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View Full Version : Sinar Pan/Tilt - I think the thread is stripped



mrpow
27-Feb-2012, 09:47
Hi Everyone,

I bought a used Sinar Pan/Tilt last year from KEH. It's been great for the past year but now my tripod is having a hard time staying in, in fact, it won't catch on the threads at all. I've emailed Sinar to see if they can suggest anything and unfortunately, I'm past the warranty with used gear on KEH. Has anyone had a similar problem with a head like this? I love the sinar pan/tilt because I'm using it with a sinar 4x5 (perfect combination) so I would hate to have to find another one. Any help would be much appreciated. Thanks!

rdenney
27-Feb-2012, 10:27
Hi Everyone,

I bought a used Sinar Pan/Tilt last year from KEH. It's been great for the past year but now my tripod is having a hard time staying in, in fact, it won't catch on the threads at all. I've emailed Sinar to see if they can suggest anything and unfortunately, I'm past the warranty with used gear on KEH. Has anyone had a similar problem with a head like this? I love the sinar pan/tilt because I'm using it with a sinar 4x5 (perfect combination) so I would hate to have to find another one. Any help would be much appreciated. Thanks!

Can you be a little more specific?

Which threads seem to be stripped? The mount to the tripod legs? The pan lock? The tilt lock? The universal screw to the rail clamp? The lock lever for cinching down on the rail clamp?

Rick "lots of threaded connections on one of those puppies" Denney

Leigh
27-Feb-2012, 11:27
Some tripods have a two-part retention screw, with a scalloped nut threaded onto the shaft.
If this nut is too far forward it will prevent the screws from engaging the camera or other device.

If your tripod has such a nut, be sure it's backed off all the way (toward the screw head).

I can't imagine that you stripped the threads in the pan/tilt head unless you're a real gorilla,
or the threads were only marginally engaged from the beginning.

- Leigh

mrpow
28-Feb-2012, 03:52
Can you be a little more specific?

Which threads seem to be stripped? The mount to the tripod legs? The pan lock? The tilt lock? The universal screw to the rail clamp? The lock lever for cinching down on the rail clamp?

Rick "lots of threaded connections on one of those puppies" Denney

The thread in question is on the bottom of the pan/tilt head - the one that connects to the tripod screw. (can be seen here (http://imgur.com/TFWSl)).

It seems that if my tripod screw was just a little longer it could catch on the thread - is there a company that makes some sort of extension? You can see here that the camera mounting screw can catch - (can be seen here (http://imgur.com/DbNyJ))

I'm using a manfrotto 055XB with the Sinar Pan/Tilt head to be more exact.

Thank you again for the help

Leigh
28-Feb-2012, 09:45
Well, you stripped the threads out of the bushing.

The only solution to that is to replace the bushing.

Your tripod screw does have the scalloped nut as I mentioned in post #3.
That needs to be backed all the way out, so it touches the screw head, before you mount the pan/tilt head.
Run the screw all the way in as far as it will go, then tighten the scalloped nut to finish the installation.

You can buy a longer screw at any DIY or hardware store, like Lowe's or Home Depot, for about 50 cents.
The screw should go all the way into the bushing. You might still have enough thread left for it to work.
The thread is 1/4"-20.

- Leigh

Peter De Smidt
28-Feb-2012, 09:47
Contact Precision Camera Works: http://www.precisioncameraworks.com/Pages/services.html

rdenney
28-Feb-2012, 10:22
The proper fix would be to restore the threads in the head where they are stripped. A longer screw to catch one thread will eventually strip it, too.

That center threaded section is part of a larger bushing that is attached to that base plate using the three screws you can see from the bottom in your picture. It is made of steel and I think attempting to repair the threads would be pretty challenging. The number for that part is, I'm nearly certain, 516.41.517. That's for all the versions of the tilt-head starting with 516.41 version 1001-1d, ca. 1992.

I have the similar part from the original 1979 version, but it's not the same part, unfortunately.

If you can't source the part affordably from Sinar, then you might be able to have a replacement machined by someone like S. K. Grimes. They might also be able to restore the threads using an insert (Heli-Coil is one brand), but I'm not sure there's enough material to allow room for an insert.

I don't know how that mounting plate is attached to the tripod. It is certainly primarily held in place by the 3/8-16 bolt, but it may also have a collar that extends down into the column and is held in place using set screws of some sort. I think I have a similar tripod at home--I'll try to remember to look. There is no practical way to extend the bolt, and the impractical ways still require removing it, so you might as well just replace that threaded section with something longer.

Theoretically, you need six threads of insertion for full strength. It looks as though the most you'll get is two. I'd be satisfied with four.

Rick "good luck" Denney

Dominique Cesari
28-Feb-2012, 11:11
You may want to download : http://image2output-support.com/downloads/sinar/View%20Camera%20Service%20Manuals/Accessories.pdf

E. von Hoegh
28-Feb-2012, 11:20
Also, when you get a new part - or repair the old one - make sure you are engaging threads equal to at least 1 1/2 diameters of the screw. Many of these things strip because ther isn't enough thread engagement.

mrpow
1-Mar-2012, 11:00
Thank you for all of the help.

I contacted Sinar and Manfrotto. Sinar referred me to specialists that could deal with the problem but the specialist looked the most confused.


That center threaded section is part of a larger bushing that is attached to that base plate using the three screws you can see from the bottom in your picture. It is made of steel and I think attempting to repair the threads would be pretty challenging.

Yes, it seems very impracticable to replace this but I will look in to S.K. Grimes - Thank you.

The Second picture was only suppose to be a reference picture of the how the mounting screw was still able to catch the threads. Unfortunately, both the low angle adapter and normal tripod mounts are not tall enough to catch.

It really is the perfect head for 4x5 for me at least. I've found it very practical in situations and to those who have a Sinar know how compact a head must be to be used with the camera. In the meantime I will just mount the camera directly to the tripod until I return to the US in the next couple of months. Can anyone recommend an affordable head to be used with a Sinar F1 and a manfrotto tripod?

Thank you again for all of the help, I really appreciate it.

Mike

rdenney
1-Mar-2012, 11:57
The cheapest head that is adequate is the Bogen 3047. These regularly sell used for under fifty dollars. They use a hex plate, which is barely usable on the Sinar rail clamp, but it does work. The Manfrotto 055 is a bit light for a 4x5 monorail, in my opinion, so I'd be tempted to mount the camera directly to it and use the leg extensions to level things up. A tall head will just increase the bending moment on the legs and magnify motions.

Replacing the damaged part is not impractical at all, by the way. This is quality equipment that is made to be serviced. Granted, it may be impractical where you are at the moment.:)

Rick "who'd be surprised if Sinar doesn't have the part, though they may only supply them to technicians in their repair network" Denney

Leigh
1-Mar-2012, 12:27
I can't look at mine right now because it's supporting my 8x10 F2.

If the threaded part can be removed, it would be easy to repair the threads.

The standard solution here in the US is Helicoil inserts. Any decent auto repair shop will have them in 1/4"-20.
You drill out the damaged threads and thread the hole with a special tap.
Then you screw the insert (looks like a spring) into the new threads, usually with some Loktite to hold it in place.

Once the Loktite dries you have a new threaded hole of the proper size and pitch.

- Leigh

rdenney
1-Mar-2012, 12:57
I can't look at mine right now because it's supporting my 8x10 F2.

If the threaded part can be removed, it would be easy to repair the threads.

The standard solution here in the US is Helicoil inserts. Any decent auto repair shop will have them in 1/4"-20.
You drill out the damaged threads and thread the hole with a special tap.
Then you screw the insert (looks like a spring) into the new threads, usually with some Loktite to hold it in place.

Once the Loktite dries you have a new threaded hole of the proper size and pitch.

- Leigh

Leigh, these are the threads into which the tripod legs screw. The threads are 3/8-16, not 1/4-20. The threaded portion is a collar that projects down like a bushing from a upper part of what clamps the main casting. That upper part and the platform through which that bushing projects sandwich the main casting allowing it to rotate. The upper part is steel, but that bushing/collar shape is not thick-walled. From looking at the service manual, I am not sure that the walls are thick enough to allow drilling and tapping for the larger threads required by a Helicoil.

Did you notice the posts where these parts were described in detail, including the provision of part numbers?

The only 1/4-20 threads on the tilt-head come out the top, with the special reversible (both 1/4" and 3/8" threads are provided) thumbscrew that Sinar provides for screwing into the camera's rail clamp.

Rick "who was looking at the pages in the service manual when typing" Denney

Leigh
1-Mar-2012, 14:32
Hi Rick,

Helicoils are available in 3/8"-16 also. That's the thread on mine, but I've seen them with 1/4", possibly reducers.

As I mentioned, mine is presently in use so I can't look at it closely.

The only alternative to the Helicoil would be to buy or fabricate a replacement part.
Certainly higher cost than the Helicoil repair (if that's feasible).
Just trying to provide options with which the OP might be unfamiliar.


- Leigh