Cafe Rosto problem

[briadea]

I have used a Cafe Rosto for almost a year now with few problems. Lately, however, when I roast my beans about 15% of them are not fullyroasted, while the others are done very well. I don't know why this should be. Maybe the blower is not strong enough and needs a costly replacement.

Any ideas out there?

 

[Robert Deason]

Sounds like a poor circulation of the beans. When they don't rotate freely, they come out unevenly roasted. I find that some beans, more than others, swell up as soon as they feel heat, and they stop circulating, and the ones nearest the center heat source get burned.
You probably know not to use the measuring cup that came with your machine; it's way too big. Reduce your input then watch the beans. If they spin so much that they're thrown into the chaff catcher, add a few more (10 or so) and watch. There's sort of a critical mass where they settle and circulate evenly. If the beans swell and stop half way through the roast, I'll pick up the Rosto and shake it gently in an up and down motion to aid the circulation.
I've had mine for two years, and roast nearly every day, but I've had to open it up and give it a good cleaning and oiling about every six months. Here's where the Rosto has a plus advantage, you can get into it. -Rob

 

[briadea]

Cafe Rosto

Thank you for your excellent reply. To be honest, I got tired watching my half-roasted beans so I bought a more expensive, I-Roast machine. The beans are roasted evenly and perfectly and there is no smoke. That helps, because I like to roast indoors.