It is a 120 click 1 direction only. The video plans suggested with a GMT to remove the ratchet plate, but that required removing the bezel, which was more work (so I didn't).

 

So as an update to this: I've since put together 1 more ali-express watch, and there were a few quality differences in the case/dial/hands/etc. BUT, it is a half-decent looking watch.

But the real update: I put on my DIYWatch Club watch and wore it for a day and realized it was gaining time BAD. I popped it on the timegrapher to find that it was +150spd crystal up, and -80spd crystal down. I also noticed the amplitude is 160 degrees. I emailed DIY Watch Club yesterday, so we'll see what they do about it.

 

Wow! That's way, way out of spec. It would be great if DIY Watch Club gave you a replacement movement. However, that would mean you would have to disassemble your watch to install it. An alternative would be to regulate the watch yourself or get a watchmaker to do it for you.

 

@ErichKeane
Just had another thought. Could the movement somehow have become magnetised? You could run it through a demagnetizer first to see if that will fix it.

 

I had tried to regulate it (I bought a timegrapher so I could), but I think the low amplitude is the problem. I ordered a demagnetizer to give that a try, but I'm not particularly optimistic.

And yeah, I'm going to see what the DIY Watch Club says. Worst case, a replacement movement is ~$30, and I could just build it myself. I have already built 2 more NH34 based watches (~$110 in parts from Ali-express, a "Pepsi GMT" style and an "Explorer ii" style), so I'm getting less-awful at it.

 

So I FINALLY (3 days later!) got a response form DIY Watch Club that asked if the problem still reproduced on a bare movement, so after trying the demagnetizer on it for a few minutes to no improvement, I stripped it down. I got consistent readings throughout my disassembly, about 150 degrees face up, and a more sensible ~240 degrees face down, even as a bare movement.

I ended up getting in a spare movement for a different project, so I started assembling with that... BUT, I managed to mangle my last second hand doing so, so it is re-assembled and working well without a second hand, stable at about 270 degrees.

I ordered a bunch more sets of hands/backups/etc, so I figure I'll install the seconds hand in this, re-regulate the new movement, and wear it!

I WILL note that since I had it apart, I pulled the spring out of the bezel, so now the alignment of the dial/movement ends up being that much less important

I ALSO pulled the bezel off my ali-express pepsi trying to do the same thing, and am pretty sure I ruined it (it is a different style, so it doesn't re-assemble easily), so I ordered a new case from aliexpress. Neither of the GMT-Master clones will get much wear time anyway as I'm not a fan of the look of them,but mind as well get them complete

My Ali-express Explorer II Polar style though HAS had quite a bit of wrist time. It is a pretty attractive watch, and might convince me I need to buy the real thing!

 

@ErichKeane
Installing the central seconds hand on my watch was one of the most difficult things I've ever attempted. Amazingly, I managed to mangle only one. I did have to assemble my watch twice though, because the first time round the second hand kept catching on the minute hand. Good luck with the rest of your build.

 

A problem with these kit watches is that they use mass produced hand sets that are "close" to the caliber specifications.
On a number of builds that I've done I. found that the hands may require some adjustment. Usually broaching the seconds hand tube to fit the pivot.
The broaches used are the diameter of a human hair and upwards, and only tiny amounts need to be tweaked to get a correct fit.

So, unless the kit providers have done a fit check on all components, you may run into trouble beyond the capabilities of the novice watch assembler.

 

@DoctorEvil : I actually got pretty good at it! My other 2 watches (The Pepsi and the Polar) I was able to get the second hand on correctly in only a few minutes. The problem I had was removing the hands, I slipped with the hand-removal tool and mangled it.

@JimInOz : So far I haven't had to own a broach for these hands (and I've installed 4 separate ones, only 2 from this kit). They've all gone on reasonably easily. But perhaps I'm lucky