A post from Alby regarding problems with a Korean manufactured generator prompted me to post this. It would appear that the orifice of the generator nipple could be oversize. If you are into fettling I think being able to measure the size of nipple orifices accurately is essential. Broach Set. With the aid of a micrometer or a digital callipers and a set of watchmakers broaches, NOT brooches, it is easy to measure the size of an orifice to within 0.01mm. Broaches come in various sizes and they are used for resizing plates in watches and clocks. One set I have consists of 6 broaches for resizing holes from 0.15mm to 1.5mm diameter. The broach is inserted into the orifice and the diameter can then be measured. Note the broaches are not round but slightly oval. They also have a 1:100 taper. It is the combination of oval shape and taper that allows for the resizing of holes, Broach in small orifice Micrometer showing 0.19mm orifice Broach in small orifice. Enlarged 0.29mm orifice. If you are interested in the broaches a search of the web will return numerous hits. Go for the smallest available. Cousins UK have a variety to choose varying in price from ₤23.50 for a set from 0.05mm to 0.30mm.
That is very informative, @Jones the lamp . A quantitative measure of jet orifice diametres would come in handy.