[Coffee-Roasting9] Learn about roasting machine structure

Today I will try to disassemble the roasting machine easyster300 that I am using. In fact, it was too old to clean the drum and decided to clean it. I had a problem that the usual roasting profile was too frequent and I could not get enough heat. I kept thinking that it was a roasting machine problem and I had to change the machine. Then my coffee coach told me that you need to clean the drum. The smell of old bean oil is coming out of the beans, and he gave me a warning that there was a lot of burned oil on the drum surface. So I decided to clean the machine today.

When you look at easyster, many hex screws are protruding out. Remove these screws one by one with a hexagonal wrench so that they can be easily removed. This is a good example of the meticulous and rational nature of the artist. The hexagonal screws that hold the front plate, side plate, and back plate are different sizes. The hexagonal screws fixing the front plate are the same, the side plate fixing screws are the same, and the rear plate is also the same with the different screws, making it easy to distinguish according to the application.

When dismantling, set the necessary equipment in advance and remove the screws one by one.

I will remove the front plate because the drum cleaning is the main purpose. You can easily remove the front plate by unscrewing the hex screws one by one on the front plate.

If you remove all the components on the front panel, it will look like the following picture.

On the inside, 304 stainless steel was completely burned out. These burning oils had a direct negative impact on the beans as they were heated. I was surprised to see the front plate, but I could not help but be astonished when I saw the inside of the drum.

Drum photo. When the green beans are put in, the drums rotate and mix the beans evenly and heat them. The wing-like structure inside the drum is called a stirring wing. The stirring wing mixes the green beans more evenly, so that all the green beans that are introduced will be able to receive the heat evenly. The most important part of the roasting machine is the material of the drum and the shape of the stirring wing plays an important role in determining the quality of the roasting.

Many roasting machine manufacturers are doing their best to make the drum so that the temperature inside the drum is kept constant and suddenly the rate of temperature rise does not fall. Easyster300 adopts 304 stainless steel single drum because of low capacity sample roaster, and commercial roasting machine is mainly made of double drum structure and is designed to provide stable heat supply and preservation.

If you look inside the drum, you can see that it has a black coating. It's not a black coating, it's a burning of bean oil. Originally, the color of bright stainless steel should appear. I did not manage very well. However, I have blamed the equipment for an excuse for unsatisfactory results. I think I am still a lot lacking and there is a lot to learn.

The exhaust port connected to the top of the drum. The new heat enters the rear hole of the drum and the heat inside the drum exits through the exhaust vent. Here too, the dust, chef, oil and other substances from the bean sprouts are attached to the inner wall. All of these problems cause a decrease in thermal efficiency and a bad smell, which causes the low quality of the roasted bean.

It is necessary to remove the drum completely and clean it. To do this, it is necessary to separate the motor and the drum shaft of the main body. If you look at the picture below, it is very simple structure, easy maintenance and management.

There is a 1.5mm hex screw (pupa screw) in the picture. The drum shaft is easily removed by loosening it with a wrench. If you remove four 1.5 mm hex screws and two 3 mm screws, the drum shaft will be pulled forward.

Place the drum in boiling water. It is not easy to erase a lot of tainted marks. In the worst case, you need to scratch with a flat screwdriver or a chisel.

I used the baking powder + vinegar to clean the inside of the drum with warm water. In places where the hand can not reach because of stirring wings, we put a scrubber in the stick and cleaned it. The unremoved parts are scraped off or finished using a stainless steel abrasive.

There was some soot, but I could almost remove it. It seems to take about 3 hours in total. I think I'm going to get hurt ..........
When the stain is cleaned, it is necessary to thoroughly wipe it with a dry cloth. Soot powder or fine stain powder may remain. And the stainless steel is not likely to rust directly, but because the stirring wing is welded, the welded part is easy to rust. After thoroughly removing the dewatering and wiping work, we conducted test roasting.

It was very easy to supply calories. Early turning points were advanced and roasting was possible with less gas heat. We were able to see how much of the existing burnt nose and debris impeded the supply of heat. And the old smell of grease was no more, and a mild fragrance developed over 24 hours. Rapid lowering of the temperature in the drying stage has been almost solved, and the initial thermal efficiency is good enough for past roasting. Nowadays, I am doing research on gorgeous flavor using fast roasting and I was satisfied with the results.

I once again felt the importance of management. It seems to be a precious work that I have once again reflected on my ignorance and indifference. Thank you very much for reading so far. :)