Eprad dbl mut/70 mm

[Tim Androes]

Has anyone ever run 70mm off an Eprad dbl mut? i know some alteration would have to take place plus a whole bunch of guidance hardware. was there ever a conversion kit? will it stand up to the weight and the different center of gravity? would it need different motors?

[Mark Gulbrandsen]

Have used and owned a few of them over the years. They were originally designed for 3-strip Cinerama's 12,000 foot 35mm reels. So in theory it should be able to deal with that much weight. What I am not really sure about is how the torque characteristics might be running 70mm. Parts for them are also pretty scarce, and anything you need may have to be made locally in a shop.


Mark

[Brad Miller]

The bigger question is why? Is there not room for a second projector or a (not crappy model of) platter?

[John Eickhof]

i'm with brad on this, i agree with mark that it probably would work, but two things...a 12k size reel still would not hold an entire 70 print and the torque at the beginning may be excessive at the increased speed of 70, thus you might have to add ballast resistance to the 1500watt lightbulb on the mut...higher rpms will help keep the torque motors cooler tho...i would use an AW3...it would be safer on the film!

[Brad Miller]

Plus the very real fact that the few surviving 70mm prints are getting more scratched, worn and damaged as every month goes by...and new prints are NOT being struck to replace them. That makes any surviving 70mm print something that shouldn't be run on some sort of rigged setup or on a less-than-desirable system in general, or by operators without years of experience running 70mm.

It only takes ONE PASS to completely ruin a 70mm print.

[Gordon McLeod]

The double mut was available for 70mm from the factory. I even once used on The Imax at cinesphere I modified several swords to be forward only 70mm for several locations

[Tim Androes]

As to the why: the customer wants it. I've tried talking him out of it. I've tried talking him into using one of his AW3R platters but he doesn't want to do that if we can modify the MUT. He is older and can't load reels onto his upper feed anymore (Brad...you've been in his booth...think four projectors). He is willing to concede to three reels of 70 at a time instead of everything on on reel.

Gordon: any idea if any of the parts still exist if i have to do this? Like Mark said, could always get them manufactured locally, i suppose.

And everybody: thank you for your responses.

[Brad Miller]

Tim, Set him up a reel arm on the non-operator side of the projector bolted to the floor. Then you can setup a couple of rollers on top so the film pulls upward off of the feed reel and then down into the projector and takes up normally.

Or remove 2 of the 4 machines and then he would have tons and tons of space.

[Mark Gulbrandsen]

Set him up a reel arm on the non-operator side of the projector bolted to the floor.

Exactly! I ran 70mm in my home screening room this way for many years. It was never any trouble and you don't have to lift heavy reels way up in the air.

[Gordon McLeod]

This was a simple sword we modified with a prevost favorite 35/70centurydi9.jpg