gnt2003

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  • in reply to: MadDavo's P38 #34161
    gnt2003gnt2003
    Participant

    Nice colour scheme 🙂
    Hope you get it dialed in for the second flight, it’s fun to fly when the nerves stop!
    Great repair job too.

    in reply to: P-38 Control Throws #32717
    gnt2003gnt2003
    Participant

    Thanks I’d forgotten I’d posted here as well as the RC Groups thread. Someone there pointed me in the same direction! I ended up going without significant differential aileron because I’m using a y-lead having run out of channels on my 9X. But it still flew brilliantly. Only done two flights so have not been able to assess flap-pitch interaction.

    in reply to: Anyone tried a Creality CR-10? #32440
    gnt2003gnt2003
    Participant

    My pics didn’t attach!

    in reply to: Anyone tried a Creality CR-10? #32439
    gnt2003gnt2003
    Participant

    I’m glad it sounds like you are on the right track Travis. Perhaps not all CR-10 extruders are made equal, with dodgy stepper motor voltages, and possible issues with the guide bearings?
    I’ve just checked our extruder stepper motor and it was the hottest of the motors running at about 42C – albeit with quite fierce retract settings. There is a fair bit of wear on the feed in hole to the extruder clamp too. I checked the amount of tension in the filament, just from the stock spool and it is surprising. We will be printing out a roller bearing spool holder for sure, and the cable feed clamp and see if a freer rolling spool decreases the temp on the extruder motor. I can see that back tension on the filament would not be good for print consistency.
    We have finally fitted our PEI sheet to a piece of glass and I can tell you it’s a superb mod, even with a decidedly iffy ‘stick to glass’ (double sided 3M sheet) process that has resulted in one corner of the bed not being especially level, and two holes in it from smashing a heated nozzle into it during the bed levelling (don’t ask). Best bed adhesion we have had yet for the nosecone of the P-38 – all cannons stuck perfectly, and as long as they come unstuck when the bed cools, we will not be going back to glass and hairspray.

    in reply to: P-38 printing question #32388
    gnt2003gnt2003
    Participant

    Cat: https://www.thingiverse.com/thing:2643326
    Calibration cube: https://www.thingiverse.com/thing:1278865
    Temp tower (inc bridging): https://www.thingiverse.com/thing:2318636

    And have you read this:

    FAQ

    • This reply was modified 2 years, 4 months ago by gnt2003gnt2003.
    gnt2003gnt2003
    Participant

    Re: GnT – it is both that definition as well as the first initial of me and my wife’s names. I never thought of the 2003 as a time before! It’s the year we got the email address. Any time after midday is Gin & Tonic time 🙂
    Thanks for the info on PETG and the enclosure. I’m watching for reports of Thoemse’s maiden and will then be contemplating a serious upgrade of the CR-10 bed insulation and hotend to work in the hotter plastics. I have some Polymax PC to try which will test bed adhesion and temp stability…PETG is the ‘fall-back’.

    in reply to: P-38 printing question #32377
    gnt2003gnt2003
    Participant

    Maybe I can post a pretend .FFF file? Rename as .rar and extract…no I cannot, wow this forum is frustrating!

    in reply to: P-38 printing question #32364
    gnt2003gnt2003
    Participant

    Ok – that basically confirms you are going to have to dial in your printer on test objects and sort it out before expecting to print good 3DLabPrint parts I’m afraid. There’s lots of tutorials on youtube etc. Here are the temp tower (which is a lot of G-code editing in CURA to get the different layer temps!), Cat, calibration cube we used, together with a pic of the cat and quick stringing tower. The Cat was printed out-of-the-box like that with our CR10, but I think we used the supplied G-code that came with our CR-10.
    I’m providing these mainly to show that we had this sort of quality *BEFORE* we started playing with the 3DLabPrint parts and complex slicer settings and we still struggled to absolutely nail the print settings.
    You *might* be able to short cut that process, but only I think if you get a genuine Prusia and have a bit of luck. For those of us with aftermarket bowden printers, we have a long road of tinkering.

    Now specifically, I don’t like the black gunk on the bottom of the cat. What’s that from? And have you tried different filaments? Get some e-sun PLA or other quality filament, to eliminate that as a problem.

    in reply to: P-38 printing question #32362
    gnt2003gnt2003
    Participant

    Not sure I can post STLs

    • This reply was modified 2 years, 4 months ago by gnt2003gnt2003.
    in reply to: P-38 printing question #32359
    gnt2003gnt2003
    Participant

    Ok – that basically confirms you are going to have to dial in your printer on test objects and sort it out before expecting to print good 3DLabPrint parts I’m afraid. There’s lots of tutorials on youtube etc. Here are the temp tower (which is a lot of G-code editing in CURA to get the different layer temps!), Cat, calibration cube we used, together with a pic of the cat and quick stringing tower. The Cat was printed out-of-the-box like that with our CR10, but I think we used the supplied G-code that came with our CR-10.
    I’m providing these mainly to show that we had this sort of quality (the cat) *BEFORE* we started playing with the 3DLabPrint parts and complex slicer settings and we still struggled to absolutely nail the print settings.
    You *might* be able to short cut that process, but only I think if you get a genuine Prusia and have a bit of luck. For those of us with aftermarket bowden printers, we have a long road of tinkering.

    Now specifically, I don’t like the black gunk on the bottom of the cat. What’s that from? And have you tried different filaments? Get some e-sun PLA or other quality filament, to eliminate that as a problem.

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    in reply to: P-38 printing question #32292
    gnt2003gnt2003
    Participant

    Yeah, but they slice it for a properly setup stock Prusia i3 with a direct extruder. Your Bowden totally throws it off, and the clone element adds another wild card. A fellow flyer has a Prusia clone – may also be a Geeetech – but with a direct extruder and he spent hundreds of hours getting it sorted with all the control provided by Simplify3D. I fear that without the control of a slicer, you are going to be really struggling. You are right though, using the G-codes should allow you to print the sophistication they built into the slicing – but only if you can tune the critical settings to what your printer needs, and only if your printer is completely setup properly.
    If you print something like the test cat with CURA, does it come out flawless?

    I’ve just spent a good hour in S3D looking at the default profile for the Geeetech S3D and compared it to the Prusia i3 and some of the settings the 3DLabPrint folk use.
    Prusia default: Temp 215, Nozzle = 0.4, Extrusion Multiplier = 0.9, Extrusion Width = 0.45mm, Retraction Distance = 1.5mm, Extra Restart Distance= 0mm, Retraction Speed = 30 mm/s, No coast or wipe, Print speed = 40 mm/sec, Outline underspeed = 100%, X/Y speed = 80 mm/s, Z speed = 16.7 mm/s.
    Geeetech default:Temp:190, Nozzle = 0.3, Extrusion Multiplier = 0.9, Extrusion Width = 0.36mm, Retraction Distance = 1.0mm, Extra Restart Distance= 0mm, Retraction Speed = 30 mm/s, No coast or wipe, Print speed 60 mm/sec, Outline underspeed = 50%, X/Y speed = 80 mm/s, Z speed = 16.7 mm/s.
    3DLabs Profile: Temp 230, Nozzle = 0.4 , Extrusion Multiplier = 1.02, Extrusion Width = 0.42mm, Retraction Distance = 1.5mm, Extra Restart Distance= 0.12 Retraction Speed = 30 mm/s, Coast = 0.2, Wipe = 5mm, Print speed = 60mm/s, Outline underspeed = 70%, X/Y speed =150 mm/s, 16.7 mm/s, Z speed = 16.7 mm/s.
    There’s big differences between the Prusia/3DLabs nozzle diameter and hence extrusion width and in theory at least, they ended up extruding a fair bit more plastic than the defaults. That’s where weighing parts is important – along with your e-steps calibration. I would suggest you should slow your printing down too (overall and the outline) – but keep your Bowden retract settings. And finally, it looks like the Geetech does run hot, so I’d cool it down by 15 to 20 degrees from the stock G-code temp – which will pretty significantly affect your retract settings! It’s tempting to say this is why a good slicer is required…

    I think that’s the best I can do help wise – I hope you get it sorted, it must be really frustrating.

    in reply to: P-38 printing question #32281
    gnt2003gnt2003
    Participant

    Modified g-codes, or sliced with CURA?
    I did most of my printing at 220, but I think you are running hot. You could see how it goes at 215 or even 210. In the 3DLabs files, the ailerons are printed with different settings (slower and smaller layer height I believe, I’ll check tonight). I think the reason you are getting variations in different places is because of where CURA is putting the retract points. But that is not the reason for the actual defects – there’s still something quite wrong and I’m not convinced it’s just the slicer.

    I suggest you ask support if they can slice their parts for you using your retract settings to completely eliminate the slicer as a problem but beyond that I’m out of ideas atm. Maybe someone else can chime in.

    in reply to: P-38 printing question #32068
    gnt2003gnt2003
    Participant

    Weigh it! Accurately. It will tell you a lot. Both your problems would be explained by underextrusion, but an underweight part would confirm that. The trailing edge on these parts is really thin and overall underextrusion may show there with small holes. The manual says this part should weigh 54g.
    The outer perimeter of the wing is likely to be sliced as one run (it doesn’t have to be though). When I slice the part in Simplify3D your holes seem to be appearing at the end of a longish travel move just prior to the beginning of the internal structure that joins to the perimeter wall. So I think you don’t have sufficient plastic in the nozzle at that point, but the slicer thinks you do. I’d be backing off the retract settings to retract less filament, especially if you don’t have bad stringing and these antler/caterpillar like blobs.

    Pictures are really helpful BTW 🙂

    The stringing tower won’t necessarily show some of the problems because its so small. Try placing two towers about 8cm apart on the bed and print them. That will give long enough a travel move for problems to start showing up.

    Also attached is a couple of Simplify3D views in g-code preview showing how you can really visualise exactly what the g-codes will be commanding the printer to do. That’s great at trying to understand what the printer was doing when you weren’t watching (and tells you what time to get back and check on the next print!). It’s coloured by movement speed (using the stock 3DLabs settings, not tuned for a Bowden printer, sorry, the retracts are shown faster than they would be on ours!) so travel moves are fast in red, retracts are a bit slower. You will note the gaps the slicer shows for the flap servo well wall: it’s really asking a lot to get these to fuse together. It can be done on a well sorted printer though.

    • This reply was modified 2 years, 5 months ago by gnt2003gnt2003.
    • This reply was modified 2 years, 5 months ago by gnt2003gnt2003.
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    in reply to: P-38 printing question #32038
    gnt2003gnt2003
    Participant

    Wow – that’s looking a lot better. Is the overall weight right?
    I think you have two separate problems though. The loose plastic is one thing. That might be related to your slicer (bridging/overlap) settings, but I’m not really enough of an expert to know.
    And then you have some under-extrusion (the holes in the wing surface). I don’t think that’s slicer related, you need to play with your retract settings a bit more – have you investigated ‘extra restart distance’ or whatever CURA calls it? And how does the little stringing tower come out now?
    What does the internal structure of your wing look like? Better to have some fine stringing there, than holes in the wing, I have a feeling you may be over-doing the retract and so leaving a lag before the nozzle begins feeding again which leads to a hole.
    Try zooming into the sliced model part exactly where these holes appear and figure out whether the hole is caused at the end of a print run, or after a retract. In Simplify 3D you can tweak these two settings, and I assume you can do so in CURA too somehow.

    Try 3DPrintLabs support, they have sliced things for other customers, and they really know what they are doing. Simplify3D does work, really well, but it may not fix these problems. You will have others though. The nose-cone/cannons using CURA are a challenge, as are end parts of the tail booms…(though g-code editing could probably save you buying it just for that, I can’t imagine not having some idea of what the printer will be doing when!).

    in reply to: P-38 printing question #31986
    gnt2003gnt2003
    Participant

    I’ve a feeling your nozzle is a bit hot – that’s leading to stringing and the towers are still molten when the head goes back to add more plastic. Try decreasing the nozzle temp in 5 or 10 degree increments, the set and displayed temp is a guide only and there’s not really any point tuning your retract settings until you have your nozzle temp sorted as the two are closely interrelated. Print that tower on a 2 or 3 layer raft to give it something to sit on. That will also make the bed level less critical.

    What is that black blob? You could have a partially clogged nozzle, and that black thing might be burnt plastic. That is unlikely if filament flows nicely downwards out of your hot end when you extrude manually, but if it curls up into spaghetti and sticks to the nozzle, you may have a blockage. There seems to be a lot of plastic squidged out around the perimeter of the tower. Are you sure you have the bed level and at the corrent distance from the nozzle for the first layer?

    It often pays to print a brim, or a skirt around a part to prime the nozzle and so get the plastic flowing nicely before you start printing the part proper – and on the P-38 a lot of people find a brim is essential on most parts to help keep them stuck to the bed during printing.

Viewing 15 posts - 1 through 15 (of 64 total)