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guym-p
7-Jun-2008, 02:28
I have used a Sinar P2 for years. Recently, I had a job where I could not get a car to the site (or hire a team of sherpas) and had to hike. I bought a Sinar Norma as a light-weight, man-portable, alternative.

What a beautiful thing the Norma is! The P2 is a wonderful tool once it's in position, and a doddle to set up, but I can see myself using the Norma more frequently.

I have a question for experienced Norma photographers. In their zero-detent positions, the standards are not parallel, nor are they perpendicular to the rail. It's not a major issue in use, because all the movements are smooth and tight, and I used a small level to get everything true before shooting, but it would be nice to get it right.

Are Sinar Norma tilt detents adjustable?

Yours,
Guy Montagu-Pollock.

Frank Petronio
7-Jun-2008, 05:37
Yes but I don't know how and my repair person told me that most amateurs will strip the threads if they are not careful. So be careful and use the right tools!

snuck
7-Jun-2008, 06:27
given that I'm a recent convert... what's the most common way that threads get stripped?...

Cheers

guym-p
7-Jun-2008, 08:59
The screws are aluminium going into aluminium, so it's incredibly easy to over-tighten them. They can only handle a fraction of the torque of a steel bolt into steel, so don't give a huge twist where a small nip will do.

It's common with aluminium to use thread adhesive (eg Loctite) to prevent screws working loose. Sinar use clear lacquer. With time, it becomes so hard that you risk damaging the thread while removing the screw, not just tightening it up. If that happens, you need to clean the thread thoroughly, and be doubly careful not to over-tighten them during re-assembly.

I am fortunate that before I became a photographer I was in engineering, so, to a certain extent, I know what to expect, and I had the right sized-tools. The Norma I bought needed cleaning. The grease had grit in it like grinding paste, and I could feel it, so the job was pretty urgent. Now it's clean, tight and works smoothly, so it was worth doing. If it had worked smoothly at the outset, I would have left it alone.

In the same way, I don't want to attack the screws near the tilt-detent ball-and-spring if there's no benefit. If someone's successfully adjusted them before, I'd be grateful to know.

Guy.

guym-p
7-Jun-2008, 11:16
Solved!

I should have had a bit more courage at the outset.

At the foot of each riser are three screws. One black, parallel to the tilt axis, and two polished ones. The black one is in fact the ball assembly - a rubber rod with a ball bearing on the end, and a slot for a screwdriver at the other. The ball assembly is not threaded, it's pinched tight by the two polished screws (shown below). These screws were incredibly tight on my Norma.

http://www.montagu-pollock.co.uk/images/_GP34046.jpg

The ball is mounted off-axis, making the ball assembly a cam. Slackening and twisting the assembly moves the ball very slightly, which adjusts the detent position.

http://www.montagu-pollock.co.uk/images/_GP34056.jpg

There is also a good deal of tolerance on the riser flanges, which are held by two button-headed allen-key screws, so I found the best procedure was to make a coarse adjustment on the flange, followed by fine adjustment with the ball/cam.

I'm delighted to say both standards are now true, and all bubbles are accurate.

Guy.

Daniel Unkefer
8-Jun-2008, 14:15
Invaluable Norma Information.
Many Thanks!
-Dan