Damping Vibration

[Byron Trantham]

My daughter just bought a commercial embroidery machine. Weights a ton comes with a stand and wheels. The wheels can be defeated. She's using it on the second floor of her house. She says the thing vibrates the floor! Anyone know of some "dense foam?" that might help dampen the mechanical vibration? Or perhaps some other idea. She will appreciate anything you guys might come up with. So will I.

[Donnie Raines]

Any way of really knowing what causes the vibration?...is it "normal" for it to do this??. I was thinking some sort of extra weight may help, but you said this thing is so heavy to begin with. I wonder if there is some type of belt drive???...

..I guess a nut and bolt through the ceilling is out of the question....

[Byron Trantham]

Any way of really knowing what causes the vibration?...is it "normal" for it to do this??. I was thinking some sort of extra weight may help, but you said this thing is so heavy to begin with. I wonder if there is some type of belt drive???...

..I guess a nut and bolt through the ceilling is out of the question....

It's a sewing machine, a powerful one. I guess just the action of the needle(s) - it runs up to six theads at once - is causing the vibration which I presume is normal. Lots of vertical movement.

[Ken Garlock]

Byron, I have bought two different types of vibration mounts from McMaster & Carr. They have a large selection, just do a search on "vibration mount". Something that might be of interest is the vibration damping pads of page 1224. Good luck.....

[Byron Trantham]

Byron, I have bought two different types of vibration mounts from McMaster & Carr. They have a large selection, just do a search on "vibration mount". Something that might be of interest is the vibration damping pads of page 1224. Good luck.....

Ken, you da man. I think this is just what she needs. She'll let us know.

Thanks!

[Ken Robb]

Byron,

My normal job is a Sales Engineer in the Vibration isolation industry. If it is a typical 1 head six needle embroidery machine, it is probably running at 1200 stitches/ min. This means the needle head is going up & down 1200 times a minute. Depending on the type of embroidery pattern it may be as slow as 800 stitches per minute. The noise is mainly an impact type. I would estimate the forcing frequency to be in the range of 20-30Hz. You will need a fairly soft elastomeric pad to accomplish any isolation as the ratio of forcing freq/natural freq of the isolator must be greater than 1.44 ( which is the sq root of 2). Most of the pads out there are for 40 PSI loads or greater. Therefore a 4" sq pad would carry a load of 640 Pounds(16" x 40PSI). This is too stiff to provide much isolation. Use a circle cutter to cut 5 or 6 1" holes to reduce the load capacity of the pad. Also, since the machine is on the second floor you will lose some isolation efficiency due to floor deflection. From a design engineering standpoint your foundation (ie floor) should be 10x as stiff as the isolator. Most second floors are not.

[Byron Trantham]

Byron,

My normal job is a Sales Engineer in the Vibration isolation industry. If it is a typical 1 head six needle embroidery machine, it is probably running at 1200 stitches/ min. This means the needle head is going up & down 1200 times a minute. Depending on the type of embroidery pattern it may be as slow as 800 stitches per minute. The noise is mainly an impact type. I would estimate the forcing frequency to be in the range of 20-30Hz. You will need a fairly soft elastomeric pad to accomplish any isolation as the ratio of forcing freq/natural freq of the isolator must be greater than 1.44 ( which is the sq root of 2). Most of the pads out there are for 40 PSI loads or greater. Therefore a 4" sq pad would carry a load of 640 Pounds(16" x 40PSI). This is too stiff to provide much isolation. Use a circle cutter to cut 5 or 6 1" holes to reduce the load capacity of the pad. Also, since the machine is on the second floor you will lose some isolation efficiency due to floor deflection. From a design engineering standpoint your foundation (ie floor) should be 10x as stiff as the isolator. Most second floors are not.

Ken, I was looking at these as a vibration isolator. They are from McMasterCarr....

These firm, durable pads are constructed of PVC for chemical resistance and reinforced with fiber for durability ( 5/8" thick pads also contain cork for increased deflection and to help deaden sound). Pads have a cross pattern on the top and bottom to help secure machinery to the floor. Temperature range is 32° to 158° F. Color is green.

Pad packs contain four 1/4" thick top pads and four 5/8" thick bottom pads that are ready to install.

Pad Packs
Max. Deflection
Pad Size, Load, @ Max.
Lg. x Wd. psi Load Durometer Per Pkg.

2" x 2" 93 0.054" 80A 60105K61 $6.16

3" x 3" 55 0.047" 80A 60105K62 13.80

What do you think?

[Ken Robb]

Byron,

I think these pads are still too stiff. Try these instead 60105K61 (load of 144#)or these 5981K66(load of 496#) with some holes in them. They are on page 1225.

Ken

[Byron Trantham]

Byron,

I think these pads are still too stiff. Try these instead 60105K61 (load of 144#)or these 5981K66(load of 496#) with some holes in them. They are on page 1225.

Ken

I will send this to my daughter right away. Thanks so much for what we considered almost unobtainable information.

[Keith Starosta]

I will send this to my daughter right away. Thanks so much for what we considered almost unobtainable information.

In the year and a half since I registered at this wonderful site, I've come to find that there are very few pieces of unobtainable information to be had out there. You guys are great!!

I hope you get it worked out, Byron!!

Keith