I've got your grandfather

[Iwegian]

I found a bandsaw at a garage sale and for ten dollars couldn't pass it up. It is a Magna model 630 from 1959. It is identical to the Shopsmith bandsaw, so I started cleaning it up and replacing parts. My question is as follows...After adjusting the auto track and upper and lower guide bearings I started it with the cover off. The saw blade started at the back of the wheels but slowly crept forward until it was off the guides by about 1/4 inch. Do I need to replace both wheels.....or am I missing something?

[beeg]

What is the amount of cant?

[JPG]

Is the back of the blade drifting away from both the upper(rear) and the lower(front) guide bearings? When it bears against both guide bearings, how far from the back rim of the upper tire is the back of the blade?

If you do not understand the previous question(by Beeg), please say so. We will be glad to explain(this is different from most if not all other bandsaws).

[JPG]

BTW I be curious HOW you adjusted the auto track and the upper/lower guide bearings.

[Iwegian]

What is the amount of cant?

It is "slightly" canted so that the top of the wheel is kicked back. I read quite a bit on the shopsmith bandsaw, but never found anything on the amount of cant...just that it needed to be canted.

[Iwegian]

Is the back of the blade drifting away from both the upper(rear) and the lower(front) guide bearings? When it bears against both guide bearings, how far from the back rim of the upper tire is the back of the blade?

If you do not understand the previous question(by Beeg), please say so. We will be glad to explain(this is different from most if not all other bandsaws).

I will try to answer both of your posts a once. I read and followed your OUTSTANDING post about setting up the bandsaw blade. with the tension adjuster slack,I pushed the blade to the back of both wheels and set the tension. I then started my adjustments with the auto track bearings. I then went to the lower adjuster (because the upper adjuster was set back quite a bit)and finished up with upper adjuster. I rolled it through by hand to make sure it wasn't binding, before turning it on.
I watched it "creep" off the back of the wheels and slowly quit in the middle of the wheel.I then watched it run for about a minute with no further creeping.
I did not mention that I am running a brand new 1/4" shopsmith blade. Originally this saw had rubber wheels with bushings for the auto track and upper and lower adjusters. they have been replaced with the new bearing setup. The Drive and Driven wheels are lined with cork (not rubber) and have NOT been replaced.

[dusty]

Remember why the wheel is canted at all. It is canted in the Shopsmith band saw so as to force the blade to walk toward the back of the wheel. The guide bearings are intended to control how far.

There are those who will tell how much cant and I am one of them but all I believe can be said is that it needs to be canted just enough to run the blade back against the lower guide bearings. More cant is not necessarily better.

[Iwegian]

Remember why the wheel is canted at all. It is canted in the Shopsmith band saw so as to force the blade to walk toward the back of the wheel. The guide bearings are intended to control how far.

There are those who will tell how much cant and I am one of them but all I believe can be said is that it needs to be canted just enough to run the blade back against the lower guide bearings. More cant is not necessarily better.

I agree completely....that is why I'm wondering if I missed something. As I was typing my reply to JPG, I started to think that maybe the cork linings have compressed and with a 1/4" blade is thin enough to cause this problem.

[JPG]

The rear upper wheel blade guide is not adjustable other than laterally. It is fixed relative to the main casting. Ditto the lower wheel guide bearing.

The cant angle then determines the location of the back of the blade as it rides on the upper wheel. i.e. the cant positions the top rear of the wheel a fixed distance from the main casting. Canting too far and the blade rides more towards the center(sound familiar?). Insufficient cant and it will not drift towards the back, but drift off the front(wrong angle).

A previous 'test' was to place a straight edge against the upper wheel and measure the distance the straight edge clears the top of the lower wheel. I suggest you do that. The clearance may be excessive in your case(an unusual occurrence). It should clear 1/4 to 3/8". If it is more than that, the cant needs to be DECREASED.

Then again it may be insufficient(that causes the blade to drift off the wheel)

I.E. I am not sure if yours tracks towards the middle and stays there, or it drifts completely off the wheel.

[Iwegian]

JPG...thank you for the info on "previous test" procedures. When I placed a straight edge against my upper wheel, it was flush with the top of my lower wheel. I then pushed the top of the upper wheel to remove all play,the offset between the two wheels was correct. SO.....I Removed and replaced the two bearings in the upper wheel. I haven't had a chance to see if that remedies my problem or not.
If my thinking is wrong, please correct me. My upper wheel is centered and true, so either the upper bearings or the axle are worn (or both). Worst case scenerio I will have to replace the pivot arm. After inspecting and measuring the axle, I don,t believe it is worn.Either way it is cheaper than replacing a wheel.
You were asking if the band continues creeping until it falls off the front. No it does not, it stops creeping and stays about centered.Thank you again for your input and information.