segment -PB7/P1
join bot_23lj_b -bot_3lj_b 315 twoarcs
-segment -PC6 120 -PC5
+segment -PC6 120 -PC5 445 -PC4
join bot_3lk -leb_3k 315 arcline
segment -PB6 140 -PB5 200 -PB4
#join -top_45x_br -top_4le0 550 twoarcs
layer 2
+segment -PC4
join -leb_3k top_3lk 389 arcsline
segment -PB4 227 -PB3
join top_45x_tl top_5j3b 1000 twoarcs
layer 0
+
+segment -PC4 100 -PC3
extend top_3lk top_3u1 len 270
+
rel -top_0rm_a top_3u2 35 -111
join top_3u1 top_3u2 800 twoarcs !arcsline
#cross
+segment /
layer 4
extend -rim_3t -rim_3tt len 27.0
layer 2
extend top_3j_b -top_3u3 len 40 -315
+segment -PC3 250 -PC1
join top_3u2 top_3u3 315 arcline
+segment /
layer 6
extend top_3j_a top_5j3c2 len 20 -550