that was broken off and lost, if you still have the original tab piece laying around, it will take far less steps to repair it and the end result will be even better.
If you are left with nothing...
- Step 1 - preparing what is left of the broken tab for drilling holes:
Metal rods - the basis of a proper tab repair, these rods will bear most of the load from the heatsink spring clip and in order to drill properly aligned holes for them, it is important to mark the drilling locations with small pits fist. Aim to leave the marks on the lowest possible point. The break was not flush in my case and it was difficult to leave marks on an unevenly angled plastic, thus it was necessary to file off some of it first to make surface flat enough. A sharpened wood screw was used as a marker.
- Step 2 - drilling holes:
For that I used a 0.7 mm drill bit, drilled all the way until the drill bit protruded on the other side of the socket's pin holes. If the broken tab is in a hard to reach place, you will have to purchase or make an adapter for the drillbit (cable based).
- Step 3 - making metal rods:
Metal rods were formed from a solid 1 mm MIG welding wire (hard but not brittle), wire diameter was reduced down to ~0.75 mm, a drill and a sanding belt were used to achieve this. Wire was left just a tad bit wider than the drill bit so that it would hold in the holes without the need of glue. Next, cut up a newly formed wire into the required length rods, measure the depth, that they will have to go in, mark this depth with a marker pen and hammer them in carefully.
- Step 4 - mold:
The mold was made of plasticine, a square shape of the required width was formed with the help of a accordingly cut up vine bottle cork.
- Step 5 - resin preparation:
I used a two-part epoxy resin, that was mixed with white plastic powder (to better match the color/texture). I originally planned to mix this powder with cyanoacrylate glue, but decided to abandon this idea for fear of ruining the tab if something would go wrong.
- Step 6 - shaping:
After about 15 hours of curing, the resin was hard enough to retain its shape but also soft enough to be trimmed with an exacto knife. The excess resin was cut off where needed and a file was used to make final adjustments to the newly formed tab shape. It takes approx. from 3 days to a week for the epoxy to fully cure.
End result:
If the tab is not lost yet...
- Step 1 - mark the front of the tab and drill two holes in it, but not all the way through (a 0.5 mm drill bit might be required).
- Step 2 - glue the tab to the socket with cyanoacrylate glue, ensure minimal gaps between them.
- Step 3 - now drill through the tab all the way into the socket as far as plastic allows it, insert the metal rods into the newly made holes and if the rods move freely, apply some glue to them.
Note that the spring tension of the heatsink clip should be lowered in any case, if a repaired tab breaks again, then the entire socket may have to be replaced. If you have previously repaired or intend to repair similar CPU sockets, don't forget to share your experience 😉
