Topic: Squeezed bottom layers
Is there any possiblity to remove the "brim" at the bottom. I don't have any in my settings but if you look at my print my first layers always get wider than the rest.
Maybe an adjustment of the flow-rate or z-offset?
Re: Squeezed bottom layers
I don't know the setting in Slic3r but skeinforge has a setting for first layer flow and speed. I play with that but be careful going to far and you'll lose your bond. You also look like you have a retraction problem.
3 2013-03-12 20:19:22 (edited by digiprint 2013-03-12 20:20:10)
Re: Squeezed bottom layers
Yes, I'm using Slic3r.
Sorry for the question that may be a stupid one. Where or how do you recognize a retraction-problem?
Re: Squeezed bottom layers
On the picture that ends in 559, the filament lines that go across the middle I'm assuming were not inentional, so that shows that there's filament coming out when it's not supposed to. On that print it also looks like you're extruding too much material (flow rate) because of the way that the nozzle is dragging through the filament creating a path through that looks like the nozzle is plowing more than laying down a clean layer. If you're being really nitpicky you can tell by the halo brim that on the left hand side the filament is wider than on the right hand side, which is showing that you're likely higher there than on the right hand side so your bed is slightly out of level. All these are minor things but I would start with adjusting your flow rate using Ian's blog method. Then level your bed as well as you can with a paper or indicator if you're so inclined. Then adjust your z endstop so you get the z height that you want (because you're changing your level). Then worry about changing the first layer flow to get the balance between good adhesion to the bed and not too much squeeze as you call it. Then do a search on retraction and play with those settings, sometimes you have to change it per filament roll or adjust the temperature per filament roll so you don't get as much oozing out.
It sounds like a lot but you're close to getting really good looking prints. Your banding doesn't look nearly as bad as some have here.
5 2013-03-12 20:40:19 (edited by jefferysanders 2013-03-12 20:52:33)
Re: Squeezed bottom layers
I would say that print looks pretty good though, your settings can't be to far from the quality prints we all seek. Adjust your z-offset for sure. The first layers should not so squished that you end up with a brim, I personally squish the heck out of mine and just make the changes I need to the file itself. I bet you could also use the flowrate slider and just turn down output temporarily and just under-extrude the first layers for a similar result. Also, make sure not to use more bed heat than needed that can cause very mild distortions. Another way it could be done is by adding a very small chamfer at the bottom of your part...this is probably not ideal though, but still might also do the trick as it does for me if I need. Retraction issues normally show up as tiny strings all over the internals. (those 2 lines inside your box could just mean you need to increase the retraction rate I'm set to 90mm/s for .20mm files w a .20 lift (do use Anti-backlash nut with lift on, otherwise you might end up with delamination). Like Cmetzel very accurately stated...definitely calibrate your flow-rate in accordance to Ian's Blog as well as take notice to the skirts varied width (that definitely indicates your bed is slightly off level...which will cause everything else to be jacked up) if you have not already...that will ensure you are extruding near to the correct amount. (I followed his guide, set the corrected values in my firmware, then set all of the extrusion sections to auto or 0)
- wire10ga
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Re: Squeezed bottom layers
Looks like I need to do this adjustment as well. Thanks for the tips.
SD2 - Glass Bed, Fans on PCB and Y motor, Custom enclosure
Slicer - Simplify3D
Slicer - Simplify3D
7 2013-03-12 21:05:19 (edited by digiprint 2013-03-12 21:05:41)
Re: Squeezed bottom layers
Which way is the better: adjust the z-offset (additional = zero) and set the height of the first layer in the slic3r settings or to use the z-screw to set the height manually.
Re: Squeezed bottom layers
I set my z height to be light pressure on a single piece of paper, then have my first layer print at .9 flow and feed. This gives me a little more squeeze but I like having the first layer bottom flat and smooth for the best adhesion, and I knock off the high edge with a detail file and you can't tell it was ever there.
Re: Squeezed bottom layers
I adjusted the flow-rate right now.
The skirt keeps looking the same as before. My bed is leveled and the y-axis is also leveled.
is it possible that the printer doesn't extrude the right amount right from the beginning? (look at the start of the skirt in front of the square)
Re: Squeezed bottom layers
The whole purpose of the halo is to get filament flowing before it starts on your print. It's normal for it not to be there on the beginning of the halo.