Snapped Tuff Saw Blade - :-(

[twodoctors]

Using my Tuff Saw Carbon 3/16" 4TPI blade for the second time yesterday, and as the title says, it snapped on me.

I wasn't making big turns, and was cutting slowly (after coaching from Steve Maskery). The only other cuts I've made was to make this box.

Now I'm no expert at bandsaw but I think it snapped at the joint... a rare manufacturing defect for Tuff Saw I'm sure. There weren't any signs of scraping etc. The guides were set up correct.

Emailed Ian last night. Tried calling this am but no answer. Hopefully it's not me...

The other thing to say is the kerf is quite big with 4tpi. I wonder whether I'm better off with 6TPI next time...

Adrian

 

[Sawdust=manglitter]

That seems a very aggressive TPI for such a small blade and deep curves. For bandsaw boxes type work you're better off with something like 14tpi. What does your bandsaw say is the minimum width blade it can take?

Take a look on the TuffSaws website at 'Cutting Types' and then 'Radius/Cutting Shapes' for blade recommendations.

 

[NazNomad]

... I think it snapped at the joint... a rare manufacturing defect for Tuff Saw I'm sure.

 

[twodoctors]

I bought a Axminster 10TPI 1/4" for that purpose but it won't turn steep enough, and even then it was burning rather that cutting. Tried to complete my project with it last night as it just won't turn / cut. Swapped it for the original 1/4" 6TPI and it was no better turning-wise. 14TPI would be hopeless.

I did ask Ian which blades I can use and he said don't go lower than 3/16"

I should mention that i have a baby bandsaw (Guild aka Argos one with 80mm max thickness).

Hopefully I'll hear from Ian soon.

Adrian

 

[Alexam]

Would be better with a 14TPI, as I use all the time. Ther blaqde you are using would be more for much deeper cuts. The 14TPI is a much smoother cut.
Malcolm

 

[twodoctors]

But my bandsaw is weak and feeble! 10TPI was burning its way through, especially on turns, and it's Axminster blades. OK, not Tuff Saw, but they are not bad either I heard from here.

Try to catch Ian later and see what he says.

Adrian

 

[Alexam]

I bought a Axminster 10TPI 1/4" for that purpose but it won't turn steep enough, and even then it was burning rather that cutting. Tried to complete my project with it last night as it just won't turn / cut. Swapped it for the original 1/4" 6TPI and it was no better turning-wise. 14TPI would be hopeless.

I did ask Ian which blades I can use and he said don't go lower than 3/16"

I should mention that i have a baby bandsaw (Guild aka Argos one with 80mm max thickness).

Hopefully I'll hear from Ian soon.

Adrian

Hi Adrian, burning will only take place if you are rurning too tightly, OR because the blade is not cutting completly vertically, as any 'offset' would cause more friction in the wood. I constantly use a 1/4" 14tpi or less and rarely go to a deeper blade unless I am cutting the full width of a thick plank.

Malcolm

 

[twodoctors]

That's what I'm finding. I can't make the turn I want with 10TPI though. I've tried to be brave before, but at one point the wood trapped the blade. Alignment definitely correct. Checked with set squre. It wasn't the steep turn that is advertised by Tuff Saw or Axminster. I wonder whether it's the wider kerf that's allowing me to turn a bit easier, or the narrow blade, or just being a Tuff Saw blade!

Adrian

 

[OscarG]

wow... what happens when it breaks? Does the machine automatically stop?

 

[twodoctors]

It didn't stop.

It was just "snap" then both ends of the blades retracted into their respective "chamber", and the motor kept spinning. Quite safe actually. I was surprised as I was cutting the straight part when it snapped.

Adrian

 

[ColeyS1]

The cut looks rough as fk ! Looks like you're trying to turn to quick, judging by how jumpy,bumpy, ragged the saw cut is.
Coley

Sent from my SM-G900F using Tapatalk

 

[Bod]

Interesting, Argos seem to have stopped selling that machine.
I, to am having broken blade problems, but not at the weld.
I'm getting breaks and cracks in mid blade, which I'm temped to put down to small wheels (200mm diameter).
The cutting I'm doing is straight, in 100mm oak, with a 4tpi blade. (Going slowly to allow sawdust to clear)
The machine is a Fox F28-180, not the best I'm sure, now I've got the defects sorted, it's not bad. Just breaks blades.
E-mail Ian, he'll get back to you.

Bod

 

[novocaine]

200mm isn't considered a small wheel Bod and not likely to overstress most blades (unless you are using a really stiff blade), that sounds more likely that your overworking the machine, overtensioning the blade or getting sawdust between the wheel and blade (unlikely). at 100mm, you are pretty much beyond the ability of your machine I'm afraid.

as to the OP, how have you setup the thrust bearing? does your machine have the rubbish metal side guides? I'm wondering if you've overheated the blade by having it run on the thrust bearing (top or bottom) or it's pushed out of line over one of them so the side guides are rubbing (you can get away with this on bearing side guides, not with solid guides like these cheap machines have, mine included at the moment). it's a very narrow blade for that tpi, not much material to support between the teeth and not much to weld too. you are correct that the kerf is what lets to take a tight turn, the back of the blade needs the space to move in the kerf of the cut, if it's to tight you get what you are seeing, lots of staggered cuts as the blade moves between wider sections were it's force to cut the sides.

 

[twodoctors]

The bearings are set up just like Snodgrass video suggest: free on normal run, just touching when cutting. I cut it very slowly now, and make sure there's little/no resistance when I move. The side guards are also free from the blade with less than 1mm gap (and there is gap). I have thought about upgrading the guards, but considering I paid £40 for it, and new all bearing guards are about £50, I don't think it's a good move. This is only a hobby for me (I have other expensive hobbies!).

Ian has got back in touch, and will send me a new blade soon. I did ask him whether I can get away with 6TPI (I know 10 TPI doesn't cut very well). The kerf I get with the 3/16" 4TPI is no worse than the 3/8" (edited) 4TPI Aximinster that I use for straight cut. I shall wait for his reply.

 

[nev]

Blades break, even Tuffsaws :shock: but he'll re-weld or replace it if it breaks at the weld.

Coincidentally I had two arrive yesterday and out of curiosity just went out to see how tight a turn I could manage with one of them .
This was a (73") 6mm (1/4") 10tpi Supertuff carbon, setup as per the Alex Snodgrass link someone posted a day or two ago on my small Woodster2 saw, with guides made from assorted bits of wood and plastic chopping board and partially seized thrust bearings, very far from a quality tool.

Admittedly this is an unknown pallet wood, probably a pine of some sort but I had no issues whatsoever cutting pretty quickly through this 3 inch block.

As you can see a 20mm diameter semi circle was simple enough as was the larger 'box' cutout with a few tighter radii and with a very good finish to boot.

So possibly there may be some improvement you could make to the setup on your saw??

I shan't try and second guess Mr. Maskery's tuition tips as I'm sure he's forgotten more than I'll ever know about bandsaws.

 

[novocaine]

The bearings are set up just like Snodgrass video suggest: free on normal run, just touching when cutting. I cut it very slowly now, and make sure there's little/no resistance when I move. The side guards are also free from the blade with less than 1mm gap (and there is gap). I have thought about upgrading the guards, but considering I paid £40 for it, and new all bearing guards are about £50, I don't think it's a good move. This is only a hobby for me (I have other expensive hobbies!).

Ian has got back in touch, and will send me a new blade soon. I did ask him whether I can get away with 6TPI (I know 10 TPI doesn't cut very well). The kerf I get with the 3/16" 4TPI is no worse than the 1/2" 4TPI Aximinster that I use for straight cut. I shall wait for his reply.

I have a similar saw, hence questioning, but I can cut those radius with 1/4" 6tpi blade, which suggests that something just isn't right with your saw. the guides is the first place to look, but if it's like my saw, it might not be tensioning enough either. I found that out the box the tensioner didn't have enough movement before it topped out to tension the supplied blade (or the one's I ordered in the correct size) which meant a blade that wouldn't turn without flopping around, lots of stress on the blade and possible snapped blade. I shimmed the upper wheel mount to give me 1mm more movement and achieved the proper tension and can now cut curves properly. how are you checking tension? do you have a picture of your upper wheel and tensioner arrangement?

 

[twodoctors]

You have a bigger machine than me. Mine only takes 1400mm blades, so I'm guessing my motor is also weaker than yours. It's an Axminster blade as well. The kerf is thin but won't turn enough to for me. I'll give it another go tonight on some "scrap".

 

[Alexam]

Using my Tuff Saw Carbon 3/16" 4TPI blade for the second time yesterday, and as the title says, it snapped on me.



I wasn't making big turns, and was cutting slowly (after coaching from Steve Maskery). The only other cuts I've made was to make this box.




Now I'm no expert at bandsaw but I think it snapped at the joint... a rare manufacturing defect for Tuff Saw I'm sure. There weren't any signs of scraping etc. The guides were set up correct.




Emailed Ian last night. Tried calling this am but no answer. Hopefully it's not me...

The other thing to say is the kerf is quite big with 4tpi. I wonder whether I'm better off with 6TPI next time...

Adrian

Just been looking at the first photo again. Looks like the cut is in two directions rather than straight curve and could account for the very wide kerf? Probably my poor eyesight. ? :roll: :?: :?:
Malcolm

 

[Steve Maskery]

It's easy to over-tension a narrow blade.
Using a finer-tooth is fine as long as you don't mind taking it slowly. Personally, in the context of cuts for box-making, I wouldn't try making straight rip cuts with a 10 TPI blade in anything thicker than fairly thin stuff, say up to an inch or so. If you are making boxes that are 4 or 6" deep then a 10TPI blade would clog. They would on my machine, anyway. But there are people here who make boxes much more often than I do and I'm happy to accept their experience.
Bandsaw box cutting is always a compromise of fine tooth for a fine finish but big gullets for good clearance, especially when ripping off lids, etc. The two don't easily go together.

 

[Bod]

200mm isn't considered a small wheel Bod and not likely to overstress most blades (unless you are using a really stiff blade), that sounds more likely that your overworking the machine, overtensioning the blade or getting sawdust between the wheel and blade (unlikely). at 100mm, you are pretty much beyond the ability of your machine I'm afraid.

I know that I'm really asking too far much from this poor little machine, 100mm deep cut over 1000mm long, but straight, in oak. Those cuts do take a long time..... I do go slow enough to allow the blade to run at full speed, and have vacuum extraction on.
Over tensioning the blade, this machine has a spring tension mechanism, the spring doesn't appear to have variable compression rates, and always has space between the coils, but I will try it with lower blade tension.
Thanks for the reply.

Bod