Some recent 3D printing work

[SandiaPaul]

I was asked to show some 3D printing work by Russ. I really am a live steamer with aspirations to do some other modeling...but there is only so much time! I got a printer mainly to print parts and ultimately cast them for live steam work. But I also wanted a printer that could do a decent job for small model making projects. As a member of the New York Central System Historical Society I get asked regularly by the editor of the NYC Modeler online magazine to contribute. I am still in the learning phase of the printer and I thought sure I can do something. I have had in mind to build a model of a crossing watchman's tower for many years after first seeing it on the cover of the Society's publication. For those that are already into 3D printing you know that there is a learning curve. And for me at least it was(is!) pretty steep. Lots of variables and they are all playing together. Luckily I had a drawing of the tower so building the model was easy. I've been using Autodesk Inventor for years in my work. Here is a prototypes photo or two and a screen shot of my 3D model.

BTW, the photo sizing thing and posting is quite a "challenge" to put it mildly. I just can't seem to get it...

[SandiaPaul]

Another prototype picture

[SandiaPaul]

Screenshot of my 3D model

[SandiaPaul]

First efforts were a bit frustrating...as you can see. The blue resin I abandoned, Siraya Tech Blu, some seem to get great results with it, but I just could not get a decent print. The support legs were just too fine to get anything to print.

By the way this is in HO scale!

[SandiaPaul]

I wound up making the legs from actual rail, as were the prototype ones. I annealed the rail and made a jig to bend the rail the "hard way" and printed a base piece the rails were press fit in to keep their alignment.

One picture shows a test fit of the 3 main pieces. Note that many people try and print models "all in one go", I find I get much better results as a kit of parts. It is easier to deal with the peculiarities of each section one at a time. You can design in features to help locate parts for ease of assembly.

Also I have tended to print my parts "wrong", most people, and indeed the printer manufactures say to print parts on an angle and using supports. Sometimes that is the way to go but I had much better results printing flat on the build plate and using no supports. I actually added the cross supports that go across the structure that were later cut away.

You can see some window sections on the build plate right after they have been printed and washed in IPA. I got much better results that way.

[nalmeida]

Great work Paul, I also use the Blu in my projects but this resin, although very tough, is not suited for thin pieces and sharper details. Liked you idea of doing the legs lyke the prototype.

Despite being a outstandig tool I don't see 3D printing as a solution for all the problems.

[SandiaPaul]

Here is the final result...btw I HATE painting...and this forum has an embarrassment of riches with top quality painters...so forgive my efforts.

I will be happy to go into more details and answer any questions about 3D printing anyone may have. It is a great process and like anything it has its limitations. I can tell you one thing though...while I do have some modeling skills...there is no way I could have made that octagonal roof by hand, at least not as good as the 3D print.

[finescalerr]

What kind of printer did you buy? Its resolution seems pretty good because your HO model's detail appears equal to injection molding.

I've never tried to 3-D print anything but, as I've analyzed how our experts work, it might have been appropriate to print the windows, ladder, and octagonal roof as separate pieces. The walls and trim might have been about as quick to build from styrene. Your use of rail for the legs is perfect (and probably something I'd have asked somebody to help me with!).

In other words, you have the right tool and you are getting good prints but may have to use the printer more specifically.

Russ

[SandiaPaul]

The main separate pieces are, roof, window section and the lower board and batten section. Printing these separate was the only way I could see doing it to get the desired results.

The ladder is a brass photo etch I bought. I maybe could have printed it, bit it was easily available and the right size. In O scale I would have tried to print everything.

I bought a Zortrax Inkspire. What in the photography world would be called a "prosumer" unit.
I'm working on a N scale NYC caboose now...wish me luck!

[finescalerr]

All of us will be very interested in what you turn out and in what you learn. Your printer is up there with the most desirable for serious hobbyists and its resolution appears to be outstanding. If you can master your printer then there's hope for the rest of us. -- Russ

[Bernhard]

Personally, I only use 3D printing for parts that I can't make myself. Typically, these are replicas of castings, among other things. I have these parts printed by a service provider, because there I can choose the optimal process and the optimal material.
But I find printing myself an exciting facet of our hobby where you can learn a lot.
Thanks for sharing your experience.

Bernhard

[Ray Dunakin]

Very cool little structure, with lots of character. Nice job on the model too!