Hard Shell Basic Mask

thingiverse

<b><u>Update</u></b> <b>31/03/2020</b> (2) I have uploaded several new images of the latest design. Printing the bottom section with threads in TPU is not recommended, as the threads will tend to bind more readily than PLA to PLA. It may work fine if the entire section can be printed in TPU, but if it's just the end, the TPU and PLA may separate under pressure when threading in the filter. The TPU gasket is loose at the threads, so this doesn't have the same issue. My silicone sealant gluing appears to be working okay so far. I tried using a cyanoacrylate-based glue that works but is rigid. After the materials flex for some time, the bond weakens. I'm hoping the flexible silicone sealant won't have this problem. <b>31/03/2020</b> I added a new version of the PLA/TPU combo mask (V3). The new design fits me and my wife pretty well. It does need to be shifted on the face to allow it to fit properly. I may have to try and redesign the top edge so it is a little thicker and move the strap holes a little so I can get more TPU at the edge. <b>28/03/2020</b> (2) For anyone who wants a slightly larger tool so it's easier to turn, I just uploaded a Filter Tool Tall. <b>28/03/2020</b> (1) I updated a new full mask seal that is not as large as the previous one posted. The new seal needs to be printed in TPU and will add a softer surface where the mask touches the face. An alternative to printing a TPU seal is to take a length of small diameter silicone tubing, cut a slit lengthwise, and place it around the mask edge. <b>27/03/2020</b> (2) I just realized I forgot to upload the filter gasket. It's now in the file list. <b>27/03/2020</b> (1) I uploaded an upper seal that can be printed with TPU. The mask can be moulded slightly by heating the shell with hot water or hot air and bending the edges carefully. The TPU seal can be used to fill some of the extra gap for those with smaller noses and lower bridges than mine. <b><u>Summary</u></b> Here is my latest hard shell mask design. This is designed to be printed without any supports using PLA or other similar filaments. I did not have any success printing it with TPU, but I have only just started playing with flexible filaments so it may just be me. There are 3 parts to the mask that can be printed in PLA: the main shell body, the filter cartridge, and the cartridge cap. There is also a cartridge tool that you can print that makes assembling the cartridge a little easier. Note: The nose pad and copper filter are not included in the parts; they're only for visual demonstration purposes. I just used some of my wife's make-up remover pads as the filter material. The filter material gets inserted into the cartridge, and the cartridge cap is screwed in to hold it in place. The whole cartridge assembly is then screwed into the front of the mask. Use TPU filament or other material as the straps to hold it on. The shell is only 1.2 mm thick so it can be softened and reformed a little if necessary. It fits my face, but the nose bridge is quite high so it may need some foam or other padding around the upper edges. There are different types of materials such as self-adhesive weather stripping or soft, flexible medical tape that could be used depending on the thickness needed. I am looking at ways to print a TPU upper seal and will update it if I come up with a simple solution. Note: This is a dust mask and is not meant as a medical equipment replacement. If you succeed in printing it in TPU, please let me know.