Ramp to Print Surface in Raft Printing??

Share your successful printing settings with others here. If you have any question about the parameters or printing skills of some filament, please find here.
TheDude
Posts: 49
Joined: Tue Jul 17, 2018 2:45 am

Ramp to Print Surface in Raft Printing??

Postby TheDude » Sat Dec 08, 2018 6:53 pm

Has anyone else noticed in the new IM software, the print head seems to "ramp down" to the proper print height while printing rafts vs just descending to the proper layer height before extrusion starts?

Why is this happening??

crimsonyoshi
Posts: 119
Joined: Mon Sep 24, 2018 6:17 pm
Location: Manitoba, Canada

Re: Ramp to Print Surface in Raft Printing??

Postby crimsonyoshi » Mon Dec 10, 2018 8:41 pm

I think I understand what you're saying, but I can't say I'm seeing what you're describing. I haven't noticed any print height issues with the new firmware's. Which model of printer are you using? Have you tried contacting technical support?

User avatar
Vicky@Raise3D
Posts: 6973
Joined: Fri Mar 25, 2016 3:54 am

Re: Ramp to Print Surface in Raft Printing??

Postby Vicky@Raise3D » Tue Dec 11, 2018 12:42 am

Would you like to share the gcode and date file you have issue with? And some pictures can show the issue with us?

zemlin
Posts: 528
Joined: Sat Oct 21, 2017 2:02 pm

Re: Ramp to Print Surface in Raft Printing??

Postby zemlin » Tue Dec 11, 2018 3:52 am

Is this a problem, or just something different?

martialgeudin
Posts: 16
Joined: Wed Jan 02, 2019 10:00 am

Re: Ramp to Print Surface in Raft Printing??

Postby martialgeudin » Sun Mar 31, 2019 1:00 pm

I think I have the same issue, already damaged 2 nozzles, two buildtac surfaces and the bed plate is also scratched.
The raft is perfectly printed, the issue begins at the first layer. As it looks like the the Z-axis is not responding as it should or a g-code error.
Attachments
IMG_1072.JPG

martialgeudin
Posts: 16
Joined: Wed Jan 02, 2019 10:00 am

Re: Ramp to Print Surface in Raft Printing??

Postby martialgeudin » Sun Mar 31, 2019 7:46 pm

what I remarked at the building of the raft, is that it seems that the bed isn't parallel to the nozzle travelling plane. Is it possible that the machine bed is disturbed by a stepper motor not been synchronized, or desynchronized. If this isn't the issue, who can it be releveled and calibrated?

martialgeudin
Posts: 16
Joined: Wed Jan 02, 2019 10:00 am

Re: Ramp to Print Surface in Raft Printing??

Postby martialgeudin » Mon Apr 01, 2019 5:40 am

you should think that the problem solves it self after each layer is printed and a certain height. But this isn't the case, you can see that the nozzle is dragging into the already printed layers. It's a messy result. Is there an incremental error? I had the nozzle, heater ripped of, a fuse blown with a bed as a war zone. Please tell us what is going on. The printer did it well till now, it's a nightmare.
Attachments
IMG_1076.JPG

User avatar
Vicky@Raise3D
Posts: 6973
Joined: Fri Mar 25, 2016 3:54 am

Re: Ramp to Print Surface in Raft Printing??

Postby Vicky@Raise3D » Mon Apr 01, 2019 7:14 pm

Please check the bed levelness based on the document attached in the follow link:
https://support.raise3d.com/pro2-series ... ent_id=225

If the issue still exists after confirming the bed leveling has been adjusted properly, please open a support ticket to reach to our technicians at http://help.raise3d.com. If it is something related to Z axis, you may need to remove the bottom cover of the printer to do troubleshooting based on their guidance in case any unnecessary damage.

User avatar
Casale8
Posts: 248
Joined: Fri Oct 20, 2017 5:17 pm
Location: The Real Upstate New York

Re: Ramp to Print Surface in Raft Printing??

Postby Casale8 » Mon Apr 01, 2019 7:50 pm

TheDude wrote:Has anyone else noticed in the new IM software, the print head seems to "ramp down" to the proper print height while printing rafts vs just descending to the proper layer height before extrusion starts?

Why is this happening??

This has been the case for every print with Raft I've see with the printer. It starts moving a millisecond before it gets to its first raft layer height. Doesn't stop me from printing beautiful prints.
-SCC
“One man's "magic" is another man's engineering. "Supernatural" is a null word.” -R.A.Heinlein

martialgeudin
Posts: 16
Joined: Wed Jan 02, 2019 10:00 am

Re: Ramp to Print Surface in Raft Printing??

Postby martialgeudin » Mon Apr 01, 2019 8:36 pm

thanks Vicky,

even if the actual job isn't as perfect as I would like to have it, I will let it run to the end, so that I can messure the part on each side and let you know if there are differences. What I don't understand, is with the gantry method and the raft, even if the building plate should be out of level, after some build layers the build surface should be on level and all difference should be gone. So why is there a difference in height at different points on the raft and further build layer levels? And why in a same layer some zones are lower than others? Those zones are printed in the same direction next to each other, but with a z-hop in between. This is doing me thinking that somewhere there is an issue in the Z-axis or repositionning of the print height after the z-hop.

But I observed at the building levels that some layers ware very well printed and some layers further the same issue of dragging lines. Once the top surface of the object was finished and the walls get on to be printed. You could hear the nozzle scratching the last printed layer. So I believe in the z-hop function to find the issue or a stepper motor that jumps in a wrong position lower than what was last printed. What it caused, I don't know, maybe an update of the slicer or firmware. I also heared some cracking noises when the bed goes up or down. Why, also here I don't understand what came up suddenly after very good prints and big pieces.
So I have some doubts on the idea that the bed wouldn't be flat, as some layers are smooth and flat and others as shown in the pictures not.

I will give you a feedback, the machine has some hours to go before I can check the bed. Actually I am printing on a glass plate due to the destruction of the buildtak of a previous print of the same piece.

User avatar
Vicky@Raise3D
Posts: 6973
Joined: Fri Mar 25, 2016 3:54 am

Re: Ramp to Print Surface in Raft Printing??

Postby Vicky@Raise3D » Tue Apr 02, 2019 4:59 pm

From my understanding, Z hop won't re-position the nozzle height. It is only running based on what code tells the bed to rise or drop.

martialgeudin
Posts: 16
Joined: Wed Jan 02, 2019 10:00 am

Re: Ramp to Print Surface in Raft Printing??

Postby martialgeudin » Fri Apr 05, 2019 7:43 pm

the part is totally printed. The part has the following dimension: From left to the right: 190 mm, from top to bottom 225mm. The height is at 4 points different: on the picture at the left top: 56,40mm, at the right top 56,55mm, at the left bottom 56,51mm, at the right bottom 56,59 mm. this means that in diagonal from left top to right bottom there is 0,19 mm difference in level on the other diagonal 0,04mm. In straight line left from top to bottom 0,15mm, right from top to bottom 0,08mm is the level difference. When you analyze the picture at the bottom there where the differences are the greatest you can see irregular surface print at the opposite side at the top the surface looks very acceptable.
So what to do? Analyzing this the raft isn't helping to overcome this kind of bed level differences. It looks like to some height the difference is been taken to several layers before disappearing at the top. How to resolve this? Is it resolvable? And what are risks of calibrating it wrong?
Attachments
IMG_1079.JPG

crimsonyoshi
Posts: 119
Joined: Mon Sep 24, 2018 6:17 pm
Location: Manitoba, Canada

Re: Ramp to Print Surface in Raft Printing??

Postby crimsonyoshi » Wed Apr 17, 2019 9:15 pm

The bed shouldn't move along the z-axis until it's ready to go up a layer, or unless it's z-hopping. I can verify with my Pro2 Plus that Z-hop always returns the bed to the initial height after nozzle travel. (I've got a polycarbonate thread in this forum with pictures - which I need to update again now that I'm thinking about it). My Polycarbonate prints always come out fairly well, my problem is getting them to not warp, but that's unrelated to your question.

In terms of not calibrating the bed to be perfectly level, the worst you'll do is have a bit of nozzle drag on the model. The most damage I've done to my printer from that (via warping in my case) is breaking a coupler at the top back left of the printer, and ripping a nozzle right out of the hot end. It took a little bit of time to take the printer apart and replace the coupler, but the hot end swap was painless.

Now, when it comes to leveling the bed perfectly, you need some pretty fancy equipment to do that. There are digital levelers which read down to 0.001mm, but they can be fairly pricey online. Guaranteed if you leveled your bed to that level of precision, then if this keeps happening, you've taken bed levelness out of the equation.

As another long time user in this forum mentioned in another board's post, you also have to remember the print head will never perfectly print along an x-y plane of really small z-height. This is because the nozzle will sag due to gravity ever so slightly in the middle of the bed versus the edges due to the weight of the nozzle weighing on the rods. If your print is dead centre and uniform along the x-y coordinates, then the z-axis sag should also be uniform, but that will add to it not being perfect for your z-axis. I doubt it should be off by 0.2mm (z-axis) in terms of sag, but I don't know what metal composites are being used in the rods to even guess at hardness values of the metal.

The raft shouldn't fix a problem if the bed itself is not "perfectly" level. Flowrate will be uniform so the raft should also be uniform. The exception to this is if the bed is majorly out, causing the raft material to flow into a bunch of air before touching the bed (more than 0.2mm for a 0.2mm height setting).

martialgeudin
Posts: 16
Joined: Wed Jan 02, 2019 10:00 am

Re: Ramp to Print Surface in Raft Printing??

Postby martialgeudin » Sun Apr 28, 2019 6:39 pm

Thanks crimsonyoshi for your point of view, where I can accept the technical limits. I have a digital clock where -for I printed a support to fix it on the nozzle carrier. I didn't yet adjust the table, because of the related time to calibrate it and not making it worser than it was.

I noticed also that the raft is well printed, with the idea that this could help creating a flat surface, but as you mentionned the rods aren't big anough to support the carrier and not bending under the weight of it. So this is a problem to be solved by RAISE3D, consequences of a bigger rod is all what's around it and mounted on it that should be reconsidered. The idea of making the rods carry and transmitting the movements is excellent, but you need to consider also the weight to support. Maybe a double rod or a rectangular bar above the rods can help this bending to be reduced. Must be analyzed.
There is also a fact of bending of the bed coming from the heat that is created and making it to distort what was flat when cold and due to the heating points to change the shape. Notice also that the heating is one side, this creates tensions in the material and results in bending in opposit side of the heat.
The combination of those two cases causes different levels between the nozzel and the bed on different areas. So to be perfect this is an issue.

crimsonyoshi
Posts: 119
Joined: Mon Sep 24, 2018 6:17 pm
Location: Manitoba, Canada

Re: Ramp to Print Surface in Raft Printing??

Postby crimsonyoshi » Tue Apr 30, 2019 5:02 pm

Even with a double rod, you'd still have some sag. The weight would be distributed better, but the cut off here really is how much tolerance is enough. When you're printing down to 0.01mm layer height, then 0.01mm matters. Much lower than that and it shouldn't matter.

Let me link a thread for you as there's another very experienced user who's made modifications to his printer. I'm absolutely not suggesting you do this, as it would not only void the warranty, but also void support. I'm merely linking this thread as this other user deals with the sag and a few other "problems" he's found with how he wants to use his printer.

https://forum.raise3d.com/viewtopic.php?f=4&t=14683

And this one deals with nozzle heat (not quite bed heat that you're talking about, but it's neat none the less): https://forum.raise3d.com/viewtopic.php?f=18&t=10787

martialgeudin
Posts: 16
Joined: Wed Jan 02, 2019 10:00 am

Re: Ramp to Print Surface in Raft Printing??

Postby martialgeudin » Tue Apr 30, 2019 6:51 pm

Thanks for the ideas, but this is changing the whole machine. I could do this, but I think that it has to be possible to manage it in the software. Just need to know how to set the bed leveling points as reference points for the g-codes to be considerate and make the printed part at the correct size.

In the image you can see what the levels are of the bed. Maybe just adjusting the bed to this kind of deviations and the prints could be better.
I never will print lower layers than 0,05mm, for the steppers it is really the best. I have another printer and there printing layers at 0,1mm is very good, at 0,05 mm, it is possible but then you have other issues. Always the same accuracy is possible in very limited zones. Ones you print to far from the center you get problems, as adhesion and different layer heights.

The bed here in the picture tells us that one corner seems to be higher than the other corners. The bed leveling with the feeler is made on the left down corner at 0,2mm. When you see the results of measuring you can see that the right down corner gets at 0,16. This pushes the plastic away from the nozzle and taking it as a wave until there is enough space between the bed and the nozzle further to free space.

I will recheck the bed with my precision clock and try to regulate the corners to each other. In fact the clock is a digital one with usb-connector so if it could be coupled to the control part of the machine the software should manage this.
Attachments
IMG_1091.JPG

crimsonyoshi
Posts: 119
Joined: Mon Sep 24, 2018 6:17 pm
Location: Manitoba, Canada

Re: Ramp to Print Surface in Raft Printing??

Postby crimsonyoshi » Wed May 01, 2019 4:38 pm

Sounds like a good plan of attack for now. If you're still having trouble after doing a bed level, give tech support a call. You can also direct them to this forum thread so they can get a little more backstory.


Return to “Printing Settings”

Who is online

Users browsing this forum: No registered users and 2 guests