Bandsaw Blade oscillation

user-7617324 | Posted in Power Tools and Machinery on May 4, 2020 06:41am

Hi everyone – I am after some advice. I have bought a 2nd hand Scheppach bandsaw. It appears to be in good condition but I have put a brand new blade onto the machine and the blade moves back and forwards by about a 1/32″ – I am assuming it does it every revolution of the wheel. I have tried adjusting the pitch of the upper wheel which does alter the degree of oscillation but it doesn’t eliminate it. I am assuming I can alter, slightly, the bottom wheel because at the rear of the shaft are 4 adjusting bolts – 2 horizontal and 2 vertical – holding the shaft in position. But before I did anything I thought I’d seek some advice. Thanks everyone – Mick

Replies

muskokalayne | May 04, 2020 07:34am | #1
It sounds like you might need new bandsaw tires make sure that the upper and lower wheels are coplaner and if they are my bet is that it is the tires.
muskokalayne | May 04, 2020 08:32am | #2
Check out Michael Fortune’s video on bandsaw adjustment on the FWW website too - it’s excellent.
bilyo | May 04, 2020 10:06am | #3
The only thing I can think of that would cause back and forth oscillations like that is a warped blade. However, 1/32" is not very much and this might be the result of the way the blade was coiled in it's packaging. I would suggest that you check the tension and make sure it is properly set or, perhaps, increase the tension just a bit for a while. Also, make sure your guides are properly set. Use the blade that way for a while and see if it eventually straightens out. I recently put a blade on my saw that had been coiled up for a long time. It "wiggled" a lot for a while but the more I use it the better it gets.
gulfstar | May 04, 2020 11:37am | #4
Before you change the lower wheel angle and get into other problems, try to confirm that the blade is not the source of the oscillation. Disconect the motor, back off all guides and hand rotate the wheel to find the high or low point off the back of the blade. If it comes at each revolution of the wheel then it’s the wheel, if it comes at the same place on the blade every time the blade makes a full revolution, then it’s the blade.
geedubbee | May 05, 2020 01:42am | #5
A quick check to eliminate the blade is to remove it, lay it on its back on a flat surface and make sure that the back is touching all the way around. That is, looking for a bad weld or a damaged blade.
user-7617324 | May 05, 2020 07:05am | #6
Thanks for your advice - I'll see if I can isolate the problem using your tips. Its great being able to tap into this experience. Much appreciated. Happy woodworking - Mick
user-6893957 | May 05, 2020 11:57am | #7
Mick,

New here, so not sure this proper, but if you go to youtube, check-out the veto bandsaw clinic with Alex Snodgrass. The best I have ever seen.
gf
user-7617324 | May 22, 2020 05:37pm | #8
Thanks for the tip re Alex Snodgrass
user-211435 | May 23, 2020 01:30pm | #9
I've had the same problem a few times, almost always caused by the weld not being straight. 1/32" isn't that bad though.
rob_ss | May 24, 2020 06:03am | #10
I see this has been revived - I wonder, did you find the solution to the problem?

I generally take a reductionist approach to problem solving - remove one thing at a time until it goes away, starting with the easiest so:

1. Clean the blade and wheels - it is possible this is due to dust stuck to either.

2. Check the blade - is it kinked or damaged, is the weld straight. A new blade is always useful so buy one and test it.

3. Still going? pull the guides away from the blade.

4. Change the tension and tracking.

In the VERY unlikely event that you are sill having a problem with no guides, clean wheels and a new blade, you may have a distorted wheel or tyre. Bent wheels are unlikely , and very hard to test but if the tyres look ok, that may be where the problem lies.

A broken, binding or loose bearing in either wheel may be the cause, but should be noisy - spin the wheels sans blade to see what happens.

About the only thing it is almost certainly NOT is the lower wheel alignment. Unless sufficiently out of line to cause the blade to buckle, playing with that will get you into a world of hurt - leave it until there is nothing else to adjust and all else has failed. It is fixed for a good reason. Leave it alone.
user-7617324 | Jul 16, 2020 02:24am | #11
Hello everyone. I thought I would advise of the outcome.

I went through the process of elimination - thanks Rob SS. The issue turned out to be 2 slightly distorted tyres. I reshaped both ever so slightly by manually turning the wheels and scraping them. It still has a very, very slight oscillation but once I start a cut I think it is irrelevant. Its cutting really nicely now. I have ordered 2 new tyres. I suspect it had been sitting unused for a very long time with the blade under tension causing some compression of the tyres? Thanks again everyone - Mick