New to 3D printed parts

[Boggie]

I wanted to understand how I could incorporate 3d printed parts into my builds so I took the plunge. I am currently working on a couple of SF GMV’s, in particular for this discussion, a Seal team truck with the very complex rear cargo walls. Luckily for me a few Armorama members contribute to the Shapeways company galleries and they have preceded me to designing the parts that I would have other wise had to scratch build. I have asked one person (Ettore Galasso (egalasso on Shapeways)) in particular if they would mind me using their parts as a starting point and he agreed.
I have never used 3d parts prior to this but just looking through the Shapeways galleries there is a lot to choose from. Here is the link to Ettore’s gallery called Priamide Models.
https://www.shapeways.com/shops/galactica-models?li=pb
To be clear, Ettore as with other contributors, are designers and they post their efforts in their own gallery spaces. Shapeways handles all the transactions, prints the parts, ships them and deals with any fallout along the way. You can read all about it on their website. I found that they are very good communicators, they tell you when the parts are ready, when they ship and remarkably they arrived very quickly despite the Covid craziness and the US/Canadian Border restrictions. If all aftermarket companies were as professional as Shapeways we’d all be ordering more.
My very first experience with Shapeways was with fellow Armorama modeller Matt Lease
https://www.shapeways.com/shops/downrangeproductions1-35th-scale
I asked him if he could make me some radio/electrical connectors in 1/35th and he did so I bought them from his gallery. When I got them they were so small I can hardly see them let alone use them, but they are exactly what I asked for, they are still on this gallery page for anyone else in need of such things.
I ordered some other parts at the same time, some from Ettore and some from Peter Samofalov as well. The way that Peter displays his objects on his gallery are more seductive for me, where as Ettore’s are computer generated CAD images, both are excellent as you can rotate them in 3d space to see what it is they include and what they don’t.
You have to understand some things about this process before you start snipping off sprew gates and that is cleaning the part, not an easy task. At the printers they clean the parts to remove the wax that is used in the process, I’m not sure I understand how wax comes into it but be careful when you receive your parts. I used an old Crock Pot to cook the parts in a controlled hot water bath which did nothing. I added detergent still nothing. I searched the web to see what others are using and that just got more confusing, I did not want to wreck the parts by doing the wrong thing nor kill myself with toxic solvents that I didn’t know how to control. I had some Franmar Soy based paint stripper so I tried that diluted a bit with water and it worked. In some instances I had to do it a few times but I think if I applied it and then put the part in a zip lock bag and left it for a while I could have done it in one go. Here is a review.
Soy Gel Paint Remover How-To and Review - Less Likely To Eat Your Flesh
Using a bamboo skewer or a tooth pick helped remove some wax hidden in detailed parts and it didn’t scratch the parts. I washed it all off with hot water and detergent and I was ready for the next part. If you’re the type that gets upset with excess flash on your parts you will not like the current generation of 3d printed parts.
Ettore explained to me that the amount of banding or printing lines depends on the orientation of the part in the printing process, perhaps he will post the explanation here for all of us to share.
What I found was that if the designers would not put tiny surface details on the flat surfaces they would be easier to sand. They could have small orientation pin holes so we could drill of the places for bolts and rivets could go and the designer could include a sprew of nuts,bolts and rivets for this specific application. Also regarding the rear walls of the seal trucks, they are incredibly complex with many layers of details and so small that the only tool I had was a micro chisel to get down into the surfaces to remove the banding. I asked Ettore if such complex parts could be designed in separate layers and then we could put them together but there is a thickness tolerance that the parts must be designed to in order to print.
A primed sprew after cleaning

another piece of the set that had been primed but then scraped and sanded to remove the banding.

I thought that by using Alclad black primer with micro balloons it would help fill in the “valleys” and level off the surface…nope.

Then I tried using Woodland Scenics gloss water medium. The nice thing about this is that it is self leveling and you have time to apply the material. I filled each shape withe acrylic gloss, the water evaporated away leaving a film over the intended surface. I am not sure I am any further ahead but clearly some areas are smooth. My next attempt will be with Mr.Surface 500 and lacquer thinners.

Be aware that the shapes are the size of my smallest brush or the head of a toothpick.
I think for pieces like this photo etch is still the better solution BUT the interest in GMV’s isn’t as high as they once were, everyone is chasing the latest and greatest but I do still see this type of complexity on M-ATV’s. I am sure that injection molding can do this type of detail.
i will leave this here with an illustration of a weapons ring that is one of Peters.

I don’t think I will be able to use this beautiful piece of design because the printed piece is so heavily banded, the details are so close together that to clean then with files and sand paper would destroy them in the process. Perhaps I will remove the detail and then re apply the details with resin bolts. The parts are remarkable but the time and labor to achieve a suitable surface is daunting. Is the technology out there to resolve the banding issues, how does Live Resin achieve such remarkable resin products?
Regards
Boggie

[Biggles50]

Live Resin, Model Monkey, and Reedoke, among others, use a totally different tech. They incorporate MANY printed support posts instead of wax. These support posts sometimes form a complete network under the part. Connection points are tiny and easily removed but there can be dozens on complex, or larger parts. However, I’ve had some parts from Model Monkey, and after slight clean-up, are so smooth they look like they were cast resin!

[Boggie]

Biggles50
Many thanks for this I will check them out. I have purchased Live Resin before and I’m totally amazed by the quality of casting they do. I don’t know Model Monkey or Reedoke but I have seen discussions about printing where they use supports, I’d like to try them. Model Monkey certainly has a diverse selelction of printed parts.

About Model Monkey® 3D-printed Resin

Thanks

Further to my previous comment about Ettore, I quote his message about orientation.

"You are highlighting one of the main cons about 3D additive printing: printing layers; I try to minimize this negative effect by using orientation of the parts; here an example of a part that was oriented in vertical:

you can see layers in the vertical surface and nothing on the top surface; in a case like this you have to choose which face of the part you want to give priority."

By the sounds of this then the designer chooses the orientation when he submits his/her designs to Shapeways.

[Model_Monkey]

Some thoughts that may help. The tech Shapeways’ uses to produce its “Smooth Fine Detail” products is an older type of 3D-printing. Like any type of printing technology, it has is advantages and disadvantages. Shapeways’ 3D printers and resins are very expensive and are made by a company called 3D Systems. (Model Monkey products are made in printers produced by Formlabs which use a very different technology.)

Shapeways’ “Smooth Fine Detail” plastic is acrylic plastic, chemically related to Plexiglas. Paints and cleaners that work well with Plexiglas will work well with Shapeways’ 3D-printed plastic. This is one reason why acrylic paints work best with Shapeways’ acrylic plastic. They are chemically compatible.

Shapeways’ 3D printers use a waxy material to support overhanging features during printing. Since the models are not cast in a mold or use plastic that is injected into a mold, there must be some form of support to overhanging features during printing. Shapeways’ printers extrude both plastic and the hot waxy support material simultaneously during printing. A laser then cures the liquid plastic forming the model. Other printers typically create supporting sprues that must be cut away later. In the rendering below, the model is represented in red, the supporting waxy material in yellow,

The surface areas in contact with wax are shown in orange. Anywhere on the model that the plastic comes into contact with the hot waxy material during printing will be rough - the orange area. That’s because the hot wax slightly deforms the plastic surface when they come into contact with each other. This is one reason (among many) why the model’s orientation in the printer matters.

After printing, Shapeways places the model in a low-temperature oven to melt away the supporting wax. The model is then placed in a heated oil bath to remove stubborn waxy bits. The model is then washed in water and detergent to remove the oil. Despite all these cleaning efforts, some wax may remain.

Smoothing Shapeways’ models’ surfaces is difficult. One product that is very useful in smoothing rough surfaces is a relatively inexpensive “air eraser”. An air eraser, typically used to etch glass and other surfaces, looks like an airbrush but emits grit rather than paint. Think of the process as kind of like sandblasting on a very small scale. Modelers use common household baking soda as the grit. Baking soda is cheap, plentiful and non-toxic. With careful use, baking soda is generally soft enough not to damage the model but hard enough to smooth surfaces. Using an air eraser is also helpful in cleaning models and removing unwanted paint without damaging the model.

There are many quality air erasers on the market. Harbor Freight sells air erasers for less than $30 USD. Here’s their model:

Here are some tips for working with models printed by Shapeways:

1. Keep your Shapeways models in their plastic wrapping until you are ready to paint them. Shapeways’ white acrylic plastic may be harmed by prolonged oxygen exposure.

2. Shapeways’ white acrylic plastic 3D-printing process uses a waxy support material during printing and warm oil to clean the model of wax after printing. Clean any residual wax and oil from Shapeways’ white acrylic plastic with isopropyl alcohol or warm water with mild dishwashing liquid like “Dawn”, “Fairy”, “Joy”, “Simple Green” or baby shampoo (no conditioner).

3. Place your Shapeways white acrylic plastic models in direct sunlight or under another ultraviolet light source for a half hour or so to ensure all of the plastic is fully hardened. Enamel paint may not harden on Shapeways’ white acrylic plastic if the plastic itself is not fully hardened. Fully hardened Shapeways acrylic plastic is translucent white, not yellow, and has little or no odor. If your model is yellow or has a strong odor, uncured resin is present.

4. Acrylic primer and acrylic paint for plastic models work best with Shapeways’ white acrylic plastic. You can use enamel paint but the white acrylic plastic must be fully hardened before painting.*

5. Cyanoacrylate “CA” glue works best with Shapeways’ acrylic plastic. Epoxy works, too, as well as any cement that works with Plexiglas. Liquid cements for use with injection molded polystyrene like Tamiya Extra Thin and Testors Liquid Cement will NOT work with Shapeways’ plastic.

6. Do not use methyl ethyl ketone (MEK) as a paint thinner for airbrushing Shapeways’ plastic. MEK is known to cause a white powdery residue to form over the paint after the paint has hardened. The residue is a nuisance to remove.

7. Do not use acetone or acetate to clean Shapeways’ plastic. Acetone and acetate are known to melt 3D-printed acrylic plastic.

Hope this helps.

*In order for Shapeways’ 3D printers to extrude resin, the resin must be liquid. Resin naturally hardens instantly. So to keep the resin in a liquid state, a chemical inhibitor is added to the resin during its manufacture. The inhibitor is destroyed by ultra violet (UV) light. When the 3D printer’s laser, emitting UV light, strikes the resin, it destroys the inhibitor and the resin naturally hardens very quickly. But the inhibitor can keep enamel paint from hardening, too. So if there is any inhibitor present in the model, and you use enamel paint, you’ll end up with a gooey mess. Placing the model in direct sunlight for a half hour or so will ensure that all of the inhibitor has been destroyed. With no inhibitor present, enamel paint will harden on your model.

[Boggie]

Model Monkey
This is an excellent tutorial, thank you for taking the time to explain.
On my first Shapeways order I stuck with the lower priced option but on the subsequent order I paid for the higher priced version thinking that the “banding” might be less pronounced but it was the same. On one of the sets I ordered the designer had “bundled” two M1165 roof’s with associated accessories but one was white and the other was yellowish, I didn’t know why that was but now I do. I also had never heard of the mini sand blaster brush I will check to see if I can get one in Canada.
I will post results of my experience with the 3D printed parts I have, I will follow your advise on prep and paint as well.
Regards
Bill

[Boggie]

A really good Armorama discussion on 3D printing from 2015, how time flies.
https://archive.armorama.com/forums/234938/index.htm
It seems that the issues back then are still issues today, too bad.

[Biggles50]

@Model_Monkey ; Maybe you also make a statement on the printing tech you use, and how it contrasts with that of Shapeways, etc. I’ve bought a few of your gray resin products and, with the exception of the numerous support posts to remove, found them really excellent … Shapeways - not so much!

[Model_Monkey]

Sure and thanks for the compliments!

The 3D printers I use are based on a technology called stereolithography, or “SLA” for short, which uses a laser to harden liquid gray resin in a tank. Shapeways’ printers use a different technology where resin is extruded through a nozzle then hardened with a laser.

I use Formlabs Form 2 and Form 3 printers. The Form 3 is newer and uses a different mechanical process than the Form 2 but they are both SLA printers, using a laser to harden liquid resin in a tank.

My printers don’t use waxy material to support overhanging features during printing. Rather, physical supports which look like sprues are created that support overhanging features.

Here’s a link to a 5 minute video to show you how the Form 3 works: From Design to 3D Print With the Form 3 - YouTube

The main advantage of SLA is that SLA produces very smooth surfaces. The main disadvantage with SLA is that physical supports are needed which must be cut away by the modeler. Support removal can be difficult.

Generally, model surfaces are very smooth right out of the printer. Since no wax or oil is used during printing, there is no wax or oil cleanup needed. Here are some models as they look upon printing completion. No surface smoothing has been performed on these models. The models were removed from the printer, cleaned in a mechanical bath containing isopropyl alcohol, then air dried, then placed in a UV light booth for 30 minutes for final curing.

With a well-researched design, SLA can produce products that are far superior in accuracy and detail to the parts found in some injection molded kits. Here are some comparisons:

Top: Model Monkey 1/350 USS Arizona turret. Bottom, Mini Hobby Models 1/350 USS Arizona turret.

Model Monkey 1/350 USS Arizona superstructure with Mini Hobby Models 1/350 USS Arizona superstructure (all parts both models dry fit).

1/350 scale Italian heavy cruiser Pola turrets, Model Monkey on left, Hobby Boss on right:

1/32 scale Bf 109 spinner, Model Monkey on left, Trumpeter on right.

Thanks again and kind regards.

[Panzer_modeler]

@Model_Monkey Just wanna say I got a buncha your Fletcher 1/350 stuff and loved it! Detail was amazing and the clean up was so easy!

[Recon22]

Yes mate, I feel your pain…I am giving up on the 3D printed items I purchased from a shapeways store as I have tried to perfect my 1/35 Japanese guns that I’m working on for a Pacific Dio. Gave them a warm detergent bath and then Acetone solvent to clean them again, can’t sand too much due to the small/ fragile detail. So will now after a base coat of grey primer I will try to fill the banding with Vallejo paints. Just can’t get that nice detail of the finer parts as you do on a plastic/ resin kit…anyway some photos attached of the banding and problem areas.

[Frenchy]

Looks like you could almost used them for a Truk atoll underwater dio…

H.P.

[Amegan]

Interesting article, getting rid of banding effects is a problem I have with filament printing. Two tips in here that could be very useful where a smooth surface is needed. I have found limits with filament 3D printing and some parts that are easier to scratch build, either because I can’t draw them, (clinker built 10ft dinghy) or because building is quicker and easier than printing (LCT5 hull). I find 3D printing most useful for repetitive small items (ventilators, guns, lockers) especially odd shapes like cones and gun mounts, gears. My parts are really only as good as the amount of work I am prepared to put into a design, like any scratch build project.

[Vicious]

I think that for static modeling where detail is everything the best technology is resin printing, especially now that the price of high resolution resin printers has dropped considerably, I paid my home printer $ 200 and it has a detail of 50 microns per layer, in theory I can reach 20 microns but I haven’t tried it yet, the detail is impressive and the layers depending on the model, scale etc it is difficult to see them, and in addition the printing speed it is much higher than a filament, for the moment I’m learning to print Stl files already made that are on the web … one thing at a time

[Recon22]

Ha ha Frenchy…my wife said the same thing seconds before your reply with the underwater jap gun image. Anyway, I have been hoping that a 1/35 plastic manufacturer would make these little guns. I know Yellow Cat and Pit Road use to make smaller arty pieces apart from their 75mm gun. One day…!

[Amegan]

I think there is a place for both, but I have stayed away from resin for two reasons, print size and domestic harmony. I have stayed off printing ABS for the same reason. Smells would be a no go and I have no outside workshop.

[Biggles50]

Didn’t Fine Molds release a small Japanese infantry gun/howitzer with crew a few years ago?

[Frenchy]

H.P.

[Boggie]

MM
Night and day. How would I love to not have to scrape wax and sand banding lines before I get on with my projects. Your Grey resin looks absolutely stunning. When are we going to be able to get the same detailed parts that are currently available on Shapeways? Will the CAD files work to generate the same parts and if so what is topping the designers from working with Model Monkey?
Thanks again for your illustrations, now I want to see some GMV parts done this way.
Great discussions, I am learning.
Boggie

[RLockie]

You can already produce parts at home on resin printers which have superior resolution to Shapeways parts. You just need a way of designing them and to have good enough data to turn into CAD drawings.

Once you can do that, your horizons expand massively. There are decent CAD programs which offer free licences for hobbyists to get you started and hours of free tutorials on YouTube.

[Model_Monkey]

Shapeways attempted to offer SLA printing a few years back with printers very similar to mine. The problem is that the supports have to be designed, too, at least to some degree. That effort has to be done by a person familiar with the requirements and limitations of the actual 3D printer. Normally, customers don’t have that familiarity so the work can’t be done by customers. So, Shapeways had to do that work in house. Support design can be very labor intensive and require test prints to ensure the model is printable at all. Customers not understanding the requirements and limitations of SLA printing frequently objected to where Shapeways put the supports. It became too labor intensive, too time intensive and too costly for Shapeways so Shapeways discontinued offering that material after a short while.

Shapeways does offer another kind of SLA printing, called “SLA Accura Xtreme”, but its characteristics are generally unsuitable for small scale models. It can’t produce fine details. Here’s a link to that material’s design considerations: Shapeways: SLA Accura® Xtreme™

Other printing companies do offer SLA printing. One of the best is Collapse Industries in Florida, currently shut down due to Covid (Covid badly affected 3D printing companies world wide). To find others, Google is your friend.

I regret that I am not staffed to print designs by others. There are a host of issues that come with that, from providing dedicated design and customer support services to guide customers in creating a printable model, design supports for submitted models, and hiring legal counsel to sort out copyright and trademark issues of models submitted by others. Resolving all of those issues incurs a considerable cost which, frankly, isn’t affordable.

So for those with models from Shapeways, you might give an air eraser a try.

For those interested in your own 3D printer, excellent, affordable SLA printers for hobbyists do exist. Anycubic Photon and Elegoo Mars are worth looking at.

And I concur with RLockie, you need to have some good CAD skills and good design software, too, in order to design models. Youtube does have loads of tutorials to learn from scratch or improve the skills you may already have. It can seem overwhelming at first but you are likely to be pleasantly surprised by how enjoyable and fast the learning is.