SLA Printer Full Guide

How it all Works

If you’re new or interesting in starting 3D printing, you’ve probably heard that you needed to support your resins prints. But what is this, and how is it important? Today’s we’ll explain this core principle along with how it all works.

Resin prints are created using multiple layers of exposed resin and while this process can be relatively fast when compared to other’s, it does have some important considerations. Everything needs to be connected to the build plate in order for a successfully 3D print to occur. This is mainly due to the fact that the resin is only partially cured, requiring it to be attached to the remaining structure to prevent it from becoming stuck to the FEP sheet or floating freely within the vat. These stuck portions and floating particles can cause serious damage to the LCD screen if not taken care of. In a lot of cases, this will require their removal prior to continuing onto the next print, which results in lost resin as well as time.

Any portions of the print which aren’t connected to the remaining print structure or build plate are known as Islands. Examples of this can be clearly seen in the photon validator or on the layer preview for Chitubox. In this case, I’m showing you a supported and unsupported version, so you can get a better idea of what to look for.

When a print is completed, the material is only partially cured to ensure that all the details are present and not washed out from overexposure. This will often mean that it’s more flexible, therefore these regions need more support to prevent them from flexing or distorting. Portions which hang or extend outwards are known as overhangs. Take special care when dealing with these regions, since they will often need quite a few supports to ensure that the structure prints properly.

Another big consideration is that the print needs enough supports to keep it attached to the build plate. The main reason for this is that a large amount of suction is created when the FEP sheet separates from the build plate. My video on “How an SLA printer works” goes through this in more detail, but you need to know that adding supports is intended to overcome those forces. How a user orients their print, will often affect how many supports are needed, as well as the amount of suction that created within regions of the prints. In these two examples, there’s a large amount of suction created on one version while the second one has a lot less, which is due to their orientations.

The weight of the printed object will also contribute to the number and type of supports which are needed for a given 3d print. Since prints are done upside down, they have to contend with gravity as much as they do with the suction forces. This is often the leading reason why a print will be hallowed out prior to being sent to the printer. By removing any excessive or unwanted resin in the printing process, a user can save on material while maintaining great overall results.

Now that you understand the importance of supports in resin printing, we’ll go over how to set up basic supports.

Important Notes

  • Overhangs
  • Islands
  • Orientation
  • Weight

Recommended Articles

Testing results for Conjure Rigid Resin by Chitu System
SLA Printer Full Guide

Testing Results

So is the “Conjure Rigid” by Chitu System any good or not? Well, we’re going to take a closer look at it today. I was sent this product free of charge, but no money has exchanged hands, and they have no say in what goes into this review.

So although I did receive this almost a month and a half ago, I wanted to take my time to do a proper review of this product and really test out their claims. So I tested it for miniatures and functional parts and discovered some things you’ll want to keep in mind if you pick this up. While unboxing this product, I did have some concerns about the design of the bottle. Inside the cap there is an additional seal to prevent leaks, however resin gets easily caught in the edge of the rim when pouring. If this isn’t cleaned properly before being stored, it can start leaking or dripping along the edges of the bottle. Now, so long as the bottle isn’t exposed to UV light this isn’t a huge issue, but it can become permanently sealed if it cures. It is for this reason that storage will be very important when dealing with this product.

The overall viscosity is thicker when compared to most standard resins, however I find this to be consistent with most of the industrial resins that I’ve used in the past. Similarly, the black version is much thicker than any other colour, so ensuring that you use it in an area that’s above the recommended 25°C will help you achieve better results. This product smells extremely strong in comparison to other products and although this isn’t a measure of the level of toxicity, I would recommend using proper ventilation practices as referred to in my safety video.

Chitu Systems did a great job about making the print settings available on their website, and for the most part it was pretty much plug and play with the settings that were provided. The one issue that I did have, was that, due to the flexibility of the material. I did have to modify my support settings to account for this, especially when printing small, detailed prints. So how did I end up changing these to work with this resin? We’ll First off, I added much thicker supports on the main regions of the model which would properly anchor it to the build plate. I then increased my lighter supports middle diameter and top lower diameter, so they would stay more rigid. I unfortunately found that I couldn’t rely on the automated support when it came to smaller models due to them flexing during their printing. While this was more time-consuming, it did mean that I could ensure the supports were far enough not to get stuck onto the model. I also increased the bottom exposure of the first layer, which helped keep the model attached to the build plate. Once again most of these issues were more prominent with the black resin, and although I’m unsure as to the reason it’s something to be mindful.

This resin does come with explicit instructions to use preferably 95% isopropyl alcohol when cleaning. While I can’t confirm this to be the case, since I changed cleaning solution at the same time. I can say that I had more difficulty cleaning the black resin, which is most likely due to the higher viscosity or thickness of the material. It should also be noted that I clean all of my prints with a two container approach, since I’ve found this to work much better overall.

Now, although this material does remain flexible after it has just cured, I found it still sanded and cut quite well. So cleaning up the models prior to painting was fairly easy once cured. While the parts can still break just like any resin, I did find that the shape of the part made the biggest difference in this regard. All the weapons that I printed for my models stood up well to being bent after having just cured, while the tips of the tails keep breaking off. Now, to be honest, this is more about the shape of the design than anything else. Essentially, whenever you have a shape this, you tend to create an area where tension and stress can build up at the pinching point. This in turn makes them more likely to break. So when removing support material, those will be the areas that need to pay attention.

One property of UV curable resins is their tendency to become more brittle over time, and this is important to be aware of when using this material. One of my favourite resins by another company has this same issue, and after about 2 weeks I generally find that the resin has stabilized more, at which point I can better test the fragility of the material for the application. This resin is no exception in this regard, and became much more brittle after the two-week period. While I don’t have the proper methods for measuring shrinkage of a material, I am assuming that there is some additional shrinkage that may be occurring as the resin becomes more brittle. So depending on the application, this is something that should be tested prior to beginning production.

Important Notes

  • Needs to be printed in temperature above 25°C
  • Becomes more brittle over time
  • Is flexible
  • Has a strong odour (use proper ventilation as described in this Article)
  • High Viscosity (very thick)

© Yarkspiri Fantasy Art

The full playlist can be found at this link here. https://www.youtube.com/embed/videoseries?list=PLwEQCqKC1zEd2kXuk-AACjrlJVTHIhve4

The Story

Under my iron rule, I was to be betrayed by those who could not accept my greater vision. With a name that was stricken from all records, I now lay nameless and have vowed to regain my former grandeur.

By Today’s measure, I may seem overly elaborate, but within the coldness I hold my dark secret. My blade holds hungering crystals that will prey off the souls the moment they may be struck down. Every living creature contains both good and evil, but many choose to side with what the best suites their own needs. Whether it’s helping those around them, or stomping them out because of their fear, all contain an edge of darkness.

In those dark moments of hidden memories, I nibble or feast. It is this poison that drives me forwards and gives me strength, but when I’m not fed enough by my wielder, so begin the true test. Only strong wills may contain my greedy hunger because otherwise I become the master puppeteer. As I begin slithering my control within their mind, little do they realize whose decision it was all along.

Those who are wise and just rarely need worry about my gaze, for they hold little interest to me if they cannot be corruption from within. Oh, what joy I take in eroding the mind of another until they see nothing else but what I choose to feed them. So thine does their will become from my insensitive tutelage, that before long, I am all that remains within the mind. By this point, I am the wielder and master of this vessel, and I’m now free to do as I will.

How to do your first resin print
SLA Printer Full Guide

Instructions

Well, in today’s article we’ll be going over what you need to know, so you can start printing as soon as possible.  

For this video, we’re going to assume that you’ve already levelled your build plate according to your machine’s instructions. And since calibration can take a while, that’ll be covered in a more in depth video later on.  For now, however, we’re going to use the recommended manufacturer settings for the resin that you purchased, since in most cases this will be a good starting point.

So to start things off we’re going to need an epic file to 3d print and these come in a variety of formats.  The most common of which is the SLT file format that you see here.  This format has remained pretty much unchanged from its initial commercial adoption in 1987. Other common file formats include OBJ and 3MF and are compatible with most slicing software packages.  I like many other creators online, I get these files from a variety of sources or make their own, but the main ones are Thinginverse and GrabCad. In order to take this files and print them, they first need to be compiled into a language that the printer can understand and this is where software like Chitubox, Prusa Slicer, lychee and many more come into play. These pieces of software turn the 3d objects into slices, which can then be printed in steps by the 3d printer of choice. Unlike an FDM printer, LCD printers print one full layer at a time, making it generally more efficient to fill the build plate.

Before opening up a 3d file, you’ll first want to set up your machine settings and get it calibrated. In Chitubox the free version, you can do this by going to “Settings” + click on the “Add New Printer” button and select from either a preexisting profile or set up your own instead. You’ll then need to set up your print settings for your material. Most resin and 3d printer manufacturers provide some suggested settings which are available online and while these are a good starting point you’ll most likely have to tweak these to get better results.   Each resin, even if it’s from the same manufacturer, will have its own settings and each 3d printer will behave slightly differently, which is why these settings are generally just a starting point. 

The slicer will allow you to see your model in a virtual representation of your build plate where you will be allowed to manipulate its dimensions, orientation and much more. Once we’ve imported the file, we’ll need to orient it so that it has enough support from the peel forces. These forces are created when the build plate lifts and away from the FEP sheet. A common practice is to hollow out the model to save on resin, and while this does help quite a bit, it also increases the peel forces by create a pocket in which the pressure can build up.  It’s for this reason that we’ll need to do two things with this model before we can start printing. First, we’re going to orient it in such a way as to reduce the amount of forces being applied while also reducing the amount of support that’s needed. While this can normally be a 45-degree angle, this will depend on the size and shape of your model. For example, the custom key caps that I make have very little peel force being applied, and I can actually print them almost entirely flat. My “Peel Villain however requires it to be printed at an angle, even with the giant drainage hole. To keep the print attached to the build plate, we add support material. These supports have a crucial role in making sure that every point on the model is connected to the build plate to prevent the prints from becoming dislodged.  Printing unsupported portions could damage your printer by puncturing the FEP sheet or damaging the LCD. If you hollow out your model, you’ll also need to consider at which points to add your drainage holes. The holes help relieve the pressure that builds up within the model itself, while also allowing excess resin to come out during the cleaning process. 

With our files properly set up, we can now begin slicing them into a format that our printer can understand. If you’re using an existing configuration, the correct file format should already be selected. You’ll then be able to save your file onto a USB drive or send it to your printer via Wi-Fi. After that, it’s a simple question of selecting your model and printing it. Before you print your files, you’re going to want to make sure that you don’t have any debris that’s left over in the vat, since these could easily damage your LCD or FEP sheet. Once you’ve finished printing, you can then begin cleaning your print and curing it. It’s much easier to clean the resin print with isopropyl alcohol or an alternative resin cleaner, followed by the removal of the support material. At this stage, you may notice that your prints are still not quite solid, and this is because they require some additional curing. You can either cure them in the sunlight or use a UV curing station for this purpose. Either one will work.  If you want to know more, I have a PDF guide for resin printing that’s available on my website.  This guide includes diagrams and additional information on the whole process to make it easier for newcomers.

Personal Notes

Article notes

  • Find and STL, 3MF or OBJ file to print
  • Install + Setup Slicer for Printer
  • Import file
  • Orient + Hollow + Support Model
  • Slice File + Save to USB
  • Print file on Machine

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© Yarkspiri Fantasy Art