---
jupyter:
  description: 'Production drawings of a flange series with planex2d: one constraint sketch with named dimensions and a
    rule for its bolt circle, updated to every size of its design table, and a dimensioned drawing with a DIN title
    block for each size, written as PDF.'
---

# Flange drawings from a design table

A part made in several sizes can be documented on one tabulated drawing, with its dimensions as letters and a table of
their values, as in the exercise [Flange series](../exercises/flange-series.md). A drawing per size is the other way.
Each size gets its own sheet and drawing number, with the values written out, so that the workshop reads them off
without a table. When the sizes come from one parametric model, these drawings are not drawn one by one. Each one is
the model, updated to a row of its design table, drawn again.

The example is the flange of that exercise in its three sizes, a disc with a bore and holes on a bolt circle midway
between the bore and the outside. Lengths are in mm.

This page is part of a collection of [manufacturing examples](manufacturing.md) using planex2d.

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.. rst-class:: px-example-links

`Open this example in the playground <https://planex2d.org/playground/>`__, the interactive code editor in the browser, to change the code and run it.
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![The drawing of a flange of size C, a disc with a bore and eight holes on a bolt circle, every dimension written out](../_static/gallery/flange-drawings.png){.result}

```python
import planex as px
```

```python nbsphinx="hidden"
from docs_figures import Row
```

## The model

The sketch is the exercise's, with one change for the drawings. The bolt circle is a construction circle through the
first hole's center, and its diameter `k` is a dimension, which a drawing shows like any other. An expression ties it
to the rule $k = (D + d)/2$, so that it follows the outside and the bore in every size. `CircularPattern` repeats the
hole, with the number of holes as the dimension `holes.count`. The dimensions have the letters of the design table as
their ids (Figure 1):

```python
flange = px.Sketch(auto_constraint=True)
flange.Circle(50, id="outside")
flange.Circle(15, id="bore")
flange.Circle(32.5, construction=True, id="pitch")
flange.Circle(5.5, center=(32.5, 1), id="hole")
flange.Constrain("outside.center", "origin", px.Coincident)
flange.Constrain("hole.center", "pitch", px.Coincident)
flange.Constrain("hole.center", "H", px.Coincident)
flange.Constrain("outside", px.Diameter, 100, id="D")
flange.Constrain("bore", px.Diameter, 30, id="d")
flange.Constrain("pitch", px.Diameter, 65, id="k")
flange.Constrain("hole", px.Diameter, 11, id="l")
flange.Expression("k = (D + d) / 2", id="bolt_circle")
flange.CircularPattern(["hole"], "origin", 4, id="holes")
print("status", flange.status, "| degrees of freedom", flange.dof)
# flange.Plot(show_constraints=True)
```

```python nbsphinx="hide-input"
Row((flange, "Every dimension and tie of the sketch, at size A", {"constraints": True}), caption="The flange's sketch")
```

## A drawing per size

The design table has a row of dimensions for each size, in the form that `sk.ReadSpreadsheet` returns from a
spreadsheet. `px.Drawing` keeps the sketch by reference, so one drawing serves all sizes. For each row, `Update` solves
the sketch, the drawing's own `Update` draws it again, and `px.Sheet` puts it on an A4 sheet with a frame and planex2d's
default title block. The block fills in the scale, the paper size, the date and the sheet number itself, and the drawing
number names the size. The bolt circle's diameter stands on a leader at 67.5°, which runs between the holes in every
size. Each sheet is written as a PDF:

```python
sizes = {"A": {"D": 100, "d": 30, "l": 11, "holes.count": 4},
         "B": {"D": 125, "d": 45, "l": 13.5, "holes.count": 4},
         "C": {"D": 160, "d": 60, "l": 13.5, "holes.count": 8}}
drawing = px.Drawing(flange, unit=px.mm).Place("k", 67.5, leader=True)
for name, size in sizes.items():
    flange.Update(size)
    drawing.Update()
    sheet = px.Sheet(drawing, frame=True)
    sheet.Title(title="Flange", subtitle=f"Size {name}", number=f"FL-{size['D']}")
    sheet.WritePDF(f"flange_{name}.pdf")
    print(name, "k", flange["k"], "| (D + d) / 2", (size["D"] + size["d"]) / 2, "| holes", flange["holes.count"])
```

The sheet of the last size, C, as it is written to its PDF:

```python
sheet
```

The drawings as PDF: [flange_A.pdf](flange_A.pdf), [flange_B.pdf](flange_B.pdf), [flange_C.pdf](flange_C.pdf)

See [Views and sheets](../core/drawings/sheets.md) and [Title blocks and files](../core/drawings/title-blocks.md) for
sheets and title blocks, and [Design tables in a spreadsheet](../core/constraints/spreadsheets.md) for rows read from a
file.

```python nbsphinx="hidden"
import sys
sys.path.insert(0, "..")
from gallery import save_sheet
save_sheet(sheet, "flange-drawings")
```