I went to my tried and tested method of using distilled vinegar in the end, which I know works a treat and did so again. Plus I already had some and didn't have to go shopping.
I used on of those infuser gadgets that you put loose tea in or herbs or spices in a mulled wine. This again worked a treat and in a couple hours of occasional stirring the brass was as shiny as was when it was etched. The problem occurred when I rinsed the parts under a tap in the sink. The water came out much quicker than I expected and washed a few parts out of the infuser and down the drain. Oh dear, or words to that effect.
I took the U-bend off and searched for the parts in the sludge in the tube. Happy that I had found them all I dried them by a window and set off to the club for a soldering extravaganza. Half a days worth of cussing and singeing produced the results below. Please excuse my lack of cleaning up at this stage.
The keen-eyed of you will notice that I didn't, in fact, find all the parts that were washed away down the plug hole. The bottom right door has a missing door roller - a deceased casualty of the war between gravity and stupidity. I didn't bring a broach with me so I couldn't size up the holes for the door handles but I'll prep these for another battle next month.
