Precision Drawing Tools

This is now the Official Page for my Precision Drawing Tools Add-on.

This is the version with the UI (N Panel) Interface, for Blender 2.8 Only.


PDT now ships with Blender Official Releases, you can also download latest release as shown below.

Download PDT for Blender 2.8 Only from the Download Page.


Same as any Blender Add-on, from Preferences=>Addons, Install, select zip file and enable.

N-panel Version: Animation Nodes is not required; Enable Prefs->addons->3d View:Precision Drawing Tools.


This Add-on now has a Wiki stored on the PDT Repository.

I have started to write some Help Pages, see right side menu.

A “Getting to Know PDT” video has been made, no commentary since I sound like a muppet when doing these, but there are lots of comments to help and screencast keys to show which buttons, mouse bits, etc. I was playing with.

I may do more of these, if someone wants to add the voice, just contact me.


12/02/2019 – Latest version; 1.2.0 is to ship with official Blender 2.82. Next development – the ability to draw tangents to arcs/circles is under way.

9/12/2019 – Following review by Blender Foundation, PDT is now approved for shipping with Blender and will be in builds of 2.8 from now I believe. A big thank you to the Blender Devs and to Ermo for all his work in getting the code up to standard, including format and Docstrings. There is still work to do on the Wiki, which needs more explanation of workflow and CAD design principles. These are underway with the building of this model:

A new page will detail the building process using PDT, the workflow and principles involved. the model is a book scanner using two compact cameras, is made from mainly birch ply and I will be producing technical drawings of all the parts so they can be laser cut and the real thing built – at some point in the future.

9/10/2019 – Following a discussion with the author of the TinyCAD Add-on, we (Ermo, is now helping with this project) have been given permission to build some of the TinyCAD processes into PDT, namely Extrude Edge to Face, Bisect Edges and Intersect All We have also added a Fillet Tool, that works on edge loops. We have also added a scale feature that works on two dimensions (Before and After) rather than users having to do the maths, more once the next release is available.

Some examples:

These features will be available in release 1.1.5, we hope to have a Release Candidate available for testing before end October 2019, after a very large amount of “janitorial” work has been completed, including “Black” code formatting, Messages file to facility multi-language versions and code optimising and cleaning. The next stage will be to look at integrating other Draughting Functions and introducing Gizmos to further enhance the User eXperience.

Interface Version 1.1:


You can follow developments on this Blender DevTalk Thread.

An Example of PDT Preferred Topology, designed for Precision Work, not Aliens!

New Features have been added as of 15/09/2019, see the Download Page for details.

Version 1.1 of 10/09/2019 now has a Pivot Point, which can be used to rotate, or scale geometry independent of the 3D Cursor, it does not move geometry, there are already so many ways to do this. There is a Show button to show the Pivot Point, this button then changes to Hide to hide it.

It also has a Command Input, which activates when you press Return. this takes two letters, followed by numbers separated by commas “,”. Valid Primary letters are, can be capitals, or lower case:

  • C = Cursor commands.
  • P = Pivot commands.
  • E = Extrude Geometry commands
  • G = Grab, or move commands.
  • N = New Vertex commands.
  • D = Duplicate commands
  • V = Extrude vertices only, not their edges, or faces.
  • S = Split Edges.

Valid Secondary letters are, can be capitals, or lower case:

  • A = Absolute, or World coordinates and requires 3 numbers separated by 2 commas, zeros may be omitted, so cd2,,1 is valid.
  • D = Delta, or incremental coordinates and has the same requirements as A.
  • I = Direction and requires a distance and an angle, separated by a comma, from View Horizontal, so ei2,135.6 means extrude geometry 2 units at 135.6 degrees from positive view X axis. Valid Angle range is +-180.
  • P = Use a percentage value to, for example, split an edge, so sp30 means split edge at 30% of the way along it.

I will make a new Help page for this release, but it will take some time as I am very busy! Contact me via the contact page, if you have any questions, or spot any little bugs. 🙂 Meanwhile most of what is below will help and I have added Tool-Tips and Error Messages to assist. THIS IS STILL BETA grade software and only 5 weeks (as of 10/09/2019) into development from me not knowing how to even start making an Add-on…

Bear in mind that if you are in View Plane – all operations are carried out in the View’s own Local Axes, not global axes, as is the case for the other view options.

PDT Is not meant as a replacement for Blender Modelling Functions, merely to augment them. if you would normally extrude along the X Axis by typing EX1.5 for example, keep doing that, it is still valid!

Examples of where this is going; to produce Technical Drawings from accurate models in Blender:

These were produced with PDT, MeasureIt and Offset-Edges Add-ons in Blender 2.80.


This is a depository for common used parts as objects in a library blend file located with the Add-on. Routines in PDT will enable the user to retrieve parts and to place them automatically at the cursor location. Materials and Collections are also handled by this function suite:

The Add-on ships with a very simple library that you can edit in the normal Blender way. in time, I hope to be able to post objects from your current open blend file into the library.

I am currently working on this website, please excuse any little upsets!