Steven Mosbrucker

https://youtu.be/LJ9OspwEA5A
Above is the video i made about shear stress hopefully that helps.

I replied inside my original post that you read the calculations required for shredder. I will make a video to explain but the blade thickness has nothing to do with the calculations. Check out my reply ask me any questions you have.

Hey guys I have been in and out of the forum. I am going to try to be around more often as I am trying to move into this space and away from my day job hopefully soon. So in shear mode of failure the thickness of blades makes no difference in the determination of the cut area. The thickness of the blades determines if the blades will survive the…[Read more]

Badass project guys.

So basicly these cross section are regardless of blade thickness. The cross section is with respect to the parrallel contact of the blade the cross section goes top to bottom not along material. Where blade thickness comes into play is the resistance to torsion at the hex/square shaft input.
My perticualr and precious plastics design has only 1…[Read more]

This is the correct link.
As long as you get it small enough it is not that much different. I will probubly have a different hopper as shavings dont really roll as well into barrel compared to the virgin resins. as the current hopper design is for pellets.

I am also still working on opening up my first version of the extruder (Multistruder) as open source the idea is that it is supposed to be a injection machine and a high quality filament extruder all in one machine. I am adding the feedback loop for diameter control and the option to work as an injection moulder currently. But that one you should…[Read more]

https://studio.youtube.com/video/-4ELb3uyVSI/edit

This is the current one that i am working on. I need to add production grade screw however i lost access to my 4th axis add on to make a custom screw for it so i am going to use modified wood auger for now. Currently i have the winder and spooler working. I am now working on getting my working…[Read more]

thanks. Yea i have been away for a while because of universtiy. But i actually just graduated yesterday for mechanical engineering so i do plan on being on here more often and spedingmore time on stuff such as this and The Green Engineers.

so that goes to about .25″ x .25″. thats not that bad. most of everything that is shredded is waterbottles…[Read more]

3 point bend test is best for plastics usually. Another one that would be huge for Precious Plastics and myself is a shear test. Look at how much force it takes to shear the plastic. We can use that in our calculations for shredder for force needed in shredder. also torsion test would also be nice. and mabye even iziod inpact test. but with that…[Read more]

I have a project that i want to use sheetpress for. It is for pressing completely clear PLA pellets into .125″ sheets have you tried the plant based plastic PLA. i know it isn’t recycling but still.

The easiest for solar direct sun beam heating i think is the extruder. Direct the beam at the barrel. Now using a PID controleryou have 2 options of control of temeprature
1. Use the PID controller that when off something such as a piece of aluminum or something falls infront of the beam thus blocking the beam from the barrel. when on that peiece…[Read more]

So what S2019 is also what i am doing on my second version of my filament maker dubed FilaFactory. in this video i show the testbench. it is a little beat up but you can see that i have 2 40 watt heaters with holes drilled and them put inside the holes. Also be sure to have a hole for a thermisistor or thermocouple. Also you need 2 small holes…[Read more]

I have a design for my second version of my filament maker dubed the FilaFactory. The test bench of the machine can be found here.
https://www.youtube.com/watch?v=-4ELb3uyVSI

Yes the screw does increase the pressure. The general guideline is 3 to 1 compression. so at the end of the scree the volume per flute of screw would decrease by 3 times.…[Read more]

well another place says 55Mpa usually rule of thumb is 60% of the ultimate stress. Ultimate stress is used as yield stress is not the stress required to actually break the molecules inside the bond to break them. Yield stress is just what is required to reform the structure/shape of the material. Ultimate stress is the stress required to break the…[Read more]

Well. You are using the wrong stress. That stress is fail in compression or tension. You want to cut the material this is called shear. so you want to use shear stress which from the first site i found is this Shear Strength, Average value: 15.3 MPA. so this is about 6 times lower than the value you are using.

if it is an exturder i think my first one i used 24 watts. at 1 inch diameter .5″ radius and 19 rpm. so like 16 Newtons or like 3.6 lbs.

Me personally i would not use the calculation of power as a calculation end. I would look at force. 5.46 tonnes is plenty of Weight aka Force to shredd plasic. you can shredd plastic with a 1/4 inch blade with like 180lb depending on the moment arm you use to turn shredder (3 feet). This all depends if you are talking about powering a shredder or…[Read more]

i built a online calculator to do so check it out.
http://www.thegreenengineers.com/ShredderCalculator/index.html