Bandsaw Blade Tracking Adjustments Etc.

[caleb]

Q:A 25 degree twist seems unusually extreme to me. Are you tensioning the blade correctly?

A:I am doing it up to 1/2 which is the recommendation I have found in the manual and on the web. is that wrong?

Q:The back edge of all blades should 'ride' on the upper wheel about 1/4" from the back rim(1/8" from the back edge of the tire?)

A:the back of the blade rides on the upper wheel about 1/8 from the back side of the black rubber. if you want I can take pictures and post them.

Does your upper wheel wiggle?

Thanks for all your help.

Caleb.

[JPG]

Q:A 25 degree twist seems unusually extreme to me. Are you tensioning the blade correctly?

A:I am doing it up to 1/2 which is the recommendation I have found in the manual and on the web. is that wrong?

Q:The back edge of all blades should 'ride' on the upper wheel about 1/4" from the back rim(1/8" from the back edge of the tire?)

A:the back of the blade rides on the upper wheel about 1/8 from the back side of the black rubber. if you want I can take pictures and post them.

Does your upper wheel wiggle?

Thanks for all your help.

Caleb.

Define 'wiggle'. In/out as in warped? Sloppy on shaft? Arm moves?

Tension set 'properly'.

I am having a difficult time visualizing a 25 degree twist unless the blade is somehow bent.

[algale]

I assume you checked the obvious stuff: whether the blade guide blocks (upper and lower) are properly oriented? Those blocks have compound angles and if you have one or both guide blocks (in either the upper or lower guides) pointed pointed or turned in the wrong orientation, you will bend/turn the blade; in fact, Shopsmith demonstrates how to do this deliberately in one of the Sawdust sessions.

[caleb]

I would like to start by saying that you guys are awesome i didn't expect anyone to even to be reading this forum still let alone respond to my question.

Thank you so much.

algale I assume you checked the obvious stuff: whether the blade guide blocks (upper and lower) are properly oriented? Those blocks have compound angles and if you have one or both guide blocks (in either the upper or lower guides) pointed pointed or turned in the wrong orientation, you will bend/turn the blade; in fact, Shopsmith demonstrates how to do this deliberately in one of the Sawdust sessions.

Yeah I actually have them loosened at the moment as I didn't want them skewing what I was looking at.

Define 'wiggle'. In/out as in warped? Sloppy on shaft? Arm moves?

Tension set 'properly'.

I am having a difficult time visualizing a 25 degree twist unless the blade is somehow bent.

If I loosen off the blade and touch the wheel at the top bottom it rocks on the shaft a little I am guessing at this but about 1/8 or less. there is no slop in the fit of the bearing onto the shaft, just a slight back and forth.

In the picture it is not quite a 25 degrees but this is the only picture I have of
this until I get home from work.
I lay the allen across the blade so the angle could be seen.

[ATTACH]20589[/ATTACH]

for example.

if the axis of the wheel rotation is x and the axis of the axle is y then if you push the top of the wheel towards y the bottom of the wheel moves away from the bandsaw on the y axis.

did that help or just make it worse.


in response to the 25 degree angle imagine someone put the cool blocks in wrong and caused the blade to run on a compound angle. I don't know why I didn't just say that in the first place. sorry.

[algale]

Any chance you can post a few pics? I can't imagine how the blade could be skewing like that if the guide blocks are properly oriented or not touching the blade at all. Oops, I see you have the upper guide photo. How about a pic of the lower guide? Also a pic inside the cover showing where the blade is riding on the wheels....

[caleb]

I will have to take those later today. Maybe I can get home for lunch.

[caleb]

I have found a few sealed bearings that are 7x22x5 but they are in china.
I also found these. 7x22x6 what do you think
Bearings 7x22x6

These look nice for the price. http://www.vxb.com/page/bearings/PROD/627ZZ20

[caleb]

Here are some more pics,

I put the original single bearing back in for these pics
This is the Upper wheel so you can see where the blade sits


[ATTACH]20593[/ATTACH]

The next is the lower wheel

[ATTACH]20594[/ATTACH]

I am assuming this is what you meant?
[ATTACH]20596[/ATTACH]

Distance from lower wheel
I think it measure at 1/16

[ATTACH]20597[/ATTACH]

lower blade guide

[ATTACH]20598[/ATTACH]

[caleb]

After looking at the picture of the lower blade guide the only thing stopping the blade twisting more is the fact that it hits the cool block mount.

here is a clearer picture of the blade twist
[ATTACH]20599[/ATTACH]

This was not easy for me to describe. How would you guys have done it?

Caleb

[dusty]

The twist is definitely not right and in the next to last picture, it appears that the blade does not run between the cool blocks. That may be an optical illusion but if the blade travels where it appears to be, the blade would be forced to twist.

[ATTACH]20603[/ATTACH]

[ATTACH]20604[/ATTACH]

Are the ends of the two lower cool blocks parallel to one another. It sorta looks like the cool blocks are introducing the twist.