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View Full Version : $160 – $189 for a Prusa i3 clone!



nigelpearson
1st Apr 2022, 10:38 AM
I have been looking for a cheap printer for a few months, and tried a few times to get secondhand Ender 3 machines from Facebook Marketplace, but kept missing out on the cheaper ones. So, to eBay I went.


Cheapest local new one seems to be an Ender 2Pro for $239 posted:
https://www.ebay.com.au/itm/384726258552


but while looking I found a Prusa i3 clone for $189 posted:
https://www.ebay.com.au/itm/234242609516


You might now be able to get it for $170 posted.
Mine came with a March discount for $160 delivered!




So, a box of parts arrived on Wednesday:
397792397793


The "frame" is only Acrylic, so I might be glueing some extra gussets on, or bolting extra angle iron/Aluminium on as I assemble. Just need to find an assembly space, because the building instructions say:

4. Before you start, you can put all the part in order to save your time especially those screws and nuts. Do not mix them up.
5. Ensure you have the necessary skills to carry out the work, or enlist the help of someone who does.
6. Work on a big firm table or bench in a clean dry well-lit area.
:o



P.S. While eBaying, found nice large displays for Ender 3s. Local, $49 delivered:
https://www.ebay.com.au/itm/224707236268

BobL
1st Apr 2022, 11:33 AM
Rigidity is super important on 3D printers especially when you are looking at taller objects,

Prusas are excellent printers but the build volume is 200 x 200mm bed x 180mm tall .
The 180mm tall is probably because its acrylic but for only 180 high it should not need reinforcing.

The link you provided to the Creality Ender2 is for an Ender3 which is 220 x 220 x 250 which doesn't seem like much but is quite significant.

I have a Creality CR10S pro V2.
Initial and ongoing success in printing is highly operator dependent.
Creality are also good printers but for the average punter probably not quite as good as Prussia's.
Not sure about Prusa clones.

3D printers do need space around then even for a small printer, it's not like a paper printer.
You need some servicing space around it, maybe think about a cover (reduces noise), storage for filaments, and even a filament drier/dehydrator.

The transparent cylinder on the LHS is the heating compartment of my ($40) filament dehydrator
397794

What are you intending to print?

Mine came mostly assembled but I did have my son, who has 3 3D printers and about 7 year experience in running these helping me
The total time taken from opening the box, to completely assembled was about 25 minutes.
This included
- checking box contents and, (GASP) my son even bothered to (skim) read the instructions
- 10 of those minutes was spent looking for a lost socket screw (my desk in my study is a bit of a tip) and then giving up and getting one from the shed only to find the original screw was actually in the deeply recessed hole of an already tightened screw
It was my fault because I put it there. https://www.woodworkforums.com/images/smilies/actions/doh.gif

Calibration:
This involves making sure the printer bed is level to the head etc.
It has an auto leveller but a coarse bed levelling adjustment is necessary before the auto can work properly.
While coarse levelling we repeatedly ran out of thumbscrew range on one corner of the bed so we back tracked and found out we had missed an assembly step of making sure the X-axis was level.
This took about 50 minutes so we were printing our first blob in just over 75 minutes.

In the first few weeks I called tech support (my son) a few times simply because it was easier although I could probably have solved these minor probs myself. Since then printer has run almost flawlessly for 7 months up until the end of Dec when I slowed down on using as it puts out quite a bit of heat so long prints really heat up my study where the printer is located. This last week I've started printing again and had frustrating bed levelling issues which took me longer than I expected to sort out even with tech support. All this was probably because I haven't really had anything to do to the printer before this - if it happens again I will be able fix it in a few minutes.

nigelpearson
1st Apr 2022, 07:18 PM
You need some servicing space around it, maybe think about a cover (reduces noise), storage for filaments, and even a filament drier/dehydrator.


Dehydrator? Interesting. Hadn't thought plastic would absorb water!



What are you intending to print?

Case for small electrical switch panels and displays, maybe lathe wipers, cable clips, et c.

BaronJ
1st Apr 2022, 08:01 PM
Dehydrator? Interesting. Hadn't thought plastic would absorb water!

You should try weighing a chunk of Nylon before and after drying !

Remember this

397797 397798 397799

This is the Nylon60 lathe spindle nose thread protector that I made back in 2018. Well after being stood for a while, I found that it had become very hard to screw on to the spindle nose. I ended up re threading it in order to loosen it up. An hour or so laid on top of a heater dried it out enough to make it a loose fit. Since then a wipe with an oily cloth helps.

BobL
1st Apr 2022, 08:06 PM
Dehydrator? Interesting. Hadn't thought plastic would absorb water!
Yep and it makes a big difference. As the filament goes thru the heated nozzle absorbed water turns to steam and it creates bubbles in the print. It can lead to a poor finish or even a weaker structure if the bubbles occur in a critical spot.

I use a budget end food dehydrator ($50 on ebay). This one has four heat settings hottest supposedly is 68ºC but its closer to about 60ºC
I replaced the stack of food trays with a 1mm thick PC cylinder then stack the rolls of filament inside and run it overnight o dry it out. Then I store the rolls in sealed plastic garment bags which unfortunately do leak so if its been a few months between uses of a role I give them an ON burst in the dehydrator. The red thing is a Temp/Humid sensor connected to an arduino on top of the printer cabinet. I also have a PC cylinder about 2.5x taller than the one shown for bulk dehydration.

397800



Case for small electrical switch panels and displays, maybe lathe wipers, cable clips, etc.

Perfect. Thats also what I mainly use mine for. Here's a few I've done.
SCR speed controller.
Also did the glands and fan cover.
397801

Simple switch box
397802

Low res PID case - am redoing it in a larger size right now.
Also did the back gland on this one,
397803

nigelpearson
3rd Apr 2022, 07:23 PM
About 1 hour for the Y axis slides. PDF instructions aren't great and have a few errors - YouTube video is clearer. Most of that hour seemed to be peeling the paper off the Acrylic sheets:
397831

Then bolt together the base frame, and plate:
397832397833
Another 2 hours. Linear bearings are 8mm and a bit of a mixed bag (well, they came in a little bag :D).
Two slide nicely, and two feel a bit rough. I'm too lazy to inspect for defects, maybe file or scrape the ball carriers, and re-grease. So I put one smooth and rough on each rod.

Note that the plate cable ties onto the linear bearings! Kit of parts has white cable ties, but that will clash :C, so I gave up to come home and look for black ones :U

BobL
3rd Apr 2022, 07:45 PM
Looks nice.

The first 3D printer my son bought for me in 2014 came as a kit. No written instructions. Just 10 x 1 hour videos (taken from above) by a bloke trying to cover the assembly of 3 similar but different printer models so you had to keep your wits about you . I was somewhat put off by the blokes scabby bald head blocking the view from time to time. After 9.5 hours of video I got stuck and lost interest, I also couldn't really think of anything to print. A few weeks later my son asked me how it was going and he offered to take it home and had it going in a couple of hours. It stayed at his place until a few years back when he finally gave it back to me all upgraded etc but it was still very futzy to get prints out of it, besides it was easier for me to send my son a 3d file file and get him to print things than for me to set up the printer.

Then the price of plastic project boxes jumped by 100% and my son was reminding me that new printers were more user friendly so last year I finally bit the bullet. I had a couple of criteria like not-a-kit and a decent print volume so I forked out a fair few bucks but I have used it so much, much more than I ever though I would.

Back to the water issue.
This is a half decent finish with dried filament
397836

This is what I see (little lumps and streaks etc) if the plastic has been sitting in the open air on a bench for a few weeks.
I can be a lot worse than this.
397837

nigelpearson
5th Apr 2022, 01:16 AM
Another 4 or 5 hours. Kind of like doing a LEGO kit. Kind of fun.

Didn't like the way the Y axis belt was meant to run (which was drill two holes in the ends, and screw them into a block with 90°bends).

Decided to twist it, so that the tensioning roller actually rolls on the flat back of the belt, drilled a hole in the block for a cable tie, and used the belt teeth to grip onto itself (i.e. a loop):
397869397870


The Acrylic frame is surprisingly rigid. Has good gussetting and bracing:
397872397873397874397875


Some of the metal parts aren't finished as accurately as the Acrylic - some filing required:
397877397878397879

The X axis rails were binding just a little on one side:
397880397881
so its metal carrier needed some filing and bending.


Trickiest part was attaching tiny heatsinks onto these teeny tiny driver chips.
397882397883
Peeling the double sided thermal transfer tape was impossible!



Now I've just got to tidy up the cables to finish the build. Strangely, the manual and YouTube videos omit that part, so I might have to go searching for images online, to see what other people have tried.



Then its just the alignment/calibration.

BobL
5th Apr 2022, 09:36 AM
looking good Nice!

Yesterday I was back printing "teeny tiny mushrooms" for the grandies fairy garden (HA!) and decied to used some of the wood dust impreganated PLA and after printing two mushrooms the print head clogged. Again I suspect water, if the wood powder is not evenly distributed in the PLA and the wood absorbs water when it hits the filament heater it expands and clogs - this is the second time this has happened. I didn't use my dehydrator as I was processing some black olives!

397884

It's not only the nozzle that is clogged, the whole filament path is blocked. Normally I use my Ultrasonicator and dichloromethane to de-block these but I guess I will need to find another way.

Abnerj
6th Apr 2022, 09:21 AM
It's not only the nozzle that is clogged, the whole filament path is blocked. Normally I use my Ultrasonicator and dichloromethane to de-block these but I guess I will need to find another way.

If you haven't already tried it, Google the 'cold pull' method for clearing a filament blockage.

BobL
6th Apr 2022, 09:46 AM
If you haven't already tried it, Google the 'cold pull' method for clearing a filament blockage.

Thanks, I've use the cold pull method before but that was when I could at least get a piece of nylon filament into the hot end. The problem I had was that the old filament had broken off at the start of the Boden tube so whole hot end was clogged solid with filament.
Plus black goop had oozed out all over the place, covering the heat block etc - obviously nozzle was not tight enough and it needed a clean up.

I managed to get it clean by just warming the dissasembled hot end in dicholormethane (Cl2CH3). That stuff has a very low boing point (40ºC) and then evaporates away very quickly but it doesnt take long to soften the stuck filament so it can be drilled out with a 1.7mm bit. Once its out leaving it soaking in CL2CH3 for about half an hour cleaned it up.