Am working on several builds, one of which is making use of three brand-new polished black CCM fittings, recently ordered direct and received, and attempted to install tonight.
The fittings look amazing, and appear to be flawless in every respect. Major kudos there.
However, when I attempted to do some dry test fitting, I found that none of the three will thread in more than 1.5-2 turns into any of the air ports on the marker. Am not attempting to crank them down. They just come to a stop, as usual NPT threads do, and make it clear they aren't going to budge further without application of force, and I'm not going to do that.
This leaves lots of threading hanging out, and the fittings sit high.
The threads look and feel clean, and the parts into which they are going are also clean.
All the installation videos I've seen show these being able to get right up close to the part into which they are threaded, even with Loctite or teflon tape on the threads. Indeed, the video posted by Tf/Socrates Jones indicates that the fittings can be threaded in so far that they make contact with the marker.
Yet I'm looking at more than an 1/8" gap, which is more than the regular old brass fittings gave me.
The parts into which I'm threading these are excellent condition, and some new. I've tried older parts, with the same results.
Can anyone explain this? Has CCM changed designs? The videos I've seen from several years ago show a different wrench configuration, outside for the older and inside hex for the newer, so at least some things have changed. I always figured they didn't use normal NPT threading, to allow them to screw down so low.
EDIT: After a little more thought, am wondering if the posts are nickel plated brass, and if so, if the plating is simply a little thick. The hex key provided (great touch!) really protests at going in, as do my own keys, and in some orientations will not go in at all.
If that is the case, perhaps it may do to put these through a die to check them, and ultimately, to get them into shape.
This is of course assuming the issue is the plating.
But either way would like to hear from the experts here first.