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Newbie's first steps and lessons learnt  

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JM
 JM
(@jm)
Active Member
Newbie's first steps and lessons learnt

I've had my mini for nearly a month ... I didn't know what to expect and I'm blown away with the quality of the prints. I'd spent the last six months trawling these boards reading about other's experiences and worrying if I should pre-buy 'this' replacement part or 'that' upgrade. When it arrived, I just assembled it, I didn't even bother with the hot end - heater block gap adjustment that everyone talks about I just printed and wow! (I could include pics of 'benchy's' and bits but there are plenty of examples elsewhere).

That said, I have learned a few things over this last month so I thought I'd put my experiences in a post on the off chance that they might be of help to fellow 'newbies'. I hadn't seen anything on the first point (below) and I was disappointed at first, until I worked out what I was doing wrong.

1. I'd read that PETG was strong and flexible and more suited to outdoor projects so when I tried to make some leg restraints to stop lightweight patio chairs blowing away in the wind, I tried to make some brackets that would clip over decking boards ... and the aforementioned 'strong' / 'flexible' PETG snapped 😫  ... OK - I know you experienced types have probably worked out what I did wrong ... but I didn't find anything to explain it - I was just disappointed with the performance of PETG.
... if you need strength in a particular direction make sure you print with the fibres aligned along that plane (i.e. if you need strength and flexibility in say a clip, print the clip in the X-Y plane not in the Z plane so that the filament flows along the direction of strength). There is no strength / minimal strength between layers. Yes - I know that's material science '101' but I didn't enroll on that course 😊.

2. PETG sticks better to the textured plate if you 'up' the printbed temperature (I got it to stick at 90 deg - Prusa's built in setting is 85 deg) - I was also very reluctant to get the print nozzle 'up close and personal' with the printbed (for fear of gouging a trench) but it helped when I lowered the first layer ... just a bit 😓 (obviously everyone's machine is set up differently so actual numbers are not relevant).
... as a corollary to this point, I found that fine tuning the 1st layer Z height 'on the fly' is remembered by the mini on subsequent prints - changing the bed temperature (from the same 'tuning' menu) is not remembered - you have to change the profile in Prusaslic3r.

3. I started to get adhesion issues with the smooth plate despite religiously cleaning it with IPA between prints and wearing latex gloves when handling the plate. Eventually I held the plate in a different light and I saw grease marks so I washed the plate in washing up liquid (dish soap to readers on the other side of the pond) and it worked fine after that. So I now give it a wash every ½ dozen prints or so.
... strangely, Prusa do not recommend holding the plate in running water - don't know why ... it's the easiest way to get soapy water off.

4. I've needed to print an object which was very close to the edges of the print area (using the diagonal wasn't an option) and the line round the edge of the print took it over the line ... I've only just found out that you can turn the 'outline' off in Prusaslic3r 🤭 (skirt and brim:set no of loops to 0).

Now I know that a lot (if not all) of the above is 'basics' and most of you guys (... that's the 'generic' term applying to both sexes ... I was going to use 'guys and gals' but I think that might have 'Jimmy Saville' connotations ... and we don't want to go there 😱)  know it already ... but it was news to me - and as I said I'd spent 6 months reading up whilst waiting for my mini - so I thought I'd put it here (one more place for someone to find it).

so that's a list of the first few things I've come across ... and tripped up over - and there's plainly a whole host of other pitfalls to come but so far it's been brilliant.

 

This topic was modified 4 years ago by JM
Posted : 11/07/2020 7:22 pm
JM
 JM
(@jm)
Active Member
Topic starter answered:
RE: Newbie's first steps and lessons learnt

A cautionary tale ... although not strictly a 'first prints troubleshooting' issue (more of a first ordering of filament gaffe).

As part of my introduction to 3D printing I ordered some extra filament from Prusa shortly after getting the mini. I thought I was 'saving a few bob' by selecting the 'cheap' courier option ...

...Hermes 😫.

Well 'cheap' covers it in all connotations of the word - it's now nearly a month since I ordered it and they still haven't delivered, despite having received it from Prusa two weeks ago. They've supposedly tried to deliver it 4 times and each time they couldn't deliver because "they weren't able to deliver the parcel to the address they had" ... I've checked with the Prusa support and they have the correct address (the same one DPD used to successfully deliver my mini) ... Hermes will not tell me what's wrong with the address they have - they'll only talk to Prusa (... who've got the correct address) - seems like a circular argument here - I doubt I'll ever see that roll of filament.

So the moral of the story is you may think the Hermes option is value for money ... you couldn't be more wrong

DON'T USE HERMES

 

This post was modified 4 years ago by JM
Posted : 11/07/2020 8:03 pm
janthonygeyer
(@janthonygeyer)
New Member
RE: Newbie's first steps and lessons learnt

My issues weren't immediate but I just started having similar problems, so I am interested if you can find a solution. I didn't have any issues the first week of having my printer, but now the material comes out of the nozzle at a slight angle which gives it a tendency to curl back onto the extruder. After lots of purging, tip cleaning, and loading/unloading material, I am still failing more prints than I am not. 

Posted : 11/07/2020 8:50 pm
JM
 JM
(@jm)
Active Member
Topic starter answered:
RE: Newbie's first steps and lessons learnt

@janthonygeyer

I've noticed filament curling back towards the hot end when it seeps through when the nozzle is warming up. This gets wiped off when the printer does its line of filament at the front of the plate at the start of the print and after that the nozzle is never far enough away from the bed or the previous line of filament for it to curl.

I'm no expert but

1. Are the prints failing due to lack of bed adhesion?

2. Which filament type / plate combination are you using?
- if it's PETG / textured plate is the bed temperature high enough (a friend of mine prints PETG at 95 - although I get away with 90)? Is the nozzle close enough to the plate? Do a first layer calibration test - does the filament stick? / are the corners square? / does the little square at the end look like the manual says it should?
- if it's PLA / smooth plate have you given it a wash with soapy water and rinse afterwards (washing up liquid - not 'soap'... unless you're American in which case 'dish soap not hand soap'  😀)

If the print is stuck to the bed OK and the print failure is due to something other than print movement then it's beyond my experience and hopefully one of the experts will offer some suggestions.

Posted : 11/07/2020 9:18 pm
JM
 JM
(@jm)
Active Member
Topic starter answered:
RE: Newbie's first steps and lessons learnt

@janthonygeyer

Just a thought ... I've printed off the molds and made a silicone sock for the mini. It's certainly dot had any detrimental effect and at the very least it would save you form having to clean the hot end regularly. Printing in a draughty place also results in inconsistent results - the sock goes part way to offsetting the effects of draughts, although I suspect an enclosure round the printer would do more if draughts are a problem. There are many designs for enclosures on these boards - I'm part way through making one myself (that's what I wanted the roll of filament for that Hermes can't deliver 🙄 )

This post was modified 4 years ago by JM
Posted : 11/07/2020 9:33 pm
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