After carefully paring off the moulded-on security icon with a sharp chisel, I carved a vertical rectangular hole in the case of my 512Ke, thereby obliterating the 'security lug' hole and as few signatures inside the bucket as possible. Into the hole I put the centre portion of the alternative battery cover, provided by Dove with the upgrade, and having ready-made provision to mount the SCSI DB-25F port. It was a force-fit, prevented from going right through the case by my also having left a rectangular flange of plastic around the shaped opening for the female DB-25 and locking pillars. The end result is a recessed well in which the female connector and pillars are flush with the outer case surface.
Then hied I me to Bunnings (a hardware supermarket chain) for some pure MEK, which is freely available in Australia as a PVC-U pipe cement primer for both electrical and plumbing use. It is used to clean/wet the ends of pipes before the more viscous cement is brushed on and the pipes are force-fitted into their unions. Into about 50mL of MEK in a glass jar with a screwcap and gasket I put the surviving fragments of the Dove battery door, and left the lot overnight. The solution was still quite freely-flowing, but completely opaque from the dissolved ABS. With a piece of 2-mm brass tube, crimped almost shut at one end to make a 'pipette', I ran ABS solution into the inside and through-case joints. Worked a treat. After four applications at intervals to allow the free MEK to evaporate, I could no longer see the joints. I'll give it a week to let the MEK dry thoroughly, and then see how the joint survives the insertion force of attaching a SCSI cable to the female SCSI port mounted on my improvised recess.
So, MEK is a good solvent for ABS plastic.
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