Open-Source, DIY Seed Cleaner Plans

Released for the benefit of small independent seed producers.

This design combines traditional zig-zag aspirator design with a 'swirl chamber' just below take-off
to allow repeated sorting of each seed as it is poured though.

Suitable for small seed (poppy, amaranth) to medium seed (squash, sunflower)

Construction cost was less than 5 GBP using scrap materials.
Using purchased materials cost would be under 50 GBP.

Remember though that this is only designed for small-scale batches: lots of a few grams to 10kg or so.
Bigger than that you'll need a different solution because the square-rule law applies - if you double the size you'd need 4 x the suction!

If you make one, please email us a picture of yours! We'll put them up here.

Seed Cleaning Machine Design by The Real Seed Collection Ltd
is licensed for public use under a
Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License

Important - read the link above before you make one.
Basically you can make one for your own use,
but you have to tell people where you got the plans (including a link to us),
and can't sell copies of the machine for a profit
You are free to adapt the plans and improve it - but the same rules then apply to the new design.

Thanks! Ben.


NOTE1: The bottom right chaff emptying flap needs to be airtight or the cleaner will not work.

But it also needs to be easily removeable so you can dump out the chaff quickly - you will need to do this quite often often,
for example when you suck good seed out by mistake and want to put it through again.

Ours is held on by 4 small supermagnets glued in holes in the wood.
Matching magnets set in the body of the cleaner attract it on firmly ; if the bottom of the cleaner is smooth it is airtight.

We have a tray / tub under it this flap, so we can just pull it open and all the seed falls into the tray for recycling if needed.


NOTE2: Don't be tempted to 'improve' the plans! If you build it exactly as the plans say it will work really well.
If you change anything, it might work better, but it will probably not work at all. Once you've built one and got a feel for how it works,
then of course you can play around with the design and maybe improve it some more.


Just wanted to say thank for the seed cleaner plans! I'm using it to winnow roasted coaco beans and seperate them from the husks. I did my first trial run today and it worked fantastic.
Caleb Olson

I recently discovered your plans for the home made seed cleaner and decided to try it out. Attached is a photo of the one I built. ... Thank you so much for posting your plans and the video- it was incredibly helpful and nice to be able to access those.

Prairie Wolfe, MPG Ranch

I found your youtube video and web page on the seed cleaner and made one up yesterday.
I left out the holes to adjust the suction and instead wired up a dimmer switch to control the speed of the vacuum. We will probably try it out this evening on the 10 gallons of amaranth that we didn't get cleaned from last year's harvest.
The front on mine is some left over double wall greenhouse plastic panels. The back is left over plastic corrugated.

George Adams

Good evening seed collectors,
the processing of our winter wheat was greatly speeded up after I had made the seed cleaner, based on your design. A picture goes as proof. Many thanks and if you ever consider the benefit of making a handthresher ...
With best regards,
Paul Liebelt

I saw the video Ben did and decided to get making one straigh away. I find it works best with smaller seed and sorting out the dust and chaff as well as the thinner ones. I will make a few adjustments to make it more air tight but I am very impressed and it's saved me a lot of time when it comes to cleaning seed I have saved myself. Maybe with a different powered hoover the results would allow me to clean up larger seed such as beets.

- Jack

At last we have finished the seed cleaner - it was my Christmas gift. We are most grateful to you for sharing your design and for the very helpful video.

The cleaner works perfectly except we have an issue with static electricity. It must be the composition of the acrylic sheet on the front. I have sprayed it with a solution of liquid fabric softener and that helps to reduce it somewhat. We added a carry handle and designed feet that fold up for storage. Think we'll make a larger funnel hole to allow for cleaning beans.

I am the person who contacted you about cleaning lettuce seed. The cleaner is excellent but I wondered about the height of the first wedge. If it were just a shade lower, the seed might not bounce up and be drawn into the outlet so easily. It's hard to say, really. I look forward to experimenting with next year's seed harvest and cleaning.

Thanks again - Frances

note from Ben: Yes, seed bouncing up from the first wedge into the vortex can be an issue. However, while moving the first wedge down might help, I worry it could destroy the 'swirl' effect. Instead, I would suggest moving or angling the funnel to the left more, so the first thing the stream of seed impacts is the _second_ wedge, on the left.

Greetings from Sao Paulo Brazil! I just finished my seed cleaner based on your design. I use it to separate my cocoa nibs from the husks and it works fine! Losses are only 17%!!

Many thanks for posting all the project in such greater details. It worked fine.

I attached a picture of the cleaner.

Best wishes,


PS: The machine you see on top is a coffee beans grinder that I use to crack the roasted cocoa beans. The beans are smaller than usual since I use native ones from the Amazon Rain Forest, which is collected by the locals from trees near their homes. There is no organised plantation! The coffee grinder manages to crack them rather well. Other crackers I used broke them too much and the recovery rate was smaller.

Usually, small chocolate producers like me use the Chocolate Alchemy winnower (The Aether Winnower), which achieves a recovery rate around 80%. The Real Seeds winnower of yours gives me 83% and occupy much less space then the one from Chocolate Alchemy. On top of that it is much nicer to the eyes!!

I attached a small 1/6 cv motor and speed control to the axis of the grinder to save time and increase productivity.

I want to thank you for the detailed plan you provided.
By following it carefully I've made my winnower work at the first attempt. It is wonderful. I believe it is "healthier" for the beans to drop on piece of wood than through plastic pipes.

Below is the end result after the first batch of cacao beans.
All the best to you.
Thanks again - Alain d'Aboville


Don't do this unless you're really sure you know what you're doing. . .

This is one I spotted in a blog about Humming Bird Chocolate. Looks like its been modified with the addition of at least 2 extra vacuums to take away the debris and feed in cocoa nibs.

I would suggest thinking carefully about how its going to work if doing this - you'll get 'interesting' effects of the suction in different directions!

The original design assumes open air pressure at the bottom left and a closed-off collector. Stick to this unless you really understand how it works.

Note the ear-defenders!!!

Dear Ben,
Just finished my first seed cleaner and wanted to send you a picture to add to your collection. I am in Uxbridge, Ontario, Canada and I am using it to separate the cocoa nib from the hulls and it seems to be working well. Can't thank you enough for posting the design online.
Best regards,

Hi Ben,

Attached is a photo of the seed cleaner I built from your plans. I use it for cocoa beens and it works great. I am about to make a demonstration video using it. Most people who see it working just smile in amazement. Thanks so much sharing the plans.

Best Regards from California, USA,

Thomas Snuggs

My husband and I wish to thank you for sharing the seed cleaning plans. We asked a friend from Montreal (Alex McLean) to build one for us and the result is amazing. The seed cleaner conception is fantastic and thanks to Alex's thorough work the result is absolute perfection.

It seems that the seed cleaner works well for artisanal chocolate producers - after all, chocolate is a seed, and you need to sort the seed husks out from the beans. Here's Maria Madero's version from Mexico.

"Thanks for sharing the winnoer desing. Its very usfull for my chocolate factory in Merida Yucatan Mexico. I made it out of stainless steel. It works great! the cacao nibs are super clean!!!"

"I just wanted to say thanks for posting the design. I just finished mine last night. I spent about 6hrs on the project - I can't wait to use it." Andy Rodosevich

Here's one in use at Durham University, by Dr MacGregor:

"Just wanted to get in touch to thank you for the plans for the vacuum seed sorter. I had one made by the Durham University school of Engineering Mechanical Workshops this summer and I couldn't be happier with it. It is working amazingly well. Photos attached.

Thank you! - Dana"