Shredder 2x

We are at around 2 weeks now of full time 8 hours a day use with the double sized shredder.


Powered by a 5hp copper wound motor, and using the following speed reduction:


motor 1750 rpm with 3 inch pulley.

connect to center axle with a 12 inch pulley.  giving us a 1:4 ratio. 437.5rpm

this in turn connects to a 15 tooth type 50 chain sprocket, and the shredder has a 58 tooth sprocket. giving us (check my math here) 112 rpm?


Nevertheless, it has been running daily shifts with packaging foam scraps.

After 2 weeks, no visible blade wear, even the slag coating on the hot rolled steel is still intact.  No tooth deformation.


The users are feeding the machine with foam and jamming as much as they can down the chute, while using a rolled cardboard tube as a push stick.  It resembles a juicer in operation.


after a hour to 90 min of heavy use however they have to take a break as the blades will heat up from the friction.  The shredder body itself will be too hot to touch by bare hands, although with the large metal frame, the heat quickly dissipates off after a 15 min break.



center axle will move in its pillow block bearing.  I need to put a small stopper on the axle to keep it from moving.  Set screws are not enough.

Initially I was told that the grade8 bolts with lock washers was overkill.  However upon heavy use, I found that a couple bolts without the lock washers had come loose.  Basically every single bolt in these machines needs a lock washer or lock nut and preferable to use high grade bolts.  You just can not cheap this part out.


The 3mm galvanized steel sheet metal frame is holding up well.  No deforming while under heavy load.  However the caster wheels we used are not really heavy duty enough.  they do work but are slightly deforming.  We need a better quality wheel for future builds.  Possible to maybe use 2 large gate bearings (very cheap) for the back wheels and swivel casters for the front?  The large casters prices goes up exponentially the bigger the wheel I buy.


The addition of a 63 amp double pole transfer switch to add in a forward and reverse to the machine for jams has been a huge improvement.






some video of it in operation  Redirecting...

hey @btmetz
that are strong and good additions; I love the feedback. Eventually you could add a few more links, images of the components you’ve been using ? Other than that, I will migrate your variant in the pp library; great stuff. I guess i pick the content from FB and here for now. About the sprocket math; there is always good stuff in the machinery handbook (just buy it) but a good exercise to do …