<soapbox>
A jury-rig is the rig you put together out of whatever is available after
the vessel is dismasted.  Jury-rigging is a high form of seamanship and the
term "jury-rigged" or "a jury-rig" is simply descriptive.

Jerrybuilt is built sloppily and carelessly, from dialectal jerry, possibly
from a name (paraphrased from AHD3).  It is a term of denigration.

Jerry-rigged is simply a mistake; there is no such word.  Typically used to
mean jerrybuilt.

While I'm up here, there is no such thing as a "nor'easter" -- this is an
invention by (I presume) weather people trying to sound smart and
failing.  In nautical usage, directions containing "west" have the initial
North or South ellided to Nor' or Sou' -- while directions containing
"east" have the "th" in North and South emphasized.  This is to prevent
confusion between east and west, which have similar sounds.  So, a
nor'wester, but a noTHeaster...

</soapbox>

david

David Beierl - Providence, RI
  http://pws.prserv.net/synergy/Vanagon/
'84 Westy "Dutiful Passage"
'85 GL "Poor Relation"