Rear of bandsaw blades aren't meant to be square to the table?

matkinitice · 25 Jan 2021

See the images below.

I should add that the blade is bang on square left/right of the blade to the table, just not front to back.

Having just spent nearly an hour trying to align my table to the blade I concluded the only way to do this was to add washers to the underneath of the table, this seemed odd to me and the only thread I can find with a similar issue is linked below.

I too am cutting tenons - the reason I noticed this was having cut the shoulders, I then found the checks were not falling away. The top of the tenon was to my line - or as near as I would dare go, while the other side had a few mm extra to go.

I'm quite confused if this is the case as I don't really see how this helps, though the thread I've linked to says it's to help with thicker rips.

In practice I've had a bandsaw for a few years now and this really hasn't caught me out until now, so I'm after confirmation, an explanation or any guidance. I don't expect the bandsaw to cut to my marking out lines, I do expect to pare down with a chisel, however the small amount of difference top to bottom means the waste does not fall away without me lifting the piece and carefully pushing into the blade slightly.

https://forum.shopsmith.com/viewtopic.php?f=9&t=11912&sid=2e8695166191992d57b88ae7a637c4a9

Rorschach · 25 Jan 2021

Your wheels are not co-planer. Whether this bothers you depends on the work you are doing.

Ttrees · 26 Jan 2021

If the saw is running well...
Can you adjust your guidepost and the settings of the guides will stay the same.
If so, you've found you're reference.
The guidepost is probably non adjustable, so shimming or adjustment of the wheels could be necessary, either way the guide post is the reference which
should match your blade, and shim the table accordingly afterwards as you say.

On my machine there are nuts for that, and can also be used to flatten the table, as in get rid of any step where the blade slot is.

Tom

Terry - Somerset · 26 Jan 2021

Can you adjust the table to make it square to the back of the blade.

sometimewoodworker · 26 Jan 2021

Rorschach said:
Your wheels are not co-planer. Whether this bothers you depends on the work you are doing.

That is not correct and co-planer wheels, if the blade is running correctly, are irrelevant and even if you adjust the wheels it will make no difference.

The table is mounted badly or it was assembled to a badly made base, so if it needs shimming then that’s what it needs. I would first take the table off to see if the base supports were back to front or there is something you’ve missed.

matkinitice · 26 Jan 2021

Spot on - the table was the problem.

As far as I know, coplaner (coplanar?) wheels are not really a factor. Even if you go to this effort, as soon as you tweak the blade or adjust anything else you've got to start again. Of course you want the wheels to be somewhat in the same plane but that is beside the point.

I should add this is a Titan bandsaw - over three or so years old at this point so this may be down to the tool, newer models I believe have sorted some of the defects out (such as the fence) so this might not apply to everyone.

In the end I took four M8 washers (same as the image, just M8 - not M6) and put two washers under each bolt that connects the table to the saw. These were the two on the right, nearest the angle adjustment.

From my testing the day before, the problem only occurred once the table was locked down. When free this was spot on.

Once the bolts were fitted I re-attached the table and tested. Both directions are now square to the table, even after fully tightening the table adjuster. After following the Snodgrass setup this works great now, however my key takeweay from this is to check for square in both directions in the future.