Snapped Tuff Saw Blade - :-(

[twodoctors]

Well, I proved myself wrong.

It's 1" radius, but it is do-able. Not far off 5/8", but my bandsaw just won't take it. If I twist it any more the blade will slow and eventually get stuck. I think on a more powerful bandsaw it's not going to be as big a problem.

The one on the left is with the 3/8" 4TPI; next two is the 1/4" 10TPI. You can see burn marks easily, and that's me taking it very very very slowly. Almost 10sec pre mm if not less. Some of the turns I did struggle with. I had to do what I do with scroll saw: come back, turn and let the blade widen the kerf, and then push on (and repeat if nothing happens). Really really struggle with the third piece, esp in the top left corner, I thought I might not make the turn and the whole box destroyed. Stuck there for a fair while. Same with the last turn (bottom). I went anti-clockwise for all of them.

Now my blade won't cut straight (as expected). I do really mean it though:

This was done with the fence on. You can see how it wants to cut to the right. Eventually correct itself a bit, then I was stuck in a few spot (circled), and jammed at the last circle. Had to remove the fence and try to finish it off (but pulled to the right). I can't even turn it left as the blade will just jam. With the skewing and friction burn etc and very slow cutting (blunt already?), might have to chuck that into the bin soon.

I wonder whether I should ask Ian for a 6 or 8tpi instead.

Adrian

 

[AJB Temple]

You need to start a thread entitled "I'm looking for a better bandsaw"

 

[twodoctors]

Anyone?

;-p

 

[MARK.B.]

could the slow speed be causing some of the problems you are having with burning ? the problem you are having cutting a straight line could ( possibly/maybe) be down to you having twisted the blade .

 

[AJB Temple]

I was being serious. It sounds very much like you need a more powerful saw for what you are trying to do. And one where you can adjust the blade tension. I don't make many bandsaw boxes but when I do my fairly modest 16" saw will easily handle what you are doing, quickly and easily with no issues of tight turns or burning. I suspect it is partly technique and partly that you are exceeding the capabilities of your saw.

 

[Terry - Somerset]

Although I have not used them Axminster do a back tooth blade which widens the kerf at the back of the balde and I assume creates more room when cutting tighter curves.

Don't know whether Tuffsaws do something similar.

Terry

 

[CHJ]

Anyone?

;-p

How dry is the wood, is the kerf closing up behind the blade and trapping it?

Immediate impression is that the blade is blunt.

 

[CHJ]

It's worth carrying out the cutting performance of a blade the way it's done in this video, you will get a fair indication of if the blade is the problem.

https://www.youtube.com/watch?v=UygEQ-079Ws&app=desktop

Having just licked the tops of the teeth as in this video even an old blade can come back to 'hot knife through Butter' performance.

(warning lousy video technique)

 

[twodoctors]

Sorry AJB. I know what you mean, but this is still a very new hobby for me and can't justify the cost at the moment. Paid (relatively) peanuts for the stuff I have so far, and agree the first upgrade (if any) would be the bandsaw. I've already set alerts on Gumtree and the Bay for used bandsaw in the area.

And yes CHJ, the Axminster blades are the problem. They don't cut very well... at least the 1/4" 10TPI don't anyway, and now it's slightly bent. Fitting the "drawers" back into the box, the last one doesn't go in properly because it's been cut at a slight angle. No issues with the second (first with Ax blade) drawer. And as evident with the test with scrap pine, you can see the blade is gone. Sad as I've only made 2 bandsaw boxes (and these one and 1/2 drawers) with that blade, small one as well. Is it worth a warranty claim? No harm in asking I guess. It's only about 3 weeks old max.

I'm going to give Ian a call tomorrow to get some advice. Here's why:

Left hand drawer is cut with 3/16" 4TPI. Middle drawer is 3/16" (until it snapped) then 1/4" 10TPI, and the last drawer is 1/4" 10TPI "bent" blade. The kerf is massive with the first drawer, but that's not the only issue with 4TPI.

The back of the box was cut with Axminster 3/8" 4TPI. The grain doesn't quite line up with the bigger kerf. Granted I did sand it a little bit to get a smoother edge for gluing, but I probably won't have to do as much with a higher TPI blade. I do wonder whether my 10TPI won't cut because it's not a Tuff Saw blade... as I said it's fairly new and hardly used. The Tuff Saw Premium is a thicker and stiffer blade than Axminster, and I guess that means the quality is better.

So I am getting a replacement blade from Ian for curve cuts: another 3/16" but probably another TPI. I'll probably buy another blade for bandsaw box straight cut, but ask him whether I can get away with using the same 3/16" (probably not). Or even to stick with the Axminster 3/8" 4TPI which I must say cut very very well (albeit bigger kerf).

Something to ponder...

Adrian

 

[Rorschach]

I really think it is your saw/setup and not the blades. I have used Axi 1/4" 10tpi blades for years and find them to be excellent, better than tuffsaws blades based on recent experience anyway.

 

[ColeyS1]

Have you got any pictures of your bandsaw setup ? Looking at your pics, something looks majorly wrong. Your photos and Nevs photos, are miles apart !!!
Even on a majorly underpowered machine, you should still be able to replicate Nevs cleanliness of cuts. Try it on 20mm thick stuff. If you can't,it's either bandsaw setup, or a knackered blunt blade, that's lots it's teeth set.
To be honest if I've been doing curvy cutting for any length of time, it's never been fantastic at doing straight cuts after- I guess curvy stuff wears one side of the blade more than the other.M42 blades are much better at staying sharp for longer. Generally I keep a m42 3/4 blade In the saw for everything, only changing it for a smaller blade when curvy cutting is needed.
Stick with it, it'll be worth it once it's cutting like a goodun.

Coley

 

[Alexam]

I have probably missed it, but which bandsaw and model do you have please?
Malcolm

 

[Eric The Viking]

To be honest if I've been doing curvy cutting for any length of time, it's never been fantastic at doing straight cuts after- I guess curvy stuff wears one side of the blade more than the other.

I quite agree. I get exactly the same problem.

Two things about blade snapping occur to me:

(1) it is easy to overtension a thin blade; you don't really get any warning, and if the geometry is off, for example if the blade isn't cutting at exactly a right angle to the table, you'll be adding that little extra bit of stress that causes it to fail. My saw's frame bends so much that I can set it up for either thick or thin blades, but not both: if it's true and square for one it'll be out for the other.

(2) Like other woodworking tools, bandsaw blades are a compromise: if the teeth are hardened to wear well, the blade is brittle and won't flex well. To an extent you can work round this by only hardening the teeth, but that only works well on bigger blades. Small/thin blades must always be really difficult to make in comparison to bigger ones. And, no matter how well you try, for practical purposes the weld will always be the weak point of the blade, if it is going to be the same dimensions as the rest of the blade. You could make it thicker and stronger, but it would catch. The problem is that the action of making the weld, and to a lesser extent grinding it flat and smooth, changes the composition of the steel and its hardness. And that change is the weakness.: the best made weld will still have that problem, and thus that is usually where it will break. And of the blades you stop using, the reason for discarding many of them will be that they snap - it happens.

Few of us amateurs (least of all me!) do enough bandsaw work to form any statistically-valid view as to the reliability of blades from any one supplier, even less to make valid comparisons. We can say, "this blade cuts better/worse in the way I am using it, compared to others." We can't say with any genuine confidence that Tesco's blades fail more often than Sainsbury's ones.

I like Tuffsaw's blades, but then I don't have statistical arguments to say they are "better made" than others, just that they fit what I want to do and the way I want to use them better than others. The argument that anybody's blades are of themselves better than anyone else's is sterile and false, unless you're testing dozens of comparison samples under strictly controlled conditions. I doubt any blade suppliers do that, as the product is simply too low-value to make it cost effective.

E.

 

[twodoctors]

And I think you are right. And hence I used 4tpi to compensate for the lack of power. But that kerf...

 

[lurker]

I like Tuffsaw's blades, but then I don't have statistical arguments to say they are "better made" than others, just that they fit what I want to do and the way I want to use them better than others. The argument that anybody's blades are of themselves better than anyone else's is sterile and false, unless you're testing dozens of comparison samples under strictly controlled conditions. I doubt any blade suppliers do that, as the product is simply too low-value to make it cost effective.

E.

Can't argue with that.
BUT the reason Tuffsaws has such a fine reputation on this forum is Ian's customer service which is superb.

 

[twodoctors]

The machine in question is a "Guild", sold by Argos until last year I think. Paid £40 for it.

I am fairly sure the setup is OK. 90 degrees, guides 0.5mm ish off, just behind the bottom of teeth. Before it bent it was cutting fine, certainly no problem with the 3/8".

I do need a new bandsaw of I were to progress in this hobby of mine. Although now that I have a router table I might start making "proper boxes". :-O

 

[ColeyS1]

Just had a quick look at a picture of your bandsaw. On the bit that goes up and down (the bit with the top bearings,to adjust for different wood thickness) does it flex alot? I'm just wondering if the up and down locks securely/rigidly ?

Coley

Sent from my SM-G900F using Tapatalk

 

[RogerP]

To be honest if I've been doing curvy cutting for any length of time, it's never been fantastic at doing straight cuts after- I guess curvy stuff wears one side of the blade more than the other.

I’ve found that common to all bandsaws I've owned or used. Once a blade is used to cut curves it never runs true again for straight cuts.

 

[twodoctors]

It does, and I lower it to just above the piece to minimise flexing. It doesn't move on cutting if that's what you mean.

Ian has made a 3/16" 10TPI for me. He's someone who knows, so I'm sure that's the best compromise. Waiting for him to reply on what to use for straight bandsaw box cuts.

I'm a Tuff Saws convert!

Adrian

 

[AJB Temple]

I would think that Ian buys blades in on the roll from an industrial supplier, cuts to length and welds them. Chances are other blade sellers are using the same material. Ian is helpful with giving advice and service.