3D Printers

[Chriske]

4 hours ago, Stub Mandrel said:

Yes Chris, but you'd print your own breakfast cereal if you could! 🙂

PLA is made of....corn..!!

Good thinking Neil..
Thanks for the tip..😊

[Gina]

Having fixed the hotend cooling fan it now sends too much vibration to the Precision Piezo Z probe sensor and causes triggering before the bed reaches the nozzle.  I thought of trying a different mounting method which meant work but then though of turning off the fan just during the Z homing - shouldn't warm up too much in that time.  M106 P1 S0 should turn the fan off but doesn't.  Nor does M106 P1 S0 I0 or M106 P1 S0 I1.  Thought "I'll ask the GCode gurus on SGL" and went and did my grocery shopping.

Meanwhile, my brain had been active - M106 P1 S1 I0 F500 H1 T45  turns on thermostatic control so that the hotend fan runs when the hotend is above 45°C so I thought "Maybe if I set the temperature well above normal range the fan will turn off" so tried M106 P1 S1 I0 F500 H1 T300 and it worked.

My homez.g code now reads :-

; homez.g
; called to home the Z axis
;
G91                        ; relative positioning
G1 Z5 F6000                ; lift Z relative to current position
G90                        ; absolute positioning
G1 X150 Y150 F6000         ; go to first probe point  **********************************
M106 P1 S1 I0 F500 H1 T300 ; Set fan 1 value, Thermostatic control is above normal range to turn fan off
G4 S2                      ; Wait for fan to stop                 
G30                        ; home Z by probing the bed
M106 P1 S1 I0 F500 H1 T45  ; Set fan 1 value, PWM signal inversion and frequency. Thermostatic control is turned on

Still wonder why M106 P1 S0 didn't work as the Duet web page says but found a fudge so that'll do.

 

Edited October 9, 2019 by Gina

[Thalestris24]

Gosh, it's just over a year since I started this thread! I never did get around to buying a 3D printer kit... But... but... Now I think I really do want to get one Is the Ender 3 Pro still a reasonable starter? It's going for around £220 at the mo which seems affordable. I just want to print smallish things mostly linked to astro stuff, maybe no more than about 12cm square by maybe 8cm high. Until I get one of these things I will know nothing, and have no feel for the ins and outs of 3d printing, so have to just dive in! Any thoughts or other make suggestions?

Cheers

Louise

[RolandKol]

9 minutes ago, Thalestris24 said:

Gosh, it's just over a year since I started this thread! I never did get around to buying a 3D printer kit... But... but... Now I think I really do want to get one Is the Ender 3 Pro still a reasonable starter? It's going for around £220 at the mo which seems affordable. I just want to print smallish things mostly linked to astro stuff, maybe no more than about 12cm square by maybe 8cm high. Until I get one of these things I will know nothing, and have no feel for the ins and outs of 3d printing, so have to just dive in! Any thoughts or other make suggestions?

Cheers

Louise

It looks like Ender 3 is the most popular entry level printer. I thought it is even cheaper at the moment, something like £170.
The only competitor in this price range I can think of, is Anycubic Mega-S, which is a bit more expensive (costs £220), but comes partly assembled.
I have not used Ender. I was in between these two printers initially... Do not remember why I went Mega way...
It had some problems, which needed some time investments to deal with, like bed warping and thermistor failure, but nothing serious and acceptable for such a price. 

P.S.

Ach... I was not sure how difficult it was to assemble  Ender an how accurate it should be... Partly assembled printer won.

Now, I would go for a cheaper option
 

[Mognet]

From the YouTube reviews I've seen, it looks like the Ender 3 is not just a good and inexpensive starter machine, it will be good for the average user for a number of years

I went for the larger print size of the Creality CR-10 instead of the Ender 3. Assembly isn't difficult and is quoted as being around ten minutes. As one of my cats decided she wanted to "help", it was a lot longer for me! I watched a YouTube video as an assembly guide, which gave some setup and adjustment information that the supplied booklet didn't.

This is the first print, at 0.20mm and without changing any other settings. I had a little issue with adhesion on the glass bed to start with, but solved it with a light covering from a glue stick

 

[PeterW]

Colleague just got one and it seems to do the job well.

Peter

[Thalestris24]

The Ender 3 Pro does look quite good. I'm a bit concerned about the durability and stiffness of things I might print though. Apparently, PLA, though environmentally friendly, does tend to break down over time. That really only leaves ABS which I know isn't so stiff? I need stiffness and durability for astro parts/stuff. I've read about PETG but maybe the Ender 3 can't cope with the higher temperatures needed? Any thoughts?

Thanks

Louise

Any thoughts?

[Gina]

PETG uses lower temperatures than ABS and doesn't produce the noxious fumes that ABS does in printing.

[Mognet]

PLA does degrade, but not easily. There's a bit about it on Wikipedia https://en.wikipedia.org/wiki/Polylactic_acid (I'll add that chemistry is not my strong point, so I don't understand much of it) Angus of Maker's Muse has a more practical demonstration https://www.youtube.com/watch?v=qqNfa_zExRU

I have seen some a couple of things about mechanical strength of PLA prints, but I can't remember where now

[PeterW]

I always over engineer things... maybe as I don’t have such delicate CAD skills as colleagues. If the part did start to degrade  (not come across it myself) you could always run off another one. 
PEter

[Thalestris24]

I'm probably overthinking things - I do that! The designer of the Lowspec spectrometer (which is one thing I want to build) used pla so it must be ok for prototyping, at least. Maybe I could also spray paint or otherwise coat the printed parts to improve durability.

Creality UK seem to be out of stock with the Ender 3 Pro at the moment though Amazon appears to have them.

Louise

[johninderby]

I have seen this stuff for coating 3D prints but not tried it myself.

https://www.amazon.co.uk/XTC-3D-High-Performance-Print-Coating/dp/B00PFXK4JY/ref=asc_df_B00PFXK4JY/?tag=googshopuk-21&linkCode=df0&hvadid=344406929468&hvpos=1o3&hvnetw=g&hvrand=16626825339239771609&hvpone=&hvptwo=&hvqmt=&hvdev=t&hvdvcmdl=&hvlocint=&hvlocphy=&hvtargid=pla-307514694446&psc=1

 

[JamesF]

If you're worried about the longevity of PLA perhaps a revisit of this post might help:

https://stargazerslounge.com/topic/322302-3d-printers/?do=findComment&comment=3710662

James

[Mognet]

13 minutes ago, Thalestris24 said:

I'm probably overthinking things - I do that! The designer of the Lowspec spectrometer (which is one thing I want to build) used pla so it must be ok for prototyping, at least. Maybe I could also spray paint or otherwise coat the printed parts to improve durability.

Creality UK seem to be out of stock with the Ender 3 Pro at the moment though Amazon appears to have them.

Louise

If it's this spectrograph on Thingiverse, then it should be fine. The instructions say to print it with 50-80% infill, which should make it fairly tough

I bought my CR10S from Technology Outlet, and the have the Ender 3 Pro in stock at the moment

[Thalestris24]

1 minute ago, Mognet said:

If it's this spectrograph on Thingiverse, then it should be fine. The instructions say to print it with 50-80% infill, which should make it fairly tough

I bought my CR10S from Technology Outlet, and the have the Ender 3 Pro in stock at the moment

Yes, that's the one! I've started getting the parts in Creality uk are a bit ambiguous - it says 'out of stock' but with a green tick next to it - hmm... As you say, there are other sellers though I've read you need to buy from Creality to get their support, should one need it. It may not be a big deal in reality. Anyway, I've contacted them to check their stock situation.

Louise

[PeterW]

XTC 3D is like a gloss paint coat. Not checked how it improves strength, but PLA (as long as it’s not too thin) should be fine. For strength I use 6+ walls/ceiling/floor and then up the infill. If you can ant to tap threads then the extra wall thickness is needed. I have a colleague trying to “flame polish” PLA ti achivw the same result as acetone vapour smoothing does with ABS. He reports improved impact resistance (fewer rough bits to initiate cracks, but he’s seen some warping and bubbling...)

PEter

[Chriske]

Best is to learn all about the slicer you're using, there's absolutely no need to coat the outer perimeter to have a very smooth perimeter in case of a 0.4mm nozzle.
I know, I know, it's a bit blunt(so sorry in advance..!), but sometimes I see pictures of printed parts on this forum that I myself would throw away and start all over again because of it's bad perimeters. For me the most outer perimeter should be perfect. That's what we all want, perfect perimeters isn't it..? If there's no mechanical malfunction on the printer itself, most of the errors are caused by bad settings in the slicer.
Strength of printed parts, also it all has to do with the settings in your slicer. When demonstrating about printed part's strength to spectators(during open door) I give them a printed part on which they can stand on. And no I do not pick a child to stand on that printed part. And it's not a solid part either, it is a hollow cylinder.

Before I decided(that was years ago) which filament I was going to use for most of my parts I did tests on solid parts. It was a completely different test I also did to test what colour would be best to use in sunny conditions).  Anyway that test-part was 100x20x10mm, I made 5 of these parts each all with different infill and a few different materials. All parts had 3 perimeters. It took me almost 2 days to test all these different materials/infills.  ABS(I never use it myself). but did add that in my test because my friend Marc asked me to.
Half of the length of that test-part was clamped on my workbench, the other half was hanging free above the floor. Hanging on that part above the floor there was a bucket that I filled with brass, lead,...  The most promising infill (for PLA) was 'Line infill' at 40%. After about 30kg that small part started to bend. It needed 55 kg before it eventually cracked. To be clear, that bucket was not hanging close to my workbench, but at the very tip of that part.
Under stress ABS bended sooner compared to PLA. But PLA did crack sooner. A few times I stopped mid-test to see what would happen with these parts under stress, All PLA parts returned to it's original shape, the ABS parts did not.
Anyway, my point is : most of the time, standard settings of a new installed slicer is not always the best way to go. It needs to be tuned.

Yes I saw the test too that Angus did, but the man lives in Australia...!! Environmental conditions down-under are completely different..! It is a hot country..!! If Angus would do these same tests in our milder countries the result would be completely different. That is btw why I did my own tests.

[Thalestris24]

BTW has anyone tried carbon fibre or other reinforced pla? Just curious, really, but also thinking ahead to a possible MkII version. The Lowspec spectrometer is going to be reliant on the stiffness of the parts. Ideally, it should be made of metal but that's not going to happen! I may be overthinking again ha ha.

Louise

[Stub Mandrel]

I think I will make a PLA flower pot. That shoudl be the best possible test of how long it can survive in adverse conditions.

I would have NO worries about its lifetime if allowed to dry if it gets wet and away from constant exposure to sunlight.

[Gina]

I've not tried carbon fill but have tried wood fill - horribly difficult to print as it's very brittle.  I also have bronzefill PLA which is very heavy and bought for printing weights.  Carbon fill wears out nozzles at an alarming rate unless you use steel or ruby nozzles.

[Chriske]

2 minutes ago, Gina said:

Carbon fill wears out nozzles at an alarming rate unless you use steel or ruby nozzles.

Correct, a friend of mine tried it, and for every reel of filament you need a new brass nozzle.

[Chriske]

4 hours ago, Thalestris24 said:

....or other reinforced pla?

Printing small parts there's absolutely no need to reinforce them. The trick is to find out how many 'Perimeters' and what 'Infill' you need to set in your slicer to make that thing strong and stiff. Most (almost all) beginners underestimate the strength of printed parts. There's one important rule : Never-ever print slim-line parts. Printing things to thin is the very start of frustration. The internet is literal filled with a zillion downloadable projects/parts designed that are way to thin. It's tempting and an easy way to start printing, don't do it.

Printing larger parts, and I mean really large, reinforce it by adding steel rods or threaded rods. But as I read it higher up, your not planning to.

[johninderby]

Yes printing really thin parts can be frustrating. Recently had to print a snap in cover plate for a bit of equipment about 150mm x 100mm and 1.5mm thick. Even with a substantial raft took three prints to get a good one. I knew it would be a PITA but couldn’t make it any thicker or add ribbing. 🤬

Edited October 13, 2019 by johninderby

[Thalestris24]

8 minutes ago, Chriske said:

Printing small parts there's absolutely no need to reinforce them. The trick is to find out how many 'Perimeters' and what 'Infill' you need to set in your slicer to make that thing strong and stiff. Most (almost all) beginners underestimate the strength of printed parts. There's one important rule : Never-ever print slim-line parts. Printing things to thin is the very start of frustration. The internet is literal filled with a zillion downloadable projects/parts designed that are way to thin. It's tempting and an easy way to start printing, don't do it.

Printing larger parts, and I mean really large, reinforce it by adding steel rods or threaded rods. But as I read it higher up, your not planning to.

Yeah, I'm intending to print somebody else's design of a diy astro spectrometer so it would be probably be opening a can of worms were I to attempt to change any dimensions. It's only quite small (of the order of about 100mm on a side, and maybe 70mm deep)  - mostly a shaped box/enclosure and fittings for the optical components with telescope and camera interfaces. As long as it stays stiff enough it'll be ok but might end up just being a prototype...

Louise

[Gina]

6 minutes ago, johninderby said:

Yes printing really thin parts can be frustrating. Recently had to print a snap in cover plate for a bit of equipment about 150mm x 100mm and 1.5mm thick. Even with a substantial raft took three prints to get a good one. I knew it would be a PITA but couldn’t make it any thicker or add ribbing. 🤬

Why not?

Edited October 13, 2019 by Gina