8mm Forum: Elf Running speed help please. NT1

This is topic Elf Running speed help please. NT1 in forum 16mm Forum at 8mm Forum.

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Posted by Tom Photiou (Member # 130) on November 12, 2017, 07:42 AM:

Hi all,
my NT1 is all up and running and has been for a few months now. Although everything seems ok it does appear to be running very slightly slow. everything is well oiled and greased where it should be, and the belts are fitted correctly, its only slight, possibly 21fps ish, noticed on some films not others, no wow or flutter,
I recently had it stripped down due to the problem of old grease etc, cleaned it all up nice and re oiled and greased everything up.
Belts all ok, quite baffling. Any Idea's please?

BTW, The motor belt is on the correct pulley [Wink]

Posted by David Fouracre (Member # 3883) on November 12, 2017, 07:55 AM:

Check motor capacitor by substitution.
Perhaps worth a try.

David

Posted by David Guest (Member # 2791) on November 12, 2017, 01:23 PM:

yes motor cap and also cam tank

Posted by Tom Photiou (Member # 130) on November 12, 2017, 02:39 PM:

Thank you.
I know the cam tanks fine now. By motor cap is that the capacitor?

Posted by Robert Tucker (Member # 386) on November 12, 2017, 05:02 PM:

Yes that would be correct. These tend to dry out and need to be replaced as with most capacitors over time.

Posted by Tom Photiou (Member # 130) on November 14, 2017, 12:44 PM:

Thank you all, i will give this a go. [Wink]

Posted by Kevin Clark (Member # 211) on November 14, 2017, 01:00 PM:

If it is about 20% slower and running that speed constantly Tom I would personally have thought it may have a 60hz motor pulley fitted instead of the 50hz one it should have for UK use?
When the AC motor capacitors develop problems it is more likely the motor won't start at all or run weakly / uneven speeds and possibly get hot too.

If it is the motor pulley Grahame Newnham sells them for £8 each, on his list as follows:

***** Motor pulleys for Elf/Eiki projectors, 24/18fps £8 each *****
* Replaces 60Hz pulley on machines (mostly 110volt), that run slow in UK! *

Kevin

Posted by Maurice Leakey (Member # 916) on November 15, 2017, 03:32 AM:

Tom
I understand that the capacitor provides a "strike" surge to start the motor. If the capacitor is faulty it is probable that the motor will not run at all.
You say the motor belt is on the correct pulley. However, both belts must be on their correct pulleys.
For sound speed the belt must be on the large pulley from the motor, and directly opposite the small pulley on the shutter spindle.
Have you checked the plate to see if it is a 60 Hertz (Cycles) model as suggested?

Posted by Kevin Clark (Member # 211) on November 15, 2017, 04:25 AM:

Tom - If this is the extra projector you were sent as a parts machine then. knowing its source, it could very well have bits and pieces from other machines in it hence there could well be a 60hz motor with 60hz pulley fitted regardless of the plate on the back of the projector. Constant speed drops are not the usual effect of duff AC motor capacitors as I said in my post above.

Kevin.

Posted by Tom Photiou (Member # 130) on November 18, 2017, 10:14 AM:

Thank you all again for the replies,
All the pulleys are correct, the motor and capacitor are actually from my spare machine, (i bought a new capacitor and this one is now fitted to my original motor as a spare).

Here's something strange, i put Blue Thunder through last night, all was perfect, it appears that only one or two films are noticed at the slightly slower speed, is there such a thing as this, (without sounding stupid?) [Confused]

Posted by Maurice Leakey (Member # 916) on November 18, 2017, 02:42 PM:

Tom
You could check the speed by running a known length of film (in feet) against a stop watch, or a watch with a second hand.
100 feet of 16mm running at 24fps should take 2 minutes and 47 seconds.

Posted by Tom Photiou (Member # 130) on November 18, 2017, 03:32 PM:

thanks Maurice, i will try that tomorrow evening.

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