Jump to content

new ALCS compact crystal motor for Eclair NPR


Aapo Lettinen

Recommended Posts

  • Premium Member

I probably mentioned somewhere that I am working on a NPR crystal motor project which would be completed later this year if there is at least 3 orders so that I can get my own money back from the machining and parts costs and R&D work.

I have narrowed down the specs of the new motor enough that wanted to post a new thread for it. As with my other current projects, I am making the development work in steps and advancing to a new steps necessitates that the orders come in time and pre payments are made as planned to finance my development work.

The basics:

- a completely new crystal motor for the Eclair NPR. not a modification of existing motor, I am making this out of scratch

- possible to make if there is at least 3 pre paid orders to finance the materials and research. I can't use my own savings on this project right now because need every penny for move in the Summer

- the motor has internal crystal speeds of at least 24fps and 25fps, user switchable. There may be additional speeds if there is room for the larger electronics and extra selectors additional speeds would need. prepare only for the two speeds because the main goal is to make the motor AS COMPACT AS POSSIBLE for handheld etc. use and every extra bell and whistle makes it larger and more cumbersome which is why I try to avoid adding any unnecessary extra features

- will be smaller sized than the Alcan motor. the exact size will be determined in Summer when making 3d printing tests of the body of the motor

- price is 1200usd + shipping. I won't try to make it cheaper if there is extra headroom, will try to instead make it better if there is extra budget left. it is affordable as a new motor already and cheaper does not make sense for products which are meant to last for years and years of use

- Availability: needs to be ordered and paid for in March2024 or absolutely latest before April 20. The final motors will be delivered in late Autumn, likely in October or November. Prototype available to look at after the Summer. You will get a good working motor which has the promised specs or more and which looks as nice as was possible to make with the budget, it just takes lots of time and budget to finesse the exact outer shape of the body so this is why there is no photos or renders yet.

- body will be either 3d printed or machined from solid aluminium depending on how many orders there is. I will make it as good as possible with the available budget. if there is minimal amount of orders then a sturdy print should be fine and on the other hand would be much lighter than aluminium body

- integrated tripod mounting threads, does not need separate boot/support structure. the main use for this motor is handheld etc. use where the small weight and size has best benefits but tripod use of course possible as well

- either 24v operating voltage OR 12v if I can arrange custom bldc motor drives made and there is enought orders and the 12v drives don't make the motor considerably larger and heavier.

- no shutter parking because it would make the motor much larger, heavier and more expensive. the NPR has a manual inching integrated and the goal of the project is to make the smallest and lightest motor possible for it which contradicts with shutter parking systems

Edited by Aapo Lettinen
Link to comment
Share on other sites

  • 3 weeks later...
  • Premium Member

VERY EARLY TEST PRINT OF MY 2-SPEED NPR COMPACT CRYSTAL MOTOR DESIGN. Normally I don't post photos of the earliest drafting but I will need to collect the orders for this motor beforehand so some kind of reference image is mandatory.
The motor will be approximately this sized, so noticeably smaller than the Alcan motor and considerably lighter weight. Additionally I will try to position the electronics so that the motor would be as ergonomic as possible to operate on shoulder so I will try to make it as short as possible which helps tripod operating as well, and position the electronics so that they are out of the way when the camera is on the shoulder.
SO things will change, this is just a first draft which I use in the design process. The design will be refined when I get more budget (orders) to continue with the tests and order more parts for prototyping 🙂
The price of the compact 2-speed motor will be around 1200usd + shipping and it has crystal 24 and 25fps. Will be either 24v or 12v depending on which option keeps the smallest form factor, likely the 24v is better choice but we will see.
I will need at least 3 orders before can make this into a final product. For the schedule to work out the orders need to be placed before May2024 so that it is possible to get the working prototype finished during the Summer and the final motors delivered in November.
Again, the reference photos are just the first very rough 3d print test which I use to test out the motor size and shape. The final device will be properly finished and at least partially machined from aluminium to last in use

 

20240315_214535.jpg

20240315_214723.jpg

20240315_214742.jpg

20240315_214752.jpg

Link to comment
Share on other sites

Aapo, 

Wow.. that does look a lot more compact any other option available. I hope it ends up being 12v but if not, oh well.. do you have any orders in so far? If it's going to make it easier, I do not need the 25fps option, just crsytal 24fps.. Could you let me posted if you have 2 more so I can place the order too? Also, is it possible to have d-tap and fischer plugs on the body as well? Thank you.

Link to comment
Share on other sites

This looks fantastic! I'd certainly be interested in something as compact as this! Like Giray said, what power source is this going to take? 4 pin XLR, or something like d-tap? Making a power solution for older motors was always a pain.

Link to comment
Share on other sites

  • Premium Member
4 hours ago, Giray Izcan said:

Aapo, 

Wow.. that does look a lot more compact any other option available. I hope it ends up being 12v but if not, oh well.. do you have any orders in so far? If it's going to make it easier, I do not need the 25fps option, just crsytal 24fps.. Could you let me posted if you have 2 more so I can place the order too? Also, is it possible to have d-tap and fischer plugs on the body as well? Thank you.

I agreed to trade some NPR gear for one motor if there is other orders so one order so far but still need more to fund the project.

The issue with 12v is that it needs double the amperage rating from the bldc controller and higher rating controller is physically larger (the small sized controllers are a little less than 3A which is fine for the motor at 24v but goes way over at 12v for similar wattage motor and thus larger controller needs to be used) which means less compact end result. A 12v motor drive itself can be larger as well but not as big difference as the controller size difference. So likely it would be 24v but I will test the 12v approach too if I can make it compact enough to be viable.

24 + 25fps vs only 24 fps is very little difference in size, basically few dozen cubic millimeters as only one small switch or internal jumper is needed and nothing else.

for power connector, I am intending on adding only one connector if possible and the smallest affordable one which is locking and relatively reliable. it allows user making extra cables more easily but the main reason is that I need to use the kind of connector which takes very little internal space from the electronics box to keep the whole motor still compact. Something like a XLR connector takes almost one third of the space inside the current size electronics box which makes it very difficult to fit the necessary control electronics there and would lead to needing to make the whole motor larger.

So likely I will use either a Lemo connector (expensive to buy though which is not good for the end user) or just use the same gx12 connectors than on my other devices... they are not the absolute best but they cost next to nothing and I can include spare ones for them costing 1usd instead of 100 a piece 😄

Link to comment
Share on other sites

Aapo,

I would pay the extra and get the Lemo connection.. Have you ever seen  HAfflex motors with flat bottom that resembles SRs in a way.. How about that kind of design to accommodate needed extra real estate for additional plugs, footage counter and a lemon or 4 pin XLR? If the motor connected to the body at an angle and extended back towards the magazine flat, I would be OK with it. Of course, I don't know if that's doable.

Link to comment
Share on other sites

  • Premium Member
Posted (edited)
3 hours ago, Giray Izcan said:

Aapo,

I would pay the extra and get the Lemo connection.. Have you ever seen  HAfflex motors with flat bottom that resembles SRs in a way.. How about that kind of design to accommodate needed extra real estate for additional plugs, footage counter and a lemon or 4 pin XLR? If the motor connected to the body at an angle and extended back towards the magazine flat, I would be OK with it. Of course, I don't know if that's doable.

The same connector needs to be used for start-stop connections to avoid adding multiple connectors. XLR is possible if people want to run the switch from the unused pins 2 and 3, non-standard but should be ok. Huge sized connector however.

making a separate "box" on the side just for the connectors would be doable but makes the motor pretty weird looking... if not making it ergonomically worse then might not matter. Using 200usd on connectors per motor is not possible budget-wise (I need about 70% of the budget on getting the outer body of the motor designed and finished perfectly, thus need to use more standard stuff on the motor drive and control electronics and connectors), maybe can find out something more affordable to replace Lemo with about similar form factor. That would be made somewhere between July and August because I would need to secure connectors for the whole motor batch which needs the full budget to be available.

The connector pinout would not be standard anyway so a separate cable would need to be made to use the motor, just plugging in a Arri cable would not work.

Extension towards magazine is possible but I need to test with printing how the motor would behave ergonomically and that any extension would not be on the way of the mounting latches etc. Additionally the current plan is to make the motor body out of combination of machined aluminium and 3d printed ABS plastic so will need to design the shape so that the body still stays rigid to support the camera in handheld and tripod use and is possible to machine in the first place 🙂

But yes, can arrange 4-pin or 5-pin XLR or similar style of "secure" connector which is more sturdy than the gx12 connectors I use on my other designs. Likely can't use Lemo for the high price of those connectors but the xlr should be possible to fit somewhere without making it too cumbersome, it would just be larger towards the right side of the camera with the xlr cable attached.

Displays and footage counters add quite a lot of more work, need lots of space and compromise the electronics and the outer shape of the motor so I will need to leave them out of the design for them making the motor less compact and more expensive

 

Edited by Aapo Lettinen
Link to comment
Share on other sites

  • Premium Member

More 3d printing tests. I was asked to try to include a basic footage counter and make a flat base which fills the whole area between the motor and the magazine. JUST A FIRST TEST TO FIGURE OUT THE APPROXIMATE LOOK OF THIS KIND OF SYSTEM. Not in scale compared to the camera but you can see how it would approximately differ from the first design. If making the motor this style shaped, the extra piece would  likely be a little smaller towards the magazine, this first test is likely exxagerated a little.

The extra part allows attaching more connectors (likely d-tap or two at least) and the 3-digit footage counter which allows choosing additional crystal speeds too. With the counter the motor would be more expensive, I estimated about 1800usd + shipping . The benefits are more crystal speeds (likely 9 selectable speeds during startup), a footage counter which counts to 999ft, extra connectors and a much larger flat base which allows the camera to stay upright on table/other flat surface without additional support.

These are just first tests and things will change when I get funding (paid orders) and have made more test in Summer with more refined motor body design which could be attached to the camera. The plan is to run some tests in Summer with the motor drive itself, likely finish the mounting plate first, and then build the rest of the body around that motor drive + mounting plate design.

Please let me know by DM if you are interested in this motor, either the basic 24+25fps model or the footage counter + multi speed model. I will need the orders in April to be able to continue with the planned schedule and be able to order the parts for tests (the parts for tests alone cost almost 1.5k which is why I need to have the motors paid for beforehand to be able to finish the project)

 

 

20240323_135234.jpg

20240323_135230.jpg

20240323_135224.jpg

20240323_135155.jpg

20240323_135142.jpg

20240323_135136.jpg

20240323_135125.jpg

Link to comment
Share on other sites

  • Premium Member

MORE DRAFTING.

will print this test later when having time. Here the extra housing for the display+extra speeds unit is integrated to the basic motor and I would just leave it empty if the basic version is ordered. I will very likely make it just like this so that the motor would be most versatile. The height of the motor is still the same so it is pretty compact. I drafted the one button for display functions and other button for start+stop.

This is a bit closer to the final design but still will change a lot so consider it as a first test type of thing 🙂

The extra support parts would be attached to the backside of this base unit whenever needed.

Screenshot 2024-03-28 at 23.48.55.png

Screenshot 2024-03-28 at 23.48.23.png

Screenshot 2024-03-28 at 23.47.49.png

Link to comment
Share on other sites

  • 2 weeks later...
  • Premium Member

here is the previous draft printed to test its size with the NPR camera body. This is just drafting and the final device will look different. The final will probably be just a little bit smaller in vertical direction and extending more towards the magazine to get larger mounting area on the bottom. But here you can get some kind of view what size of a motor we are talking about 🙂

I will need to wait now to collect orders (budget) to move this project forward, it only makes sense to continue the designing process if there is enough support to finish the project in the first place. So let me know ASAP if you are interested in ordering the new "compact NPR motor", I would like to work on it in Summer if in any way possible but will need the orders in April to keep that schedule because continuing requires ordering the most expensive components next before anything else can be made.

price for 2-speed model is 1200usd + shipping and for the display version with at least 10 speeds and a film counter will be 1800usd + shipping.

20240407_164638.jpg

20240407_164630.jpg

20240407_164624.jpg

Link to comment
Share on other sites

  • Premium Member
4 hours ago, Gregg MacPherson said:

Really interesting work Aapo.  How is shoulder mounting with the common view finders? There must be more space to include a shaped shoulder pad.

I will likely change the motor shape a little when getting enough budget to continue working on it. it depends on what type of bldc motor drive I can get to work with it, some of them are flatter than others which allows reducing the motor height and shaping it differently. Unfortunately these motor drives are very expensive and I can't afford making the tests without the orders in place so have to wait and see how it goes.

the camera's own gearbox is relatively large as seen on the reference images, that makes it impossible to get the motor tripod mounting area to the save level with the magazine bottom surface. So likely I will make the motor so that the motor has relatively large flat bottom with tripod threads and the back part of this area is somehow curved to shape it better for shoulder use and extends backwards enough to allow the camera sitting on table on its own balanced without tilting forward/backward.

it is relatively complex shape to model and thus I will need the final dimensions before starting making it. which like mentioned requires the budget first because I need to fit the electronics inside before knowing the exact dimensions of the motor especially vertically

Link to comment
Share on other sites

  • Premium Member

I assume most people would use a rolled towel on the shoulder and use the camera without separate shoulder pad. Because likely in any case the camera would sit too high if using a base plate with rods, then some riser, then some separate shoulder pad... the new motor will be very small but the camera body itself is still relatively high so I don't think it could be compensated enough. but could be wrong too, my test camera is not in working condition so have not tested it 🙂

in any case I will try to reduce the motor height as much as possible because it was the main goal of the motor project in the first place. modern motor drives are possible to get in flat shapes which was not possible in the past

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...