Fitting PL259 Plugs to RG8-X

Like many operators, I'm a regular user of the relatively low-loss RG8-X coax.  It's a lot nicer than using the very bulky, stiff RG-213, which has much the same loss characteristics.

It's always a bit of a question as to how best to connect coax to a plug.  Soldering to the braid through the plug holes is always prone to heat-damaging the inner insulator - damage that you can't assess because it's largely out of sight.

An old, dismantled RG8-X plug to coax connection.  The screw thread provides very good physical and RF coupling.

 
But it's very easy with RG8-X.  First, I use coarse aluminium oxide sandpaper (or a metal file/rotary tool head) to rub away a key to the base metal all the way round the outside of the bit that attaches to the outer sheath of the coax.  I then carefully heat the plug and add a thin layer of solder all the way around.  If you melt a blob of solder onto the tip of the iron and simultaneously let it touch the plug, this is a very good way to quickly transfer heat to the plug.

After the fairly long time it takes the plug to cool down, I strip the coax as usual.  I pull the outer braid back over itself, so that it faces away from the plug.  You can then screw the plug directly onto the braid and PVC sheath, which fits very snugly, without the need for excessive force.  This makes a very stable, secure and sound RF connection with the plug, as you can see from the years-old example recently disconnected.

To make doubly-sure of a good connection, I then wrap the remaining short length of braid around the tube of the PL259 that fits over the braid/sheath, and then apply solder, which attaches itself very easily to the plug due to the earlier pre-soldering.  Once it's cooled, add a layer or two of self-amalgamating tape to add some mechanical strength and weather tightness (if needed.)

You now have a bomb-proof RF connection to the plug!  I'll add some more photos of the process when I get a chance...