Firmware 1.18 released

gratefulfrog

I just upgraded from a very old version 1.0 from RepRapPro and I got a rather poor first print.. The linked photo shows the object printed previously with the old firmware and the new.

https://goo.gl/photos/7DXMoQSvDybQYKcD8

I used the same gcode file.

Any thoughts as to what could be wrong?

Thanks,
Bob

dc42

Assuming you allowed the print to complete, it looks to me that your Z acceleration and/or Z feed rate and/or Z jerk are set too high in config,g.

gratefulfrog

Sorry, I should have mentionef that I stopped the print because the filament jammed. So it never got to the full height.

I was thinking that the nozzle temp might be too high? But there's no reason why it would have changed, is there?

Thanks for your help!
Ciao,
Bob

dc42

It looks to me that the temperature is too high or the print is too fast or the print cooling is inadequate. Does your printer have a good print cooling fan? If not then you need to use a much lower print speed when printing tall thin towers like that, or e!se print 2 of those parts at once so that each layer gets time to cool while the corresponding layer on the other part is being printed.

gratefulfrog

Yes, I feel that the temp is too high, also. The print speed doesn't seem fast and the cooling fan is running.

The printer is a RepRapPro Huxely Duo, with a single head and a 0.3mm nozzle.

But what has changed because of the firmware update? Previously this same gcode file printed perfectly. I have done another test with the same result.

In your pm, you said that when I upgraded the firmware I should "Tune the bed and extruder heaters". What exactly does that mean? Could that be the problem?

gratefulfrog

I tried a new print of just a rectangular column 10x10mm.

It is PLA nozzle temp 195C, bed 57C. These are the settings I've been using for years.

As you can see in the image, at first it printed ok, but after about 15mm vertical, the glops start appearing and then finally the nozzle jammed.

Could it be that the extruder is extruding too much filament?

I am really at a loss as to how to debug this.

https://goo.gl/photos/UQt9gpSKS8P2gV2F9

Cheers,
Bob

dc42

Printing small rectangular columns is problematic on many 3D printers because a layer may not have time to cool properly before the next layer is printed on top of it. Things which help include:

Using a good print cooling fan. Make sure it to directed at the print just below and around the nozzle, not at the heater block.
Reducing print speed. Some slicers have a "Minimum layer time" parameter to facilitate this.
Printing 2 or more of them together, so that after a layer is printed on one of them it gets a chance ot cool while a layer is being printed on the other(s).

gratefulfrog

Thanks, I understand that but why did it work in the past with the previous firmware (V1.1) ?

Also, would that explain the nozzle jamming up ?

I had set the slic3r as:

enable fan if layer print time is below: 60 seconds
slow down if layer print time is below: 20 seconds
min print speed: 10mm/s

I don't see a "minimum layer time" setting in Slic3r.

Thanks for your help! I'll keep trying…
Ciao,
Bob

dc42

I can't think of any firmware change that would account for the difference, assuming that you are using basically the same config.g file with just the changes needed by the new firmware. Other possible reasons for the difference` include:

A change in the quality of the filament part way through the reel
Higher ambient temperature now than when you printed it before
Fan slowing down during the print, due to bearing wear and/or power supply voltage dropping
Z axis has developed a problem. I remember getting a print similar to yours where the print went wrong above a certain height. It turned out that the Z axis was binding and the print head was no longer moving up the full amount commanded.

gratefulfrog

Thank you again.

I tried another print at 190C for the nozzle and 55 for the bed as opposed 195 and 57 previously.

The result was better but still failed after about 52mm on the Z axis. At that point, I slowed the print speed to 80 then 60% but that did not change anything.

It's true that ambient temps is around 24C as opposed to 19C normally when I print.

Also, I am at the end of the filament roll, so that could be a factor.

There is no change in the noise generated by the fan, but I guess it could be slowing…

Last week, with the old firmware, I did a lot of printing and had absolutely no problems, except for the head crashing into the plate during Z probing. I printed 55m heigh objects, but larger than 10x10mm, 25x35mm in fact.

Here's a photo of today's test: https://goo.gl/photos/ZF9Ms48RkZx2ZLD66

Thanks,
Bob