Bandsaw blade ‘fore / aft’ pulse

[SVB]

Re above two messages. I agree that the guides are a bit too far back from the blade edges. Side guides should be just shy of the bottom of the blade gullet. If the rear guide is not close ( say 0.5mm or a bit less) from the rear edge of the blade then no real guidance is being achieved. Probably your first adjustment.

My bandsaw will cut perfectly straight fence guided rips with no bearing support at all.

I’ve not adjusted the guides when this video was taken as I believe, as is said above, that the blade should run true and smooth without the guides when not in use. The guides are really just there to keep the blade on track when under load / cutting curves etc. The YT snoodgrass video shows the rear bearing just not making contact under no-load conditions so don’t think I should use this guide to hide the issue I have (even if I could which I’m not sure would work).

Simon

 

[delboy47]

The way the whole thing vibrates and shakes suggests to me something far more fundamental than just blade guides. As has been previously mentioned, a thorough check of wheels and bearings is in order I think.

 

[Alexam]

So Simon, have you tried moving all guides away from the blade and let it run. If so is the problem still there? Have you checked the wheels and tyres? Any findings? It would be good to find out if you have found the cause on your bandsaw, which may help others.

I saw this on an older thread elsewhere .......
I have a Rikon 18" bandsaw and talking to tech support they said if the blade is moving front to back you can adjust lower wheel (left to right) by loosening the side bolts on the end of the lower wheel shaft ( outside on right of saw). You have to loosen the top bolt just enough to release tension first. Tech support will send you the PDF instruction sheet if you need it.

 

[SVB]

So Simon, have you tried moving all guides away from the blade and let it run. If so is the problem still there? Have you checked the wheels and tyres? Any findings? It would be good to find out if you have found the cause on your bandsaw, which may help others.

I saw this on an older thread elsewhere .......
I have a Rikon 18" bandsaw and talking to tech support they said if the blade is moving front to back you can adjust lower wheel (left to right) by loosening the side bolts on the end of the lower wheel shaft ( outside on right of saw). You have to loosen the top bolt just enough to release tension first. Tech support will send you the PDF instruction sheet if you need it.

Thanks for all the comments and suggestions on this thread folks.

SWMBO / Kids are away saturday so golf in morning and bandsaw surgery in the afternoon. Will report back then.

Simon

 

[Alexam]

So? How's it going Simon.

It would be nice for those who have tried to help to hear if the problem has been solved and how you did it?

 

[Alexam]

Dont forget to let us all know if the problem is sorted.

 

[SVB]

Will do, I’ve not forgotten you’re all here!

Had a quick ‘wiggle’ of the wheels, both with tension on and removed and could feel no horrors in the bearings.

One issue that did the quick look did highlight was the top wheel tracking mechanism - the whole top wheel assemble essentially sits (rattle fit) in two crude vertical guides to allow vertical movement for tension to be applied but then a screw can be turned at the rear of the machine to push out the bottom of the upper wheel support assembly to ‘tip’ the wheel and therefore alter the tracking. It was much cruder / has a lot of free play in it - is this arrangement ‘normal’?

Simon

 

[CHJ]

One issue that did the quick look did highlight was the top wheel tracking mechanism - the whole top wheel assemble essentially sits (rattle fit) in two crude vertical guides to allow vertical movement for tension to be applied but then a screw can be turned at the rear of the machine to push out the bottom of the upper wheel support assembly to ‘tip’ the wheel and therefore alter the tracking. It was much cruder / has a lot of free play in it - is this arrangement ‘normal’?

Simon

Usual problem with lack of positive location in this mechanism is that if you have domed tyres and a touchy blade that you are trying to get to ride on the crown the slack in wheel assembley mounting flops from one side to the other throwing the blade off the crown and possibly off the wheel.

Can't see it giving you the fore-aft hunting you show, unless something else is pulling/pushing the blade back and forth across the surface of the wheel.

 

[Alexam]

It is normal on all bandsaws.

 

[Tervueren]

With the blade off have you tried spinning the wheels by hand, do they always stop in the same position, ie: mark the stationary wheel with a corresponding spot on the frame then check if it stops in the same place after spinning