Tobin Motors for Arri 16s / Shoulder Brace

[Paco Sweetman]

I'm selling my two Tobin Cinema Systems Motors, as I've parted ways with my Arri 16s.

 

1 x TCS - TXM-22 Crystal Sync Motor £325

 

1 x TCS TXM-23 Variable Speed Motor £225

 

Or if you want both £500

 

 

And I'm also selling the shoulder brace for the Arri 16s. It still works perfectly but is obviously as old as the hills, and some of the edges

of the padding have slightly worn away (pictured) £70

 

 

Send me a PM if you are interested.

 

 

 

 

[Alex Landherr]

Hi,

I know the OP was made some time ago and in all likelihood the Tobin TXM-22 motor is sold but I want to verify it in case someone else comes across this thread.

That leads me to ask: When was the TXM-22 motor sold?

Edited April 8 by Alex Landherr

[Paco Sweetman]

Hi Alex, everything was sold back in late 2017.

[Alex Landherr]

4 minutes ago, Paco Sweetman said:

Hi Alex, everything was sold back in late 2017.

Ok, thanks for the info. I wish these motors were easier to get.

[Sebastian Bock]

Have you seen this new crystal sync motor from Pluriboom (Kamran)? 

https://pluriboom.com/products/crystal-sync-motor-for-arri-16-cameras

 

 

[Aapo Lettinen]

Kamran has that 12v 2-speed crystal motor which is available now.

and I am working on a compact motor which uses original 8v power and takes a month or two to complete, working on it with a camera tech friend.

then somewhere closer to end of this year I will probably have a very advanced high end brushless motor design for the 16s with all bells and whistles one can possibly imagine, displays and everything.

so there is pretty good newly made crystal sync motor options available for the 16s this year. If you need something affordable the Pluriboom design seems good, and if needing more features or to use it with 8v then either one of the designs I am working on could be perfect

[Alex Landherr]

On 4/10/2025 at 10:10 PM, Sebastian Bock said:

Have you seen this new crystal sync motor from Pluriboom (Kamran)? 

https://pluriboom.com/products/crystal-sync-motor-for-arri-16-cameras

 

 

Yes I have. My one gripe about it is that the camera's own switch isn't able to start/stop the motor as it bypasses the internal power circuit.

[Alex Landherr]

On 4/10/2025 at 10:17 PM, Aapo Lettinen said:

Kamran has that 12v 2-speed crystal motor which is available now.

and I am working on a compact motor which uses original 8v power and takes a month or two to complete, working on it with a camera tech friend.

then somewhere closer to end of this year I will probably have a very advanced high end brushless motor design for the 16s with all bells and whistles one can possibly imagine, displays and everything.

so there is pretty good newly made crystal sync motor options available for the 16s this year. If you need something affordable the Pluriboom design seems good, and if needing more features or to use it with 8v then either one of the designs I am working on could be perfect

Hi and thanks for the info.

My desired specs for any crystal sync motor for my Arriflex 16ST (i.e. Arri mounts only) are these:

1. Must use the camera's own power circuit such that the start/stop switch on the film door works.
2. Must of course be crystal sync at 24 fps (not the NTSC-friendly 23.976-ish fps). If it can do other speeds at crystal sync that's a nice to have/bonus to me.
3. Must have an inching knob for film loading like almost all other motors compatible with my model.
4. Since the imagined motor uses the camera's power circuit the original power connection on the camera must be able to be utilized since my 16ST body has had no XLR power connector added to it.
5. I'm fine with 12v or 8v just that it's very clear which when it's time to get a battery pack for it.

Your motor project sounds very interesting; if your motor design meets my requirement list I would be very interested in one.

[Fabian Schreyer]

I would add shutter parking to that list. Even the old original ARRI crystal sync motor does it, so I would kind of expect that feature on a more expensive device.

[Alex Landherr]

2 hours ago, Alex Landherr said:

Hi and thanks for the info.

My desired specs for any crystal sync motor for my Arriflex 16ST (i.e. Arri mounts only) are these:

1. Must use the camera's own power circuit such that the start/stop switch on the film door works.
2. Must of course be crystal sync at 24 fps (not the NTSC-friendly 23.976-ish fps). If it can do other speeds at crystal sync that's a nice to have/bonus to me.
3. Must have an inching knob for film loading like almost all other motors compatible with my model.
4. Since the imagined motor uses the camera's power circuit the original power connection on the camera must be able to be utilized since my 16ST body has had no XLR power connector added to it.
5. I'm fine with 12v or 8v just that it's very clear which when it's time to get a battery pack for it.

Your motor project sounds very interesting; if your motor design meets my requirement list I would be very interested in one.

6. Should preferably have "shutter parking" which I understand means that the shutter always stops in a position such that once can see through the viewfinder.

[Aapo Lettinen]

shutter parking requirement depends on what kind of stuff is shot and how. Adding shutter parking to a motor has tons of cons designing wise so it is not always good to have it in a motor, especially if the motor needs to be really small or if there is strict power management requirements how the power can be routed and if the camera body itself can be modified or does it need to work unaltered with all the motor types and especially if it needs to work seamlessly with 400ft magazine motors too which can be both 8v and 12v versions and need power routing via the camera switch. 

 

[Aapo Lettinen]

On 4/12/2025 at 4:40 PM, Fabian Schreyer said:

I would add shutter parking to that list. Even the old original ARRI crystal sync motor does it, so I would kind of expect that feature on a more expensive device.

technically speaking, all the modern newly made motors are less expensive than the old crystal motors back in the day. The only reason why one can get the old ones for cheap is because they are used and decades old and someone does not need them anymore and wants to get rid of them.

I think sawing somewhere that those old arri16s crystal motors bought in the 70's -ish cost something between 5k and 10k in today's money. For one crystal motor. That is more than the entire developing budget of a newly made crystal motor made now including all the designing and testing and making multiple finished motors.

The Eclair ACL camera cost back in the day somewhere around 40k in today's money. They made a lot of them. I estimated that they probably had about half a million euros of developing money for the crystal motor system alone! then separate budget for making the devices, probably around 10k to 15k per camera to make the electronics.  I typically have had about from 1k to 2k developing money to make entire Eclair ACL crystal sync motor electronics, then couple of hundred euros per motor to get the parts and put it together and test it.

If used filmmaking equipment is cheap it does not necessarily mean it would be cheap to make a copy of it from scratch today. The Eclair ACL cameras are sold for something between 2k and 3k nowadays with working motor, but if wanting to make a new one from scratch it would still cost about 40k  today, approximately the same than 50 years ago.

 

Just wanted to explain why some corners need to be cut when designing new camera stuff, these are not obvious until one starts to make them by oneself. Today when designing a new crystal motor I would expect to sell somewhere between 3 and 9 motors total, WORLDWIDE.  back in the old days when film was widely used they could have expected to sell at least couple of hundred motors, the best models even couple of thousand pieces. It is impossible to compare a motor which costs 500usd used on ebay but was 10k back in the 70's, and my newly made motor which is made out of scratch for 1k material costs and sold at 2k with 8 of them made total. It is pretty incredible that it is possible to cut the right corners enough to still make the motor good at that low budget with 10x more features than the 10 times more expensive old motor has