Thread: good blade but Bi-metal or tungsten tip

A bimetal or TT will easily cut mild steel, the trickier stuff to watch out for is glass, rocks, concrete and hardened steel stuff like tek screws which the carbide blade aren't going to like much either.

Are you planning to sharpen your own?

Tip - dock 150 mm off the ends of the log as this is often the hardest and dirtiest part and it's normally what knocks the stuffing out of any blade.

I have an old upright SR 500 Meber Bandsaw (Italian), with a 50 cm diam flywheel. It's cutting blades are almost 4 m long, similar to your size Steve. Its cut a lot of difficult and very hard woods over the years.

The best precision blades I have found are made by Lennox (US). The smallest blade CT (carbide tipped) blade was a 1" (now its 3/4" it seems). At about the price you were quoted. I just replaced my old blade finally after years (part time) of straight cutting. It’s cut through many nails. I think its a 3 TPI Lennox Trimaster. With such coarse teeth one wonders how they can cut logs so smoothly. My saw could do with a bit more power and a bit more blade speed though. Its blade tension is also set to its limit. Blade has to be very tight I was told.

Next I will try the just arrived “resaw blade” with even fewer teeth (fewer teeth, lower the price). I've also ordered a bimetal blade at US$65 or so to try from them. I know it wont be anywhere near as good or last but ... I'll give it a try. To me the Lennox blades have been “the ultimate cutting experience”.... I use that phrase honestly not for promotion!

Over 20 yrs I have tried and used up dozens of blades, mostly carbon steel. Then I tried a range of thin (narrow kerf) high tech “alloy blades”, then finally bi-metal which were all OK too, before I finally decided to try these carbide-tipped precision-made (ground) Trimaster blades. They were only available as 1" blades then and cost US $160+ ea plus delivery 10 yrs ago They can cut steel and the toughest alloys it seems. Note that I have yet to try the 2 new re-saw blades from same source.

The CT blades I have used produce a very fine wood finish when saw and blades is set and used properly, requiring little post cutting sanding. Love that! But were never designed to cut small items like pen blanks. When I first tried the Lennox CT (Tri-Master) 10 yrs ago I was so delighted I just wanted to cut wood all day! The old blade is noisy now, still cuts OK, but requires more force and is just tired. I am not sure if they can be touched up but that would require diamond shapener and knowledge how for best angles etc.

Prices for the newest Lennox Blade 1.3 tpi 1” Resaw Blade was US$175 (over US$200 for a 3 tpi CT Trimaster blade). This was via a US sales agent with a US$65 delivery cost.

There is a bandsaw blade supplier (Aust Bandsaw Co in Seven Hills NSW) who may be of help with these or similar blades if you do wish to import them directly.

Hope this is helpful.

Euge

You could get a second quote from Henry Bros in Sydney
they are also open to discussing what might be best in their opinion

link

I don't know much about bandsaws, and what little I know was learnt around bands 100mm and wider, so take this for what it's worth:
getting the right hook, pitch, rake and set is going to have more influence on performance then blade construction will. Find the right mix for your timber, and only then think about extending life / increasing performance. The right band in the wrong material will cut better then the wrong band in a better material.

high carbon bands are cheaper, so if you're expecting trouble then that's the blade you want to write off. But part of that has to be learning that some logs are better off not being milled at all.

High carbon bands tend to be able o take a hit better then tipped blades. The reason being that the tipping metals are either hard or abrasion resistant, but also tend to be brittle. Steel diets or bends where TCT or stellite will chip. You can't reset a chip.

I don't know if anyone does stellite tips on bands that small but that would be my preference if it's available.

Hi Steve,
Have you asked " McDiven Saws " in Williamstown, Vic.
Seems that those Lennox Blades are the ones.
Not sure if McD. wood have them, unless you ask.

McDiven Saws Pty. Ltd.
9 397 1458
328 Kororoit Creek Road,
Williamstown North, 3016.
www.mcdivensaws.com.au

Hope that helps.

I've had good success with the Lennox blades, both the Bimetal 1 tpi 1 1/4" wide and TCT 1.3 tpi 1" wide, both blades have seen their fare share of nails and various other disasters, the 3/4" wide 3 to 4 tpi variable pitch resaw is also an excellent blade although it doesn't last too long in dry hard stuff.

As far as whether one is better than another when it hits a nail is pretty much the luck of the draw, I've had both run into a nail and all I've had to do was pick the bits of metal off the teeth, other times it has taken teeth off or all the set off one side, there have been times I didn't detect a change only to find a little black spot on the cut face somewhere to a chunk chunk chunk and the blade wandering off and then I can't complete the cut.

Usually now I use the Bimetal for green stuff and TCT for dry stuff but both will do either.

I use these blades on a basic upright BS and one thing I can find to be a bit troublesome is build up on the blade which then can lead to a wandering blade especially on green resinous stuff, mango being one, I mounted some brushes that run on the blade which keeps the blade a lot cleaner, I'm guessing yours is used outside so you should be able to run some water/soap/? mix on the blade to help keep it clean. I would also recommend you go as wide a blade as you can.

Have we seen a pic of the BS?



Pete

G'day all, Some excellent responses, so l thank you all very much, l will reread them all several times, then try some different suppliers (Henry's and Mrdivens).

As for pictures, once l clean it up a bit - then l'll post some shots.

Its great to be able ask questions and get quick responses, from a broad spectrum of wood workers. all the info is very useful.

l can't wait to cut some of timbers, last year we cut up some green "apple-jack", well we think it was, but it was so full of resin, it was bleeding everywhere, the timber ended up being useless, dried it was very light (no guts), no even good for fire wood, but it was good to see what was inside.

Thanks again
steve

I've hit a temporary snag, once l started ringing the blade suppliers and mentioned its home made and running on 15" cut down rims, most said l was wasting my time as the blades would be too stressed and break, yes they are right.

So - thinking l had an answer l went and got a 19" and 18" rim (didn't have 2 of the same) l can shimmy up one set of bearing etc, until l get another rim the same size or just wait (no shimming)

The suppliers also were worried that there were no tires/tyres, but l mentioned if the blade is wider than 25mm then the teeth are not touching anything but the timber, as the blade contact area on each rim is a maximum area of 25mm wide (yes - pictures coming)

l got to thinking, l really need 24 or 28" wheels, remembering there was a guy who built a timber (wholly constructed) B/saw, l will try and find out how he built his wheels?

As the saying goes "sh-t happens" then some, just got a tax bill from ATO payed in too much super (not happy)

Thoughts - anyone?

Originally Posted by Not enough!!

. . . . . Thoughts - anyone?

What' HP and sort of motor are you running and what linear band speeds do you have.
If you use the same size pulleys as for the 15" rims you now have 19/15*100% more band speed.
It is possible to have too much band speed which will create more friction and cut less wood.

Hey Bob, l'll have to measure the pulley, like the saying goes, a "picture' will be invaluable so l will get some shots either tomorrow or Fri, whenever l get out to the farm.

The pulley is smaller than the rims and the motor is only 6hp, yer l know it needs a bigger "donk" but l just feeling my way around at the moment, l may have brought a headache but the learning curve will help me and others if they choose to go down this path.

Funny one - when l spoke to one salesman of Blades l couldn't believe how rude/blunt he was, but l could see his side = "you buy the blade it breaks you blame us", whatever happened to good old sales diplomacy?

Originally Posted by Not enough!!

Hey Bob, l'll have to measure the pulley, like the saying goes, a "picture' will be invaluable so l will get some shots either tomorrow or Fri, whenever l get out to the farm.

The pulley is smaller than the rims and the motor is only 6hp, yer l know it needs a bigger "donk" but l just feeling my way around at the moment, l may have brought a headache but the learning curve will help me and others if they choose to go down this path.

Don't stress too much - just take it slowly

The golden speed is said to be around 5500 FPM (Cooksaw website) any more that this and the extra speed just creates more friction. The smaller the motor the more closely you need to stay at or below this speed.

Funny one - when l spoke to one salesman of Blades l couldn't believe how rude/blunt he was, but l could see his side = "you buy the blade it breaks you blame us", whatever happened to good old sales diplomacy?

Yeah I've been through all that - but I can understand where they are coming from, Band saw milling is nowhere near as easy as it looks.

From memory my blade speed is around the 4000fpm, the upside of the higher end blade speed is you can then have a faster cut rate, (if you have the power/torque) the downside is (as the supplier alluded to) and that is the increased possibility of blade breakage especially with small wheels, every time the blade travels around the wheel the outside is stretched and the inside of the blade is compressed, which is further amplified again with thicker blades, then in the straights the blade is under tension from the initial blade tension, this constant cycling fatigues the blade and it eventually breaks.....like this....
bandsaw blade crack.jpg
The tell tale is when the blade starts to move back and forth in the guides (something has changed) I switch off and run the finger nail on the blade which will catch in the crack if I can't first off see it, the crack usually propagates from the gullet, this back and forth can still happen as a result of a weld that's not as straight as it should be but the key point is an increase in blade movement, if you don't keep an eye out it will eventually go off with a bang and that's a brown undie moment, I've had one go off and it wrecked the tyre on the wheel.

I'd got 4 or 5 sharpens out of it which is about the life of the tooth tip so time to chuck it.

Polish the gullet and the blade, (at least free from scratches and rust) large wheel diameters, slow band speed, minimum amount of initial tension, minimum thickness, wider band are all things that help with blade life.


Pete

Thinking outside the square (or in this case the round) for a minute:

See, I've got this idea been floating around in the back of my head for a while. I've bounced it off a few "experts" but they all tell me I'm wrong, no way, we don't do it that way, etc etc. Thing is - I've never got a good answer as to why it won't work, aside from the fact that "we don't do it that way".

To my mind "we don't do it that way" is the poorest reason to not innovate.

So... every time that band goes around the wheels its forced into a curve. Obviously the tighter the wheel, the more stress is placed on the band. Stress equates to metal fatigue which is what ultimately kills the band - it cracks. This is why the bigger the band the bigger the wheel is right? The 4" bands I played with ran on 48" wheels. The 6" bands run on 72" wheels... all designed to reduce the tightness of the curve so that the stiffer wider far more expensive bands last longer before they die.

Ever seen the maths on increased track chain life in a high track bulldozer? By putting in a third "wheel" ( okay, an extra idler and lifting the sprocket higher) it reduces the angle of curvature that the chain is in a curve, resulting in less stress on the chain and less wear. Track chain wear reduces dramatically.

This is engineering 101 stuff. If we want to reduce the tightness of the curve that we force the band into... just give it another wheel. Mount the drive up high in the middle and have two lower guide wheels as per normal so the band now runs in a triangle shape. Tension by lifting the high mounted drive wheel higher/lower to increase/ decrease band strain. No dust gets to the drive wheel because it falls off first increasing the life of that component. Instead of the band having to do a 180 degree curve around two wheels, it now only needs a theoretical 120 degree curve. That should give a theoretical increase in band life due to reduced fatigue by something like 33% shouldn't it? Probably more because metal fatigue is an exponential thing.

The cost? An extra rim and a longer band. Longer bands have more teeth, and more teeth for the same volume of wood equals less frequent sharpening. Less frequent sharpening = more time cutting = what? Probably a revenue neutral kinda thing really in that respect... unless you total a band on something rather then letting it die of fatigue.

But all I ever get told when I suggest this is "won't work, we don't do it that way" . Just once, just once I'd like someone to tell me why it won't work for some reason other then that.

Oh look... squirrel. ( ie sorry for getting off topic)

Originally Posted by John.G

By putting in a third "wheel" ( okay, an extra idler and lifting the sprocket higher) it reduces the angle of curvature that the chain is in a curve, resulting in less stress on the chain and less wear. Track chain wear reduces dramatically..

There are plenty of 3 wheeled bandsaw out there just google "3 wheel bandsaw" for pictures.

The mains reason for using three wheels is to sgenerate wider throats than two wheeled saws.

You will also discover they break blades faster than 2 wheelers.
eg http://www.woodworkingtalk.com/f12/d...g-blade-43109/

There is a big difference between tracked vehicles tracks which can rotate around each other and the solid material used in BS blades.
The 120º angle of deflection possible on the 3 wheelers does not change the fact that the blade is still forced into a circle with a small radius.
Plus it does this 3 times x 120º in each revolution so in effect it is bent through 360º anyway.