Changing blade on bandsaw (Clarke CBS190 7.5")?

[Mr. Clueless]

I think that's the exact model that it is (the clarke in the title). Basically i just want to know how to put it on (properly).

The old blade snapped so i got a new one in from machine mart & had a go at changing it. I think i figured it out right. I slackened off the top wheel & fed the blade on making sure it was central on the wheels (as best as i could). The blades teeth were pointing downwards.
I then tightened it up as much as i thought was ok & checked the blade moved 'straight' through the guide (i'm calling it a guide but i'm not sure of it's proper term - the bit where you cut).

Started it up & there were a few sparks around where you would cut but this stopped soon enough.
I cut about 4 test pieces & all seemed well until i started hearing a quick change in noise so i quickly stopped it, opened it up to find the blade had almost slipped off the wheel both top & bottom.

I'm not sure what to do so i'm asking here. I thought i'd tightened it enough. Am i supposed to tighten it as much as i possibly can? But then can't you overtighten & put too much strain on the blade?

Help welcome.

 

[Burnerman]

You may notice that bandsaw drive wheels aren't actually flat - they have a slight curve, called a crown. When the blade is spinning, it rides onto the top of the crown, keeping it in place. Only tension the blade if this is actually happening, and adjust the top wheel alignment so that it can occur.
There are usually two adjustment wheels......one pulls the top pulley up to tension the blade, the other moves the tilt of the top wheel, to set the 'tracking' of the blade - as it is called.
John

 

[gregers]

yeah total pain in the arse aint they.
ive got a draper version and it can take an age to get it set just right.
what i do when the blade is on is run it round a few times by hand as fast as i can
that way if it stays on then it should stay on once its plugged in and turned on.

 

[Mr. Clueless]

I got it in the end thanks.

I think it was the tilt knob that i needed to tweak which was causing the problem. I just loosened everything & i think this was the issue. It's sorted now though.