Cheers chaps.
Yes, I suspect this would be a non-issue if I'd only done new chains; while the old ones were cleaned as thoroughly as possible by going through numerous jars of paraffin and being scrubbed with a toothbrush to remove external contamination. Evidently this wasn't sufficient. Besides, given that the contam is all bits of metal, I suspect that most of it has been washed out from between the links of the chains.
Thanks for the thought about the wire platform @Sea of vapours - unfortunately I don't have anything that fancy!
Yes, I suspect this would be a non-issue if I'd only done new chains; while the old ones were cleaned as thoroughly as possible by going through numerous jars of paraffin and being scrubbed with a toothbrush to remove external contamination. Evidently this wasn't sufficient. Besides, given that the contam is all bits of metal, I suspect that most of it has been washed out from between the links of the chains.
Thanks for the thought about the wire platform @Sea of vapours - unfortunately I don't have anything that fancy!