I have a project that I am currently working on and in order for it to work I need to be able to get weaves of different densities radiating outward as the image suggests (thick density in the middle with less flex outward to less density and more flex). It has to all be on the same plane though. Anyone know where I can learn more and see some examples of products or process?
I relaize that im probably asking the wrong question so I will rephrase. Using a single material, are there any mesh patterns that are more structural than others? Is there a reference that I can look at? I am basically putting together a mesh that needs to be flexible in some areas and stiff in others. Any advice would truly be appreciated.
The pattern in the image you have there has a smaller pore size in certain areas than others and that is basically what I am looking to do on a flat plane. The application is medical and unfortunately I can talk much about it. I can definitely answer your question though.
You are trying to control the deflection of the mesh – how is the mesh being loaded? – There will be no load on the mesh, the center area has to be stiff to stop it from flexing in the Y axis
If the mesh is only as strong as the weakest member, does it matter that the stiff sections will deflect as much as the less stiff sections?–I believe the answer is No, but could you explain what defelction is? I am assuming its the dispersion of the load?
What materials are you hoping to use?–Polypropylene or any medical grade mesh that is similar
Check out circular knitting machines. Seamless knitting for socks etc. You have to do some experimentation but the possibilities are endless. I did some work with seamless liners for snow helmets, the way the produce the different areas of densities and directions is with a bitmap image that gets fed into the software, very quick feedback.
This video shows the machines.
Issey Miyake A-POC method for more computerized knitting solutions.
Wow thankyou so much nxakt! This is some great stuff. I love it! My appologies for such a late reply as I was travelling and then fell under the weather. I appreciate all the help. Keep them coming if anyone else has some cool stuff!
Most filters are made from nonwoven materials. Unfortunately, needle punching is done at a scale that it is uniform. But there is no reason why you couldn’t layer different nonwovens to get the non-uniform strength you require.
Have you thought about injection-molded rubbers? Have a look at the Mobilegs crutches. The saddle uses an extremely flexible weave for the saddle. The pattern has voids that vary in size and density. The material was originally developed to couple train cars together, so it is extremely strong. I’ve included an image from the web but if you can examine one up close and personal, I think it would be very beneficial.
The material has to be medical grade and live inside the human body, I was thinking polypropylene mesh. Is there any material you can die-cut that does the same thing? I think that would be an awesome process because you would have complete control on the mesh properties
Plenty of films are bio compatible. PE, PP, PU, pretty much everything. You will need a converter. I have used Plitek and place out in CA but the name escapes me. There is a long list of converters listed on MDDI.
Of course your biggest worry with an implantable is the creation of a biofilm on your device. You can get films with a silver and other antimicrobial coatings but I have yet to see any in vivo evidence that they work. There are films that will dissolve over time, lowering your biofilm risk.