diff --git a/src/papermodels/__init__.py b/src/papermodels/__init__.py
index d160c50..7d57ef4 100644
--- a/src/papermodels/__init__.py
+++ b/src/papermodels/__init__.py
@@ -4,5 +4,10 @@
 
 from . import datatypes
 from . import paper
+from . import scales
+from . import filters
+from . import collectors
+
+from .datatypes.geometry_graph import GeometryGraph
 
 __version__ = "0.18.0"
diff --git a/src/papermodels/collectors.py b/src/papermodels/collectors.py
new file mode 100644
index 0000000..ce2f658
--- /dev/null
+++ b/src/papermodels/collectors.py
@@ -0,0 +1 @@
+from .datatypes.joist_models import JoistArrayModel, CollectorTribModel
diff --git a/src/papermodels/datatypes/element.py b/src/papermodels/datatypes/element.py
index 5d43e85..b7d2041 100644
--- a/src/papermodels/datatypes/element.py
+++ b/src/papermodels/datatypes/element.py
@@ -277,9 +277,14 @@ def get_collector_extents(self, relative: bool = True) -> dict[str, tuple]:
             for idx, poly_support_geom in enumerate(support_geoms):
                 clean_support_geom = support_geoms[idx]
                 cleaned_supports_map.update({clean_support_geom: poly_support_geom})
-                ordered_support_geoms = geom_ops.sort_supports(
-                    self.geometry, support_geoms
-                )
+                try:
+                    ordered_support_geoms = geom_ops.sort_supports(
+                        self.geometry, support_geoms
+                    )
+                except (AssertionError, ValueError):
+                    raise geom_ops.GeometryError(
+                        f"Element {self.tag} appears to have only one support intersection."
+                    )
             try:
                 extents = geom_ops.get_joist_extents(
                     self.geometry,
@@ -287,7 +292,7 @@ def get_collector_extents(self, relative: bool = True) -> dict[str, tuple]:
                     self.trib_area,
                     extent_polygon=self.extent_polygon,
                 )
-            except (AssertionError, ValueError) as e:
+            except (geom_ops.GeometryError, AssertionError, ValueError) as e:
                 raise AssertionError(
                     f"No intersection within joist extents: {self.tag=}"
                 )
@@ -1311,9 +1316,14 @@ def trim_cantilevers(element: Element, abs_tol: Optional[float] = 0.02):
                 [Point(geometry.coords[0]), Point(geometry.coords[-1])]
             )
         )
-        cantilevers = geom_ops.get_cantilever_segments(
-            ordered_geom, support_geoms, abs_tol=abs_tol
-        )
+        try:
+            cantilevers = geom_ops.get_cantilever_segments(
+                ordered_geom, support_geoms, abs_tol=abs_tol
+            )
+        except (AssertionError, NotImplementedError, ValueError):
+            raise geom_ops.GeometryError(
+                f"Received an unexpected geometry for {element.tag} during cantilever trimming."
+            )
         # ordered_geom = LineString(
         #     geom_ops.order_nodes_positive(
         #         [Point(geometry.coords[0]), Point(geometry.coords[-1])]
diff --git a/src/papermodels/datatypes/geometry_graph.py b/src/papermodels/datatypes/geometry_graph.py
index 2979607..71b5b3a 100644
--- a/src/papermodels/datatypes/geometry_graph.py
+++ b/src/papermodels/datatypes/geometry_graph.py
@@ -861,6 +861,7 @@ def from_pdf_file(
         save_tagged_pdf_file: bool = False,
         tag_pdf_file_mode: str = "append",
         show_skipped: bool = False,
+        show_unimplemented: bool = False,
     ):
         """
         Returns a GeometryGraph built from that annotations in the provided PDF file
@@ -893,8 +894,12 @@ def from_pdf_file(
         'process_gravity_frame': Processes the geometry for a gravity frame by fully
             resolving in-plane connectivity
         'show_skipped': Shows the skipped annotations that occured during pdf.load_pdf_annotations
+        'show_unimplemented': Shows the annotations that were read but are not implemented in the
+            parser yet.
         """
-        annotations = pdf.load_pdf_annotations(pdf_filepath, show_skipped)
+        annotations = pdf.load_pdf_annotations(
+            pdf_filepath, show_skipped, show_unimplemented
+        )
         graph = cls.from_annotations(
             annotations,
             legend_identifier,
@@ -1097,6 +1102,7 @@ def plot_elements(
         plot_trib_areas: bool = False,
         plot_extent_polygons: bool = False,
         plot_tags: bool = False,
+        plot_elems_by_tag: Optional[list[str]] = None,
     ):
         """
         Plots all elements in the graph that are on 'page_idx'
@@ -1110,6 +1116,7 @@ def plot_elements(
             plot_trib_areas=plot_trib_areas,
             plot_extent_polygons=plot_extent_polygons,
             plot_tags=plot_tags,
+            plot_elems_by_tag=plot_elems_by_tag,
         )
 
     def create_loaded_elements(self) -> dict[str, LoadedElement]:
diff --git a/src/papermodels/datatypes/joist_models.py b/src/papermodels/datatypes/joist_models.py
index c3708d4..2f7465d 100644
--- a/src/papermodels/datatypes/joist_models.py
+++ b/src/papermodels/datatypes/joist_models.py
@@ -435,9 +435,14 @@ def __init__(
                         break
             self._supports = ordered_supports
         else:
-            self._supports = geom_ops.sort_supports(
-                self.joist_prototype, self.joist_supports.keys()
-            )
+            try:
+                self._supports = geom_ops.sort_supports(
+                    self.joist_prototype, self.joist_supports.keys()
+                )
+            except (AssertionError, ValueError):
+                raise geom_ops.GeometryError(
+                    f"Element {self.element.tag} appears to have only one support intersection:\n{self.element.intersections_below}"
+                )
 
         self.joist_support_tags = [ib.other_tag for ib in element.intersections_below]
         self.id = element.tag
@@ -676,6 +681,18 @@ def generate_joist_geom(self, index: int):
                 end_b, self.vector_parallel, self._cantilever_tolerance / 10
             )
             joist_geom = LineString([end_a, end_b])
+            # TODO:
+            # This will superficially break one of the tests. Do I want to add this in?
+
+            # if not all([joist_geom.intersects(support) for support in self._supports]):
+            #     print(self.element.tag)
+            #     end_a = geom_ops.project_node(
+            #         end_a, -self.vector_parallel, self._cantilever_tolerance / 10
+            #     )
+            #     end_b = geom_ops.project_node(
+            #         end_b, self.vector_parallel, self._cantilever_tolerance / 10
+            #     )
+            #     joist_geom = LineString([end_a, end_b])
         if joist_geom.length <= self._cantilever_tolerance:
             return None
         return joist_geom
@@ -747,7 +764,8 @@ def generate_trib_area(self, index: int) -> Polygon:
             )
         else:
             trib_area_right = Polygon()
-        return trib_area_left | trib_area_right
+        trib_area = trib_area_left | trib_area_right
+        return trib_area
 
     def show_svg(self, use_ipython_display: bool = True):
         """
diff --git a/src/papermodels/filters.py b/src/papermodels/filters.py
new file mode 100644
index 0000000..8ed0191
--- /dev/null
+++ b/src/papermodels/filters.py
@@ -0,0 +1 @@
+from .datatypes.element import create_element_filter
diff --git a/src/papermodels/geometry/geom_ops.py b/src/papermodels/geometry/geom_ops.py
index ed139e3..7c77674 100644
--- a/src/papermodels/geometry/geom_ops.py
+++ b/src/papermodels/geometry/geom_ops.py
@@ -360,8 +360,16 @@ def get_joist_extents(
     right_coords = []
     support_intersection = intersection_all(joist_supports)
     for joist_support in joist_supports:
-        joist_support = joist_support.intersection(box(*supports_bbox), grid_size=1e-3)
-
+        joist_support_trim = joist_support.intersection(
+            box(*supports_bbox), grid_size=1e-3
+        )
+        if not joist_support_trim.geom_type == "LineString":
+            raise GeometryError(
+                f"It seems that a support does not fully intersect with the supports bounding box.\n"
+                "Redraw your supports for this element to ensure they are either properly orthogonal to the element "
+                "or are very clearly at an angle to the element."
+            )
+        joist_support = joist_support_trim
         start_coord, end_coord = joist_support.coords
         start_coord, end_coord = Point(start_coord), Point(end_coord)
 
@@ -750,7 +758,8 @@ def get_system_bounds(
                 if overlap_poly is not None:
                     if extent_polygon is not None:
                         overlap_poly = extent_polygon.intersection(overlap_poly)
-                    overlap_polys.append(overlap_poly)
+                    if overlap_poly.geom_type == "Polygon":
+                        overlap_polys.append(overlap_poly)
         return MultiPolygon(overlap_polys).bounds
 
 
@@ -822,6 +831,8 @@ def sort_supports(
     """
     all_supports = MultiLineString(supports)
     joist_intersections = joist_prototype.intersection(all_supports, grid_size=1e-3)
+    if joist_intersections.geom_type == "Point":
+        joist_intersections = all_supports.intersection(joist_prototype)
     assert joist_intersections.geom_type != "Point"
     assert not joist_intersections.is_empty
     ordered_intersections = order_nodes_positive(joist_intersections.geoms)
diff --git a/src/papermodels/paper/pdf.py b/src/papermodels/paper/pdf.py
index 57f6ca0..8f90225 100644
--- a/src/papermodels/paper/pdf.py
+++ b/src/papermodels/paper/pdf.py
@@ -13,7 +13,9 @@
 
 
 def load_pdf_annotations(
-    pdf_path: pathlib.Path | str, show_skipped: bool = False
+    pdf_path: pathlib.Path | str,
+    show_skipped: bool = False,
+    show_unimplemented: bool = False,
 ) -> list[Annotation]:
     """
     Returns a lists of pdf annotations keyed by page index.
@@ -30,7 +32,11 @@ def load_pdf_annotations(
                 continue
             for annot_idx, annot in enumerate(page_data.obj.Annots):
                 pm_annot = pike_annotation_to_pm_annotation(
-                    annot, annot_idx, page_num, rotate
+                    annot,
+                    annot_idx,
+                    page_num,
+                    rotate,
+                    display_unimplemented_annots=show_unimplemented,
                 )
                 if pm_annot is not None:
                     annots_in_pdf.append(pm_annot)
@@ -109,7 +115,11 @@ def compare_annotations(
 
 
 def pike_annotation_to_pm_annotation(
-    annot, annot_idx: int, page_idx: int, rotate: Optional[int] = None
+    annot,
+    annot_idx: int,
+    page_idx: int,
+    rotate: Optional[int] = None,
+    display_unimplemented_annots: bool = False,
 ) -> Optional[Annotation]:
     """
     Returns either an Annotation object or None. None is returned if:
@@ -159,7 +169,8 @@ def pike_annotation_to_pm_annotation(
         vertices = tuple(annot.get("/L", tuple()))
         annot_type = "Line"
     else:
-        print(f"Cannot read (yet): {annot_type}")
+        if display_unimplemented_annots:
+            print(f"Cannot read (yet): {annot_type}")
         return None
     if rotate == 90:
         vertex_array = geom_ops.vertices_to_array(vertices)
diff --git a/src/papermodels/paper/plot.py b/src/papermodels/paper/plot.py
index b143191..4e6006f 100644
--- a/src/papermodels/paper/plot.py
+++ b/src/papermodels/paper/plot.py
@@ -20,6 +20,7 @@ def plot_elements(
     plot_trib_areas: bool = False,
     plot_extent_polygons: bool = False,
     plot_tags: bool = False,
+    plot_elems_by_tag: Optional[list[str]] = None,
 ) -> Figure:
     """
     Plots the elements in matplotlib. Size and dpi can be adjusted
@@ -61,6 +62,7 @@ def plot_elements(
         "extent_face": (0.8, 0.7, 0.0),
         "prototype_line": "yellow",
     }
+    highlight_tags = False
     plot_objs = []
     for element in elements:
         plot_attrs = get_element_plotting_attributes(element, is_subelement=True)
@@ -82,9 +84,17 @@ def plot_elements(
             max_extent = np.maximum(max_extent, np.max(xy, axis=1))
 
         # For tagging
-        initial_positions_x.append(po["anchor_point"][0])
-        initial_positions_y.append(po["anchor_point"][1])
-        tags.append(po["tag"])
+
+        if plot_elems_by_tag is None:
+            tags.append(po["tag"])
+            initial_positions_x.append(po["anchor_point"][0])
+            initial_positions_y.append(po["anchor_point"][1])
+        else:
+            if po["tag"] in plot_elems_by_tag:
+                highlight_tags = True
+                tags.append(po["tag"])
+                initial_positions_x.append(po["anchor_point"][0])
+                initial_positions_y.append(po["anchor_point"][1])
 
         if po["is_poly"]:
             ax.add_patch(
@@ -161,6 +171,9 @@ def plot_elements(
         min_extent[1] - plot_margin_metric * 0.05,
         max_extent[1] + plot_margin_metric * 0.05,
     )
+    text_color = "k"
+    if highlight_tags:
+        text_color = "r"
     ta.allocate(
         ax=ax,
         x=initial_positions_x,
@@ -169,7 +182,7 @@ def plot_elements(
         # x_lines=lines_x,
         # y_lines=lines_y,
         textsize=8,
-        textcolor="k",
+        textcolor=text_color,
         linecolor="k",
         avoid_label_lines_overlap=True,
         avoid_crossing_label_lines=True,
@@ -246,12 +259,15 @@ def plot_annotations(
     figsize: int | float | tuple[int | float, int | float] = (17, 11),
     dpi: float = 100,
     plot_tags: bool = False,
+    plot_annots_by_tag: Optional[list[str]] = None,
 ) -> Figure:
     """
     Plots that annotations, 'annots' in matplotlib. Size and dpi can be adjusted
     to make the plot bigger/smaller. Size is in inches and dpi stands for
     "dots per inch". For a biggish plot, values of size=12, dpi=200 gives
     good results.
+
+
     """
     if isinstance(figsize, (int, float)):
         figsize = (figsize, figsize)
diff --git a/src/papermodels/scales.py b/src/papermodels/scales.py
new file mode 100644
index 0000000..9d7a176
--- /dev/null
+++ b/src/papermodels/scales.py
@@ -0,0 +1,89 @@
+from decimal import Decimal
+
+Decimal()
+
+
+class Scale(Decimal):
+
+    def __new__(cls, factor, name):
+        instance = super().__new__(cls, factor)
+        instance.name = name
+        return instance
+
+    def __repr__(self):
+        return f"Scale: {self.name} | factor: {self}"
+
+
+SCALE_1_TO_1000 = Scale(
+    Decimal("1") / Decimal("72") * Decimal("25.4") * Decimal("1000"), "1:1000 Scale"
+)
+SCALE_1_TO_500 = Scale(
+    Decimal("1") / Decimal("72") * Decimal("25.4") * Decimal("500"), "1:500 Scale"
+)
+SCALE_1_TO_200 = Scale(
+    Decimal("1") / Decimal("72") * Decimal("25.4") * Decimal("200"), "1:200 Scale"
+)
+SCALE_1_TO_100 = Scale(
+    Decimal("1") / Decimal("72") * Decimal("25.4") * Decimal("100"), "1:100 Scale"
+)
+SCALE_1_TO_50 = Scale(
+    Decimal("1") / Decimal("72") * Decimal("25.4") * Decimal("50"), "1:50 Scale"
+)
+SCALE_1_TO_20 = Scale(
+    Decimal("1") / Decimal("72") * Decimal("25.4") * Decimal("20"), "1:20 Scale"
+)
+SCALE_1_TO_10 = Scale(
+    Decimal("1") / Decimal("72") * Decimal("25.4") * Decimal("10"), "1:10 Scale"
+)
+
+SCALE_1_TO_1000_M = Scale(
+    Decimal("1") / Decimal("72") * Decimal("25.4") * Decimal("1000") / Decimal("1000"),
+    "1:1000 Scale, in meters",
+)
+SCALE_1_TO_500_M = Scale(
+    Decimal("1") / Decimal("72") * Decimal("25.4") * Decimal("500") / Decimal("1000"),
+    "1:500 Scale, in meters",
+)
+SCALE_1_TO_200_M = Scale(
+    Decimal("1") / Decimal("72") * Decimal("25.4") * Decimal("200") / Decimal("1000"),
+    "1:200 Scale, in meters",
+)
+SCALE_1_TO_100_M = Scale(
+    Decimal("1") / Decimal("72") * Decimal("25.4") * Decimal("100") / Decimal("1000"),
+    "1:100 Scale, in meters",
+)
+SCALE_1_TO_50_M = Scale(
+    Decimal("1") / Decimal("72") * Decimal("25.4") * Decimal("50") / Decimal("1000"),
+    "1:50 Scale, in meters",
+)
+SCALE_1_TO_20_M = Scale(
+    Decimal("1") / Decimal("72") * Decimal("25.4") * Decimal("20") / Decimal("1000"),
+    "1:20 Scale, in meters",
+)
+SCALE_1_TO_10_M = Scale(
+    Decimal("1") / Decimal("72") * Decimal("25.4") * Decimal("10") / Decimal("1000"),
+    "1:10 Scale, in meters",
+)
+
+SCALE_32ND_INCH = Scale(Decimal("1") / Decimal("72") * Decimal("32"), '1/32" = 1\'-0"')
+SCALE_16TH_INCH = Scale(Decimal("1") / Decimal("72") * Decimal("16"), '1/16" = 1\'-0"')
+SCALE_EIGHTH_INCH = Scale(Decimal("1") / Decimal("72") * Decimal("8"), '1/8" = 1\'-0"')
+SCALE_QUARTER_INCH = Scale(Decimal("1") / Decimal("72") * Decimal("4"), '1/4" = 1\'-0"')
+SCALE_HALF_INCH = Scale(Decimal("1") / Decimal("72") * Decimal("2"), '1/2" = 1\'-0"')
+SCALE_ONE_INCH = Scale(Decimal("1") / Decimal("72"), '1" = 1\'-0"')
+
+SCALE_3_32ND_INCH = Scale(
+    Decimal("1") / Decimal("72") * Decimal("32") / Decimal("3"), '3/32" = 1\'-0"'
+)
+SCALE_3_16TH_INCH = Scale(
+    Decimal("1") / Decimal("72") * Decimal("16") / Decimal("3"), '3/16" = 1\'-0"'
+)
+SCALE_3_EIGHTH_INCH = Scale(
+    Decimal("1") / Decimal("72") * Decimal("8") / Decimal("3"), '3/8" = 1\'-0"'
+)
+SCALE_3_QUARTER_INCH = Scale(
+    Decimal("1") / Decimal("72") * Decimal("4") / Decimal("3"), '3/4" = 1\'-0"'
+)
+SCALE_3_HALF_INCH = Scale(
+    Decimal("1") / Decimal("72") * Decimal("2") / Decimal("3"), '3/2" = 1\'-0"'
+)