Mechanically Measure Vibration Noise: How to improve band saw cutting

[@alanmuther]

Great video as always.

[@aguycalledlucas]

Don, that’s impressive. Frankenstein saw is even more Frankensteinish now. Nice work!!

[@donsengine3158]

Ya, its getting a little over the top now. But hey, I got a much nicer to use saw out of the deal. Thanks for watching. Don

[@oddshot60]

Back in the old days before we had hertz, as a mechanic, I would listen for vibration by placing the tip of a screw driver against where I wanted to check, and my ear against the screwdriver handle to hear the vibe. Eventually, I got a medical stethoscope. It worked great.

[@donsengine3158]

Yup, been there.... 👍

[@PaulLemelin]

I don't know if this method of measuring vibration is common but I still think it's ingenious and makes perfect sense

[@donsengine3158]

What surprised me was how close I actually got to the accelerometer. I expected that the dial indicator would only be able to keep up so much and with a lot more bounce. The naked eye can only process so much so the expectation is that what you see is the actual --- but when its slowed down it becomes very apparent that you can't see and judge what's really happening. I guess this is why magicians say the hand is quicker than the eye, cause it really is. Thanks for following Paul.. Don

[@brucewilliams6292]

Hi Don, I used a sound frequency app on my phone to get the frequencies now I have a way to get the amplitude. Very impressive results. Thank you for all the great ideas.

[@donsengine3158]

Thanks Bruce I'm glad that translated into something you can use. If you haven't noticed I get little fussy about "knowing" Don

[@oddshot60]

This is very interesting. Your comparison to the action of a harmonic balancer is a good one. I hope you don't mind ... I have questions. BTW ... I do NOT ask questions to show-off or to be snarky. I own a Reliant 14inch 4 speed which is a copy of the Delta. 1. If mass is so important to a smooth cut ... why do those small, light portable band-saws seem to cut so well ... or is that hype? I do not own one, but a number of folks on YT own them. 2. Did you think to check the vibe closer to the edge of the table? Isn't there a chance that distance may increase amplitude? 3. Do you think gluing blocks of mass in the cavities along the neck of the band saw (that you braced up) could also eliminate/soak up vibe? 4. I would like to have seen you do a before/after cut on a piece of steel to show the result. Maybe this is something you could do after each step. Just so you know that somebody is listening, I am finishing up a cross-slide eliminator exactly like yours. I should be making first cuts using it on my 70 year old Atlas/Craftsman 12 inch tomorrow.

[@donsengine3158]

I guess there must be a word count limit to reply's. I wrote a book of an answer to your questions last night and now see that its missing. So lets try the synopsis version. 1. Mass in larger saws, in particular straight run blade saws is important because of the the leveraged ability to flex. Portable saws are very compact, rigid and use an off center position for the blade travel like a horizontal saw. Nearly impossible to induce flex and with near direct drive motors, just don't have the issues a larger saw will encounter. Think 68 Impala, big motor, large frame, separate body. vs Renault 5 - small high speed motor transaxle and unibody. Each one has its place. The portable saws were originally meant for plumbers to take care of pipes on the jobsite but found a lot of other uses. Great little tools, but Ide hate to have just that for my primary cutter. Saws are the big lifters in a machine shop. They get you close, your machine tools get you accurate. 2. Yes, and it was a little higher, but it was just added footage to the video and I need to keep my time limited as too many viewers just want the jist of it. The main issue is freq/vib up through the table mounts which are in the middle of the table, so I wanted to concentrate my efforts at that point. I went way too long on this yesterday so I'll leave it at that. 3. I don't think so. I thought about that, but welding that plate on with its own internal ribs, plus the arms own webbing made it so heavy and stiff that I don't think adding more weight would have made a difference. I was experiencing more flex in the arm than vibration. The table vibration was really the issue probably due to a large flat surface being elevated by small points. So rt of like putting an air hammer against a flat sheet of tin and letting loose. 4. I thought about that too and did a few camera shots but its really hard to see the difference on a video. Its more felt. How your own hands respond and the smoothness (felt) when cutting. I do get the point though. Would like to see your finished Eliminator. Let me know how it comes out. Shoot me a pic. I have an email on this page you can use. Thanks Don😃

[@oddshot60]

I have yet another question. I really like the idea of using the Flex Glue to hold the weight in place for the reason stated. But, up here in the mountains of NoGa, steel or iron is mighty hard to come by and very expensive to buy. What do you think of using concrete, especially if some holes are drilled in the webbing of both the table AND the frame? Big enough holes would allow the concrete to flow from void to void and allow the installation of some rebar or other steel wire for strength and prevent cracking. It might not have the weight of steel or iron, but done correctly, I don't think it would ever flex. This could eliminate all that cutting and welding you did. The best part? An 80 pound sack of concrete is only $6.00 at the Home Depot. Crack and shrink resistant stuff is about the same for 50 pounds.

[@donsengine3158]

You know I thought of that too.... But, my past experience with concrete to metal in that sort of application was less than good. I only addressed low frequency vibration in this video as thats what causes a 14 tpi blade issues. Its the high freq from a machine tool that will do in concrete. Think sonic cleaner. The metal will transfer that high freq into the concrete and you'll end up with a bunch of sand between the metal and concrete and have a floating block. If you want to put it in the arm, again I think the stresses of flexing would cause issues. I do believe over a short time the cement would start pulverizing on the outer surface. Basically there's just not enough room to create the kind of mass that would make concrete effective in that application. I find a lot of free and cheap metal just walking around the local rail yard, from my shop scrap bin and leftovers from odd jobs I take on. Have you looked around some of the local scrappers or heavy equipment / truck shop metal bins? If a good guy like you walked into my shop and just asked if he could grab a few pieces from scrap, Ide be good with it. Must be something laying around. Good luck. Don

[@MarkATrombley]

Modern tie plates are steel, where did you find a cast iron one?

[@donsengine3158]

I found a pile of scrap out in the woods where the RR was doing track work a few years back. I'm thinking of grabbing up a few more. Bunch of big spikes and curved hook things out there too. Got some floating around. Thanks for watching. Don

[@kentuckytrapper780]

👍👍👍

[@donsengine3158]

Thanks KT. Don

[@sylvaingervais247]

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