Alignment of bandsaw wheels??

[woden]

Earlier in the year I bought a secondhand - though in good nick - Rexon BS3050AL 12.5" bandsaw. Having used it quite a bit now I'm beginning to wonder if there's something wrong with it.

It's to do with the alignment of the wheels in relation to each other - the top wheel is a quarter inch or more closer to the front of its case than its counterpart below. This means that to ensure the blade actually runs on the bottom wheel I'm having to track it to the back of the top wheel - and its worked its way off the top wheel a few times as a result!

The bottom wheel is fixed in place and so can't be moved. On the other hand, while the top wheel is on a threaded arbour and can be moved it's already as far back as it can go.

I've just phoned Rexon but missed there technical team so will give them another buzz tomorrow. But does anyone here know if this is normal/intentional on a bandsaw or is instead likely to be a fault?? :?

 

[Steve Maskery]

There should be some adjustment somewhere for the bottom wheel as well as the top. Tracking the bottom wheel is something most books and articles skip over and wheel alignment even more so.

First, can I ask you how you know that the wheels are not in alignment? I'm not saying they're not - I have no idea about your machine - but it's just that on many machines this is very difficult to ascertain.

If you can, try the following:

Remove the blade and tilt the table as far as it will go. Use a long straightedge (I used a saw track) up against the wheels. They should both touch the straightedge at the top and bottom of each wheel.

If they don't then, yes, they are misaligned.

Is the machine direct drive or belt driven? If it is belt-driven you should be able to move the whole axle in or out. If it is direct drive then it is more difficult, but look to adjust the whole motor in or out. Is it mounted on a plate? You could pack it out but 1/4" is quite a lot for packing.

Put the blade on the machine, add some tension and track the bottom wheel so that it runs centrally. Only then should you track the top. That way you should be able to get it central on both and eliminate, rather than just compensate for, drift.

HTH
Steve, who's currently filming a bandsaw DVD!
PS do you have any pics of the bottom wheel and axle?

 

[Digit]

The bottom wheel has to attached to a shaft whether direct drive or belt driven, short of it being welded into place it must be movable.

Roy.