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In Jacob Anderson's "Repairing Shopsmith Mark V Headstocks" DVD he makes a statement about what he expects the noise level to be. He makes the statement in question toward the end of the DVD after having just rebuilt a Mark V 500.

Can anyone tell me what he said the anticipated dB level should be and at what speed he was running the headstock when he took the reading. If I remember correctly, he had the headstock sitting on a pad on his work bench.

I hope that he was at low speed and that he said the noise level reading should be in the low 80dB range.

This noise level (80dB) is relatively quiet. Mine, mounted on the tubes and running at SLOW speed, measures 82dB.

I don't know the db of any of mine. I have no way to measure it and don't really care anyway. But I can tell you that everyone of them (10) sounds different as it runs.
If I were using all of them regularly I'm sure that I could ID each of them by sound.
I have mechanics ears and can hear car engine problems from the next road over and can hear a dry bearing on a combine and pick it out from the scores of bearings used on it. I do have a minor problem with "some" voices.
I often say to my wife "Can you hear that noise?" and she more often than not does not.
Then again, I have very selective hearing. Just ask my wife...

dusty wrote:...This noise level (80dB) is relatively quiet. Mine, mounted on the tubes and running at SLOW speed, measures 82dB.

Back up 10 feet and measure. dBs will go down.

All I can say is my 10ERs are quieter than my Mark 5.

dusty wrote:In Jacob Anderson's "Repairing Shopsmith Mark V Headstocks" DVD he makes a statement about what he expects the noise level to be. He makes the statement in question toward the end of the DVD after having just rebuilt a Mark V 500.

Can anyone tell me what he said the anticipated dB level should be and at what speed he was running the headstock when he took the reading. If I remember correctly, he had the headstock sitting on a pad on his work bench.

I hope that he was at low speed and that he said the noise level reading should be in the low 80dB range.

This noise level (80dB) is relatively quiet. Mine, mounted on the tubes and running at SLOW speed, measures 82dB.

If anyone has the Jacob Anderson DVD and has watched it, could you tell me what he says about dB levels and at what speed he is running the headstock. I would appreciate it very much.

Slow, 80-82db, from about a foot away.

riot_nrrd wrote:Slow, 80-82db, from about a foot away.

Thank you very much for the effort and for the information. This will be very helpful for me.

I am posturing to do a rebuild and this is some of the information that I wanted to have on hand.

I have found between running the headstock during any application along with the dust collector, it is more important than ever to protect your ears, especially if you suffer from tinnitus (sp?) as I do. At least it keeps the condition from getting worse.
BPR

I've done a little work in a sound room. (but I don't claim to be an expert) The only way to get accurate readings is to place the noise source in an anecohic (without echo) room. The distance at which the reading is taken is very important as the sound level drops off as to the square of the distance. Thus, published dB readings that don't specify a distance are useless.

Sound readings are usually taken with the meter on the A scale (dBA) which more closely duplicates the human's ability to hear different frequencies. As we get older the higher frequencies become harder to hear. In the lab, many readings are taken 360 degrees around the source and then averaged. Only one reading would be pretty useless.

Since the dB scale is logarithmic, If you have two noise sources, each at 80 dBA, the combined the reading would be 83 dBA. Thus, there is a tremendous difference between 80 dBA and 90 dBA. 85 dBA is considered the threshold at which hearing loss will begin to occur if hearing protectors are not used. As the sound level goes above 85 the allowable time of exposure drops dramatically.

In our woodworking sphere of interest, almost all of the safety concerns are concentrated on tools and accessories that can cut us. The noise level of these tools has not been a serious consideration. We all have been guilty of working without hearing protection, and the simple fact is that many woodworkers today are loosing their hearing, little by little, each time they are in the shop. Giving the noise level a lot of weight in your purchasing decisions makes a lot of sense. Saving money now might mean spending dollars on hearing aids later.

8iowa wrote:I've done a little work in a sound room. (but I don't claim to be an expert) The only way to get accurate readings is to place the noise source in an anecohic (without echo) room. The distance at which the reading is taken is very important as the sound level drops off as to the square of the distance. Thus, published dB readings that don't specify a distance are useless.

Sound readings are usually taken with the meter on the A scale (dBA) which more closely duplicates the human's ability to hear different frequencies. As we get older the higher frequencies become harder to hear. In the lab, many readings are taken 360 degrees around the source and then averaged. Only one reading would be pretty useless.

Since the dB scale is logarithmic, If you have two noise sources, each at 80 dBA, the combined the reading would be 83 dBA. Thus, there is a tremendous difference between 80 dBA and 90 dBA. 85 dBA is considered the threshold at which hearing loss will begin to occur if hearing protectors are not used. As the sound level goes above 85 the allowable time of exposure drops dramatically.

In our woodworking sphere of interest, almost all of the safety concerns are concentrated on tools and accessories that can cut us. The noise level of these tools has not been a serious consideration. We all have been guilty of working without hearing protection, and the simple fact is that many woodworkers today are loosing their hearing, little by little, each time they are in the shop. Giving the noise level a lot of weight in your purchasing decisions makes a lot of sense. Saving money now might mean spending dollars on hearing aids later.

Are all of these facts relevant if all one is doing is collecting readings for comparative analysis.

If I take a reading from 5 feet away from the headstock before rebuild and I then take another reading from the same location after rebuilt and the readings are the same - I can conclude that I did nothing to reduce noise level.

Am I reading you correct, 8iowa?

I realize that the shop is an acoustic chamber and that if I take readings from different locations they are likely to be different. All that I am attempting to do (for my own curiosity) is determine if a rebuild reduces the noise level significantly or not.