Ebay SINTRON Kossel Mini full kit

Hey guys,

One another new Sintron Kossel Mini Kit owner joining your little community If say true I'm still reading this whole thread from the very first page, very interesting and useful to know your experience, caveats, workarounds... I'm currently at 20th page, but have no patience anymore and asking my question, sorry But still reading through though.
I built the frame, the electronics, calibrated it as much as I could, at least now I have rather flat hotend movements at the bed surface. Still have to do some more grinding of the diagonal rods ends, still some tension there...
It appeared that they forgot to package the Z levelling plastic part, Sintron Australia promised to re-send the part (of course not from Sydney this time around, but from China), but meanwhile I'm sure I can start with manual calibration.
The only thing that stops me to from trying to print is that my hotend fan is not spinning at all (even if I try to raise the temperature from Pronterface) though chinese doco says that it should constantly operate. Is it worth connecting it directly to 12v or it's important to leave it on the RAMPS output so it can pwm the speed? How the fan behaves for you guys?

Thank you for the ideas in advance,

This thread is super cool!
Levon

Hotend fan should be working at all times. Of course, if you plugged in the PWM control, you need to give the manual command to turn it in pronterface, or in your gcode when printing (M106 S255). you will be better off connecting the hotend fan directly to the PSU, and use the pwm controlled output to use with an object fan later when you want one.
in my experience, having to turn the fan on everytime you start a print will work for some time, but eventually you will forget once, and melt your effector or cause a jam.

If your printer uses Traxxas or similar joints then you can probably use washers to increase the bearing spacing at the effector to match the carriages.

---

Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

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Levon
Is it worth connecting it directly to 12v or it's important to leave it on the RAMPS output so it can pwm the speed? How the fan behaves for you guys?
Levon

Hi Levon. Welcome to our community.

This question, actually, was answered a couple of times in this thread, but I can repeat. It's better if hot-end fan is directly connected to 12V (i.e. to PSU) and constantly operates all the time. Just save PWM controlled D9 terminal for object fan, which is highly recommended if you will print with PLA.

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Tha_Reaper
Hotend fan should be working at all times. Of course, if you plugged in the PWM control, you need to give the manual command to turn it in pronterface, or in your gcode when printing (M106 S255). you will be better off connecting the hotend fan directly to the PSU, and use the pwm controlled output to use with an object fan later when you want one.
in my experience, having to turn the fan on everytime you start a print will work for some time, but eventually you will forget once, and melt your effector or cause a jam.

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GrAndAG

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Levon
Is it worth connecting it directly to 12v or it's important to leave it on the RAMPS output so it can pwm the speed? How the fan behaves for you guys?
Levon

Hi Levon. Welcome to our community.

This question, actually, was answered a couple of times in this thread, but I can repeat. It's better if hot-end fan is directly connected to 12V (i.e. to PSU) and constantly operates all the time. Just save PWM controlled D9 terminal for object fan, which is highly recommended if you will print with PLA.

Guys thanks for the lightning fast answers, all that makes sense. I'll go with that!

Edited 1 time(s). Last edit at 01/24/2016 07:59AM by Levon.

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chris81
Hi,

my carbon rods and traxxas ends arrived in the meantime. I can now print bigger parts without any binding. There is one huge problem that bothers me: The dimensions in the x-direction of my printer are too small. I just printed the duet case and it is 3mm too short in the x-direction ( the board won't fit into it )
Y-direction and Z are all good or very good.
I rotated the model in slic3r 90 deg and confirmed that now the other side of the case is too short.
What can I do to get this right? I am using autocalibration and a level to make sure my bed and columns are 90deg. Apparently I am missing something.

Chris

By no means it is a solution for geometry problems, but thought I'd share it anyway. This — [www.thingiverse.com] — is the design of the duet holder for sintron printer I created, which is probably somewhat tolerant to slight dimensional inaccuracies when you print with the right orientation for your inaccuracies.

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Tha_Reaper
Both the 5A and the 11A input should be connected to the (same) PSU. If you leave the 11A input not connected and only use the 5, the hotend and bed will not heat up.

You don't need seperate connections. Just plug in the wires together with other ones, but try to balance the load. For example: 5A and fan together on output 1, 11A on another output 2.

It is safe to connect the bed to the PSU directly.

The extruder is on the 5A line, only the bed is connected to the 11A fuse.

You can't connect the heatbed directly to a PSU, you need at least a relay ( SolidState Relay preferred ) for temp control.

-Olaf

Hi again guys, voila, I'm so happy, really did not expect that it will start printing straight away and so pretty not too bad very happy. By the way the filament supplied by Sintron did not stick to the bear alluminium bed without slight heating (60C degrees). I discarded the first piece of plastic mess. Other than that it's the very first 3d printed object! Will buy some Kapton tape tomorrow and try with cold bed.

The bottom layer is a bit melted out to the side, but that's because something happened in the extruder, after a second it started feeding the filament properly.

Need to add some heatsink to the MOSFET though

HAPPY!

Nice work Levon, that's a fantastic first print!

Looks like you're well on the way to printing some nice objects.

When printing pla, outdoor painters tape works much better compared to kapton. You only need kapton for the high temperatures that ABS require of the bed

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Tha_Reaper
When printing pla, outdoor painters tape works much better compared to kapton. You only need kapton for the high temperatures that ABS require of the bed

That second that. All I'm using is blue painters tape on the aluminum-bed, with a thin layer of Elmers glue-stick (applied just prior to the start of my prints), and I'm getting great results. I'm not even heating the bed.

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Levon
Hi again guys, voila, I'm so happy, really did not expect that it will start printing straight away and so pretty not too bad very happy. By the way the filament supplied by Sintron did not stick to the bear alluminium bed without slight heating (60C degrees). I discarded the first piece of plastic mess. Other than that it's the very first 3d printed object! Will buy some Kapton tape tomorrow and try with cold bed.

The bottom layer is a bit melted out to the side, but that's because something happened in the extruder, after a second it started feeding the filament properly.

Need to add some heatsink to the MOSFET though

HAPPY!

Congrats on getting your Sintron running. That is a very nice first print.

Thank you very much guys! Yesterday I followed your recommendation and attached the masking tape I had at home, but it's not blue, it's bege, like on the picture. Not sure if there is colour difference in properties, like temperature endurance. It seems my tape took one print okay, I printed endstop upgrade, but some thin plastic threads stayed on the tape.
And I think I have on my zero level hotend closer to the bed on one side and it lifts to the other side, I'll read through and fix that without Z probe. Seems that's very usual thing for everybody.

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Levon
Not sure if there is colour difference

Doesnt matter the color.
I used a few different tapes. I can say that none textured frog tape doesnt hold up well.

Blue painter tapes is good. Masking tape like what you have is good also.

And you print looks like your to low in Z on your probe offset.
The top layer looks like the nozzle grinded into the top layer of the print.

And yes if your lifting on one tower and grinding into the bed at another. Then your calibration is off.
I spend alot of time trying to use auto and calcs. But in the end manual calibration and test prints work.

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Levon
Thank you very much guys! Yesterday I followed your recommendation and attached the masking tape I had at home, but it's not blue, it's bege, like on the picture. Not sure if there is colour difference in properties, like temperature endurance. It seems my tape took one print okay, I printed endstop upgrade, but some thin plastic threads stayed on the tape.
And I think I have on my zero level hotend closer to the bed on one side and it lifts to the other side, I'll read through and fix that without Z probe. Seems that's very usual thing for everybody.

My experience with masking tape (painters tape) with general painting and not printer. White tape is the cheapest and tears easily. Blue tape is for marking errors in dry wall and defects on a new home during construction (blue is medium hold on surface medium priced). Green tape ie frog tape is the most expensive and holds well to the surface.

For 3D printing: I was using generic green tape and it works well on PLA and ABS and PETG. I would suggest NOT using white tape as it tears easily and the sticky stuff is cheap and makes it hard to remove from any surface if left on that surface for a long time.

Hello xile6,

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xile6
And yes if your lifting on one tower and grinding into the bed at another. Then your calibration is off.
I spend a lot of time trying to use auto and calcs. But in the end manual calibration and test prints work.

Can you please share further details how you did the manual calibration?

Thanks.

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gkr
Hello xile6,

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xile6
And yes if your lifting on one tower and grinding into the bed at another. Then your calibration is off.
I spend a lot of time trying to use auto and calcs. But in the end manual calibration and test prints work.

Can you please share further details how you did the manual calibration?

Thanks.

I moved the hotend to each tower.
I used the tower position from Escher 3D

Made shortcuts in pronterface. So my Z tower would be G1 X0 Y-70 Z5 F6000

Move the hotend to Z5 above each point. Then jog down till it passes the paper test.
Make a note of how much off it was if it was positive or negative.
Move to the next tower and do the same thing.
Which ever tower was the off the most, i would offset the other 2 towers by that amount and try again.
first round was X0 Y-0.5 Z0
did a test print and the rear (Z tower) was grinding into the bed but the front was printing find.
Ended up picking up the rear by offsetting the front. So it became X-0.7 Y-1.2 Z0
-0.7 is how much the Z was off on round two.

I just did this till i could print a 80mm square without a corner lifting or grinding into the bed. Also made sure all my belts where very tight.

Hi all,

Did a little bit of more leveling, seems have relatively flat coordinates. Did test print of this thing. Did not expect to have so many bridging threads in between the towers. On one hand I realize that there is a pressure in the PTE tube made by the extruder motor and it's not possible to cut it out quickly, but on the other I haven't seen that kind of hairy mess on others' examples... Is it normal on my print or I need to do better calibration of the extruder motor?
Actually I did not expect my printer will handle that big bridge of the object, but surprisingly it did the job perfectly!

Another question, how do you guys handle it when one batch of filament is finishing on the half way of your print, do you manually feed the new filament during the print so it pushes the old one and then goes into the hotend or there is more civilized method? I did it manually and had horrible filament feeding until new one made it to the hotend and huge gap with no filament at all in the base of the object so it's in very bad shape.

And last question. Is that only me who looks spellbound how printer prints all the way from the beginning to the end?

Would appreciate any observations if you see any other defects on the pictures that I don't see and can fix!

Thanks!

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Levon
Hi all,

Did a little bit of more leveling, seems have relatively flat coordinates. Did test print of this thing. Did not expect to have so many bridging threads in between the towers. On one hand I realize that there is a pressure in the PTE tube made by the extruder motor and it's not possible to cut it out quickly, but on the other I haven't seen that kind of hairy mess on others' examples... Is it normal on my print or I need to do better calibration of the extruder motor?
Actually I did not expect my printer will handle that big bridge of the object, but surprisingly it did the job perfectly!

Another question, how do you guys handle it when one batch of filament is finishing on the half way of your print, do you manually feed the new filament during the print so it pushes the old one and then goes into the hotend or there is more civilized method? I did it manually and had horrible filament feeding until new one made it to the hotend and huge gap with no filament at all in the base of the object so it's in very bad shape.

And last question. Is that only me who looks spellbound how printer prints all the way from the beginning to the end?

Would appreciate any observations if you see any other defects on the pictures that I don't see and can fix!

Thanks!

What speed did you print this at?
Temp and filament type?

The stringing is a bit to much. The extrude needs to be calibrated and your retraction speed probably up.
Its way to thick. Most stringing is thin like hair.
You need a good part cooler fan to do bridges if printing in pla. Other then that the bridging is ok.

When you need to replace filament you need to print and move it out the way of the print.
Normally print, lift Z5 and move X10, then you pull out the filament.
Put the new one in and make sure you push it through so it comes out the nozzle.
Then move it back into place and resume.

You can youtube "changing filament while printing."
Some people do this to get a multicolor print.

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xile6
What speed did you print this at?
Temp and filament type?

I was using the piece of filament Sintron supplied with the kit, since they had no word what kind of filament is that, I assumed it was PLA for the beginners.
I set the temperature to 200, it looked not too bad on the cube I did earlier. Maybe it's too much.
Speed is 30mm/s

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xile6
The stringing is a bit to much. The extrude needs to be calibrated and your retraction speed probably up.
Its way to thick. Most stringing is thin like hair.
You need a good part cooler fan to do bridges if printing in pla. Other then that the bridging is ok.

Yep thanks, I'll re-calibrate the extruder and will think on adding the object fan!

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xile6
When you need to replace filament you need to print and move it out the way of the print.
Normally print, lift Z5 and move X10, then you pull out the filament.
Put the new one in and make sure you push it through so it comes out the nozzle.
Then move it back into place and resume.

You can youtube "changing filament while printing."
Some people do this to get a multicolor print.

Thanks for the tips!

Edited 1 time(s). Last edit at 01/26/2016 07:21PM by Levon.

@Levon

If you still have the filament, burn it.
Take a lighter to it. If it burns and gives off a platic smell and black smoke its abs.

If it melts and kinda has no smell or smells sweet. Then its pla.

Some say do a bend test, abs bends vs breaks, but i couldnt get that to work with filament that was labled. But the burn test doesnt lie.

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xile6
@Levon

If you still have the filament, burn it.

Good idea, I'll collect leftovers and will try that out.
For PLA you recon 200 degrees 30mm/s is okay?

I ordered 1kg spool of PLA filament on ebay, still on its way, they say it's for 200-250 degrees so I decided to go with 200 for the Sintron one as well...

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Levon

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xile6
@Levon

If you still have the filament, burn it.

Good idea, I'll collect leftovers and will try that out.
For PLA you recon 200 degrees 30mm/s is okay?

I ordered 1kg spool of PLA filament on ebay, still on its way, they say it's for 200-250 degrees so I decided to go with 200 for the Sintron one as well...

Yea i normally do 195 for pla and 230 to 240 for abs on both my kossel and prusa printers

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Levon

For PLA you recon 200 degrees 30mm/s is okay?

I ordered 1kg spool of PLA filament on ebay, still on its way, they say it's for 200-250 degrees so I decided to go with 200 for the Sintron one as well...

I had different spools of PLA Filament from different Providers with extremely different behaviour.
Some PLA I had to print at 15mm/sec, 225°C and it still was extremely hairy - no Chance to solve this sith retraction length or Speed
I now have PLA which prints at 195-210°C (depending on print Speed) max. speed about 35mm/sec - absolutely no stringing...


you just have to try....

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Sir_Death
I now have PLA which prints at 195-210°C (depending on print Speed) max. speed about 35mm/sec - absolutely no stringing...
you just have to try....

Could you PM me your source? I'm usually use ebay and there are not too many Australian sellers out there... At least I might look here in Sydney for the brand you have. Thanks!

I print with PLA at 200-215 C (depends on object fan is on or not). Have just a minor stringing (most of them when slicer forget to do retracts where it should).

My print speeds are:
60mm/s for perimeters,
42mm/s for external perimeter,
90mm/s for infill,
300mm/s for idle moves.

When I used 1m bowden tube I set 8mm retract length at 50mm/s speed. Now I halved the length of the tube (by moving extruder motor to the middle of Z axis) and 3.5mm retraction length seems is enough for me.

The stringing increases when: temperature is higher and/or retraction is lower. I did not noticed the correlation to printing speed actually.

P.S. And I have to mention that I replaced the throat to a one with PTFE tube inside (which goes to the nozzle). This kind of throats tends to leak more than just metal one, so theoretically pure metal throat needs shorter retracts than I use.

Edited 2 time(s). Last edit at 01/27/2016 05:11AM by GrAndAG.

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xile6
@Levon

If you still have the filament, burn it.
Take a lighter to it. If it burns and gives off a platic smell and black smoke its abs.

If it melts and kinda has no smell or smells sweet. Then its pla.

Some say do a bend test, abs bends vs breaks, but i couldnt get that to work with filament that was labled. But the burn test doesnt lie.

Problem is: If you leave PLA out or ABS out too long in the elements and not in air tight container they both become very brittle. But the burn test is the best. If it smells sweet like maple syrup its PLA.

I wanted to upload a configuration sketch to the arduino but it gave a lot of errors. So I went through the trouble shooting guide and ended pressing the reset button with something made of metal. Then I smelled fried electronics and the lcd went out. The arduino was not being recognised anymore when connected to the ramps. Also it would get very hot like not being able to touch hot underneath the arduino. Whenever I disconnected the arduino from the ramps it would again be recognised and I was able to upload again. But when connecting the ramps the arduino would not be recognised again and the LCD would just blink and go out again. Also the arduino would become extremely hot on the bottom again. What should I do now? I still haven't been able to print anything, I only had problems uploading stuff, though it did move in one part of the proces.

Hoping for some solutions. Or tips on how to find out what is damaged by doing what I did.

Ok so it appeared to be the stepper motor that got fried. Now for the final issue since I'm really stuck here. How come I can only upload sketches to the arduino when the ramps 1.4 is not attached? From the moment it's attached it gives errors in uploading while pronterface works fine. It's a real hassle disconnecting the ramps from the arduino every time I'm trying to configure something, it also isn't very good for the pins.
I've read stuff on forums of it maybe being a bad crystal?
Is there any way I can just leave the ramps 1.4 on there since I get really frustrated by having to disconnect it from the ramps 1.4 and no one else seems to have this problem, or did I miss something?

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Noitome
Ok so it appeared to be the stepper motor that got fried. Now for the final issue since I'm really stuck here. How come I can only upload sketches to the arduino when the ramps 1.4 is not attached? From the moment it's attached it gives errors in uploading while pronterface works fine. It's a real hassle disconnecting the ramps from the arduino every time I'm trying to configure something, it also isn't very good for the pins.
I've read stuff on forums of it maybe being a bad crystal?
Is there any way I can just leave the ramps 1.4 on there since I get really frustrated by having to disconnect it from the ramps 1.4 and no one else seems to have this problem, or did I miss something?

Buy a new board.
No telling what is messed up. But i can say it probably wont work anymore