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Sjouke Burry[_2_] Sjouke Burry[_2_] is offline
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Default A specific PCB bad practise, term for it ?

who where wrote:
On Sat, 23 Apr 2011 16:24:17 +0100, "N_Cook"
wrote:

Where holes are drilled for thru-board components but of diameter far too
big , thru-hole plated , but no eyelet/inserts used to fill the gap. So
1N4001 size leads in holes twice their diameter and 1N4148 in holes twice
their diameter. So not a case of only one drill size for all. So in area
terms about 1 to 4 ratio of lead to solder. Bad enough practise with proper
solder but with PbF, ring cracks starting all over.
Is it to avoid mutiny by the by-hand board populators ?


It was always my understanding that the "oversized" PTH was a
deliberate choice. If significant current needs to pass to both
planes, a (proper, of course, not RoHS) solder plug enhances the
through-plating's capability.


The blob of solder has much less resistance than the
very thin copper surrounding the hole.
Mass counts here, and the copper is at a big disadvantage there.