Why I would not buy Original Prusa i3 ever again  

Re: Why I would not buy Original Prusa i3 ever again

Hi Marcin

It's very sad to see comments like these, especially when most (in my very humble opinion) can be put down to a very poorly assembled printer.

Obviously this printer was not meant for you, so it is better that you go elsewhere; maybe somewhere that support is simply not available, or somewhere else where the printers cost twice the price and don't do such a good job. Or maybe 3d printing is simply not for you.

The vast majority of users on this forum are extremely happy with the Prusa i3 Original; they are happy to produce great prints at low cost and if they do suffer some kind of technical fault, they work it out, discuss it here or get help from support. Anyone with basic levels of common sense and engineering skills can quickly and easily prevent and resolve the issues that you post.

And as an aside, fans do fail; they are really low-cost items That's probably why they are quick and easy to replace.

Peter

P.S. RTFM

Re: Why I would not buy Original Prusa i3 ever again

i might be exaggerating since I'm angry but suggesting that I'm too dumb for this stuff? Not the best approach, I can tell you that.
Oh well, in such case It's prabobly pointless to tackle things I mentioned.

Re: Why I would not buy Original Prusa i3 ever again

Marcin

Don't think I suggested what you have suggested. As always, if you would like some help with your issues, please ask.

Even though like you, I am just a simple user (I received my Prusa Original almost 3 months ago), I have put the time in to finding out as much as I can about these printers, and I am always willing to help.

Peter

Re: Why I would not buy Original Prusa i3 ever again

I prefer to look for information on my own and ask only if I find nothing which might be the reson why some problems stacked on top of each other, maybe things I had found were only half-measures. Gonna cool down and give this stuff another, fair look tomorrow. If things continue to be bad I will refresh this topic within the next few days.

Re: Why I would not buy Original Prusa i3 ever again

Marcin

That was exactly my path. I guess I was somewhat luckier than you, and have been able to cure any issues before they got to me.

If you want to go further with this and would like my input, you can always PM me and we can discuss this via email.

Peter

Re: Why I would not buy Original Prusa i3 ever again

As with all equipment, there is a balance between cost and function. I think the electronic case is poorly implemented, so I downloaded a new one from thingiverse.

I think the cable management (coiled plastic) is unacceptable, so I downloaded and printed cable chain from thingiverse.

It's odd to me that ribbon cable is used to connect the LCD to the controller. I personally would have chosen 10baseT cable with 8p8c connectors or something similar. Far more reliable. Ribbon cable is easy to damage and a poor choice for serial data transmission over any distance due to attenuation between conductors.

The rotary/push interface on the controller is touchy and easy to pick the wrong item.

The limit switch attachment is sub-optimal. I'll find or design something to replace it.

I would have designed brackets for the threaded rod alignment, but what is there works fine.

The z-axis couplers are a mistake and will need to be replaced. The tubing is not durable enough, although it is an effective cheap solution. This will entail reworking the limit switch holder.

Overall I anticipate printing and replacing a fair number of components.

No big deal. Overall it's a great printer and it's helped me jump in to printing. I'll be building a dual extruder printer very soon, and possibly a kossel. I have no regrets. It is a tested set of components that got me up and printing quickly with a minimum of frustration. That is exactly what I wanted.

Re: Why I would not buy Original Prusa i3 ever again

What do you guys suggest is the best filament to print 3d printer parts out of?

Re: Why I would not buy Original Prusa i3 ever again

Alex

Josef was on here the other day and mentioned that most parts can be printed with PLA. Personally I would prefer to print parts close to the hot end with ABS.

Peter

Re: Why I would not buy Original Prusa i3 ever again

Brian

I disagree with some of your comments, but would add that ribbon cable is quite acceptable. 20 cores are required so 3 runs of Cat5 TP cable would be required.

I have many years experience with early SCSI cables - 50 core ribbon cable - and made cables up to 2 feet long running inside a computer where there is plenty of electrical interference.

I did agree with your comments regarding the Z connectors which I have replaced with aluminium - printing modded Z end stop holders - but the plastic tube/heat shrink is in some ways a better solution and, when installed properly, works well.

Peter

Re: Why I would not buy Original Prusa i3 ever again

IMHO

CAT5 is a poor choice for this situation. CAT5 uses differential signalling. The signals used between the mini-RAMBo and the LCD do not lend themselves to the balanced "pairing" nature of the twists in CAT5 cabling.

A parallel cable is adequate for the length of run so long as you don't run parallel to high current wires. There are many many examples in the computing industry where short parallel runs are totally fine.

Also, the coil-cable-cover is somewhat common in industrial environments to an extent. There are other alternatives, but comparing cost vs. benefits, but I don't see a problem in this situation.

Agree on the heat bed mounting/levelling. There is room for improvement here.

Re: Why I would not buy Original Prusa i3 ever again

Hi Marcin,
I am sorry you feel this way. First and foremost, if you have mechanical problem or faulty part, it is important to use livechat or email as I state in Before you ask ... Troubleshooting VIDEO! http://shop.prusa3d.com/forum/prusa-i3-kit-building-calibrating-first-print-main-f6/-before-you-ask-troubleshooting-video--t472.html

-Broken turbine print fan after 3 weeks

We can get you a replacement free of charge. Did it just stop spinning?

-Broken threaded rods (sanded threading) after around 350h (3 months)

We can get you a replacement free of charge. I never saw that and we have printers in the farm for years. Are you sure there was no abrasive substance on the rods?

-After some time nuts started rotating along with threaded rods preventing extruder from going up and down

I guess it's the same thing as previous issue.

- PSU fan generating hi-pitched noise every now and then (have to reset it few times before it goes back to normal)

We can exchange your PSU with a fanless variant.

-overheating (literally melting) heatingbed connector if arraged the way manual says.

Sorry, there is no way the 16A molex connector can melt when assembled properly. Best thin now is to solder the cables on the back side of the RAMBo.

-screen showing random letters at... random.

Do you regularly update the FW? It now can fix itself. Also check the video for the proper way how to route the LCD cables.

-slicer software super buggy and often not working properly

Can you elaborate? Fell free to check this forum for free and paid alternatives which are fully compatible.

-no belt tensioning system

Do you really have trouble or just trying to add some more stuff in to the list? I never seen a printer where are not able to set proper tension. It means more parts which can break.

-poorly desined MOBO box which comes off the aliminium frame after a while (forced to use zip-ties instead of screws)

Can I see a photo of this exact issue? It is screwed with stainless steel screws into aluminium frame, I don't see how it can come off.

-Stuttering at random extruder motor
BTW would be great if you could tell me why the extruder motor "jams" at random going back and forward "shaking"

Can I see a picture of your wiring? If the cables have proper stress relief according to manual. Motor shaking means a broken cable.

Re: Why I would not buy Original Prusa i3 ever again

Hi Marcin,
I am sorry you feel this way. First and foremost, if you have mechanical problem or faulty part, it is important to use livechat or email as I state in Before you ask ... Troubleshooting VIDEO! http://shop.prusa3d.com/forum/prusa-i3-kit-building-calibrating-first-print-main-f6/-before-you-ask-troubleshooting-video--t472.html

-Broken turbine print fan after 3 weeks

We can get you a replacement free of charge. Did it just stop spinning?

That would be great and yes. Hooked it to a battery to make sure and it didn't react as well so I'm certain it's dead.

-Broken threaded rods (sanded threading) after around 350h (3 months)

We can get you a replacement free of charge. I never saw that and we have printers in the farm for years. Are you sure there was no abrasive substance on the rods?

Here's a thing. I lubed them but due to the fact rods are covered with paint(?) the paint came off and I think that was the main reason for threading to fall victim to debris accumulating around the nut. I would highly recommend using clean steel in the future. That's my theory :). Already bought a replacement so I don't need extras but thank you. If these break as fast as the first ones I will know there's something I'm doing wrong.

-After some time nuts started rotating along with threaded rods preventing extruder from going up and down

I guess it's the same thing as previous issue.

- PSU fan generating hi-pitched noise every now and then (have to reset it few times before it goes back to normal)

We can exchange your PSU with a fanless variant.

Not sure down-grade is the best solution ;). Am I the first person with this problems?

-overheating (literally melting) heatingbed connector if arraged the way manual says.

Sorry, there is no way the 16A molex connector can melt when assembled properly. Best thin now is to solder the cables on the back side of the RAMBo.

I read the manual and the forum posts. I know what causes that and believe me I screwed that connector as hard as I could, tried different options and after replacing it for the 3rd time I decided to connect it from below and it's ok since then no overheating and disconnecting heatingbed.

-screen showing random letters at... random.

Do you regularly update the FW? It now can fix itself. Also check the video for the proper way how to route the LCD cables.

Didn't know about that - my bad 🙂

-slicer software super buggy and often not working properly

Can you elaborate? Fell free to check this forum for free and paid alternatives which are fully compatible.

Freezing, models not loading, lagging. I know it's a common problem with Slic3r. Right now I'm using cura and it's okay 🙂

-no belt tensioning system

Do you really have trouble or just trying to add some more stuff in to the list? I never seen a printer where are not able to set proper tension. It means more parts which can break.

I think it would be a nice option to add. Not saying there's a problem with that, just a small upgrade which would be easy to make 🙂

-poorly desined MOBO box which comes off the aliminium frame after a while (forced to use zip-ties instead of screws)

Can I see a photo of this exact issue? It is screwed with stainless steel screws into aluminium frame, I don't see how it can come off.

Really no need for a photo. Screw holes were loose from the very beginning and after a while they were unable to hold the plastic plates in place. Using longer screws with a nut would be much better, that's my point

-Stuttering at random extruder motor
BTW would be great if you could tell me why the extruder motor "jams" at random going back and forward "shaking"

Can I see a picture of your wiring? If the cables have proper stress relief according to manual. Motor shaking means a broken cable.
I just noticed that cables are burnt so at some point I placed them too close to the hotend and some of the wiring is naked so I can imagine when they contact one of the metal elements it causes a short cirquit and stuttering of the motor - my bad, sorry.

Re: Why I would not buy Original Prusa i3 ever again

Marcin, there are several good designs for a belt tensioning system on Thingiverse for the i3 if you want one.

Regarding the rods, i gotta wonder if whatever lube you used maybe had a reaction with the paint or something. Not sure what enviorment your printer is in, possibly the lubricant allowed atmospheric dust in the air to stick to it. I have two i3's one came with the painted black rods you have, and the other with plain steel. The older one (with the black rods) has about 1000 hours into it now, with no signs of stripping. With the Z-axis being the least moving of all , id doubt there is any need for any kind of lubrication.

Re: Why I would not buy Original Prusa i3 ever again

Really no need for a photo. Screw holes were loose from the very beginning and after a while they were unable to hold the plastic plates in place. Using longer screws with a nut would be much better, that's my point[/u]
What I did when I assembled my printer was to use loctite out of habit for all the metal to metal screws (even those for stepper motors). This ensures that vibrations and the like won't make the screws come loose. I still have doubts about your screw threads being "worn out" from the start though. But get loctite

Re: Why I would not buy Original Prusa i3 ever again

Marcin.c

The post became very very long 🙂 I'll try to compact it.

Replacement parts: email or livechat, we make the replacements hassle free so don't worry to ask.

We shipped these PSUs only for couple weeks as more expensive alternative when our supplier ran out of the normal PSUs we use. With the numbers we ship out. You are not the only one with the PSU fan noise, but with the numbers we ship out we see every problem imaginable. So it's upto you 🙂

The M5 rods are not painted, it was black galvanised zinc (hope the term is correct in english). We stopped painting the m5 rods couple months ago, when we switched to completely different supplier of threaded and smooth rods. I can only imagine some foreign object got between the rod and nut and sanded away the thread?!

PCB connector: What do you mean by connected from below? Like I suggested?

Re: Why I would not buy Original Prusa i3 ever again

Ok, I will contact you via email :). By below I mean... as far as I remember there's a hole in the plate which through you should connect the bed to MOBO. Instead of that I connected it from below the plate where the free uncovered space is and since then it's okay. Works well so I'm not going to mess with it any further :P.

Re: Why I would not buy Original Prusa i3 ever again

Question - what I should do if my printer died in the middle of printing? Screen doesn't work. I can only hear PSU fan working when I turn it on. Computer doesn't see it as well...

Re: Why I would not buy Original Prusa i3 ever again

Hi Marcin

That sounds a tad fatal...

Best thing to do is to check that you have a 12V supply onto the RAMBo. If you don't then either the PSU has died or you have a connector issue (unlikely). If the latter, check the output from the PSU; you will have to remove the printed part on the PSU to get access to the outputs.

If you do have 12V on the RAMBo, then it would appear that something on the RAMBo has died (possibly the buck regulator). There will be test points on the board, but the best thing to do is to contact support (via Live Chat). Tell them what has happened and what you have tested.

Peter

Re: Why I would not buy Original Prusa i3 ever again

That's great because I'm having such an easy time with this machine :|. Thanks, I will let them know...