I recently bought a Rikon 10-326 (14") bandsaw, mostly for re-sawing wood.

I having been cutting Sapele veneer for a project.  A heck of a lot of veneer actually, and almost finished, and its been giving pretty good results.  But suddenly I can't cut straight.

The blade is pulling towards the fence.   I was using two featherboards, one high, one low, to keep the board against the fence, but for test cut shown below, I just held the piece of scrap against the fence for a test cut.   You can see how within a few inches, the blade pulls towards the fence.   I now have marks on the fence from where the blade has contacted the fence.   Cut is pretty straight, top to bottom.

Many boards I could cut with the guide rollers just above the fence, but the last board was a bit taller and I raised the upper guides another inch.  After that adjustment is when the problems started.  (sorry, should have stood back another foot so I would get the guide rollers in the photo)

I increased the blade tension a bit.   I checked the fence angle, and did have to adjust it a bit to get it parallel to where the bandsaw wants to cut.   Tried lowering the upper rollers an inch again.   Tightened up the clearance on the upper guide rollers.  Did not help much.

I don't know what to check or adjust next.    Any thoughts ?

Edit:  I did notice that recently the cut had a higher propensity to smoke, so that tells me somethings are fighting.  So maybe the answer is the angle of the fence ?

Most of time when it starts to go or against fence is DULL blade.  You will be amazed how quickly the blade gets dull on the band saw.
Try with new saw blade and I'm assure it will be straight cut again

Most of time when it starts to go or against fence is DULL blade.  You will be amazed how quickly the blade gets dull on the band saw.
Try with new saw blade and I'm assure it will be straight cut again

Thank you.  I was wondering about that.

Dang.   Veneer for this stack of sheets is the majority of what I have cut with this blade.  It does add up to quite a few cuts, however.  The stack only needs to get a bit higher.  I might have to spring for a carbide tipped blade.

If the blade wants to wander on you and you're getting burning on the cut, I would check the tension.

The tension pointer is just a bit over the manufacturer's indication for this 5/8" blade.   I know these pointers are not the most accurate, but pushing on the blade with maybe a few pounds force will deflect it about 3/16".

This happens when the blade dulls.  I spent 3 days troubleshooting the setup before I remembered I had cut through a nail the day before it started drifting.

The easy way to sharpen a bandsaw blade is to use a dremel and a diamond disc, with a jig to maintain the right angle.

Thanks to all for the input.

I tried sharpening the blade, using a round file that matched the diameter of the gullet side of the blade.  Must have been pretty cheap files, I smoothed two of them trying to sharpen the blade.
My 3.5" piece of scrap cut pretty well, but my 6.5" tall workpiece still showed a fair amount of blade movement.  I don't think I did a very good job at sharpening the blade.   But that seems to show blade sharpness was the root problem.

The carbide tipped blade is on order.

My bandsaw came with a HSS blade and I spent ages trying to get a decent cut but just couldn't, it baffled me what I was doing wrong. I bought a TCT resaw blade, and suddenly I was getting beautiful straight and thin slices. Turned out the stock blade was just junk. I've been using that blade for the last 2 years straight and couldn't even begin to guess how much it's done. it's lasted so long it's possibly not worth sending off to be re-sharpened when that day comes and just getting a replacement would still be cost effective given the massive amount of use you get out of a good blade.

I later saw a lot of similar posts on the forums, so it's a common theme it seems.