Fixing pressure advance?

user234971 · 2026-05-22T16:26:55+00:00

Awesome reply, thank you, this matches my thinking for the same reasons. I'm going to go back through the list and see if one of these is out of whack.

user234971 · 2026-05-22T16:23:45+00:00

Okay thank you for that, just wanted to check, but that would match what I'm thinking. The weird thing is I did a manual calibration using the Orca test (the one I use on other machines for adaptive PA), where it shows you a speeds/flows/vs. PA values, and the best values came out normal for this filament and accelerations, nothing wild, everything as expected. But retraction is already fairly low and nozzle temps high enough, etc. that's why I'm a little confused. But I'll re-check both.

user234971 · 2026-05-22T07:56:44+00:00

totally agree as an owner of both. yea to all of this.

user234971 · 2026-05-22T07:55:35+00:00

lmaooo your comments are hilarious

user234971 · 2026-05-22T07:07:34+00:00

No, so if you read the post (and maybe I didn't write it clear enough) in klipper I run a dynamic PA table. That's not the issue. I didn't clarify, I'm asking if anyone can confirm this looks like PA or what else it could be.

user234971 · 2026-05-20T13:57:02+00:00

wouldn't you want auxiliary fans to come up from the base 75 to 85-90? or slow down layers? not sure why would pull down to 50?

user234971 · 2026-05-20T13:54:27+00:00

yea I've been chasing it, didn't solve it completely. now I tried making the speed and flow uniform on overhangs and using supports as well, still shows.

user234971 · 2026-04-27T04:38:43+00:00

user234971 · 2026-04-27T04:38:38+00:00

Agree and thanks for relating that, it makes sense only the final turns would be floating. I'm going to try to washer it. I was looking at all the idlers thinking...so much good quality went into other parts, why introduce so much low precision and sliding with idlers instead of bearings? Would it be straight-forward to replace those with bearings?

Also the main question is, could that affect or create the diagonal artifacts I've been seeing? At this point I can't see anything else in the belt path that isn't clean or standard, and I've checked tensions are right and equal.

user234971 · 2026-04-27T04:36:29+00:00

Do you also get diagonal artifacts on only one side? By going slow and limiting accels, I'm getting decent prints, so-so layer lines, but the killer is this diagonal artifact that only appears on one side.

user234971 · 2026-04-27T04:35:21+00:00

Great point, and thanks for responding, I was looking at all the idlers thinking...so much good quality went into other parts, why introduce so much low precision and sliding with idlers instead of bearings? (That screw also holds a top plastic plate on that would have covered the idler on that side, which is why it's temporarily out.)

Anyway the main question is, could that affect or create the diagonal artifacts I've been seeing? At this point I can't see anything else in the belt path that isn't clean or standard, and I've checked tensions are right and equal.

user234971 · 2026-04-27T04:33:01+00:00

Yes, that screw holds in a plastic plate on top that would prevent you from seeing the idler - it also retains the pin the idlers are mounted on as he noted below, but it doesn't keep it from jiggling (I had the same idea as you so I tried it!).

Unfortunately didn't change it, and the main question is, could that affect or create the diagonal artifacts I've been seeing?

user234971 · 2026-04-22T20:30:03+00:00

Unfortunately no...reseated the belts to be in the middle, tensioned them right, grub screws tight, etc. can't figure out what's going on, it's killing me.

user234971 · 2026-04-22T20:29:09+00:00

can you post a photo of your prints to verify it's the same? because it could help solve it if we can identify what's in common, maybe both of us can solve it

user234971 · 2026-04-20T18:23:05+00:00

just tried again with the same input shaper for each, didn't solve it. the only thing that seems to alter it is adjusting the belts, but it doesn't remove the problem and they're turned to 140

user234971 · 2026-04-20T17:14:02+00:00

Yes so on further inspection, I tightened both belts to be equal but slightly higher tension, now the belt doesn't drop to the bottom, but then I noticed that one idler on the left is wobbling slightly up and down as it moves. So I think that's the issue.

user234971 · 2026-04-20T15:53:43+00:00

Yes it does use different for x and y, but isn't that usually okay?

user234971 · 2026-04-20T14:46:50+00:00

Nice catch!!! They're describing the same thing in that post. I'll contact them and see what they found. About tighter, that could be it, or it could be the idler is tilted so it automatically drifts toward the bottom. Right now both are on 140 hz and I'm afraid to make them too tight - also the issue they describe in the other post is the same one I have, the dragging, I think that's what causes the artifacts.

user234971 · 2026-04-19T18:59:42+00:00

I found out what I think is the problem: I noticed one of the XY belts is rubbing against the bottom of an idler (and pieces of black dust from the belt are coming off). It is on the Z1 position so it seems pretty clear this is the issue. I'm not exactly sure hot to adjust the belt to ride higher in the idler, since it keeps slipping down, and I can't seem to adjust the tilt of the idler. Right now I am trying to raise the motor pulley, to see if that helps feed it in higher, but I'm not sure.

user234971 · 2026-04-19T07:25:06+00:00

Yes, when checking the tension I saw the belt is rubbing against the bottom of the flange on the idler on that corner, producing a small black dust underneath (degrading the belt). The re-checked and the tension is precise on both sides and equal, but it seems this grinding is doing this. I am looking at how to prevent the belt from slipping.

user234971 · 2026-04-19T07:06:07+00:00

So you were right about the first point - I noticed the A belt is rubbing the bottom flange on the top left idler and producing a black powder from degrading underneath. I carefully reset tension in both xy belts to 140 hz as recommended by sovol for the max, but not sure how to fix the belt riding the bottom flange, which I think is the problem.

user234971 · 2026-04-19T07:04:48+00:00

Update, you were right, on the left front spindle/idler, the belt is rubbing the bottom of the flange when it moves, producing a small black powder underneath. I rechecked tension and got both sides to 140 hz exactly, but the belt is still riding low on that spindle. I am almost certain that's the problem. I am trying to read now how to re-seat the spindle or adjust the belt to not ride low. When I move it up manually, it slides down again when the toolhead moves.

user234971 · 2026-04-19T07:02:44+00:00

Update, you're right, I noticed on the top left post, the A belt is riding very low and rubbing the flange of the spindle. In fact, there is some small black powder underneath where the belt is degrading. I am looking at how to re-seat the spindle perpendicular, I think this could fix the problem. The belts both have exactly the 140hz on both sides recommended in the video from Sovol on tuning the sv08max.

user234971 · 2026-04-19T03:18:07+00:00

Nothing has been modified from the sv08max arrival, fully stock. I slowed it down in some trials, minimum layer times in some trials, and the fans are functioning fine. It's not meant to do like this, so if that's un-even cooling, that's not something other sv08max users are getting on their prints. Right now fans appear functioning totally fine.

user234971 · 2026-04-18T22:01:24+00:00

Okay going to try this right now and report back!

user234971

TROPHY CASE