Create Perfect 3D Resin Prints by Finding the Optimal Layer Exposure Time

hey gang tim here at cro electronics and today we're finding the optimal layer exposure time so we can make perfect resin 3d prints exposure time is the length of time that uv light shines onto a single layer of a 3d printed model this is a crucial parameter which when dialed in produces awesome crispy results that captures every single detail of an original 3d computer design as a model can have potentially thousands of layers there is no setting more important rowing exposure time is the major reason why resin 3d prints fail or are imprecise underexposing each layer results in serious loss and miniaturization of intricate details delamination weak spots and poor adhesion to the build plate over exposing results in light bleed which scatters uv light too far through the resin liquid resulting in fuzzy details over baked edges and dimensional inaccuracies it is all about finding that sweet spot the best way to home in and find the correct exposure time for your particular resin and printer combo is to print exposure test models the best starting point is the validation matrix printing these matrices are the master key to unlocking your optimal exposure setting the goal here by altering the layer exposure time is to reproduce as accurately as possible this cad model in real life as a quick note a download link for this model is available in the description zooming in close into the stl you can notice on the model that the two sides of the infinity sign perfectly touch in the middle also take note in the bottom section that the bars will fit perfectly if shifted down into the corresponding slots on a correctly calibrated printer resin combo these slots and bars can all be reproduced by a 3d printer but the extreme edges of this section are so thin and delicate that they'll wash away during the ipa cleaning stage and finally take note that there are several pins and voids on the left hand side that become increasingly smaller in diameter by producing several 3d prints of these matrices with different exposure times we can gain the best real-life representation of this stl file once we have produced that optimal matrix we have found our optimal exposure time exposure settings can be adjusted beforehand in any slicing software to do so in lychee by clicking on the 3d printer symbol and then clicking on this cog here where you have access to the exposure setting for your first tests adjust the exposure time found under normal layers a great starting number is using a 2.5 second exposure time this is a good general number for both rgb and mono screen printers note here that the default exposure setting that creality has set is 3.5 seconds resin printers are usually shipped with an exposure setting too high on purpose manufacturers do this so that your first print with this technology will basically be guaranteed to stick to the build plate no matter what the initial resin is chosen once we have printed washed and cured this model with this setting we will then adjust this number for the next matrix print based on the features seen in that printed model so let's get into it by slicing this model just like normal and getting the printer running we're going to talk about burn in layers also known as bottom layers in just a second if you are instead using cheeto box you can adjust the exposure settings here and you can slice your matrix just like this so i brought to the table many validation matrices that have all been printed at different exposure amounts using the creality ldo2h uv 3d printer and the gray creality resin the top section of matrices here all have normal exposure times from four seconds to one second with a 0.5 variation between them this would be a suitable test spectrum for a printer with an rgb lcd screen but to really dial in and find the perfect exposure settings with a monochrome printer it is totally worth it to run tests with a 0.1 second variation the lower section of these matrices are between 1.9 to 1.1 seconds for normal layer exposure each test piece has undergone the exact same post processing and bottom layers jump into the article for those exact details if you want this may look like a lot of testing but this is a very comprehensive collection and these models are very thin and very quick to 3d print for this resin and 3d printed combo a 1.7 second normal layer exposure was deemed to be perfect so allow me to zoom in close to this particular matrix and decipher for you this conclusion a perfect exposure time presents itself when the two halves of the infinity sign in the middle perfectly touch also where the majority of bars in this bottom section would fit perfectly if shifted into the corresponding slots and finally where the same number of pins and voids on the left hand side are present this matrix was produced using a 3.5 second normal exposure setting in it you can see that there is an overlapping of the infinity sign in the center this model also has more pins than voids and it displays bars that will not fit into the corresponding bottom slot sections this is the stock exposure setting that this model of creality resin printer shipped with now let's zoom in on an underexposed matrix this matrix was produced using a one second normal exposure setting here the most obvious sign is blemishes where the model looks shinier in sections this is where the uv light from the printer was not strong enough in the time set to do the initial cure crisply this results in sticky and tacky resin that sticks to the surface of the part resin like this is too hard to remove from an ipa wash but not strong enough to create features or a good surface this tacky resin then gets cured fully after post-processing so it ends up as a permanent shiny blemish on models this matrix also displays fewer pins than voids as seen on the left side and has bars that will easily fit with extra space into the bottom gap sections and on severely under cured examples you will also notice in the center an empty gap between the infinity sign undercured parts have weak spots that can lead to failures and completely underexposed models fall off the built platform bottom layers are the first few layers exposed to uv light in your model bottom layer exposure times are always longer than normal layer exposure times they are exposed longer so that the model can adhere more securely to the build platform a good rule of thumb is to have six to ten bottom layers and to set the bottom layer exposure time to be 10 times longer than the optimal normal layer exposure time considering that i got the best results utilizing a 1.7 second normal layer exposure time with my printer resin combo here i would then use 17 second bottom layer exposure time now it is always the best idea to test normal layer exposure for your own printer and resin combo taking the results from someone else can lead to trouble you could be in a different climate or your printer could have some quirks or the resin batches might be slightly different other people's settings are a great starting point and will save you producing heaps of test matrices but fine-tuning with those test prints is how you get your exposure settings perfect exposure settings can be adjusted beforehand in any slicing software worth its salt or directly through your 3d printer on creality machines this can be done by clicking on the cog in the bottom right of the touch screen then by clicking on each of the numbers you can change or alter the exposure time the bottom exposure time and how many layers of bottom exposure validation matrices are great for checking two-dimensional accuracy but won't supply you with knowledge of a couple of details to make sure overhanging features and overall model stiction to the build platform is still occurring your best procedure is to print a more three-dimensional test object the best model to do this is the make rook calibration chess piece this model has heaps of overhangs from the double helix in the center to the outside walls and internal staircase structure you can verify the settings found from the validation matrix by accurately printing this make rook model with all the text clear and legible and that the overhanging structures are sharp and unbroken once you achieve that you are good to print your dreams my dreams consisted of a gengar with a very special little filler gray all around his body all of that crispy filigree has printed really really well the optimal exposure time changes whenever you use a new printer whenever you fill the tank with different resins or whenever you place contaminants to colorize the resin every time you change your layer height and even over the lifetime of your res printer so it is good practice to run off some of these test pieces in all of these occasions all the models talked about here as well as some other great test models can be downloaded from the article page linked down below it is worth noting all of these tests have been done for a single location in the center of the build platform depending on the quality of the 3d printer the power of the uv light hidden in the resin can be weaker the further you go away from the center of the build platform thus it is worthwhile to run some test prints along the extremities of your build platform to see if there is any degradation of quality also whenever producing these test parts to save confusion make sure to write down on the model itself the settings you use to print them much like i have done here with my printers here pumping out crispy beautiful models i hope i've provided you with all the information to do the same so until next time stay cozy [Music]

Channel: Core Electronics

Views: 1,251

Keywords: Layer Exposure Settings For Resin 3D Printers, how to slice files for resin 3D printing, make custom models printable using slicing software, what is the best free slicing software, creality resin 3D printing, LD-002H, LD-002R, workflow of creating sliced files, is Lychee the new standard?, how to make beautiful resin printed models, how to start making perfect 3D prints with resin UV printers

Id: yhWyQPS6qmQ

Length: 10min 30sec (630 seconds)

Published: Mon Nov 22 2021