Band Saw Blades

[Munroast]

1500w, 3.5m blade, 15" throat, max blade width 30mm

wanting to resawing wood (rip cut down the wide bit) could be some hard woods! not bothered about quality of cut as long as it is straight. I take it as few teeth per inch is best, but what is optimum

also advice on how to make cuts like this, youtube has many different ideas

we have 1" blades 4tpi but they are useless, won't cut strait (although these blades are often greatly abused and mostly smell of burning) I am wanting to buy my own blades for my own use and as they are not cheap I want to buy something worthwhile

makes, suppliers, specs, general advice would be most appreciated

 

[Deleted member 174758]

Always use a blade which is slightly narrower than the maximum the saw will take. You aim to get 3 to 6 teeth in the work piece on timber - so, for example, a 12mm (1/2in) thick piece would require 6 to 12tpi blade, a 25mm (1in) - 3 to 6tpi, a 100mm (4in) - 1.5 tpi (they don't exist in narrower sizes, so use the lowest tooth count you can). Too few teeth may straddle the work and break teeth whilst too many teeth can overload the gullets, overheat the blade and strip teeth. HSS (bimetallic) lasts a lot longer than tool steel blades if you can get them, but cost more

For ripping the fastest cut is a hook tooth type, followed by a skip tooth pattern. What you need to understand about blades is that if they are ever used on curved work the teeth will always take on a side set (and thereafter be useless for accurate straight cutting) so for the best straight sawing, such as ripping, you need to keep a blade solely for that and take it off the saw when not in use (and hide it). Even then blades may still "lead" to one side or the other, so adjust the fence to match the lead if ripping against the it and not the other way round. If you don't already do so, take the blade tension off at night - the tyres on the wheels will last longer and your blade welds will, too

I used to get my blades from Dakin-Flathers or Lancashire Saw in the main, with a few Starretts, which probably isn't helpful other than to saw that D-F are a long established firm who actually make blades.

 

[Diver Fred]

Tuff saws!

Give them a call.

 

[Munroast]

Always use a blade which is slightly narrower than the maximum the saw will take.

so if the max is 30 then I should only use 25?
why not 30

And where do you run the teeth, at the highest point on the wheel ?

 

[Deleted member 174758]

so if the max is 30 then I should only use 25?
why not 30

Tension. Saws (other than girt great cast-iron framed monsters) are rarely able to tension their maximum allowable blade width adequately, so you normally go one or two sizes narrower. The problem with small saws is that they struggle to get the right amount of tension - a big 24in to 36in industrial saw will generally tension 1 to 1-1/2in blades on a thick body (like a Lenox TCT blade), but they are a lot stronger, heavier and stiffer than a 15in (presumably) bench top size saw. With a sharp blade you can tell if the blade has enough tension - the cut will be perpendicular to the table and straight, whilst if insufficient tension will result in a non flat (cupped or bowed) cut face

Similarly if you leave the saw tensioned all the time three things can happen, (i) the teeth in particular cut into the tyre which reduces the life of the tyre and can lead to rough running and additional vibration, (ii) on lightweight saws you can actually bend the frame, permanently and (iii) by leaving the tension on all the time you are putting the weld under more strain - on a saw where the small diameter wheel is already going to reduce the blade weld life (by constantly bending and straightening the weld several hundred times a minute) you maybe want to rest it when it's not being used.

And where do you run the teeth, at the highest point on the wheel ?

There are two schools off thought on this - but in general I ran the middle of the blade on the crown of the wheel, because I found that if I ran the teeth too far back from the edge of the wheel there's more of a risk of pushing the blade off the wheels, and in any case on some smaller saws, like the Startrite 352 14in bandsaw I had years ago, there isn't enough space in the guides to run the teeth of a wider blade on the crown of the wheel