In order to inexperienced hands podmotat thread it is necessary to prepare in advance. The fact that a smooth thread poorly kept sealing material - flax (preroll). Well, if the threads prepared in advance by the manufacturer. While flax does not slip, sitting in place and tight connection is obtained. The photo below shows the difference in the thread. One combined clutch is smooth, the other grooved.
The new thread in the foreground has transverse grooves. For them mastic is clinging material, and does not slide off when twisting in the other parts.
Unfortunately, manufacturers do not often rolled thread, for them it is an additional cost. Therefore, there are two ways to apply transverse grooves, one schadyashy second dangerous, that's like this part, look the photo below.
The first method
More gentle method of applying lateral grooves can be done with a file.
Files need to scribble across carving small grooves. By mikrozausentsy mastic is not allowed to slide content.
The second way
Cause many mixed opinions, but this method also has a place to be. For application of transverse grooves need a pipe wrench, preferably a relatively new zaklennymi with sharp edges, sponges.
In order to apply you must compress the incision thread pipe wrench. Neatly.
After these manipulations, the thread can be discarded unnecessarily it will be spoiled.
Important
1) crimping should be done with not much effort.
2) Pay attention to the thickness of the walls of the thread, if it is thin there is a risk of damage rezby- become oval.
For experienced plumbers presence of transverse grooves does not really matter. One can pack tightly thread and without causing burrs. Information is given for beginners and home craftsmen.
As the mastic is a plumber flax, see the continuation of here- link.
For those who do not know I've been working as a plumber and part-time blogger. Therefore Like workaholic for the valuable information!