Strange wobble in Manfrotto 700RC2 head (1 Viewer)

[Jim M.]

I have a Kowa 883 attached to my Velbon CF630 tripod legs via a Manfrotto/Bogen 700 RC2 tripod head. I have had this set up for about four months. Ever since I have had it, when I loosen the knob to permit horizontal panning (but still have the knob for vertical tilt tightened), a vertical wobble is introduced so that when I grab the pan bar I can rock the scope about 3/8 of an inch up and down. If I tighten the knob to prevent horizontal panning, this vertical wobble disappears.

Does anyone know exactly what is going on and how I can prevent it? Do others have similar problems?

Thanks for any help,
Jim

 

[Henry B]

Have you got the plate the correct way round.

 

[Jim M.]

Have you got the plate the correct way round.

Hi Henry,

If you mean the "quick release plate", I think that is fine and there is no wobble in that area. The looseness appears to be near where the head connects to the tripod legs (which is also the same area where horizontal rotation occurs).

Cordially,
Jim

 

[Alexis Powell]

Jim,
I think I know exactly what you mean. I had a very early production 700RC2 head. It was recently replaced with a new one by Bogen. My original head did not have play in it when either the vertical or horizontal pan knobs were loosened, but it also had a _very_ stiff action that got even stiffer in the cold. I noticed that newer 700RC2 did not have this stiffness problem and finally got around to sending my head in to Bogen. They (generously, at no charge) tried to fix the old head by repacking it and loosening it, but as a consequence it lost all its fluid action (was _too_ loose) when the knobs were not partly tightened. I sent it back and they sent me a new head. It is clear to me that the new head is a slightly modified design. I can see the edges of white plastic (teflon?) pieces in the vertical "fluid" control (the original design had a direct aluminum on aluminum interface with silicone grease sandwiched between them). When I loosen the vertical pan all the way, there is enough play between the disks that there is a horizontal wobble. I presume the horizontal pan control works the same way (I can't see into the edge of it) because when it is loose I get the vertical wobble that you describe. Unfortunately, it seems that the latter wobble only goes away when the knob is fully tightened. My old 3126 head has both wobbles, but it is easy to tighten the control knobs enough to remove the wobbles yet still have a light fluid action in both movements.


All in all, I much prefer my wobbly new 700RC2 to my old stiff one. The horizontal wobble is not a problem because it can be dialed out, but I do wish the vertical wobble could be similarly controlled.
--AP

 

[Jim M.]

Thanks for the confirmation Alexis. Sounds as though I may just have to live with it.

Best,
Jim

 

[widow57]

Jim
I've experienced exactly the same problem. It started when I noticed that the pan handle was actually turning the centre column on the tripod because it was too tight. Now, the two parts of the head are connected with a bolt which takes an Allan key and this is accessed by removing a plastic cover at the back of the head. I loosened the bolt slightly so that the pan was smooth but very soon the bolt loosened to the point where the condition which you describe occurred. This is a Catch 22 - too tight and the pan locks completely, too lose and the wobble occurs. I spent a long time (this last weekend in fact), trying to resolve the problem. The bolt needs to be set at a point where it will allow panning with no wobble, and then locked at this point. With considerable precision engineering, it would be possible to drill through the mount and into the bolt, then inserting a pin so that the bolt cannot rotate. Setting the bolt at the correct position is difficult as the head needs to be in place for the setting up but removed for the drilling. If you are a precision engineer you may be able to achieve this, if not then try making the threaded hole tighter so that the bolt cannot work loose. The plastic cover will actually prevent the bolt from working at too far anyway, so the head won't actually drop off. I tried thin plastic in the hole and this worked, but I then moved on to PTFE tape, which also worked but I ran out of it after my initial test. Eventually I dropped super glue down the hole and quickly replaced the head and set the bolt. Not too much glue though, or it will spill out and glue the head in place permanently! It works, but for how long I do not know as super glue does not stick metal but at least it should be up into the thread. That's the principle - you may come up with a better idea. I'm pleased that I'm not the only one having this problem; Manfrotto have not been helpful and this is quite obviously a design fault and is very disappointing. Good luck. Let me know how you get on.

 

[Jim M.]

Thanks for the info widow57 (and welcome to the forum). I actually am now using a less expensive head, the Velbon PH157Q, and am quite pleased with it thus far. My 700RC2 basically lost the ability to tighten the tilt function. This is probably due to the fact I prefer to carry my scope/tripod upside down by my side while grasping the pan handle--and that puts a lot of stress on the tilt mechanism. I tried a 701RC2 but found it had a design flaw also--it has nothing to prevent the QR plate from popping off the top except pressure on the sides of the plate, which is not enough to keep it on if scope hits the ground. So far the Velbon head seems quite sturdy and I love the easy set up made possible by being able to tighten/loosen both tilt and pan functions with the twist of a single handle.

Best,
Jim