We ended page one with the question, how do you side load a compressed air couplers and connectors?
It's very easy to do. If you are using an air drill or grinder or air nailer or any air tool that has its connector plugged into a coupler on the air hose, it is almost impossible not to impart a sideways motion to the coupler-connector connection as you are using the tool. In so doing, you are side-loading that connection.
When that occurs, the coupler/connector can leak, particularly if it is a low cost set. You will hear the connection hissing, and in so doing, bleeding compressed air, the energy that was used to compress the air, and the money you spent on that energy, to atmosphere!
Some couplers even offer additional functions such as an integral relief valve to vent trapped compressed air safely before disconnecting the coupler from the connector, a considerable improvement over popping the two apart when there is air trapped in the line.
For most DIY users however (including myself) the low cost of our couplers and connectors offset the annoyance of periodic leaks and connection foibles, though I sure do curse the darn things from time to time.
The grunting is from the person who is trying to hold the coupler, slide the knurled ring back towards the hose with the same hand, and at the same time trying to insert the connector into the coupler with the other hand.
Escaping compressed air provides the hissing, while we grunt, trying to get the darned things to connect. It seems that we never have enough hands.
When the connector is inserted / seated all the way, you release the knurled ring on the coupler (not the coupler itself, just the ring) which is spring loaded, and it snaps forward. You then, carefully, ease off on holding the connector just bit, until you are sure that it has been captured by the coupler.
Don't let go of either component completely until you are sure they are mated. Sometimes they pop apart, with a lot of hissing. Been there and done that!