From what I can make out, ...
On my machine (which has flat tires)
a narrow width blade will run without any trouble, but a wider blade especially if it's of thin gauge will be troublesome,
And a heavier gauge wider blade will run better and make drift adjustment , which if you like to keep the mitre slot parallel and adjust trunnion bolts instead very apparent.
Can't say for sure if the thicker guage blade will work here on crowned tires,. But I would definitely think worth a shot should one be thinking of filing slots.
Would have saved me doing so anyway.
Not suggesting you go wider, that sounds the honest comfortable limit of blade width to me,
Just reckoning the thicker gauge will likely have more set.
Probably will just hide the real cause though, and should you want to use the thinner gauge 19mm blade you have now, then it's worth inspecting the machine.
Can't be much more at play,
Whether the tires are positioned on the wheels the same or could one have moved, making the crown uneven could be another factor.
Should the machine not sit well no matter what you do,
I'd certainly be leveling the machine up, and checking everything, if the machine happens to be a bit wobbly/tippy
After failing to get my machine level after a week or two, using two plumb lines,
I made these four wee blocks to get things level.
They don't need be magnetic, bit of masking tape would do fine.
(my machine is a bit higgildy piggildy in regards to flatness, so saves finding good spots, plus I like where below is positioned)
Then you can go in for a cuppa, cuz those lines need settling/streching.
Your eyes can get fooled, and these to me seems as accurate as you can get if you have a spot lamp to check.
Still rocks about, but at least a sure method of it being suitable to check other things.
Yes I did buy fancy woven plumb line, but fishing line would do when used as such with the lighting favouring things.
Just two bits of scrap, some rubber/hair bands, four blocks w/tape
fishing line and a few nuts or whatever would do.
After being leveled, one could try these tests for the top wheel.
Wheel protrusion from cabinet, and left/right carriage adjustment should your machine have either.
The string sits on the wheel nuts,
If all works out, level machine, top wheel aligned,
east/west jacking screws matches the top wheel, and also motor pulley,
gradual tightening of the drive belt without blade, shouldn't need be tight though!
Tires OK,
then I would be looking to see whether either wheel can move,
On my machine this not apparent, but with patience can be noticeable.
My top makes strange noises,
A consistent slight knocking sound when hand turned without a blade installed,
But when slowing down after use, and also when hand turning afterwards some groaning is slightly apparent, but no noticeable knocking.
Even though the SKF bearings are relatively new, hope they are toasted on the top wheel, can possibly do some tests with the old ones, should a pair be OK for the meanwhile.
Must take belt off t'other wheel to check the ones on bottom wheel too.
Hopefully they are just damaged from the lower wheel being misaligned with the un-tiltable top wheel, because of that guidepost which is made right now,
and it's not the wheel hub!.
Think I may have some 30mm stock to make another shaft, and if I don't I can spray weld it.
Hope to use some thin gauge blades again sometime, as they are nice and scrimpy with the material.
Hope this helps in some way or another, even if food for thought regarding possible wear.
I've only made a component for my trunnion, had made a lash up before that which didn't work well, and eager to see if the trunnion plate is gonna be parallel, as squareness to the blade is relying on the edge of that plate under the trunninon.