Difficult

Well, the small research I was able to conduct leads me to think that manufacturing baking soda is a great deal more complicated then making vinegar. One would almost need a chemistry degree to understand most of this stuff, though experience probably helps. Here's an Old Article which explains the difficulty:

Pyongyang, March 19 (KCNA) - Korean scientists and technicians created a new effective method of producing baking soda with less labor. They succeeded in making the baking soda production easy through the use of dust from cement kilns as the country is suffering from the shortage of electricity and most of chemical factories are not in proper operation due to economic difficulties in recent years. Previously, the production of baking soda depended on the ammonia industry. Potassium carbonate is collected from the dust of kilns and put in water before salt treatment and blowing of low-pressure carbonic acid gas into it. Then, its reaction produces crystals of soda. When they are filtered, medicinal and edible soda is obtainable. Crystals of potassium chloride can also be made when the filtered liquid is concentrated and cooled. In this way, potassium chloride urgently needed for medical science is produced. This method is attracting attention of experts for its positive role in preventing environmental pollution.

All that seems way too heavy for the "primitive user". Meanwhile I found out that baking soda manufacture was probably one of the earliest Chemical Industries. And also it appears that mixing baking soda, which is a chemical base, with vinegar, which is an acid, causes a gas to be released which can blow up a sealed bottle. So whatever you do - be careful, if you're not into Molotov cocktails.

Offered by Sol.