What does your spindle sound like?


I had an issue and started a ticket with Langmuir and am impatiently waiting on the response.

I believe I might have bearing issues but I am not sure just how loud or what a normal machine sound like after about 5 hours of total cut time /light wear. I performed the break-in as described in the assembly guide and have only done about 1 30-40 minute job per day on aluminum and all chip loads far under suggested and usually give it a warmup at the 5000 RPM toggle for about 10 minutes before starting. Now I cant know if I was really lucky or just the normal break-in of the bearings was unusually quiet during the first times I have been using it but I had an incident where the motor stalled out I am assuming because it overheated after a 27 minute job with a .25 4 flute endmill with .001 chip load passes. It was running fine and the spindle just cut out and the XY kept going but I acted quick and hit pause the coolant kept running on the bit but the spindle only tried to restart briefly once after pausing and then just wasn’t turning on anymore so then toggled it off on cut control and went to grab a thermal camera. Everything was at about 157F from what it could scan with the cover on. I took it off and did not see any higher than that anywhere. Now my machine sounds louder than before or higher pitched even after a day cooling?! https://photos.app.goo.gl/JzJoYyjz4VPS6dSs8 I was having trouble in the wait for their tech support so I took this video and then dug the forum and I saw how people had removed the motor and so I began to look for the tensioning features . I first stuck a screwdriver in the slot on the side of the belt cavity and was able to deflect the belt by about a quarter inch with very low pressure. So I tried to loosen the bolts and pull tension on it and try again. I achieved very taught belt / hard to deflect from the side and it still made the same noise as the video I linked. Then removed the motor and spun it freely and it felt relatively smooth like a motor should but noticed the belt had frays (https://photos.app.goo.gl/xNEehLAeKPBLwAAe6) and that the pulley on the motor had these weird small foldovers at the top of the pulley sticking into where the belt area would be? see here https://photos.app.goo.gl/2FCaAJB5R9jo62m1A
Also I observed that there is almost a clicky feel to the spindle assembly. What is it supposed to feel like?

I also made a folder so the photos and videos are all here https://photos.app.goo.gl/7ZTqidzCwX4EZqDm6.

Any help would be appreciated in calming me down while i wait lol I gotta finish parts by hand now the engineers are breathing down my neck for their prototypes!



It looks like your motor pulley wasn’t well deburred and has sharp edges. To me this looks like a warranty issue (hopefully they’d send you new pulleys and belt), but I think you could fix it in the meantime by deburring those sharp edges and replacing the belt.

The spindle bearings should turn smoothly, the bearings sound a little rough to me in that last video.

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I have been looking all over for the belts online and they look like they might be a custom gates belt for Langmuir its not available on Gates website or any suppliers anywhere from what I could find.

Jake from Langmuir responded to me last night on my ticket but haven’t heard what he thinks about the videos or pictures yet.

did you ever get this figured out? My machine suddenly started making the same noise as yours.

It was 100% the bearing spindle assembly making the noise. They shipped a new one and it sounded completely different than the first one they sent right from the start of the break in program did. I also placed what seemed like an overly large amount of tension on the belt when the new assembly went on using a hammer handle as a lever but it runs really well and silent and i installed 2 thermocouples one on the motor and 1 on that bearing block with thermal conductive epoxy and ive never seen it get above 110f on the spindle and 150 tops on the top of the motor. That was my max temps at 8 hours of running programs straight at ~7000 RPM in aluminum with a 1/2 endmill at .001 chipload making 48 of these 1 inch deep slots from 4 to 9 inches long see below.

Im really happy with the noise level of this machine running i occasionally put the wrong speed feed on drilling and that lets some squeaks out but this thing is often less noticeable than my belching co workers. Comparable to a windowshaker air conditioner if youve got your feed speeds set conservatively. So on that note if your machine is high pitch when just free running check belt tension then if that doesnt help take the motor off and feel the bearings if they feel clicky they should be smooth. I cant know how long you have had your machine but get ahold of the support via the main site maybe you had an assembly from the timeframe where they had manufacturers send them spindles out of tolerance and they can help get things back to the happy path. Good Luck and may your machine find its bearings again real soon!