Shredder jams…

Hi. I have built a shredder from Precious Plastics blueprints. Power by a 1.5kw 70 rpm motor and has a mesh underneath. I used it for the first time today and experienced some jamming when just trying to shred an HDPE milk bottle. no reverse on the motor so had to dismantle! can anyone suggest why its jamming and possible fixes? Is there a better configuration of the cutting teeth or using it without the mesh that will help? Thanks……

I don’t have a PP shredder but could you grab the coupling with a strap wrench to drive it backwards to un-jam? Or if you have it apart, machine some flats on the end of the hexbar to be able to get a wrench on it?

This is commom problem with PP shredder, the torque output on a typlcal gear box that you may have is around 150Nm-200Nm which isnt enough. You will notice if  you shred thin items upright it will shred beautifully but if it lies flat, the shredding surface area increased and not enough torque to break the plastic along all the teeeth that need to shred. Either you can have a auto-reverse built in. Our compnay build shredders that auto-reverse. Another approach we took is to put the same motor but by an in-line gearbox, these output torque around 300-450Nm

get just a stronger motor; looking at the cables and capacitors, there is no electrician who can fix this.

Ah ok. Well that’s a bit worrying. I will check it out with the electrician and see what can be done….thanks for the feedback.

Hi, judging by the capacitors size it seems really under-powered. Here again a few links about motors.

Hi Pex12,

Sorry it’s been a while but been out of the workshop. I have added photos as suggested and also noted an electrical fault, which is being looked at tomorrow, but any advice you can give on the teeth set up and general ways to avoid jamming plastic int he space I would really appreciate it!! Thanks. Rick

please post a picture of the motor blade, also open the wire box to see the terminals. thanks.