After the old forum software breaking in a way that we were unable to fix, we've migrated the site to a new platform.
Some elements aren't working as we'd hoped - some avatars didn't survive the transition, and we're still having issues with attachments that weren't added as inline images, but we're hoping to have that all sorted out soon.
Really needed a destoner for the roastery, hand sorting 10kg of beans at a time is a laborious task Trouble with destoners is that they are a sizeable investment for what is a pretty simple product, 8k is a starting price for a traditional style and about 3K for a compact blower style.
After looking at lots of different designs and having a 200mm high powered fan in my possession I decided to build a compact blower style for myself.
So here's the prototype. Pour the beans in the top at an even steady pace, fan on full pushes the beans up the chamber and over the bend falling into a collection bucket, any stones stay in the tube and are prevented from falling down to the fan by the centre screen.
Took a little bit of trial and error with getting the tube lengths right and best position for the input. Prototype works like a charm small rocks, big rocks, green beans, whatever I mixed in was caught in the destoner screen every time.
For a small to medium volume it's perfect, most expensive part was obviously the fan, found that on the web with a discount code for $240 shipped, the rubber collar was $42 and fitted the fan and 90mm plumbers pipe perfectly. The plumbing fittings were a total of $45 add in the braces at $18, had the trolley wheels lying around and the timber was an off cut of the roasterys new table. $345 total cost, not too bad.