My Shredder

It’s been a while since I started my Shredder project but didn’t have the time to actually finish it, but I can now say that my shredder is 99% complete (I say 99% because I have not attached the power cable yet, but I already have it)

Here are a few tips:

*Don’t use a motor that is less than 2hp. I purchased a 1/2HP motor and it does shred plastic, but the threaded part of the bottles makes the motor halt. A 2HP or more motor should not have this problem, and if possible, get a triphase one.
*I did not want to buy a perforated sheet of metal because I only needed a small square piece and the hardware store would not sell the amount I needed, so I grabbed a perforated metal sheet I found in an old speaker and it worked just fine (see pictures below)
*On my Shredder’s frame I soldered 4 small pieces of square tube that I can use to put a piece of wood, that will serve as a base for a trash can that will collect all the shredder plastic
*Get a DPDT rocker switch, that will allow you to reverse your shredder motor if the shredder gets jammed

Here are a few pictures:


Hello @xxxoliverxxx,

I have a motor with similar specifications to the one you used in your build however on the gear reducer tag it says max output hp is .75 and the torque is around 560 lbs/in with an rpm of 68. I am curious if this sets my motor apart from yours? Unfortunately I have already purchased it and am hoping I didn’t waste money on something that won’t work. Any input you can offer is appreciated!


thanks for your drawing…will try it…

regards Ken

look for me on google ,35 allambie Rd Orielton tas 7172
Little Devil Antennas Orielton TAS 7172

hi, do u have the wireing details for the single phase motor. re, reversing switch diagram.

regards Ken

@nonanoplastic With more blades and more plastic, you will need alot of power from your Motor. If you have that, then go for it, but as you see on the video that @xxxolivierxxx shared, then it has a hard time just shredding one bottle-button. I would advise to just go for the set 14 blades, and make it work with a motor that fits.
That would be most efficent and low cost, as i see it 🙂

– Mathias

Hi Guys, I have a burning question in mind.

What if I add extra blades and make the shredder longer, will it give higher capacity/output of the plastic that will get shredded?
and want about the engine? can the same capacity work well if we add more blades?

Does anyone have ever try it before?

I would really appreciate it if someone can reply to me about it.
thank you very much in advance.

Cheers, Nila from Nijmegen.

@dazawashere sorry, hasta ahorita veo su mensaje 😛

Que mae!? ^
Viejo, en Infesa (Cartago, Curridabat, entre otros) tienen motores de segunda con un mes de garantía, y ahorita están en liquidación.

Pegue una ojeada en el site:

Yo ahorita estoy comenzando el proyecto junto a un compa, por ahora tenermos listo las partes cortadas y estamos buscando ya las demas partes.

Donde fue que conseguiste el reductor? No he averiguado si ahí mismo en Infesa tendrán.

Mae por cierto, que tuanis le quedó la maquinilla!

Pura vida loco!

Hello @pereka

The motor you posted looks pretty good, but I encourage you to get a pre-assembled combo of Motor + Reductor to ensure that the reducer you get fits your motor, or at least try to buy both parts from the same seller/place to test that they fit together.

The reducer you need depends on the motor RPMs, the resulting RPMs of the reducer should be around 60 or 70, anything faster might actually melt the plastic due to friction, instead of shredding it.

Most reducers rotate in both directions, in case you find one that doesn’t, I’ll recommend to look for a reducer that does, since having backward/forward rotation is a must-have feature in case you ever need to unclog/unstuck your shredder.

Yes, a coupling is necessary. What type of coupler? Anyone that fits your reducer’s and shredder’s shaft: Universal, Oldham, Jaw, etc…

Hi Oliver i think your shredder is swell and thank you so much for sharing the information with all of us . There’s a lot to learn and i’ve been going in the forum to find the proper info on a suitable motor , motor reducer and VFD before i proceed .

Motor spec: (we have confirmed to go with this)
Link: (
> 3HP/2.2kW
> 3Phase
> 230V
> 50hz
> 2 pole
> need to be delta connection (for VFD)

Motor reducer spec:(unsure whether what other info i need for this)
> compatible to the above motor ?
> to run on 70 rpm
> able to change direction ?
> Nm ?

VFD spec:(3Phase to 1Phase connection)
Link: (
> 230V , 2.2kW

Coupling ?
Is this necessary i am unsure of this too . VFD is required to change from an industrial socket to a home plug wall socket compatible.

Would love to hear your reply and knowledge @xxxolivierxxx @davehakkens

Thank you again I totally appreciate it !

Regards ,

Hello everyone
I live in Ivory Coast and I am interested in the construction of machines. I would like to have the parts for the shredder crusher and the electrical equipment of the other machines.
If you have ideas or proposals (cost, transport …) to give me please contact me at the following address:
Thank you in advance for your help.

your build looks great! thanks for so much imagery and guidance.

quick question, do you reckon we could get away with using smaller wall thicknesses for the frame? the BOM says 30x30x3mm, but do you reckon 30x30x1.6mm would be sufficient?


Nice Job on the shredder. Your video on the 1/2 hp drive will help me in our project.

Correct, is the case of an old Power Supply, I just removed the electronics and it has plenty of room inside for the wiring of the reverse switch


Thanx for sharing! Indeed not enough torque from the 300W motor.

P.S. Electrical housing box looks like an old PC case isn’t it? another great idea for the community 😉

@davehakkens yeah, if I knew the 1/2HP motor would be that weak, I’d rather save a little more money for a more powerfull motor 🙁

Ahhhh that is a bummer @xxxolivierxxx! Thanks for sharing the video though, super useful for us to get feedback! Also shredder looks very well made 💪

Here you go:


@joseeduardofernandes Correct, mine is 1/2HP and it has troubles shredding bottles, that’s why I suggest 1HP or more

@z11aalex if you share more details we might help you decide if that’s a good motor, details such as torque, RPMs, horse power, monophase or triphase, might help to give you a better response

@sculptureclash Thank you. Mine is a 110v monophase motor, it works at around 1430rpm in 110v mode but the reducer slows it down to around 60RPM. The voltage of the motor does not really matter, what matters is the amount of HP/Torque and RPMS.

@jegor-m Thank you. I don’t think I need a glass window, I usually guide myself by hearing the motor shred and based on the sound (which is loud AF) I can tell if all the plastic was shredded or if the motor got stuck. Yes, I added a grill under the shredder. In the original design from Dave, you can attach and detach the grill, but on my shredder, I just soldered it to the shredder frame.

I’ll upload a video shortly