Sonoma Pilot Master Project

[W.P. Rayner]

Spent the past two weeks preparing drawings and renderings of the pilot for the Sonoma loco as on display in the California State Railroad Museum. Ultimate purpose is to prototype the pilot for casting in brass in 1:48 for a limited production run of the Baldwin 4-4-0s. Drawings will be presented by the client at the O Scale West convention later this week.

First photo is of the NPC #9 showing original pilot, a little worse for wear. Second photo is the pilot as reconstructed and on display at the California State Railroad Museum. Third is my rendering of the pilot from my drawings which will be used to prototype the master. One change made: the original pilot was riveted together, hence the rivets in my drawing. The reconstruction was bolted together for ease and cost-effectiveness, as were repairs done to the original pilots once in service. Larger versions of these photos can be seen in the Portfolio section on my web site.







Paul

[Ray Dunakin]

Really fine CAD work! It looks better than the real thing.

[finescalerr]

Looks great ... but the real one is more shiny. Wax the rendering! -- ssuR

[Chuck Doan]

Really nice Paul. Did someone provide the dimensions?

[EZnKY]

Wow!
Very impressive modeling , especially given the complex forms and curves!

[W.P. Rayner]

Thanks guys (wax comment notwithstanding...  ). This was definitely a geometrically challenging project.

Here's another rendering, ground-level side view, which is being added to the presentation at O Scale West on Thursday.



Chuck: I was fortunate to be provided with the Museum's construction drawing for their reconstruction of the pilot which served as a good starting point. However, while the overall width and length of the pilot remains the same as the prototype, the model version is two scale inches taller overall in order to fit properly on the model locomotive. This dimensional change meant all the cord lengths and bend angles on the curved angle iron pieces had to be changed in order to fit properly. We suspect that the dimensions notated on the Museum's drawing were actually added after the pilot was built as they were all slightly inaccurate and mathematically inconsistent, however they did serve as a good starting reference.

Paul

[Wesleybeks]

Stunning work Paul. What programme do you draw in?

[W.P. Rayner]

Thanks Wesley. I draw in Autodesk Inventor Pro 2012. Up until today I rendered with Keyshot 2, but today I upgraded to Keyshot 3 Pro. Rendering below is the first from the new app. Had to make a few minor changes in the pilot, mostly to ease the mounting of the finished brass pilot. As before there is a larger version of this image on view on my web site.

And yes Russ, I waxed it this time...  



Paul

[finescalerr]

Okay, fine, you waxed it. But did you clean the dry wax from the joints and around the rivets? -- ssuR

[Hauk]

We could of course have a long meta-discussion regarding if this is real modelling
But I think I will restrain myself to the triple-I:

Interesting, Impressive and Inspiring!

But how do you plan to transform this beauty into reality? If this was my project  I think I would have used a service provider than can provide metal masters (silver or brass) based on a wax print from a solidscape printer.

Regards,
Hauk

[W.P. Rayner]

Russ: No I didn't, I have a thong-clad cutie who rubs away the wax for me....

Hauk: Thanks for the compliment. As far as the prototyping material, we are considering several options, one of which is a metal material. Unfortunately the resolution I've seen on the metal processes to date has been universally too coarse, at least for a part of this diminutive size and delicacy. It would be fine if this were being produced in a 1:24 or larger scale. The client is a machinist and partnered with a long-established casting business and is leaning towards having the part prototyped in a micro-fine resin. It will then be molded and a bronze part cast from the mold. The bronze will become the actual master part from which the production pieces will be cast.

Thank you also for restraining. As far as the discussion of whether this is modelling or not, I consider that to be a irrelevant issue much like the age-old discussion of whether photography is an art form. As a life-long model-maker, designer and photographer, I've found it to be a much better and more gratifying use of time and energy to be actually doing the work than climbing a soap box to talk about it. Many years ago I met with the British photographer Bill Brandt trying to convince him to take part in a symposium at a museum where I worked. He refused, as he always did, saying that he would much rather take photographs than talk about taking photographs, a philosophy that has stuck with me every since.

Paul

[finescalerr]

The finished piece should be gorgeous and the method you are planning seems a good one. Please photograph the thong clad cutie holding the pilot when it is complete. -- Russ

[W.P. Rayner]

Latest update...

Rendering below is latest image of the pilot after making some subtle design changes. Rendering completed in Keyshot 3 Pro, for those who keep track of that sort of thing.



Now we are in the prototyping phase of this project. The image below shows the first wax tests in 1:48. Note: the drawbar is being printed as a separate assembly. These were printed on a 3D Systems CPX 3000Plus machine with 16 micron (or .0006") layer thickness. Pilots are approximately .625" H. x 1.375" W. x 1.375" L., pretty tiny. The web thickness on the angle irons is to scale at .0075" T. They turned out beautifully (Apologize for less than ideal photo though. It was taken on a cell phone at the lab that did the printing.) However, when the supporting material was removed, the wax structure fell apart - that was a disappointing day...  We've gone back to printing in plastic and are testing different materials for resolution and burnout temps. We're very fortunate to be working with two engineering and printing technology labs (one East Coast and one West Coast) and with Objet (printer manufacturer) to come up with the ideal material. Once again, tests are being printed at a layer thickness of 16 microns. I'm adding some temporary support structure to the inside rear of the pilot which we expect will strengthen it sufficiently for support material removal and shipping as well as provide for better material flow in the investment casting phase. We were fortunate to gain the industry interest in the project because we are pushing the resolution limits of current technology. There are more tests to be run next week. Hopefully one of these days we'll get a winner...



Paul

[Ray Dunakin]

Very interesting! And that rendering is amazing, nothing gives it away as "not real".

[finescalerr]

What Ray said. -- Russ