Air-tensioned band saw

[Dan Hintz]

I don't recall seeing anyone post this, so here goes:
http://www.youtube.com/watch?v=oDCTa16aHh0

[Tai Fu]

It sounds complicated, and bandsaw tension does not really require precision. I mean as long as the tension rod is acme thread it works without fail...

[Peter Quinn]

Interesting adaptation. Solves the original design problem, not sure the added cost is. Value on that level machine? Funny, my Italian saw has the tension wheel in a very convienent place, it adds tension quickly so is not burdensome to adjust, and creates a lot of tension as required. He has solved a problem I don't have. My solution was to get rid of the 14" band saw!

[nicholas mitchell]

A pretty cool solution to a problem that doesn't exist.

[Bruce Page]

I don't think I would trust it. I would like to see a tension gage mounted to the blade to quantify how much tension he really is getting.

[ken masoumi]

If the compressor is out of commision then so is the bandsaw unless the manual adjustment is still functional.
It's not a bad idea if you have a hard to reach adjustment knob or very tall bandsaw .

[Gus Dundon]

It's may be smart idea it but I'm not buying it.

[Judson Green]

Looks like the guy would need to get on a latter if he didn't automated somehow.

Thankfully I'm not vertically challenged.

[Jim Matthews]

A pretty cool solution to a problem that doesn't exist.

Beat me to it; it's a solution in search of a problem.

Bandsaws are elegant, when simple.

[Rod Sheridan]

I don't think I would trust it. I would like to see a tension gage mounted to the blade to quantify how much tension he really is getting.

I would actually like it better than a spring with unknown calibration.

Since he knows the air pressure and the piston area, the rest is easy...........Rod.

P.S. I wouldn't bother with his solution, larger bandsaws have good springs and convenient adjustment systems, he's solving a problem that better saws don't have.

[Bill Rhodus]

Worked on large band saws for years (6 ft sawmills) and they had nitrogen chambers on the tensioning jacks to dampen vibrations. Never seen where this was needed in a shop band saw that was fed at a slow speed.

[Tai Fu]

Although should the airline leak during a cut... the result can be catastrophic.

[Ole Anderson]

Naysayers! While potentially expensive, I absolutely love the idea. For me the problem does exist. There is no quick release on my BS for blade tension, so it usually gets left at full tension for long periods of time. The spring gauge is a very coarse approximation of tension. Reaching up to crank the tension knob is a pain. If the blade mfr lists the correct blade tension in psi, it is an easy calculation to set the air gage psi to achieve the exact required tension. Now off to Books A Million to pick up the April/May copy of American Woodworker. I have shop air so this is exactly the type of shop project that keeps me going. IF I can keep the cost reasonable. In any event it should be way less expensive than upgrading my $400 14" Craftsman Professional to a fancy Italian model.

[Larry Edgerton]

I like it. I change blades a lot and it would save some time. My 20" Delta is not so convenient. I'll never do it, but I like it.

Ole, I buy my air cylinders off of ebay. A lot of production companies change them out on a schedule or use new with new setups and then sell off the old. Have had no problems this way and they are a lot cheaper than at a supply house.

Larry

[fRED mCnEILL]

Great idea. It is reccomended that blades be untensioned each night to preserve the blades. This makes it easy and I supsect would be cheaper that the lever tension setups you can buy. Only difficult part would be monuting the air cylinder.

[Rod Sheridan]

Great idea. It is reccomended that blades be untensioned each night to preserve the blades. This makes it easy and I supsect would be cheaper that the lever tension setups you can buy. Only difficult part would be monuting the air cylinder.

Hi Fred, I've heard that before, yet have never seen a saw in industry de-tensioned after use.

Have you seen any info on that from blade manufacturers?

Regards, Rod.

[Tai Fu]

Now that I think about it, I never seen anyone detension bandsaw blades in any workshop I know of... but then I don't know how often they change blades.

[Bruce Page]

Hi Fred, I've heard that before, yet have never seen a saw in industry de-tensioned after use.

Have you seen any info on that from blade manufacturers?

Regards, Rod.

I have worked in at least a dozen different machine shops from small to hundred man shops and never saw anyone, including myself, de-tension a blade. That said, I didn't have to buy the bearings or blades for the machines either. My MM is easy enough to de-tension that I just do it.

[Frederick Skelly]

Great idea. It is reccomended that blades be untensioned each night to preserve the blades. This makes it easy and I supsect would be cheaper that the lever tension setups you can buy. Only difficult part would be monuting the air cylinder.

I do it every night (at home) on both my bandsaws. Its easy on the Rikon - theres a tension relief lever. On the jet, I have to turn the knob (and retension before next use.) Ive seen this in various books and articles.

[Edward Oleen]

Hey, my Powermatic PWBS-14CS came with he Carter guides and the Carter tension release from the factory. I bought an Iturra Design band-saw tensiometer and use it once for each new blade. I note the reading on the saw's tension adjustment and make note of it where I keep the blade. I have added a much finer scale on the tensioning system, and my tests show that my repeatability is quite good.

Problem solved.

His is a neat idea, though - I could see using it for blade adjustments on my table-saw for lift and bevel, and on the joiner and planer, and the drill press and the router lift and the....

I note he didn't mention the cost of the hardware...

[Larry Edgerton]

It does give me an idea for an air powered drill press......

Larry

[Ole Anderson]

I note he didn't mention the cost of the hardware...
I picked up the magazine article, he lists all of the parts, all new, most sourced from McMaster-Carr, for about $275. I'm sure you can do better by working off Ebay.

[Brian W Smith]

"IF" I was doing it,which ain't too likely..........would probably head twds a lever arm system.The air cyl would be out,away from the slider part.The arm's ratio could then be tailored to increase or decrease the amt of force applied by the cyl.Just sayin,don't think we'd be attaching the cyl in a direct line with the adj slider.Interesting idea......but theres other,way more pressing things in the shop that need attention,haha.

[Frank Drew]

Great idea. It is reccomended that blades be untensioned each night to preserve the blades.

Oliver recommended it but for preserving the tires, so that you didn't eventually get ruts. Even with a conventional tensioner, it only takes half a minute or so to either tension or release the tension, so I made it just a habit at the beginning and end of my workdays, like turning on and off the heat, or the lights.