All the etches are back from PPD, who as usual have done a good job. They are very shiney. Fingers crossed that it all fits, and I've not omitted anything important to the design.
In a shocking turn of events, I am investigating the use of 3D printed patterns. I have taken some convincing that the quality of this process can match that of handmade patterns, but I believe the process might now be satisfactory for certain types of part which are either cast on the prototype and/or do not rely on a very smooth overall surface finish.
I've posted a couple of my digital patterns to make a comparison with the patterns I make manually or by analogue processes. I quite enjoy modelling parts in CAD, and compared with the 2D AutoCAD parts, these are nicer to work on as they don't rely on on fitting their neighbouring parts in quite the same way. Just as with hand made patterns, I can only expect them to be as good as the information and effort put into them before they are cast. The wheel pattern will be adapted so that it can be machined to fit a tyre - I don't intend to cast the tyre.
There are a number of pitfalls I can see with digital patterns, based mainly on my nature. Literally all detail can be included whether practical or sensible or neither. The smallest thing can be modelled with ease without regard to how well it will reproduce. It's very easy to loose sight of a detail that adds time to making the model but nothing at all to the finished model.
For my digital pattern making I grasped the function of Fusion360 and find it's quite impressive for a package that can be so easily downloaded. I wouldn't say it's anything like as robust as SolidWorks, or as powerful, but that is definitely not what it is aimed at.
Once I am satisfied with the CAD models I intend to have them printed in a castable wax, omitting the mouldmaking part usually associated with the lost wax process. The aim is to reduce loss of resolution by using one fewer process, and to maintain dimensional stability. However, my caster pointed out that castings of the wax masters, if given the right shrinkage allowance can also be used as patterns once cleaned and polished if I am in particular need of a very good surface finish. We will see.
If some of these don't work out I can still use each 3D model to generate a dimensioned drawing and do it all by hand...
So, I'm jumping in with both feet and hoping for the best!
Best regards
Tom