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Arriflex 16 S


Michael Leake

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I just purchased an arriflex 16s from ebay, it has not arrived yet. It does not have a Magazine cavity cover . Does anyone have an extra?, How much? or where I might get on. The motor was advertized as being "seized" and would not turn.

I may be naive, but with my mechanical backround, I think I can repair it. The motor is the variable speed type reverse/forward.

Next, What would be the voltage/amp power supply to use or I can make this also. Thanks for information from everyone in advance.

Michael

 

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  • 2 weeks later...

If the motor is truly seized, it's either the bearings or it was dropped and the inching knob and/or shaft is bent. If the barrel won't turn, it was probably dropped and damaged the housing. If the motor runs but the camera doesn't it's probably the rubber coupling which tends to deform and dry rot - I have replacement kits for those. If anyone needs any parts, I have just about everything.

 

Sean

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I should read and update more often.. The motor that came with this arri16 was seized and it was the bearings. I ordered and installed new sealed bearings, cleaned all of the parts, polished contacts, applied lube conservatively and the motor now works. I actually had it powering the camera. I had issues with the eyepiece. It has water damage and rust on the glass. I used oxalic acid to dissolve the rust with absolutely NO damage to the glass lenses. It will soon will soon be back together. with light lubing(I do not have any array lubes at all) the action of the diopter seems very smooth. More updates as I progress.

Thanks to all for help

michael leake

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The deal I got on arri is this: arriflex 16mm S, NO COVER for the film compartment. An Anginieux 10-150 zoom lens(a little rough looking, but working) an arriflex 8V variable motor(Now repaired and running), the diopter/viewfinder has rust on two of the interior lenses(rust got removed). All for $415.00 Might be a bargain, not really sure. Once it is running, I will think it is a bargain

M.L.

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  • 10 months later...

I just received my 16S that I got through e-Bay. I paid $499.99 + S&H. It's all there and in what I consider very nice condition for its age. Now, I just need a lens and power supply and I'm ready to go.

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  • 4 weeks later...
  • 3 months later...
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This is to let all know that the rebuild of my arri 16 s is done! It runs beautifully. I will now build a power pack and soon film. I had to rebuild the switch assembly and it seems that the buckle switch does not work. It could be an adjustment or it might have to be wired again. I am not sure. The variable speed motor which I rebuilt is working great!. Later.

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  • 2 weeks later...
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Arriflex 16s: does anyone know how many rpm's on a variable or fixed speed arri motor are needed to get 24fps?

thanks to anyone.

M.L.

I made a 12v power pack for my arri 16,(it powers the camera with film in it.) however I have to put a resistor

or potentiometer in the circuit to step down to 8v.

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Greetings Michael!

 

I’m curious as to why you are concerned about the rpm’s of the Arri 16 Variable Speed Motor.

 

I've never seen rpm figures for the 'Wild' motor printed in Arri literature. There were rpm figures listed for the 24fps sync motor however, but that had to do with differences between 50Hz and 60Hz, and 24 or 25fps.

 

This 8 volt 'Wild' motor was the 1st motor Arri offered for the 16S when the camera was introduced in 1951. (The history lesson of this post)

 

This is a pic of the 1st generation 16S with the wild motor. Notice, there was no opening for an external magazine. Just 50 or 100ft rolls.

 

300zcbt.jpg

 

This is the finder side......

 

8wxgmp.jpg

 

 

The wild motor design didn't change much until Arri changed the voltage requirements from 8 volts to 12volts in, or around, 1980.

 

The math to figure out the rpm's is fairly simple, in my opinion, but if I'm wrong, someone please correct me.

 

The drive shaft where the motor fits into .....

 

10mvf4l.jpg

 

has to rotate 3 times to achieve 1 exposure. This includes the shutter rotating, the un-exposed film pulled into place, the registration pin to register the film, the shutter to open and expose and then close.

 

You can easily check this by lining up the mirror from the front to cover the aperture, then rotate the drive shaft 3 times. It should stop in the same 'position' as you had placed the shutter originally. You could rotate the shaft with your finger on the coupling, or you can have your wild motor in place, make some marks on the inching knob and motor housing to give you a reference point, then count the turns on the inching knob.

 

If it takes 3 turns of the camera's drive shaft to expose 1 frame of film, then 24 frames would take 72 turns or revolutions of the motor's drive shaft. You want to run your camera at 24 frames per second, then your wild motor would be running at 72 revolutions per second. 60 seconds in a minute would give you (60 x 72) 4320 revolutions per minute, or 4320 rpm.

 

From a 1970 instruction manual...

 

hsq72f.jpg

 

hvxjbo.jpg

 

However, your wild motor will handle 12 volts, in fact, Arri said that in a 1972 product brochure....

 

4jn6vb.jpg

 

The wild motors on the 16S are designed to be run at 8 volts. They'll work at 12 volts, but the higher voltage damages the brushes of the motor and it will shorten the motor life.If running with 12 volts, don't use the 400ft mags and 8 volt torque motors. Those small motors are designed for 6 -8 volts, given 12 volts they will run too fast and strip the film when 12 volts is applied.. So the 12 volts has to dropped down to 8 volts. Easily done.

 

Arri says the wild motor runs from 6 - 40 fps. Well, I've run mine from 4 - 50 fps off of a 8 volt battery, without a 400ft magazine and torque motor. It depends on the condition of the battery.

 

Finally, I can see how you came up with the 2100 rpm figure. The 16S is not the same as a camera with a 180 degree half moon shutter where half the 360 degree shutter disc is black and the other half open, but it has a 'Bow-tie' shutter. It consists of two open segments (90 degrees each) positioned opposite of each other.

 

A bad pic of a Bow-tie shutter...

 

2dhzcsi.jpg

 

 

 

 

Butterfly shutters rotate at half the speed of a half-moon shutter. As explained by fellow forum member, and knowledgable of all things 16S, Tim Carroll:

 

"Okay, I am not sure what folks are referring to as butterfly shutters, but if you are really meaning bow-tie shutters, then the Arriflex 16SR does not qualify. The Arriflex 16S, 16S/B, 16St, and 16M all have bow-tie shutters. On the Arriflex, a bow-tie shutter doesn't expose the negative twice, it rotates at half the speed of the movement. The mirror does a complete revolution every two frames."

 

and by forum member Jonathan Benny:

 

"The disk with two 90 degree openings is turning at half the speed of what a shutter with a 180 degree opening would, therefore the same shutterspeed. Each frame is only exposed once and the film is advanced between each 90 degree opening."

 

Sam Wells:

 

"Arri S and 16BL segment the mirror itself with a small stripe so you see your "48 flicks" so to speak in the viewfinder but this has no effect on how the film is exposed when the shutter is open."

 

The 90 degree opening is moving half the speed, therefore it's exposure is the same, or equivalent to a 180 degree shutter.

 

 

​There you go, something to think about. lol.

 

Regards,

Charlie.

 

 

 

 

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Charlie, Thanks. This information is exactly what I needed. As to why? Mostly curiosity, and I was considering the possibility of constructing a variable speed motor with precise speed setting. Yes I should just try and get a Tobin motor, however that is not

in my budget at this time. I also like the tinkering. I do have two possibly serviceable power belts. They are in need of re-celling and

I am working on that. I have the Arri 16 working (cleaned, lubricated and back together) and will be making a short demo test film to see how the rebuild actually went. This will probably take some time. I have to test some telecine techniques first. I did build a temporary power supply with supplies and parts from ebay. I has 8, 1.5 D batteries and I have a variable potentiometer in the circuit to step it down from 12v, to 8v. We will see.

Thanks for all the information again.

Mike Leake

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  • 2 months later...
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Charlie Peich

In a post on Cinematography.com, dated Jan 07, 2017, near the end of an article when you commented about arri wild motors, I found the below reference: this



Sam Wells:


"Arri S and 16BL segment the mirror itself with a small stripe so you see your "48 flicks" so to speak in the viewfinder but this has no effect on how the film is exposed when the shutter is open."

this answers my question!






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  • 3 weeks later...

I've got my 16S working. Got the obligatory Schneider 16mm lens, matte box, 400' mag, torque motor, and the angle finder. I also bought some of those ARRI battery packs that were on e-Bay and re-celled each with two 4 volt batteries connected in series. I purchased the charger that accompanies those battery packs and am going to install a 3055 voltage regulator (and varriable resistor) in line with the output so I can re-cahrge the battery packs. Currently, I purchased a "Deltran" 8 volt battery tender that I'm using to keep a charge on them. I've also fabricated some adaptive power cords with the XLR connectors that connect to the battery pack and into a box that I can mount onto my tripod. I took the battery tender apart and re-built it so that it'd fit into the box. Ones side is XLR and the output are the two BNA connectors so my power cord from the 16S will plug in to it. If ya want, I'll post some pictures.

Edited by Mark Day
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