Ironclad USS Chickasaw, 1/200 scale, from CAD model

[Devin]

I honestly have no idea how long modern printed parts -- meaning those done by SLA or DLP printers -- will last. What I can comment on is my experience with them. I started working with a DLP-style printer, one that uses UV light to cure liquid resin, about 3.5 years ago at my day job at Gulliver's Gate. We built in 1/87th scale: building fixtures, furniture, aircraft and vehicles. So far there has been zero degradation to the printed and assembled pieces, and I have several samples in my possession from the job, unpainted, that look as good now as they did on the day they came out of the vat. My understanding is that the resin used in the SLA and DLP printers -- those used by, for example, Model Monkey, Black Cat Models, etc. -- is very similar to the resin used in casting parts, such as one would find in aftermarket accessories or resin kits. So, it should last as long as those do, one would hope. I would say that the prints, though, should be kept out of direct sunlight as much as possible, especially before being primed and painted, as that'll continue the cure process and can cause degradation.

These prints from Shapeways are printed by a different technology. I know they use some sort of wax substrate, but beyond that I don't know much about it.

[JIM BAUMANN]

Thank you for the re-assuring words..!!

My parts are custom made from Black Cat models...

-- so I hope they will outlive me!

cheers
JIM B

[Devin]

As one of my friends said, when someone criticized his use of 3D printed parts on his models, because they think they won't last more than 50 years: "50 years? Then what do I care? I'll be dead!"

[Devin]

I've drawn all of the armor bolts, 600 of them to be precise, and used the very handy FlowAlongSurface command in Rhino 6 to stick them all to the turret body. I also cut out the gun ports. Pictured, you can see the resulting prints. I still need to add some interior wall detail to the turret, basically separation lines for the curtain walls, and a recess at the bottom for the gun deck. I may also increase the size of the bolts. What I have here is nearly spot-on for reference photos I have for Ericcson turrets (besides the original Monitor), but if they were a bit more visible, it may be nice. I used the Block command in Rhino to draw the original bolt, and then copied it out for the 599 other instances, so I only have to modify one bolt and the others will update automatically.

Also, my trick of shimming the gap between test turret slug print and the hull with a sheet of styrene, then using that thickness to offset the turret drawing, worked like a charm. I've got a very nice friction-fit going on.

Next up is drawing the turret roof. I'm using a paper model of Chickasaw as the template for that, which makes it simple enough. Ideally I'd laser cut the turret top and deck out of .030" acrylic at work, but today marks my first day of furlough due to the Covid-19 crisis, so I don't have access for now. I'll print them here at home and see how they turn out; weirder ideas have worked fine.

[Dan K]

It's looking good.

[marijn van gils]

Great work Devin! Making good use of modern technology!

I would leave the rivets as they are. Once painted, they will be more visible. And you can always make them pop out more with a (pin)wash.

[Devin]

I would leave the rivets as they are. Once painted, they will be more visible. And you can always make them pop out more with a (pin)wash.

Thanks, Marijin! And I agree, a coat of black primer proves them visible enough.

[Devin]

I'm still in the tinkering with the CAD for Chickasaw's components. I'm kicking off this print right now, estimated 4 hours to completion. We'll see how I've done then.

[Devin]

The 1/200 scale Dahlgren and carriage came out pretty good. This will be inside the turret, obviously, which I didn't plan to have visible, but maybe I'll leave one of the roofs removable and detail out the carriages in it with hand wheels, runners, etc.

[Dan K]

That's really nice, D.

[marijn van gils]

Very nice indeed!

Takes me back to this classic by Shep Paine: