8mm Forum: Magnon 800 takeup spool tension

This is topic Magnon 800 takeup spool tension in forum 8mm Forum at 8mm Forum.

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Posted by Ron Blombery (Member # 2959) on February 18, 2012, 09:37 PM:

I have a Magnon Instdual 800 projector. There is a lack of tension in the takeup spool, so that if I use an auto-loading 400ft spool, the film does not wrap evenly around the centre area but grabs near the edge of the spool, forming a large uneven loop.

I have worked out which of the spring belts needs to be shortened to increase the tension, but the question is: by how much? I can do it by trial and error, but is there some standard or measurement for takeup spool tension that I can refer to to get it right?

Thanks in advance for your help

Ron

Posted by frank arnstein (Member # 330) on February 19, 2012, 07:19 PM:

Hi Ron,

Try using another take up reel as yours sounds like its faulty.

dogtor frankarnstein [Wink]

Posted by Ron Blombery (Member # 2959) on February 19, 2012, 08:24 PM:

OK, so what would be the width between faces for a good 8/Super 8 takeup spool?

And how much should the "fingers" (sorry if that's not the right term, but I'm new to this)that grab the film for auto-loading protrude into the area?

Posted by frank arnstein (Member # 330) on February 21, 2012, 03:58 AM:

Hi Ron,

8.9mm is the inside width measurement I found on a known good 400' auto-reel. The gap between the pickup fingers will be less than 8mm but I can't measure that. They should be sprung inwards to enable grabbing of the 8mm film as it slides over them.

However, consistancy and eveness of the reel gap is most important. So if its been sitting on one edge for a while it will soon become buckled and cause the problem you are having.
Hot water will sometimes assist in straightening them out but try using another reel if you have one.

dogtor frankarnstein [Razz]

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