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</o:shapelayout></xml><![endif]--></head><body lang=EN-NZ link="#0563C1" vlink="#954F72" style='word-wrap:break-word'><div class=WordSection1><p class=MsoPlainText>> using a border line instead of an invisible wall for scrap borders in centre of a passage / open space<o:p></o:p></p><p class=MsoPlainText><span style='color:black'><o:p> </o:p></span></p><p class=MsoPlainText><span style='color:black'>There are a number of considerations here. This wiki post describes them <a href="https://therion.speleo.sk/wiki/drawingchecklist#wall">https://therion.speleo.sk/wiki/drawingchecklist#wall</a> <o:p></o:p></span></p><p class=MsoPlainText>It may be that using <span style='font-family:"Abadi Extra Light",sans-serif'>line wall -visibility off</span> is a better solution than either <span style='font-family:"Abadi Extra Light",sans-serif'>line wall -subtype invisible</span> or <span style='font-family:"Abadi Extra Light",sans-serif'>line border -outline out -visibility off<o:p></o:p></span></p><p class=MsoPlainText><span style='color:black'><o:p> </o:p></span></p><p class=MsoPlainText><span style='color:black'>Tarquin’s overall approach is how I would do it. Always end/start surveys between pillars, and each open end of a scrap only joins with one other scrap, to avoid the open triangle in the apparent interior of the cave. Even if you make a mistake in the field and end a survey in the middle of a void far from the pillars, strategic drawing of the scrap walls can mitigate the problem. Imagine Tarquin’s sketch attachment with say the left-hand survey station missing, so the station joining with another survey to the left is in the centre of the void. So you draw the sketch exactly as Tarquin has (with walls defining the pillars at distant-left, just there is no station between them) and it will work.<o:p></o:p></span></p><p class=MsoPlainText><span style='color:black'><o:p> </o:p></span></p><p class=MsoPlainText><span style='color:black'>See also <a href="https://therion.speleo.sk/wiki/faq#how_do_i_join_three_scraps_in_a_y-shape">https://therion.speleo.sk/wiki/faq#how_do_i_join_three_scraps_in_a_y-shape</a>. The XTherion ‘tricky’ image demonstrates a simple case. What is really happening is that a three-scrap join is turned into a series of two-scrap joins. These can then be joined semi-automatically as described in <a href="https://therion.speleo.sk/wiki/tips#joining_scraps_together">https://therion.speleo.sk/wiki/tips#joining_scraps_together</a> <o:p></o:p></span></p><p class=MsoPlainText><span style='color:black'><o:p> </o:p></span></p><p class=MsoPlainText><span style='color:black'>Bruce<o:p></o:p></span></p><p class=MsoPlainText><span style='color:black'><o:p> </o:p></span></p></div></body></html>