I found the (free) precision modelling tutorial to be very good. I am trying to model a hyperbolic roof, and hope to make it by reading through this tutorial.
Thank you.
The precision modeling tutorial is excellent!! Keep up the great work.
Victor
Thanks for the superb 608 bearing tutorial. I am a former engineer and like working to dimensions, so this sort of work is on target for me. Blender is a great program and I look forward to working with it.
Hi Robert, thanks for your Blender tutorials; I have an industrial design background (ie solid modeling), and would love a bit more of a precision modeling approach in Blender, so your tutorials have been helpful. Looking forward to more!
An inspiring e-book.Thank you. 
Thanks for the tutorials. I've never seen so much precision with Blender.
Also I'd like to point out some alternative ways as well. In the very beginning of the bearing tut, the default cube is deleted in order to begin with a new shape. I've seen somewhere else, a different approach: delete all the vertices of the default cube in edit mode and Ctrl + click to start with a new vertices and keep Ctrl +clicking to add vertices to the chain.
(Same thing but a different approach) I've just started watching tutorials. Thanks again.
I have found your Blender tutorials quite useful, and am stunned by the commonality of interests we share: my wife is a potter, I do machining and am interested in foundry work as I'm a live steamer, there's plenty of construction (building shop, and finishing out space over garage). Admire your focus and productivity.
Awesome work on the blender tutorials, Thank you. 
Thank you so much!
Will use my newfound knowledge to create models for my 3D printer, and of course, publish them openly.
If you ever get Flattr to your website and I'll be the first to flatter you 
/Danzig
Thank you so much for sharing your knowledge and experience. As a Blender artist I hugely appreciate input from an engineer. It's exactly what I need more of, particularly when it is so thorough and well presented. Keep up the good work and best wishes.
Script by Dagon Design