Prusa Mini Clone from China  

RE: Prusa Mini Clone from China

Between testing and building this printer, I am learning a lot.  

My sheet test thread has helped me learn to better dial in my first layers.  I may have rushed to print prints.  

This thread has taught me how to fix, adjust, and build a mini.  If I have to take either my minis apart, I will be better able to do it in the future.  

RE: Prusa Mini Clone from China

Posted by: @charles-h13

Between testing and building this printer, I am learning a lot.  

My sheet test thread has helped me learn to better dial in my first layers.  I may have rushed to print prints.  

This thread has taught me how to fix, adjust, and build a mini.  If I have to take either my minis apart, I will be better able to do it in the future.  

It was also a great learning opportunity for me. If you assemble something from scratch it's much easier to diagnose an issue and setup stuff properly. I wish Prusa made a kit Mini version.

There is also one thing that I have to say about the clone that differs from oryginal. It's the PTFE tubing. In the clone there is one single tube from extruder gear down to the heatbreak (nozzle actualy) itself. The original one has additional tube inside the hotend and one inside the extruder. So 3 tubes with connections vs a single one. I like the clone approach much more. Clean and simple. Those additional PTFE tubes only add friction and possibly issues IMHO. I have already removed the PTFE tube provided with Bondtech heatbreak and will also remove the small one in the extruder when I find a go-trough connector with 8mm thread.

RE: Prusa Mini Clone from China

I did send a recommendation to them to offer it as a kit.  We will see.  

RE: Prusa Mini Clone from China

@charles-h13

so do you think a newby in 3D printing not having your experience , without another printer to print the plastic parts have any chance to have it working?

When you add your time , printing and material costs of filament, what is your final price estimate?

RE: Prusa Mini Clone from China

@zoltan

I would not recommend it to newbies on less they that extensive experience and are mechanical inclined.  It was a challenge and I had to reprint at least 4 parts.  

Total cost for me: $135.  I only added a roll of filament to print.  I used Urban Gray PETG and PC Blend.  Cheap PETG would lower that number.  

I did not use a full roll of filament.  

Heck, I am a physician and not mechanically inclined and I got it to work perfectly.  

RE: Prusa Mini Clone from China

Posted by: @goszu

[...] It's the PTFE tubing. In the clone there is one single tube from extruder gear down to the heatbreak (nozzle actualy) itself. 

So it's not an all-metal hotend? What maximum temperature can you set for the nozzle? Many clones are limited to 240C in firmware. If not, that PTFE can break down and emit nasty things.

Doesn't the Mini have an all-metal hotend? This is an important difference if so and will limit printing options and maintenance procedures.

RE: Prusa Mini Clone from China

@bobstro

I will disassemble a hotend and check.  It came assembled.  

RE: Prusa Mini Clone from China

Posted by: @charles-h13

I will disassemble a hotend and check.  It came assembled.  

Not to be preachy, but this is an opportunity where 3rd party reviewers can do some good homework and provide valuable input to the rest of the community (aka their viewer/readership). Rather than just assemble and comment on print quality, I'd like to see some in-depth investigative work into how money has been saved and more technical analysis.

• My understanding is that these printers are being advertised as running the Prusa firmware for the Mini.
• The Prusa Mini is rated to 280C printing temperatures. Not as high as the Mk3, but well beyond the 240C limit of a PTFE-lined hotend.
• Most low-end printers are limited to temps below 240C due to their use of PTFE-lined hotends. Apparently getting hotend designs right is tricky, so going with a PTFE tube down to the nozzle is a convenient cost-saving shortcut to precision design and manufacturing. Who knew?
• If an inexpensive printer is allowing the user to heat a PTFE-lined hotend up to 250C and beyond (the FYSETC page claims 300C), you are well into the range of temperatures that will cause PTFE to physically break down, causing long-term maintenance issues well beyond the first Benchy print. At higher temps, PTFE (Teflon) starts breaking down and emitting neurotoxins that are particularly dangerous to pets and certainly not safe for human long-term exposure (like a desk-top printer).

These things are manufactured and sold to a range of users with few or no safety precautions or certifications. It was only after outcry from the reviewer community that companies like Ender started shipping firmware with rudimentary fire safety features enabled. They continue to have issues with connectors and other wiring that can be a fire or safety hazard. Artillery is shipping printers with AC bed heating wiring improperly protected. I'm all for saving a few bucks, but a lot of people depend on 3rd party reviews to point out things like this when making gift buying decisions, and a lot of new and inexperienced users -- particularly young kids -- are oblivious to such things unless it's pointed out to them. If anybody is considering getting into the 3rd party review game, a set of safety tests would be a real differentiator to all the "they shipped me this printer for free and it's GREAT!" reviews we find on YouTube. I find the lack of safety testing for resin printers particularly egregious. I'd like to see more emphasis on product safety for products that are definitely being targeted towards younger users and new consumers.

If you're going to use the Prusa forums for your reviews, it would be very helpful to point out signficant deviations from Prusa's quality and safety measures as you do so!

RE: Prusa Mini Clone from China

@bobstro

It's like fighting against wind mills. AC beds without safety features and cable relief, Resin which is causing chemical burn, Laser cutters without any safety features... In the reviews it's usually only one sentence "please be careful". But the whole review gives you a feeling that this product is good, safe, inexpensive and easy to use.  Somebody without deeper knowledge just looks at the price tag and makes the decision based on that.

RE: Prusa Mini Clone from China

The PTFE tube does not extend to the nozzle.  The bed is 24V DC.  

RE: Prusa Mini Clone from China

Posted by: @bobstro

So it's not an all-metal hotend? What maximum temperature can you set for the nozzle? Many clones are limited to 240C in firmware. If not, that PTFE can break down and emit nasty things.

Doesn't the Mini have an all-metal hotend? This is an important difference if so and will limit printing options and maintenance procedures.

Yes, the clone hotend/heatbreak is NOT full metal. At least mine was not. PTFE tube goes straight down to the nozzle itself.

RE: Prusa Mini Clone from China

@goszu

Sounds link you have a different hotend.  Which maker?  

RE: Prusa Mini Clone from China

Prusa heatbreak:

RE: Prusa Mini Clone from China

Bondtech heatbreak:

FYSTEC Heatbreak:

RE: Prusa Mini Clone from China

All three require a piece of PTFE down the center that is inserted 43 mm.  The Bondtech and Prusa heatbreaks require a small piece and there is a break between the PTFE from the extruder motor and the piece the hotend, but the FYSTEC is one continuous piece from the hotend to the extruder.  It just inserts the 43 mm.  They are both the same distance from the nozzle (eyed and not measured).  

The Prusa and the other two are subtly different but the other two appear identical.  I hope this helps.  

RE: Prusa Mini Clone from China

Posted by: @charles-h13

@goszu

Sounds link you have a different hotend.  Which maker?  

FLSTC from Ali. The hotend was not assembled and heatbreak is just a straight trough pipe. That's why I replaced it with Bondtech heatbreak.

RE: Prusa Mini Clone from China

@charles-h13

I am starting to suspect that they sent you selected printer to please you if they sent it for review, because there's no way anyone ever received other than straight tube heatbreak where you have to run PTFE to the nozzle. Heck they do use PTFE-lined heatbreak with MK3S clones to this day! If you compare it to Prusa heatbreak, it's just a straight tube, while Prusa heatbreak has that narrow part at the bottom and PTFE does not touch nozzle, ever. Compare image below to mechanical part diagram from MINI Github: https://github.com/prusa3d/Original-Prusa-MINI/blob/master/DOCUMENTATION/MECHANICAL%20PARTS/mini-heatbreak.pdf

RE: Prusa Mini Clone from China

Posted by: @charles-h13

@goszu

Sounds link you have a different hotend.  Which maker?  

No, goszu has "normal" Fysetc hotend. It's you who have different hotend 😀 it's strange your came in assembled, that's never the case.

RE: Prusa Mini Clone from China

Posted by: @charles-h13

All three require a piece of PTFE down the center that is inserted 43 mm.  The Bondtech and Prusa heatbreaks require a small piece and there is a break between the PTFE from the extruder motor and the piece the hotend, but the FYSTEC is one continuous piece from the hotend to the extruder.  It just inserts the 43 mm.  They are both the same distance from the nozzle (eyed and not measured).  

The Prusa and the other two are subtly different but the other two appear identical.  I hope this helps.  

Looks like you've got a premium one like crawlerin mentioned. Mine is the "poor", ordinary version.

I used Bondtech one, bug got the PTFE straight trough without the provided 43mm piece.

RE: Prusa Mini Clone from China

@goszu

Yup.  That’s a different one.