Tuffsaw bandsaw blades a bit long.

[PAC1]

Hmm I put the 3/8th Tuffsaws M42 blade on today I could have wound the tension further but a quick lateral test told me it was ok. So how much lateral movement do you have with the guides at the full 12 inch cut. I had about 1/4 inch

 

[Jmac80]

Hmm I put the 3/8th Tuffsaws M42 blade on today I could have wound the tension further but a quick lateral test told me it was ok. So how much lateral movement do you have with the guides at the full 12 inch cut. I had about 1/4 inch

will check tomorrow pac, may do a couple of wee videos also

 

[woodpig]

The Tuffsaw blades for my Record BS300E are not that easy to get on and could do with being a bit Longer!

 

[Steve Maskery]

Do a swap!

The thicker 3/4" blade would account for the difference in tension, but I don't have an explanation for the 3/8" one.

 

[woodpig]

When I get a minute I'm going to attempt to get an accurate measurement of MY machine and order blades by length, not machine model. This should prevent any future problems.

 

[Baldhead]

Are you comparing like with like? I.e. width and thickness as well as length?
The general rule is that the more steel there is in the blade the greater must be the tension.So wider thicker blades will need more tension, even if they are the same length.
S

Steve in my case that would explain the difference in tensioning the blade, Record supplied a 3/8" blade, the blades I bought from Ian are 3/4", both blades are approximately the same thickness. I am not complaining about the blades supplied by Ian, it cuts straight and true although the tensioning is at its maximum, Ian supplied exactly what I asked for i.e. A blade 133" long. I am not concerned about the tensioning as I slacken the blade off after use with the 'cam action tensioner'

Baldhead

 

[Jmac80]

Hello
Could fellow bs400 owners do me a small favor please and compare your machine to my photos.

where about is the yellow gauge 2 x screw holes positioned on yours, A bottom or B top or somewhere else?

And how about the screw above the spring, here is 2 pics of mine.

edit: very bottom pic should read tension ON.. sigh (small few mm gap under the screw)

I know the gauge is to be mostly ignored but i'm just interested to see.
Ian got back to me today and is happy to cut a bit of the length, So i shall do that because the tension spring is fully compressed with the tuffsaw blades and it just doesn't feel good lol.

thanks all

 

[Mr T]

How are people measuring blade length? There is talk of comparing them by laying them on top of each other. I measure length by rolling the band across the floor.
Start with the weld on a mark on the floor, then roll it one complete revolution and mark the new position of the weld then measure the length between marks. You should then be able to accurately compare blade lengths.

Chris

 

[woodbrains]

Hello,

With a bit of maths, it is fairly easy and accurate. Install said blade and wind out the slack with tensioning knob. Measure the centre to centre distance of wheel bearings and the diameter of a wheel. The blade length is worked out by adding twice the bearing centre length to pi times the wheel diameter.

If you think one blade is a bit longer than one that is obviously working, then no sums are needed. Install good blade and measure bearing centres. Install suspect blade and measure bearing centres. Twice the difference ( if there is any) is the amount the suspect blade is longer than the good one.

Hope this helps.

Mike.

 

[Duncan A]

If the Tuffsaw blades are M42, they will need more tensioning than a conventional blade. But I would have expected Ian to have mentioned that?

Duncan

 

[marcros]

is there such a gauge that can measure the correct tension on a blade- an equivalent of a torque wrench?

 

[Random Orbital Bob]

There is but its an industrial tool and very expensive apparently. (Many hundreds so never appears in home shops)

 

[Random Orbital Bob]

Getting back to the OP's point. It is a bit odd I must confess. My experience has been good with both Ian's blades (including for older bandsaws) and also for the relative accuracy of the tensioning guide.

My old BS300 tensioning guide was a complete joke and you took pretty much no stock of its position whatsoever. All the tensioning needed to be assessed by all the other usual means (sideways deflection, sound, gut feel etc). So when I installed and fettled the BS400 I was frankly a bit shocked at how (relatively) accurate the guide was. I messed about with 3 different thicknesses, 2 of Ian's and one of Records and the tension pointer was close to if not spot on the calibration for that thickness. I nearly cut my own head off with surprise!!

Then I installed the inch thick 1.3tpi ripper blade designed for deep green log ripping and the accuracy days were over! That sucker took the tension needle off the chart, though in fairness it didn't go right to the very end of the travel on the spring (though not far off).

So it does sound like yours is a fault! Whether its a fault with the blades length or the machine I cant say. What I can say is that I have more faith in Ian not cocking up his welding to length than I do of a manufacturing fault!!

Regardless, it sounds to me that Chas's solution of simply getting a 10mm smaller blade is the pragmatic workaround. How ironic that Ian's blades and service would be so good that it could overcome a hardware problem

 

[Jmac80]

It's a bit of a tricky one that. I call record and they will ask what about the record blade which I will reply oh it's fine,
Instant blame of the tuffsaw blades.
How does your gauge compare to the pics I posted?
Thanks

 

[PAC1]

Not sure it helps but the screws are 1/4 from the top

 

[Jmac80]

Thanks pac

 

[Bod]

To measure a band saw blade length.
Remove blade, tie a short length of cotton/string around the blade, in a tooth gullet. Measure from string to string using a long enough measure.
Repeat measurement at least twice.
The cotton/string gives a definite starting point, and a fixed end. Using welds, missing, bent teeth etc. can all be duplicated further round.

Bod

 

[CHJ]

Spring performance is also a factor, spring may not be tempered correctly, broken etc. all worth a check.
Also tensioning rods are notorious for stripping threads if the base material used is not up to scratch.
Adjustment/location nuts on tensioning rod in correct location?

All of the above could affect the amount of spring tension applied but would do nothing for the drive wheel and coaster wheel centres being wrong in the first place.


How is the lower wheel centred and adjusted for parallel running, can it be lowered, thereby increasing the between centres distance a few millimetres, by adjusting upper and lower centralising bolts for instance as it can on some designs.

 

[Jmac80]

How is the lower wheel centred and adjusted for parallel running, can it be lowered, thereby increasing the between centres distance a few millimetres, by adjusting upper and lower centralising bolts for instance as it can on some designs.

CHL thank you

I think this could maybe solve it?
It is quite a bit higher towards the top as per picture, so if i even just center is that should make a fair difference?

 

[OLD]

I have a similar saw and if i cannot tension the blade as you indicate i put a washer cut in a 'U' in the tension wheel and rod mec. to compensate and readjust.