8mm Forum: How often should you replace belts?

This is topic How often should you replace belts? in forum 8mm Forum at 8mm Forum.

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Posted by Brad Kimball (Member # 5) on January 22, 2017, 04:23 PM:

After nearly 30 years they still look okay. Should one simply replace them anyway and in what intervals? I have 2 Chinon 7000 and a Eumig S802.

Posted by Andrew Woodcock (Member # 3260) on January 22, 2017, 05:55 PM:

No point until necessary. If a belt is good,and working entirely correctly, why change it?

This 30 yr ruling is more applicable to electrolytic capacitors than it ever is for any mechanical component that still functions 100% correctly.

Posted by Clinton Hunt (Member # 2072) on January 22, 2017, 10:02 PM:

I am the same as Andrew.I only replace the belts if I'm watching a film or switching it on after a long time of no use, and nothing turns.
Then I go to my spare belts container or if there isn't a replacement then I go to a machinery/pump place here in Matamata and get an "o" ring. [Smile]

Posted by Winbert Hutahaean (Member # 58) on January 22, 2017, 11:35 PM:

But sometimes, old belt can snap in the middle of the show. If this thing happen, this mean one-two frames will get burnt if you do not stop the light instantly.

For belt that tends to loosen you will notice the change, e.g slowing down. But for cracking belt, you can hardly notice it, and suddenly it snaps.

I just starting the topic with that very issue here: Belt is not melting or loosen, but cracking. What material is this?

You need to open your projector and see what type of symthom you have. If it is the latter, change your belt now.

cheers,

Posted by Phil Murat (Member # 5148) on January 23, 2017, 01:32 AM:

Hi Winbert,

I get Beaulieu's & Heurtier's , each of them have still their "genuine" belts and from origine, means something like 36 years old .......

however, Heurtier seems to be showing Silicon material belt (to confirm) ......

Both Beaulieu's & Heurtier"s category looks to be in excellent condition.

Only replace belts over an "on condition" status.....

Posted by Winbert Hutahaean (Member # 58) on January 23, 2017, 05:35 AM:

This is what I see, the old belt (genuine) seems to last longer. But the new made belt it is not, and I guess it is made of different material that can crack.

Posted by Andrew Woodcock (Member # 3260) on January 23, 2017, 05:40 AM:

It's also worthy of note that "the better machines" will NOT burn a single frame if the main drive belt snaps.

They have electronic detection when the main drive load reduces drastically and as soon as the motor begins to over speed, the whole unit, including the lamp circuit, shuts down immediately to protect your films until the belt is replaced.

I've had this happen to me now on two occasions and not one single frame of film is tarnished in any way.

Posted by Brian Fretwell (Member # 4302) on January 23, 2017, 11:26 AM:

Also those who have replaced tungsten lamps with LEDs (A1/17s etc) won't have to worry about burnt frames.

Posted by Osi Osgood (Member # 424) on January 23, 2017, 12:15 PM:

When they get gooey!

OSI, master of the obvious. [Smile]

Posted by Douglas Warren (Member # 1047) on January 24, 2017, 08:26 AM:

I'm with Andrew and Clinton on this: No need to change them until the day they go "snap". It's amazing how long some belts truly last!

Posted by Evan Samaras (Member # 5070) on January 24, 2017, 10:44 AM:

"If it ain't broke, don't fix it"

Posted by Andrew Woodcock (Member # 3260) on January 24, 2017, 11:49 AM:

Agreed, but do collate your data!
One day it won't always work so well!

Voltage test points, torque values,belt tension values, speed calibrations, claw penetration measurements etc etc.😊😊

Do all of this when your machine is running at its peak, it will all come in very handy one day.

It's called Centrelining or Midranging and its how professional engineers return any electro mechanical process back to how it runs best.

Posted by Brad Kimball (Member # 5) on January 24, 2017, 01:16 PM:

Thank you. I think I'll just wait it out. So far, "knock on wood", all is running okay.

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