Whining sound in bobbin shaft after 150,000 stitches every day

[Michael Walker]

Anyone else have this condition before and can tell me what had to be done to correct it? My guess would be that the bobbin shaft will have to be rebuilt to replace the front roller or ball bearing. Any thougths are sincerely welcome.

Mike

[The Embroidery Authority - OLD]

Mike,
To start,... I don't know your knowledge status so forgive me for the basics.
The rotary hook (race) must be oiled with one drop of oil before every 3-4 hours of operation. At 1000 stitches per minute, give or take, this would be around every 200,000 stitches. (Not far off from your 150,000 mark.)
You must also make sure you are getting the oil into the correct spot or the oil won't do any good. Now, let's say this is not your problem. If the sound is in fact coming from somewhere other than the rotary hook, I would say you should have an experienced tech take a look at it. I have had to replace bobbin shaft bearings before, on several occations, but they were on much much older machines like the EMC series. Wait.... I take it back. I did have to replace a rear bearing on a very early Amaya. Must have been faulty from the bearing company. What can happen here is that these bearings are sealed so that oiling or greasing is not necessary. If the seal breaks (you wouldn't know this), the internal grease leaks out and then it's only a matter of time before that bearing gives out.
To replace a bearing takes not only knowledge of the machine such as hook timing but also a very good mechanical ability with the right tools.
Gook Luck.
Ed Orantes
Melco Tech & Trainer
504-258-6260

[Fabrications]

When mine started making that type of noise a few months ago, it was a matter of the silver arm that sits in the notch of the rotary hook being pushed in too far and causing the rotary hook to get too hot. The bobbin case was actually too hot to touch and was the first clue that something was wrong there. The tech pulled that arm out a bit to where it SHOULD be and the noise went away, and so did the overheating.

[Michael Walker]

Ed,

Thanks for the info but I am very sure that it is not the rotary hook. I keep very clean and properly lubricated during the course of the day. In fact I have had it apart numerous times to insure that there is not any unusual wear or interference between moving parts in the hook. The unusual thing is that with an over night rest the noise is gone again and does not reappear until late in the day. Very peculiar. Sounds like the technician needs to be here when late in the day when the noise starts up again.

Mike

[Michael Walker]

Janet,

Thanks for your experience. Fortunately the bobbin case does not appear to getting warm to the touch. I will keep an eye on it and get the tech out late in the day when the moise develops for a more critical inspection.

Mike

[The Embroidery Authority - OLD]

Mike,
Who's your tech?
Ed

[Michael Walker]

Ed,

I have only had Herman Wilson here to do any work on Amayas.

Mike

[The Embroidery Authority - OLD]

Mike Walker,
What ever happened to your whining bobbin sound???
Ed