Yes, its true there is a strong and weak 4k block(s).
Not sure how many weak ones there were, but apparently there was not many made at all.
Tell them apart by looking at any old 4k block. Look at the welsh plugs - if there is ribbing going between each of the 4 welch plugs, its a standard "stong" 4k. If it doesnt have the ribbing between the welsch plugs, its a rare week block, and boring them out = dumb... wont be long before the block cracks.
Sat, 13 August 2005 23:03
