Arriflex ST & S/B magazine cavity cover- 3D printed solution

[Gareth Blackstock]

So recently I acquired an Arriflex S/B with a 400ft magazine.  The only thing missing was a magazine cavity cover.  I searched a few places and they seem very hard to locate.  I made up a cover with an online 3D designer site and printed off a few until I got just the right fit.  

https://www.thingiverse.com/thing:7371415

This design is intended the fit snugly into the Arriflex ST and S/B magazine cavity when the 400ft magazine is not in use. This design features a small tongue each end to catch into the camera body cover hold-downs. Using a nail file or sandpaper will enable adjustment if the cover is too tight. As you can see from the pictures the finish looks a little rough. This can depend on the printer you use, or how you print (with supports etc) I have held a torch to the outside of the camera and no light gets past the cover. The cover clicks snugly into place and will not fall out.

I have printed the cover in brown so all its features are clear and easily seen. Printed in black material will help the cover look tidier. I originally created this cover to use on my own camera, but thought it might be handy if offered to others.

[Mark Dunn]

I'm pretty sure the real thing has a light seal- that slightly furry black foamy stuff-  on the inner edges. It's not hard to get.

Edited June 18 by Mark Dunn

[Gareth Blackstock]

Thanks for the extra info, I know of the stuff too.  Another member has kindly agreed to lend me a magazine cavity cover so I can make a very accurate copy.  I'll be able to see what type of light seal it is and how thick.

Gareth

[Mark Dunn]

Thinking about it IIRC it's flock paper rather than foam as you don't want it to add thickness. I don't know if it needs to be on both surfaces or just on the cover piece.

[ian dart]

hi

the inner side is covered in what appears to be a very fine felt covering.

it looks like the same finish in the cavity behind the lens turret.

cheers

 

[Mark Dunn]

2 hours ago, ian dart said:

hi

the inner side is covered in what appears to be a very fine felt covering.

it looks like the same finish in the cavity behind the lens turret.

cheers

 

Thanks for having a look, this is what we needed to happen!. Most of the internet stuff is foam designed to be compressed into a cavity but this isn't that.

I think this is more like it.

https://www.firstlightoptics.com/telescope-flocking-material/black-velour-telescope-flocking-material.html

or

https://www.ebay.co.uk/itm/313454135754

Velour or flock paper.

I bet there's a cabinet at Arri Munich full of the stuff.

Could be that printing the cover in black is enough, but who wants to bet a roll of film on it?

Edited June 19 by Mark Dunn

[ian dart]

i assume it is there to ensure a light tight fit across a range of cameras and to stop reflections and any light bouncing around inside

cheers

 

 

[Gareth Blackstock]

Thanks for posting the good picture, I will be researching what I can find locally.  I think velvetine might be close.  But I want to make sure no fibres escape.  Perhaps self adhesive and/or glued with PVA...   Once I get hold of an original cavity cap I can compare light security with original and my copy.  One should be arriving soon.

Thanks for the tips guys,

 

G

[Charlie Peich]

Gareth,

After looking at the cavity cover, I believe the back side of the cover was spray painted on.
On this pic of the top side, you can see the 4 rivets holding the spring on to the cavity cover.....

 

On the bottom side, If you look closely, you can see the indents of those rivets and where the spray paint settled around the rivets when the paint was drying.

So, my opinion, the black flocking was most likely spray painted on.

Charlie

[Gareth Blackstock]

Hello,

Thanks for having a close look... Ian was correct, it is sprayed on.  I am not sure I can find fluck in a can locally.... I will see how the cover that has been sent to me compares with mine, maybe I can make a print that is snug enough to not having flocking?

[Gareth Blackstock]

So I have designed my 3D printed cover from scratch, thanks to Ian for sending me a genuine cover, I was able to see what needed improving.  I did not find any such spray that could coat the cover, but as the design is free to download, a person can print off a copy and spray on what stuff they find locally.

The design I made mimics as much as possible the original design, and i believe the cover is 100% light proof.  I have attached some pictures, one black and also a white one so the cover can be seen clearly.

The cover i designed snaps into place, does not wiggle around, and using the small lever it can be removed easily.  I made the light sealing sides larger than the original so as to ensure the cover is light proof and make a nice snug fit.

Here is the link to Thingiverse for the Arriflex magazine cover: https://www.thingiverse.com/thing:7383760

I also made a lens cavity cap, the design is a nice snug fit and certainly won't fall out: https://www.thingiverse.com/thing:7330474

With 3D prints, the finished product may depend on filament used and various printer settings.  If people do not have access to a 3D printer, there are websites like airtasker where you can put a job request like print off this cover, on the site and people with 3D printers will email you with quotes.

I am confident Arriflex aficionados will find the cover effective and a cheaper option over finding a genuine cover. 🙂

 

 

[Gareth Blackstock]

This picture shows the channels that the cover uses to ensure a light proof seal

[Gareth Blackstock]