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Arri 416 OBB-2 Battery Info


Dennis Toeppen

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Howdy All,

 

Newbie here.

 

Just made the switch to Super16...bought a new H16 RX5 S16 from Chambless Cine, an Arri 416 from a fellow in Dueseldorf, Germany, and an A-Minima from someone in the UK. The results from the Arri/Zeiss combo blew me away. The A-minima seems kind of finicky as far as film stock - E100D won't run without jamming. And, of course, the Bolex is as solid and reliable as it could be.

 

Rather than scannning everything I shoot, I thought I'd get a Super 16 projector. Since the optics on all my cameras are centered, it seemed to make sense to want a projector with centered optics. So I contacted Bernie at Super 16, who I've used before with mostly frustrating results. Since projector conversions seem to be one of his main lines of business, I figured he might be able to give me what I need. I asked Bernie which Eiki projectors can be converted with optics centered, and he told me, "Any Eiki". So I bought a nice Eiki and had it shipped to him. After the work was complete, in his mind, he called me to tell me that he could not center the optics *on that model*. I reminded him of our initial conversation and asked why he called me *after* he'd milled the gate out, rather than before -- because my options for solving the problem were quite constrained once the projector had been messed with. Things went down hill from there. He's now holding the projector hostage and demanding payment for the botched/incomplete/impossible job, and he's changed his story to "No Eiki" can be converted with centered optics.

 

So here I am, a month later, with no Super 16 projector, wondering what to do. I'd like to spend between up to about $1200, or maybe slightly more, for a high quality, ideally self-threading Super 16 projector with optics (and hopefully, illumination) on the same axis as the frame. Xenon would be ok, but I think I'd prefer halogen. I'm not a big fan of projectors which require assembly, as opposed to unfolding, like some of the old Bell & Howells.

 

Also, I'm sort of curious what people do when their 24v Arri on-board cell packs go belly-up. The only options seem to be:

 

- buy a new cell pack from arri for $850ish with 2-3 mo lead time

- buy an aftermarket cell pack from cinepower.com

- use a power supply which is not on-board

 

Thanks in advance for any tips on projector conversion!

 

(ps I'm not really a student...wasn't sure which category to select...)

Edited by Dennis Toeppen
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Hello Greg,

 

It's sort of complicated. I did disassemble one. It took me something like 3-4 hours. Most of that time was spent scraping sikaflex/urethane caulk out of the enclosure. The cells are Sony US18650V, which is a discontinued cell. One feature of that cell is that it is free of drift. I can't use cells which are not free of drift, because they are wired 8S2P, meaning there are 8 sets of 2 cells in parallel. I have inferred that free of drift means that the pairs of cells in parallel won't do something undesirable? So the first problem is obtaining discontinued cells, or finding something similar sans drift.

 

A second problem is that new DOT regs apparently prohibit common carrier shipping of lithium cell packs which are not connected to a protection board. This means that I can't get anyone to spot weld strips onto cells to make them into a 5-6-5 pack, as is needed for the battery pack. I can have them assembled, but would have to pick up in person.

 

That leaves me with buying 8 higher-capacity cells and a protection board, and putting those in the battery pack. That doesn't seem like a horrible idea, but I'd certainly prefer to put it back together exactly as it was when manufactured by Arri. Also, the only protection board that I can find to fit the Arri OBB-2 has a 5 week lead time.

 

What I'd really like is to send packs to someone and have them do it, in exchange for payment. :-) That way, I can focus on doing what I do best -- whatever that is.

Edited by Dennis Toeppen
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Hey Gregg,

 

I'm not sure. The Sony replacement US18650V3 is apparently not drift free, according to a cell dealer in Germany that I've been in contact with. I'm not sure how to determine whether a cell is drift-free or not, which is exactly why I'm nervous about this :-)

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I've never heard of this "drift" thing with regard to lithium-ion cells. I'm not aware of any problems wiring them in parallel configurations in general, but you should check the datasheet of any cell you consider for the task. I would imagine most manufacturers would expect people to use them in parallel configurations but you should probably check. It is desirable that the cells be of performance that is as closely matched as possible, which may be what's being referred to here, but there will always and inevitably be some small variations.

 

 

 

P

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Thanks, Phil. I wasn't very precise above. The configuration is 8 parallel pairs in series. I think the issue is the balancing of each pair, but again, this is just an assumption based on my instincts. It turns out that the V3 cell (the newer version) is also free from drift. The fellow in Germany emailed me today and blamed the misunderstanding on google translate :-) So I'm getting one V pack and one V3 pack from him. I'm anxious to see if they work well. I'm anxious to get my Arri up and running again.

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  • 4 weeks later...

Update: Cell packs received from vendor in Germany and installed in OBB-2's and everything is working great!

 

If anyone out there wants to re-cell an OBB-2, here's what I did. Please don't try this unless you're really comfortable tinkering with electrical things that can explode in your face and burn down your whole town. Please don't blame me if it doesn't work out -- I'm just telling you what I did, not what you should do.

 

- carefully take the lid off the OBB-2, just using your hands and fingernails. a screwdriver may damage the case.

- cut off the shrink wrap around the cell pack as best you can without damaging anything else.

- using a flat-head screwdriver, pry under the second row of cells on the end away from the power connector. be very gentle, so as not to damage the battery pack casing. rock the cell pack a little. use a great deal of patience. eventually, the cell pack will rotate out of the casing.

- next comes the awful part. using a small flat-head screwdriver, carefully dig the urethane caulk out of the bottom of the cell casing. the bottom of the casing has a web of ridges that form little triangles. if you get under an edge, you can sort of flick out a whole triangle at once. it took me about 2 hours to get all the caulk out on my first pack, and about 1/2 hour to do the second one.

- wire the new cell pack up as close to exactly the same as the original as possible. if you use desoldering wick on the old one, you won't use any wire length. be sure to protect things with heat-shrink tubing, just as arri did. for extra safety, i added some electrical tape anywhere a wire was in contact with the nickel strips connecting the individual cells.

- glue the new cell pack into the obb-2 casing. i used a lot less than arri did, so that i can get it out much more easily next time. i hope i don't regret this decision.

- after it dries thoroughly, put the lid back on.

 

I wasn't sure what I was supposed to do next. I charged each pack for about 24 hours, then I used a light bulb (8 watts) to drain them down to about 10% full. Then I charged them again. I got this idea from a fellow at Clairmont, or at least that's what I think he told me. Googling around yielded conflicting information, so I went with the Clairmont guy's recommendation.

 

There you have it...

Edited by Dennis Toeppen
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  • 1 year later...
  • 2 years later...
  • 2 years later...

I just heard back from Ritter. You're right. They've closed down. 

I keep my OBB-2's on my nightstand and I check level at least once a week. I never let them go into the red. If they become completely discharged, they are ruined. Before I kept them on my nightstand, I lost one by letting it discharge all the way. That was a costly mistake.

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I sold all my OBB-2 batteries and chargers. The money I got back nearly covered the cost of purchasing the Oppenheimer ARRI 416 Battery Adapter.

Now I can power the camera with V-Mount batteries, and thankfully, can sleep well at night.

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On 3/8/2020 at 5:25 AM, JJ Walker said:

I sold all my OBB-2 batteries and chargers. The money I got back nearly covered the cost of purchasing the Oppenheimer ARRI 416 Battery Adapter.

Now I can power the camera with V-Mount batteries, and thankfully, can sleep well at night.

Is it necessary to buy the power base/riser plate? I can't figure that out from their literature.

 

Thanks!

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On 3/10/2020 at 4:06 AM, Dennis Toeppen said:

Is it necessary to buy the power base/riser plate? I can't figure that out from their literature.

 

Thanks!

No, there is no need for any other accessories, including the Riser Power Base. (I don't think they made one for the 416.)

Only the On-Board Battery Adapter is required.

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