How to 3D Print Miniatures With a Resin Printer

Curtis Satterfield, Ph.D.

When I first started 3D printing it was because I wanted to print terrain and miniatures for my tabletop games. You may be wondering how to print miniatures for your games or simply to paint for display. In this article we will examine the process for 3D printing miniatures on a resin printer.

Steps to 3D printing Miniatures

Calibrate your resin
Prepare the model
Use appropriate settings in your slicer
Print the Miniature
Remove the Miniature from the build plate and wash
Let the Miniature dry and then cure
Sand and fill
Prime
Paint!

The basic steps to printing a miniature are like any other resin 3D print. The main difference is that with miniatures there are usually lots of tiny details that you don’t want to lose during the printing process. By following the advice and steps below you should be able to print great minis with your resin printer!

Calibrate your Resin

The most important factor in getting good prints from your resin printer is the layer exposure time. Over or underexposing your prints will result in losing details on your model. You need to ensure that you have the proper layer time dialed in for the resin that you are using. Most manufacturers have a guide on exposure times for their resins. And many printer communities have online spreadsheets showing exposure time for different resin brands on a single printer model.

Using data from the manufacturer or an online guide is ok, but I recommend running a resin calibration test to find the optimal print time for your printer. I use the Multi Printer Resin Exposure Test found here. In short, you will use 3 files from the Git repository. Two files are G-Code files that are needed to configure your printer for the test. The third file is the actual model that you will print to calibrate the resin.

The test will print a small card that has several images and numbers on it. Across the top of the card will be numbers showing exposure time in seconds. Under each number will be a set of symbols that you use to compare and determine which layer exposure time is right for the resin you are using.

The image below is a calibration test I did for Elegoo standard on my Elegoo Mars. The exposure times are outlined in red and the calibration images are outlined in magenta. This picture skews the results a little as looking at the print in person 7.5 had the best balance while on the picture 10 appears to be a better setting. Ideally, you want the positive and negative spaces to be equal on both sides of the column.

Resin print card I made on my Elegoo Mars

It takes a little bit of time and effort but once you calibrate your resin you don’t need to do it again for that bottle of resin. After calibrating your resin and you know what exposure time to use for your resin you can continue to the next step.

Prepare the Model

Next to having correct exposure times for your resin, preparing your model properly will have the biggest impact on print quality and success. When printing with a resin printer the model hangs upside down and the model pulls up and out of the vat as it prints. The suction force of the resin releasing from the vat can cause distortions in the print. To avoid this, you need to support your prints. Many models now come pre-supported by the artist. If you don’t have a pre-supported model you will need to add the supports yourself.

Pre-supported model on left versus unsupported model on right.
Models were purchased as part of the Bloodfields print and play game available on MyMiniFatory.

The first thing you will need to do is determine how to orient your model for printing. Remember that your model will be supported from the build plate. You want to avoid facing highly detailed areas like the front of your model down towards the build plate. In the image below you can see that the with the model facing down several supports will be used and cause damage to the front of the model.

Supports connected to highly detailed areas such as the face will cause noticeable damage on the finished model.

You may be thinking, ok so we flip the model on its back and hide all the ugly marks from the supports. That might be ok if you were only going to look at the front of the model. Also, if you are serious about painting your miniatures to a high level, the damage on the back of the model will drive you crazy. I recommend tilting the model maybe 15-20 degrees towards its back as shown below.

Good model orientation allows for optimal support placement

Now all the contact points from the supports will be in less noticeable areas. Most of the model is support free and will look great when finished. I do need to note that for the above images I used auto-supports for a quick demonstration. Auto-supports don’t do the best job at properly supporting your model and you will need to spend time learning how to properly support your models manually.

Learning to manually support your models will take some time and effort but will be worth it for beautiful prints. You want to aim for the least amount of supports on your model that will still provide the structure needed for a successful print.

To being you need to identify where supports are needed in your print. The easiest method in ChituBox is to look up through the build plate at the bottom of your print. Make sure you are on the supports tab as shown below.

Now if you rotate your build plate view so that you are looking up through the build plate you will see areas of red on your model.

Slowly drag your cursor up and you will see a line pass through the model. Look for the first points where the black line appears on the model. Those will be the places you want to anchor the model with heavy supports.

Circled in white the black lines on the model indicate where the first layers will print. Be sure to use heavy supports to anchor these areas to the bed.

Continue adding supports to the model using heavy for anchor points where the most force will be applied as the model prints. Because we are connecting to places that will have the least visual impact, don’t hold back on using the heavy supports. You want to ensure that your print will be anchored well and won’t fail while printing. Once you’ve got the model well anchored switch to medium and light to connect any small islands.

An example of an island that needs support.

Islands are areas that are not connected to the current model and would print with nothing to connect with. Be sure to use supports to connect all the islands you find as you slowly drag the cursor up the model. Rotate the model and look for islands from many different angles.

When placing supports be sure support pillars are not too close to the model. Due to light leak from the LCD screen and inconsistencies during the print process your support may end up bonded to the model.

If you find supports too close to the model use the edit support feature and click on the tower. Then Drag the tower away from the model to allow more space.

At this point you might be tempted to use auto supports to save time and effort. Using auto supports is not a good idea. In the image below you can see a test print I ran. On the left is the model supported with manual supports. On the right, well only the supports survived. Now I have to go clean my vat.

After you have identified and supported all the islands you should be ready to slice your print.

Use The Best Settings in Your Slicer

Remember step one where we ran a resin calibration print? Now is the time when that information becomes handy. Your model is now supported and ready to print. Let’s talk about the slicer settings in ChituBox. Open the settings menu by clicking the Settings button on the right-hand side of the screen. If you are in the supports tab click the tab to the left with the Gear icon.

The first tab in the settings menu should have been set automatically when you installed Chitubox. We can leave these settings as they are.

The resin settings tab is useful if you want ChituBox to calculate how much your print will cost. Change the price you paid for the current resin in your resin vat to get an estimate of print cost. The calculation will only show up if you have the feature turned on. If you disable volume calculation, it will speed up the slicing time, but you won’t get an estimated resin usage and cost.

The print settings tab is where you will enter your exposure time that you found with the exposure test. It also contains several other settings of note.

Layer height will have a direct impact on quality. Lowering the layer height can increase detail but it will increase the overall print time. I recommend making a test print of the same model at both 0.05 and 0.025mm then compare the outcome. If you are happy with the details from the .05 stick with it. If you like the detail on the .025 model and don’t mind the longer print times, go with .025.

Bottom layer count and bottom exposure time are settings that help your print stick to the build plate. Bottom exposure time should be around 10-12 times your layer exposure time. If you have issues with build plate adhesion, check out my article here.

Exposure time is how long the light turns on and exposes non bottom layers. This is where you want to enter the value you got form the resin calibration test. Be sure this is set correctly as it will affect your print quality!

Bottom lift and lifting distance tells the printer how far to raise the build plate between layers. 5mm works well for most machines and you shouldn’t need to adjust this setting.

Bottom lift and lifting speed determine how fast the build plate raises between layers. Decreasing lift speed will allow the print to peel from the FEP more slowly. Slowing down your lifting speed can reduce the risk of failed prints or the model breaking free from supports. The downside is that decreasing lift speed will increase your overall print time. I set my lift speeds to 60mm/min and find it works well for my Elegoo Mars.

Retract Speed tells the printer how fast to lower the build plate back down into the resin vat. The default is 150mm/min and should be left at that value.

Once you have entered the correct numbers into the settings box they will be saved, and you can click the X to close the menu. Your slicer is now configured and ready to go. After you have your model supported and the settings entered click Slice and wait for ChituBox to generate the G-Code for your printer. Once it’s done click save and save it to your computer. After it’s done saving you can click open folder to see your saved file. Copy this file to the USB drive you use with your printer.

Print the Miniature

Here we are. It’s finally time to print your miniature! I will assume you know how to use your specific printer and that the resin vat is installed and filled with resin. For this article I used Elegoo Standard Grey resin (Amazon link). Load up the print file from the USB drive and click print! And then wait nervously to see if it works. A telltale sign that things are going well is a slight popping noise as the build plate lifts between layers. This noise is the resin releasing from the FEP film and indicates that the model is sticking to the build plate.

It will be forty minutes to an hour before the build plate is high enough out of the resin for a sneak peek. The printer will tell you how long the print will take so you can set a timer and come back when it’s done. I recommend checking on the printer after about an hour to make sure the print looks like it’s sticking to the bed. If your build plate doesn’t have anything attached as it pulls out of the resin vat, it’s time to cancel the print and clean your vat.

Remove the Print from the Build Plate and Wash

Ok, now the printer is done! Your beautiful print is hanging suspended from the build platform and you can’t wait to see what it looks like. But have patience, there is still a lot of uncured resin clinging to the model. If your printer came with an adapter to tilt the build plate inside the printer, now is the time to use it. Let the build plate hang and drip for about 30 minutes to get as much resin back into the vat as possible.

Now the plate has been dripping resin for 30 minutes we can take it out of the machine and get a good look. At this point it’s not going to look great as there is still residual resin clinging to your print and obscuring details. We need to wash off the extra resin before we can do the final cure. Remove the miniature from the build plate and put it into your washing container. I highly recommend getting a wash and cure machine as it makes life so much easier. I recommend the Mercury X Wash and Cure (Amazon link).

Don’t rush this step as any residual resin left on the print will ruin the details in your print. Experiment with washing times to find what works best for the resin you are using.

After the minis have been washed in your cleaning solution let’s remove the supports. Removing supports pre-cure will reduce damage caused by the supports. Rinse your prints in warm water, the warmer the better, and gently press and pull on the supports. They should pop right off leaving minimal scarring on the model surface. Use flush cutters to remove and stubborn supports.

Let the Miniature Dry and then Cure

This is probably the easiest step. After the print had been washed and the supports removed let it air dry. Curing the print before it is dry can result in residue on the print. Put the print into your curing chamber and wait for it to finish. Once it’s done remove it and marvel at the details and quality that resin allows!

Sand and Fill

Hopefully, with proper model orientation and support settings you will have minimal damage to the print. If you do have some damage, or maybe you missed a piece of support material, you’ll need to do a little work. Get some fine grit sandpaper or sanding stick and use them to remove any leftover support material. Wear a dust mask as the resin turns into a fine powder when sanding and you don’t want to breath it!

If you have any pits or divots in your print from support removal fill it in with some green stuff or Tamiya modeling putty (Amazon links). After it dries sand it down flush with the surface. Don’t worry about color difference as you won’t notice it once the model is painted.

Prime the Print

Now we can prime our miniature for painting. It is extremely important NOT to use a spray can primer made for plastics! These primers will react with the resin and you will end up with a stick print. Use an acrylic based primer to prime your resin miniatures!

Paint your Print!

Well here we are, time for the fun part! You’ve printed, post-processed and primed your model. Now it’s ready for you to make it look table ready with a great paint job! If all has gone well your painted 3D printed mini should be mostly indistinguishable from a store bought mini. You are no longer restricted by what plastic models are available in stores. There are artists making hundreds of printable miniatures each month. Enjoy your new hobby of 3D printing miniatures!

Sadly, I haven’t had the chance to paint my dwarf model yet. So here is a chef model that I used in my previous article on support removal. I threw a quick and dirty paint job on the model as I needed it for a D&D game with the family. Shoddy paint job aside, unless you look at the model with a magnifying glass you can’t tell that it was 3D printed.

For comparison here is the cook next to a zombie ogre miniature I printed on my FDM printer. You can clearly see the layer lines up close.

Hopefully, you have gained some knowledge from this guide on printing 3D miniatures. If you are interested in getting a 3D resin printer be sure to check out my recommended resin printers page here. For more guides and information check out the other sections on the website!