Low Polygon 3D models or Low Poly in short are a popular trend lately when it comes to 3D printing as they do seem to be easier on the building process for the physical model and the end result is really nice most of the time. So Looking for Low Poly model on websites such as Thingiverse for example can produce hundreds of results with nice looking low polygon count 3D models ready for free download and printing. What if you want to make a Low Poly version of a detailed mesh of a 3D model you already have, but you may not be very good or at all with 3D modeling software to produce it? Well, I figured that I can tell you how to easily do it without the need of extensive knowledge or having to deal with too complex software…

Choosing a Detailed 3D Model with a Lot of Polygons
Do note that not all 3D models will look nice if you reduce their number of polygons in order to make them into a Low Poly version of the original model, some will just not be Ok, others might end up surprisingly good, so do try and experiment. I have chosen a 3D model of a Lion Head to work with in this guide to illustrate the process. It might not be the best one for Low Poly version, though it does work pretty well for the purposes I need it… again try and experiment with different models to see what works better and what not.

What you need to look for is a 3D model that is already pretty detailed and comes with a lot of polygons, so that you can reduce them significantly. 3D models with not that many polygons building them up that already may look a bit blocky are usually not a good source of material. I have already covered an easy tutorial on how to make lower polygon count 3D models using Blender look smoother, so you might want to take a look at that earlier post.

How to Easily Make a Low Poly Version
The software that I will be using for this is called Autodesk Meshmixer, it is a free application that actually has some pretty nice features available for working with 3D models that will be later on 3D printed. So it is a nice tool to have in your arsenal if you are an owner of a 3D Printer and are using it to print various 3D models, already made by somebody else or designed by you. So even if not for the easy Low Polygon 3D model making you might want to check the other useful features available in that software…

You need to start by Importing the 3D model of the object that you want to create a Low Poly version of, just use the Import button and select the file you are going to be working with. The software supports OBJ, PLY, STL, AMF and MIX file formats and the most likely one you are going to be using here is the STL as it is the most common one when talking about 3D printers. You can of course also start with an OBJ file for a 3D model of something that was not originally made for 3D printing, but for some other use or any of the other supported file formats.

The Lion Head 3D model I’m using for this example is in STL file format as it was originally designed for 3D printing already. The 3D model of the head uses 183898 triangles (polygons), so it is not a very simple model and you can see that by zooming in and checking the many details that it originally has… details that would most likely be lost when 3D printed due to the lower resolution that 3D printers normally use. Fortunately the goal here is to significantly reduce the large number of polygons and get a Low Poly version of the model ready for 3D printing.

The next step is to select the complete 3D model, to do that just press the CTRL + A key combination and you will see that the gray rendering of the model becomes a kind of orange. This means that anything you do as an operation from now on is going to be applied on the whole surface of the model, this is exactly what is needed when reducing the number of polygons. You can of course also make partial selection and work with it instead of the complete surface of the model, but for the current goal that is not needed.

From the Select menu you need to go to Edit and then choose Reduce, alternatively you can just press the Shift + R key combination to get to the same menu. This is where the fun part starts as you need to do some experimenting in order to figure out what is the best looking result…

In the Reduce panel change from Percentage to Triangle Budget as this just makes it easier to work with and get the desired Low Poly result as you may go to below 1% on some higher polygon count 3D models. Then just click on the value on the right of Tri Count and type a new value as a number of Polygons and hit Enter to see the preview. To apply the desired value after previewing it you need to click on the Accept button, prior to that you can experiment with different values.

Normally getting a good Low Poly version of a 3D model means that you need to go for something in between 1000 and 3000 triangles in the Reduce menu, though it also depends on the 3D model as well. You might need to go lower or higher than 1000-3000, but this range should generally be where you would need to try first. In the example Lion Head 3D model 1000 polygons are simply not enough to provide a good looking Low Poly result, so I need to go higher. At 2000 polygons things are looking better, but going a bit higher than that at about 2500 makes it even better… you can also go to 3000, but going much higher than that is not going to provide the nice low polygon look that I’m looking for.

When you are ready with the Low Poly version you will need to save the new 3D model, make sure you don’t overwrite the original high polygon count version. Just go to File and Export and type a new filename, make sure you save as STL file format, so that you would be able to easily open it up in your 3D printing software. Then just open it up and 3D print it from your slicer…

The image above shows a side by side comparison of the original high polygon count model (on the left) and the Low Poly version that I made using the Meshmixer software (on the right). The low polygon count model is with just 3000 triangles as opposed to the original that uses more than 180 thousand polygons.

This is the preview of the two models as the way they will look when 3D printed using 0.01mm layer height (high level of detail), as you can see and as I have mentioned already there is some loss of detail in the high poly count model due to the lower resolution that the 3D printer uses (even when printing in high quality)…

I finally got my USB microscope that I have ordered last week and have posted about and was eager to try it out and see the level of quality it provides, so I took up some small 3D printed parts made with different type of filaments and I looked at them up close, really close. I’ll be covering the USB microscope in a separate post, so here I’m just going to be posting a couple of photos taken with it to show what it is capable of.

The 3D printed parts in the form of small Monopoly type of houses are all made with PLA-based composite filaments using 0.2mm layer height and the crystal type model is printed with 0.1mm layer height using UV curable polymer resin. I’m mentioning the layer height as it can help you get an idea on the level of zoom that you get as the separate layers building the objects are clearly visible with the help of the USB microscope. The quality is quite good, though there is room for more to be desired. The photos below have been downsized to 50% of their original resolution in order to be smaller and easier to load, the original resolution is 5 Megapixel.

PLA filament infused with very fine wood particles to make the resulting 3D prints lighter and feeling more like they are actually made from wood. Using different extrusion temperature with this interesting filament allows you to even vary the tonality of the printed “wood”.

PLA filament infused with finely chopped carbon fibers to allow the 3D printer to print with carbon like filament that is stronger and lighter, though not as strong as with real woven carbon fiber.

Flexible silicone-like 3D printer filament called NinjaFlex that allows you to get some really interesting 3D printed objects that can be bended and stretched without breaking.

Sandstone-like result from a special type of 3D printer filament that infuses PLA plastics with fine chalk powder to give a really nice looking result. With this one the different layers are actually much harder to be noticed than with other filaments.

Special type of polymer that is in liquid form and then is cured with a laser or an UV light source in order to become solid and strong. This process allows for higher levels of detail, but is not suitable for larger objects as it takes more time for things to print and is more expensive due to the polymer used.

I guess that I should be able to inspect 3D prints at a really good detail level using the USB microscope from now on, though probably relying on some natural light may help get better results than having to rely on artificial light for taking photos of the 3D printed parts. Could be especially useful for times when I’m trying out new and more exotic composite material types… I do have some with metal particles ready and waiting for some testing.

Computer games that simulate realistic car driving experience have come a long way and so do the peripheral devices used to control the cars in the virtual world. Racing wheels for your computer game simulation do play a very important role for a good experience and the ultimate realism is achieved when you actually mount the same racing wheel on your simulator as the one that you use in your actual car. This is still not happening from the store as it would further drive the price up for the computer peripheral and good racing wheels already are pretty expensive when you are buying them to build a computer-based simulator at home. Fortunately there are alternative options available as I have discovered when a friend asked me to 3D print him a mounting adapter for a real car racing wheel that would allow him to attach it to the Thrustmaster computer racing wheel he is using. He didn’t even have to design the 3D model by himself (or ask me to do it for him) as it was already available on Thingiverse from another user, so that makes things much easier.

Getting Ready to 3D Print
The 3D model of the wheel adapter is not very complex as far as 3D printing goes, there are no hard parts that would require you to use support materials or do some extensive postprocessing work. It is probably best to use ABS filament for printing this adapter as it will provide a stronger part, but there are some additional requirements such as a heated build plate for the 3D printer and ABS is generally harder to work with. For the specific requirements a PLA print with higher infill percentage should be more than enough in terms of strength as well. Since there are no high temperatures in the usage scenario there should be no issues with using PLA filament whatsoever, though I have used a PLA/PHA mix as it offers a bit more tougher and less brittle build than when using regular PLA.

The printing parameters I have used are 0.2mm layer height, usually referred as Medium, because we don’t actually need that much detail and for the required precision this level of quality is more than enough. The infill percentage I have settled for is 40%, no need to go all the way to 100% to have a fully solid object, as even at 40% the inside grid should provide enough strength and durability without needing that much material as a fully solid object would require. With these settings the slicer said it would need a bit more than 3 hours to finish the 3D print of the wheel adapter, however it took more like 4 actually from the start to the finish.

Some Photos from the 3D Printing Process

Photos of the Finished 3D Printed Wheel Adapter

Mounting the Wheel Adapter to the Wheel
The mounting of the wheel adapter to the real racing wheel is done with 6 screws and 6 nuts, the nuts are being locked in place inside the adapter, so all you need to do is to fit them in and tighten the screws. The 3D model of the adapter should provide a very tight and accurate fit for the screw and the nuts, though that may depend a bit on the material used and the 3D printer you have. In my case it was a perfect fit, but with ABS filament shrinking a bit it could be a bit more challenging to assemble things.

The Final Step Left to Do…

The only thing left to do now is to mount the new racing wheel on the place that the original Thrustmaster is and give it a try with the adapter. The drawback for this relatively easy conversion is that there are no easily accessible buttons on the new wheel, though there is a DIY solution for that as well. Some people are hacking the Thrustmaster interface with the help of Arduino boards and are adding extra buttons to the real racing wheel, so it gets even better for the simulator. I’m not doing that for the moment, but if my friend asks me for that I can actually do it for him as well as working with Arduino boards is really easy and fun thing to do… and if I do that I will probably also have a short post about it.