Shopsmith Forums

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Angle about 2 degrees

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Bevel about 1/16" = about 2.5 degrees


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Same 1/16"

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Notice the gap due to referencing the wider part of the tire.

About 1/16" again.

I could not get good pix showing a method similar to Dusty's without too much parallax error in the pix.

Using the blocks was a good method, but by assuming the tires are NOT beveled, the error introduced in the last pix was overlooked. Then there is that pesky parallax.

The degree numbers above are approximate and may be off a bit, hence the difference. I think it is actually between 1.5 and 2 degrees. The cant measurements indicate that.

This thread is a good example of discussions that would best be had if we could all sit around the same work bench and duke it out.

It almost seems as though we have all lost track of what the real problem was. That problem appears to have been resolved by changing the cant of the upper wheel thus causing the blade to track forward (more toward the center) on the upper wheel from where it had been. (Remember that the original symptom of his problem was the blade putting excessive pressure on the lower backup bearing (tracking to the rear). It is good that algale now has his bandsaw functioning as he believes it should.

Now we are looking at the performance characteristics of two other bandsaws; JPGs' and one of mine. The images that have been posted here, to support the current debate, seem to be evidence of two different but possibly related situations.

My photos were posted to show that the upper wheel is the same diameter front and back. Ignoring the tire, I believe the photos show that the wheels are 11" in diameter thus no taper. Assuming, of course, that the front and back rims are concentric.

JPGs' photo images are being presented to show that his upper wheel is beveled. I readily agree that it appears as though his is beveled. In fact, it appears that it is beveled in such a way that the blade has been tracking well forward of center and that the tendency would be to track forward off of the wheel.

I conclude this because of the debris on the tires. A part of the tire is clean (where the blade rides) and the rest is not. Observe, the part that is clean is forward of center while the debris has collected on the other half. If this observation is valid, it is consistent with JPGs' observation of a beveled wheel. His images seem to show the upper wheel leans forward thus tending to track the blade forward of center.

MY HYPOTHESIS: We are attempting to demonstrate two entirely different points of view and I believe two different sets of tire conditions.

QUESTION FOR JPG: Are your tires uniformly thick around the entire circumference on both sides?

My last post use placed prematurely. I went to the shop with a plan to take photos that would prove my point and what I may have most likely done is disprove it instead.

I now concede that there may be a bevel on the face of the aluminum lower wheel. I want to valid my observations using the other bandsaw but at the moment I am inclined to report that there is a 1/16" difference in the diameters of the wheels (front side vs back side).

I came to this conclusion not by measuring the diameters but by measuring the length of the spokes from the hub to the edge of the aluminum wheel (inside edge of the tire). The surface of the hub where it meets the spoke being the reference point.

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JPG: "Take my word for it, the wheels have a larger od at the back than at the 'front'. Yes it is slight!!! They are flat across that slanted face".

I did not take your word for it but you are correct. The diameters are not the same and there is a slight bevel.

All other observations remaining unchanged, this bevel would tend to move the blade off of the wheel on the front side. Thus the puzzle remains unresolved.

Take another look at the debris on 'my' tire. The light 'line' was created by using a 1/4" blade almost exclusively(by the PO).

The back of the blade was riding about 1/8" from the back edge of the tire. The area in front of that light 'line' has not been subjected to a blade running over it.

You are correct, IF the wheels were co-planer, the blade would tend to run off the narrow side.

That is a reason for the cant. By tilting the wheel(top towards the 'inside') the front(teeth) of the blade is pressed upward and backward. This is possible(the blade cannot stretch) because the lower wheel also has the bevel.

The amount of cant needs to be twice the bevel angle since the blade rides on the bottom of the bottom wheel and the top of the top wheel.(the angle from 'horizontal' is in opposite directions)

This also results in the blade deviating from vertical(the bottom leads the top which creates fits for folks cutting thick jig saw puzzles:D).

The cant is slightly more than that so as to impart that rearward force that presses the back of the blade against the rear and lower front tracking bearings. Too little cant will cause the blade to run off the front. Too much cant and the rearward force is excessive.

All this is consistent with what Algale experienced except his assertion that the upper wheel has reverse cant after getting it to track properly. THAT is the present mystery.

Not sure the hub to rim measurements are informative other than the front/back outer diameter of the rim differ. The back rim has that lip. I think that lip is there to prevent all that stuff above from pushing the tire off the back of the wheel.

Yes this has taken a slight drift off the original 'purpose' of the thread, but hopefully all that are reading the later posts will gain a better understanding of this unusual design.(assuming Dusty and I are not the only ones reading)

I'm still reading. The proof is in the pudding and it does indeed look like those wheels are beveled, so my apologies JPG.


I've been unable to get back to my band saw for the last couple of days. But after Thanksgiving I will take some more careful measurements and do some more test cuts to see if the problem is resolved. I will also mount the 5/8 bladeto my new-to-me older cast iron bandsaw and see what is happening with it.


If others have a 5/8 blade and can measure wheel cant with it mounted and tensioned, that would be interesting too.

algale wrote:I'm still reading. The proof is in the pudding and it does indeed look like those wheels are beveled, so my apologies JPG.


I've been unable to get back to my band saw for the last couple of days. But after Thanksgiving I will take some more careful measurements and do some more test cuts to see if the problem is resolved. I will also mount the 5/8 bladeto my new-to-me older cast iron bandsaw and see what is happening with it.


If others have a 5/8 blade and can measure wheel cant with it mounted and tensioned, that would be interesting too.

Not sure what else to measure after your input regarding cant being correct with 1/8" space between back of blade and back edge of tire per CS.

Seems to me that nails it! The cant angle will affect that measurement. All the rest that has been tossed around is secondary(straight edges against wheels etc.) If the cant is excessive, that will be greater than 1/8". If cant is insufficient, that will be less than 1/8".

Now the back force will be greater with a wider blade for a given cant. The wheel is pressing against the tooth edge of the blade. Wider blade = greater 'leverage'? Assuming a stable axle etc..

Please verify that reverse cant. Straight edge against upper wheel will do. Lay it just clear of the hub.

I predict tis not so. Straight edge will clear bottom of lower wheel more than at top of lower wheel.