Oh dear, bandsaw blade goes airborne...

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OPJ

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What is it about Mondays?!? :x

Admittedly, I was rushing, as I had to go out this morning (just got back) and I wanted to get the timber planed up before I left. Over the weekend, I was resawing some oak and I think that just about finished off the 1/2" x 3tpi blade I had been using (it was used and came with the saw, probably Axcalibur, like the others).

As soon as I started the saw this morning, I knew something was wrong as the blade was visibly jumping back and forth; knock, knocking against the thrust bearing. Usually, this tells me that the weld is about to go. I know I should have changed the blade but, "I only had one more cut to make and it was less than an inch thick".... :roll:

You can guess what's coming next...



For very many reasons, I'm glad my name isn't Peter Crouch. Otherwise, that may have tried to take my head off!! :?

Bellow, you'll see that the weld remained in tact (ignoring the stray tooth in the middle) - this is the first time I've ever had a blade break on me and not at the weld.



It gets worse though. Very much worse....



:shock:

Yep, that's the tyre off the top wheel - it came flying out the top of the saw along with the blade!!

You may remember my previous post, where I indicated that the tyre had a few gouges missing from the front edge. Well, I've been happily tracking blades on the centre of 'crown' of the tyre since then and, as I did check at the time, it certainly wasn't loose in any way. But, it's an incredibly clean break; almost like the adhesive between the tyre and wheel didn't hold. I can't imagine the force of a 1/2" bandsaw blade breaking was that strong... You can see that the tyre snapped about 12in away from the join.

Not sure what I'm going to do next, once I've finished crying. :cry:

A new wheel would cost about £200 inc. VAT although, Ian John did give me the name of a firm in South Wales who may able to repair something like this, which I'll probably try next. I'll send Startrite a message as well (even though the machine's out of warranty, being second-hand).

Has anyone had this happen before?

Lesson to all - if you think a blade might need replacing, do not hesitate to switch the saw off!! Learn from my mistake! :oops:

Olly.
 

big soft moose

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bad luck mate but at least you didnt get hurt

i have heard, on here somewhere i think, about some startrites being re tyred with an adhesive cork strip rather than a rubber tyre - ive no idea whether your saw would be suitable for this but it might be worth a look
 

Blister

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I replaced the tires on my old band saw , just the tire not the wheel

NO glue either , Heated them up in a bucket of boiling water and plopped them on :lol:

Big Soft Moose had the saw of me and he has now sold it on

Check with Startrite if you can buy just the tires :wink:
 

newt

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Olly glad you survived. Thats two near misses this weekend Karls being the other, Think I might use hand tools for a while. :shock:
 

big soft moose

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Blister":3nt17wpk said:
I replaced the tires on my old band saw , just the tire not the wheel

NO glue either , Heated them up in a bucket of boiling water and plopped them on :lol:

Big Soft Moose had the saw of me and he has now sold it on
yep its with hanser now - nice little machine and none the worse for the experience - mind you it was a baby rexon , so the stresses and strains are may be a little different to that big startrite
 

Harbo

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Wow another frightening tale, I've never had a blade break - glad you are OK.

I'm puzzled how the blade got out because most of it is enclosed? Is it the momentum of the wheels that pushes it out?

Somebody posted a thread a few weeks ago about replacement Startrite wheels from somebody on Ebay?
And there was one, a long time ago I seem to remember, about getting the wheels re-shod?

Rod
 

big soft moose

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cambournepete":3pk2f4u2 said:
I'd contact Axminster and tell them what happened, assuming you got the saw from them.
As you say, the blade shouldnt break and the tyre should stay on...
do axminster sell startrites ? - i think olly got the saw second hand and the axcalibur blades came with.
 

big soft moose

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big soft moose":3481pkwr said:
bad luck mate but at least you didnt get hurt

i have heard, on here somewhere i think, about some startrites being re tyred with an adhesive cork strip rather than a rubber tyre - ive no idea whether your saw would be suitable for this but it might be worth a look
this was the thread i was thinking of

http://www.ukworkshop.co.uk/forums/star ... ht=bandsaw tyre

HTH
 

TrimTheKing

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Why would you need a new wheel Olly? You can get tyres for these (well you can for other BS's) to be glued on as Blister says, just do that.

How the hell did the blade fly out of the top, isn;t the machine encased at the top? :shock:
 

OPJ

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Hi guys, thanks for all your comments. Thanks also to the mod who changed the title... :oops: No worries. :wink:

Mark, the only reason I mentioned replacing the wheel was because when I spoke to Startrite previously about the gouges, they advised that I would "have" to buy a complete wheel, as the rubber tyres are bonded (apparently!) to and cambered/balanced in the factory. It could be part-BS to get some money in their pockets but, on all other points, the technical guy I was speaking to seemed to know an awful about these saws and bandsaws in general (those gouges I mentioned were caused by a blade break while the previous owner was working with this machine).

By their logic, I'd have to "scrap" the old wheel - in which case, I may as well try replacing the tyre! :p If it doesn't work then, okay... I'll drop a line to Ian's recommendation (Recovery Rollers) and I'm really intrigued by the sounds of these cork-rubber tyres, assuming they aren't too expensive. Especially as you can adjust the camber with standard abrasive paper. :) Looks at the S&S website though, it looks like it could still cost a fair bit, with the required pot of glue (still, only a quarter the price of a new wheel!)

I'll also photograph this in a bit but there is a large hole in the top of the machine's casing - it allows the top wheel to protrude when you're cranking the tension up for a wide blade.
 

big soft moose

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OPJ":30o25gkd said:
I'll also photograph this in a bit but there is a large hole in the top of the machine's casing - it allows the top wheel to protrude when you're cranking the tension up for a wide blade.
was that a factory fitting or a user mod ? - doesnt sound safe to me, could you not build a raised cover.
 

9fingers

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As and when my Startrite needs tyre attention, I intend to glue on some poly vee belting - the type use for the auxiliary drive on most cars.
(the one that drive the alternator, power steering and air-con) They are about an inch wide and seem ideal for the job. The ends should be scarfed such that the direct of rotation closes the join.

Bob
 

cambournepete

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big soft moose":3aqrcmba said:
cambournepete":3aqrcmba said:
I'd contact Axminster and tell them what happened, assuming you got the saw from them.
As you say, the blade shouldnt break and the tyre should stay on...
do axminster sell startrites ? - i think olly got the saw second hand and the axcalibur blades came with.
:oops: :oops: :oops: :oops: :oops: :oops:
I'll keep quiet now... :oops:
 

OPJ

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Here, you can see the hole for the top wheel, which is where the blade (and probably the tyre) made a quick escape:



Pete, yes, I could build some form of magnetic box-guard to sit over it. However, I'm gradually becoming more aware of when blades are going to break so, after trashing the tyre this time, I don't plan to push my luck quite so far again! :oops:

When it happened, I noticed something jump off the top of the saw, heading over towards my wood pile. When I saw the blade hanging over my head though, I completely forgot about it...



Bandsaw is on the right and the wood pile is to the left of my mitre saw setup. If you look just above that green sheet of MR MDF, you can see silvery light with flexible shaft - it's magnetic and I did have it stuck on top of the saw - it's travelled quite some way!! :D

So, when I get her back up and running again, I've decided it would be better off clamped to the guide post behind the blade:



It's a shame Axminster no longer appear to stock this as it's quite a good light. It does have a habit of not working now and again but, I've had the same batteries in there for three-years or so and that giant leap appears to have bought it back to life! (By the way, that glow of light is from the sun, as I have the door open in this shot! :wink:)
 

dickm

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OPJ":6c3mvyjo said:
there is a large hole in the top of the machine's casing - it allows the top wheel to protrude when you're cranking the tension up for a wide blade.
I'm amazed at that. Certainly in your pic, it looks like an original "feature", but surely the machine couldn't be designed to need a hole like that in the top? Seems obvious that in the event of a breakage, there would be a good chance of the blade ejecting like your's did.
 

OPJ

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9fingers":10x85f6w said:
The ends should be scarfed such that the direct of rotation closes the join.
Hi Bob, I just want to check I understand what you are saying...

Obviously, the ends are cut to a 45° angle on the face. Are you also saying that the edge cuts should be bevelled slightly? That looks to be how the bottom wheel on my saw is done.

Well, this morning, I took the plunge and ordered a 2m length of the cork-rubber tyre from Scott & Sergeant (plus the glue and VAT! :x). I only need about 1.2m but, hopefully, it'll be here tomorrow (well, it bloody well should be, £9.99 for delivery!! :x) Startrite have also come back to me and have found a wheel from a scrapped machine (it fell of the lorry! :shock:) and I could have that for around £100. KV Rollers also got back to me but, that was after I'd placed the order (they did seem very willing to help, though :)).

I've said this before but, as I would have to 'scrap' the old wheel anyway, I feel it's worth at least trying to do something with it. I appreciated their advice and that fitting a new wheel with a factory-fitted tyre would be the best possible solution. But, if I can save £50 and put that towards some new blades... :)


Pete Maddex, thank you for the offer. Unfortunately, my wheels are 16in/400mm.

Dick, it looks to be part of the intended design and allows the upper wheel to poke up through the case when you crank the tension up for a wide blade. Otherwise, the saw would have to be several inches taller (increased material costs, etc.) and it was awkward enough to man-handle as it is!! :wink: I may well try to box it in, at some point.
 

9fingers

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OPJ":5yatw4b2 said:
9fingers":5yatw4b2 said:
The ends should be scarfed such that the direct of rotation closes the join.
Hi Bob, I just want to check I understand what you are saying...

Obviously, the ends are cut to a 45° angle on the face. Are you also saying that the edge cuts should be bevelled slightly? That looks to be how the bottom wheel on my saw is done.


Dick, it looks to be part of the intended design and allows the upper wheel to poke up through the case when you crank the tension up for a wide blade. Otherwise, the saw would have to be several inches taller (increased material costs, etc.) and it was awkward enough to man-handle as it is!! :wink: I may well try to box it in, at some point.
I meant only scarfing in one dimension. doing it on 2 axes sounds like a job for a production jig to me.


I don't follow the need for extra headroom when tensioning a wide blade.
Tension is only applied to a blade when the top wheel STOPS moving.
There will be a minuscule stretch of the blade but that would not justify a hole like this.

?? confused of Romsey.

Bob
 
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