hello everyone my name is alex i'm a lab technician from the digital manufacturing lab welcome to this short lecture as a following part of your chat chess piece design project i would like to show you the pipeline of attitude manufacturing process which basically what happened after you submit your homework so let's get started with the design definitely you need a digital representation of of your design to get started with 3d printing so there are really two ways to get that first is use cad software now is use 3d scanning technology the 3d printing process don't care about what kind of software you use to generate that digital model as long as it can export some file that is readable by 3d printers so as i think you probably already pretty familiar with the cad model cad software i think most of you choose to use that let's talk a little bit more about the 3d scanning process we do have a high fit definition 3d scanner available in the digital manufacturing lab it used infrared technology to scan the part most of the part is most of the this technology used to do the reverse engineering or used to recover a broken part it works better for the matte part which don't have a shiny surface and also with a convex type of geometry for those like uh the chest piece shown on top right it has some very small details internal structure and it also has many holes which thoroughly unable to be captured by the 3d scanning process so it looks a pretty convenient technology to generate some digital model pretty easily but there are some limitations so once you finish your design you need to export the the file as a stl file which is the most all most common format for 3d printing so what what is a stl file actually it comes from standard triangle language which obviously kind of show what exactly it is basically it's combat it is a collection of all these small triangles they connected together to form a geometry surface which is actually just the shell it's uh empty nothing inside the shell but just to replace to represent the surface of the geometry so there's no color no material no other information other than the surface geometry there are two formats of this kind of stl file one is in text format which is easy to read by human another is more compact in binary format which saves some storage space on your computer so they are actually identical actually but they just use for different purpose so there are two things we need to care about before start 3d printing one is the model integrity which we need to make sure the stl file is correct there's no error the shell is closed uh and it is a water tight geometry another thing is the unit because there's only numbers in the stl file there's no additional information you can identify what is the unit is actually so if you want to find more information about stl file you definitely can go to uh wikipedia or some website there are plenty of this information available online uh when i talk about the integrity we usually don't do that by checking integrity by human being because there are usually many small details in this stl file we use some software like netfab or mass mixer or some online service that can help you check the model quality so if there are some gap some error in the small triangles there really another good indication you can use is the volume if there is some error in stl file the volume usually not able to be calculated correctly so if you find out there is some that there's no volume information of your part can be calculated they already mean something wrong with the stl file so after checking the integrity we also need to make sure the unit correct this can be done by uh read the boundary box size with basically the length the wise and the height of the part this also gives you a basic idea how you're going to position that in your 3d printer to make sure that it's not over the capacity of the 3d printer and that definitely will help to avoid any failure because of the part is too large or too small so next thing uh the technology we use to print all these chest pieces is called fdm uh fused deposition modeling technology basically it extrude the the melted plastic from a heated print printhead like the one shown on the on the image once the filament is dried into the printhead it will be melted and extruded on the final part this process also uh this printhead also mounted on a gantry system while it is extruding the material it can also move around this whole process is done layer by layer from bottom to the top after that the whole part will be building slowly from bottom to top in the this kind of layer by layer process so to convert the stl file to a machine readable instruction gcode url gcode but it can also be some other type of code uh we need to use a slicing software as you can see the this process this 3d printing process is done by layer by li is done in a layer by layer manner so just the software also need to do that to calculate how the printhead is going to move so the software we use here is the grab cat print once you import model do some optimization of the orientation and position basically how you're going to place that in your 3d printer and then you need to generate the support structure which will which is definitely necessary because all these deposition process need to be done on something you are not able to print directly in the air obviously so we have to generate this type of a support structure in this software after we do the calculation the software will show us the model which is your as from your stl file it also gives you how the support material support structure is going to look like this software this model is showing in green and the support material will show in this kind of yellow color so talking about the support material it definitely required for those that has overhand or have some internal details like the one shown here uh actually when we do the 3d printing we can sometimes by separate the part into two pieces or change the orientation sometimes we can avoid this this temporary support structure this structure definitely need to be removed after we print this part because they are they are additional they are not what we design and not what we want so to avoid the support structure by changing the orientation or some other settings that can help us save some time and save us some material so specifically for those uh chest piece we use module and uprint for this printing we have advantage feature is the use water soluble support material once we finish the printing we can easily remove the support structure without some trimming or cutting things required so it's kind venice and it is a pretty advanced technology rather than those low-cost 3d printers so this short video shows how this uh chest piece is being printed in uprint you can see the printhead is moving around and it also deposits some material on this print bed so this process looks slow but actually it takes usually several hours to finish the to finish the whole part after that we need to do the so-called post-processing which basically remove the support structure as a picture on the left shoes apart just right just after finished printing it has support material in a white color and it the model actually uh kind of ivory color after the post process we will get a clean clear model uh the post process is down in the in a hot bath which we add some water and some support remote removal agent with the help of this kind of chemical the support material will be easier to be removed this process also takes several hours sometimes we just leave the party in the bath for overnight so we'll after that we will get a pretty clean and smooth surface of what we have printed so something like the part shown here so basically that is all these steps uh we work through and a little bit more about the digital manufacturing lab we are operating under the umbrella of a ub science and engineering shared facilities we offer some 3d printing cd scanning and other services so most of these services are free for students but we do need to to charge some money for 3d printing basically recover the cost and avoid these services being able to use so if you want to know more details about all these things please go to our website we have our wrist posted and some instructions introduction about 3d printing stair that's all about it thank you and stay well