Can the Shopsmith Bandsaw Be Quieted

[dusty]

Maybe you can't hear the noises that cause me concern? I find it hard to believe that anyone would enjoy the sounds emitted by my bandsaws.

[benush26]

Maybe you can't hear the noises that cause me concern? I find it hard to believe that anyone would enjoy the sounds emitted by my bandsaws.

You never know.... Make a recording, ship it to Seattle and ask the radio stations to play it. You may have found the sound waves of the next generation.

[Ed in Tampa]

My bandsaw makes an almost errie sound, sort of a like the background noise you usually hear as the goul manifests in a movie. Kind of a mixture of very muffled howl in a tunnel or the wind through a wind singer.

I have isolated and re isolated bearings, guides, wheel bearings, drive coupling with no solution. Just when I think I have found it, I change the part and the noise comes back.

Dusty do let me know what you find.

[JPG]

You and I are using slightly different terminology.
. . .
When you, JPG, speak of the original rear guide bearing - to which bearing do you refer.

BTW, right now I have a pair of 627ZZ bearings in the auto-track position and one each 627ZZ in each of the back up bearing positions. I have not done any extensive testing yet but I am seeing no reason why the two back up bearings need to be 10mm wide. Cutting a few curves may show me why!!

The 'lower' "backup" bearing is actually a guide/positioner for the blade as it nears the lower wheel just like the rear/upper bearing(s) with the upper wheel. So it performs a dual function.

I am measuring a 627 bearing to be 10.25 mm wide.

The 'original' upper rear guide bearing was a single bearing. I cannot say for sure the size, but SS historically would use the same bearing for all three locations so as to minimize 'different' parts.

[dusty]

There is a disconnect here.

The auto-track bearings that I received from Shopsmith are 627ZZ and they measure 7mm, 22mm, 7mm.
http://www.vxb.com/page/bearings/PROD/627ZZ20-1

The back up bearings that I have had in both bandsaws came from Shopsmith and measure 7mm, 22mm,10.25mm.
http://www.vxb.com/page/bearings/PROD/Kit12217 (not the Shopsmith Bearings)(the Shopsmith bearing is marked 827Z but that number I have not been able to cross).

[jsburger]

You and I are using slightly different terminology.
. . .
When you, JPG, speak of the original rear guide bearing - to which bearing do you refer.

BTW, right now I have a pair of 627ZZ bearings in the auto-track position and one each 627ZZ in each of the back up bearing positions. I have not done any extensive testing yet but I am seeing no reason why the two back up bearings need to be 10mm wide. Cutting a few curves may show me why!!

The 'lower' "backup" bearing is actually a guide/positioner for the blade as it nears the lower wheel just like the rear/upper bearing(s) with the upper wheel. So it performs a dual function.

I am measuring a 627 bearing to be 10.25 mm wide.

The 'original' upper rear guide bearing was a single bearing. I cannot say for sure the size, but SS historically would use the same bearing for all three locations so as to minimize 'different' parts.

This is all getting very confusing. I think this is another case of over thinking what is going on . The modern band saw has been around for well over 100 years virtually unchanged.

The auto track roller bearing as SS calls it on the left side by the blade tensioner is a dual bearing. As such the back of the blade runs in the groove between the bearings and acts as a positioner and a backup since the SS upper wheel has a back cant. This bearing keeps the blade from running off the back of the wheel. My Powermatic 14" band saw has no such bearing on the left side since it presumably does not have a canted upper wheel. The bearing width is critical because the grove between the bearings has to be precisely on the tangent of the wheels.

The upper and lower backup bearings on the right side (business side) of the blade are single bearings. Their sole purpose is to to prevent the blade from being pushed off the wheels when you apply pressure to the blade during a cut. Their width is somewhat critical in that you want the back of the blade to ride on the center of the bearing. A few thousands one way or the other probably won't make much difference. If you apply side pressure to the work piece the blade will slid back an forth across the bearing and could be the source of some noise. LDH's dual bearing upgrade will minimize this.

Someone said the upper backup bearing should not touch the back of the blade when running free. Why? If you do that when you start a cut and the blade moves back to touch the bearing it is no longer square front to back with the table. How can I cut tenons and cheeks that way? The backup bearings on my Powermatic are easily adjustable forward and back.

BTW, when I first started cutting tenons on the band saw (bought new from SS)I found that the table was way out of square with the blade front to back. I used the shims in the help kit to get it right. There is nothing in my manual about squaring front to back.

If you have cool blocks and single backup bearings when you cut, the cool blocks will not keep the blade straight and the back will slide back and forth across the face of the backup bearing (albeit a small amount) and make noise. The Carter upgrade will not allow the blade to twist. If you do the LDH double backup bearing upgrade the back on the blade is further stabilized because it is running in the grove between the two bearings.

[JPG]

This is all getting very confusing. I think this is another case of over thinking what is going on . The modern band saw has been around for well over 100 years virtually unchanged. But the SS deviates from that

The auto track roller bearing as SS calls it on the left side by the blade tensioner is a dual bearing. As such the back of the blade runs in the groove between the bearings and acts as a positioner and a backup since the SS upper wheel has a back cant. This bearing keeps the blade from running off the back of the wheel. My Powermatic 14" band saw has no such bearing on the left side since it presumably does not have a canted upper wheel. The bearing width is critical because the grove between the bearings has to be precisely on the tangent of the wheels.

Not only is the upper wheel canted, but both wheels are also beveled. The front lower bearing is indeed a guide for the blade positioning to the lower wheel.

The upper and lower backup bearings on the right side (business side) of the blade are single bearings. Their sole purpose is to to prevent the blade from being pushed off the wheels when you apply pressure to the blade during a cut. Their width is somewhat critical in that you want the back of the blade to ride on the center of the bearing. A few thousands one way or the other probably won't make much difference. If you apply side pressure to the work piece the blade will slid back an forth across the bearing and could be the source of some noise. LDH's dual bearing upgrade will minimize this.

Someone said the upper backup bearing should not touch the back of the blade when running free. Why? If you do that when you start a cut and the blade moves back to touch the bearing it is no longer square front to back with the table. How can I cut tenons and cheeks that way? The backup bearings on my Powermatic are easily adjustable forward and back. Why? Because if it contacts the back of the blade, the blade will be pushed off the lower 'guide' bearing causing mispositioning of the blade on the lower wheel.

BTW, when I first started cutting tenons on the band saw (bought new from SS)I found that the table was way out of square with the blade front to back. I used the shims in the help kit to get it right. There is nothing in my manual about squaring front to back.

That out of square is a result of all the canting and beveling. Shimming the table is the only way I know of to 'square the blade to the table'(front to rear)

If you have cool blocks and single backup bearings when you cut, the cool blocks will not keep the blade straight and the back will slide back and forth across the face of the backup bearing (albeit a small amount) and make noise. The Carter upgrade will not allow the blade to twist. If you do the LDH double backup bearing upgrade the back on the blade is further stabilized because it is running in the grove between the two bearings.

Overthinking? I think not. This is a unique animal and requires rethinking to properly understand it's idiosyncracies.

It took a long time to get to know it enough to understand it.

[reible]

I personally don't think my shopsmith bandsaw is all that noisy, but then we all have different perceptions of what we think it should sound like. The hard part is that we have no way to compare each others machines.

I have no doubt, because people have posted so, that the bandsaw can be quite noisy. The little exposure I have is from a very small number of them. I have been to demo's and taken a shopsmith class that involved bandsaws and they seem like mine. Not all that bad and none have had the squeal described.

Now my saw came to me used and I never did run it with the old bearings and original set up. My first project was to change out the bearings and do an alignment. When I did get to the point of running the machine it was fine. It has the bearing update first posted by LDH. It is aligned with a good deal of care and I have been quite pleased with it.

I have not added shims to the table so the blade has the originally designed in blade tilt. This is a compromise but I don't find it to big a deal and if I did I could always add the shims. The blade guides I use are ceramic, I do have other sets to use but I prefer these except for when I use very thin blades, then the cool blocks work best.

I normally run the bandsaw at 950 rpm on the powerpro. I do sometimes use the built in setup but a lot of times it is just faster to set it at 950. I have played a bit with listening and changing rpm to see if I could find a resonant frequency but that has not been the case in the little playing I did. It might be possible to find some rpm where there might be a sweet spot but it will be dependent on so many factors one would have to hunt for it each time you used the saw.

Most if not almost all of the noise I hear on my saw is due to the ceramic blade guides. If I back them away it is really quiet. You can hear other blade effects, a slight bend is really easy to pick out.... that might also be heard as a periodic sound like when a weld is not perfect. If the saw were so noisy as to obscure those types of sounds then I don't think I would like it very well.

Which brings me to today. I happened to have my bandsaw out and had some wood to cut up. The 1/4" blade I had on needed to be switched out to a 1/2" blade and then switched back again. This gave me the opportunity to play with a phone app that I loaded called sound meter. This will not be scientific but was interesting none the less.

Standing at the saw in what I will refer to as the operational position, that being where I would stand if using the saw, I took readings with the wide blade. Now keep in mind this is not a hard fast rule but I've found the the wider blades make more noise then thinner blades. So what did the app say? Wide blade peaked at 84 with most readings at or about 82. This level is like a busy street but not to the level where a factory machine would be at.

So when I changed to the 1/4" blade the level dropped to an average of about 76, peak was 79. This is a major change in sound level. Keep in mind that dB is a log scale so the noise level was less then half that of the wider blade. Sitting here at my computer the reading is about 34 as a reference.

Keep in mind this is just running in place and no wood was harmed in the process. Cutting sound levels are a whole other thing and I don't even want to think about all the variables that would add in. Anyway this should be something a lot of you could do if you were interested. I have a Samsung S3 which I loaded the app on. I held the phone so I could see the screen and monitor the values and again I was standing like I would be to use the saw. I think it would be interesting to see what other see.

Before I closed up for the day I got my camera out and recorded both the wide and narrow blade. I will post these on youtube in case you want to hear what they sounded like. One of the blades has a small bend in it, I can hear it very clearly, how about you? When I have them up and ready I add the links below.

Ed

[reible]

Here are the links I mentioned above.

https://youtu.be/fblBc33CXqI

https://youtu.be/YUWJRIuPqKo

Ed

[JPG]

Narrow blade is 'bent'.