Table of contents

Thursday, 2 January 2014

Velleman K8200 3D Printer assembly tips

I’ve finally received the Velleman K8200 3D printer kit… yeah!  :)  and I thought that I will share some tips & tricks useful during assembly. 

First of all – have a look into Velleman’s guide: 
http://www.k8200.eu/manual/building 
http://www.k8200.eu/manual/printing 

They also provide downloadable version of the guide. It’s a massive, 600+ pages PDF file: 
http://www.k8200.eu/downloads/0/assembly/assembly_manual_k8200_uk.pdf 

Ok, let’s start building this monster toy :) 

It took me about 8 hours to put the mechanics into one piece and then another 8-10 hours to solder everything together and calibrate it...
I must say that the manual describes well all the steps, processes, etc. The whole process is very good documented.
However, there are few moments that may discourage less experienced players… 


First, page 134 in the Assembly Manual – you have 2 vertical rods that are kept straight by 4 plastic elements. Then you have a Z axis carriage (built of 4 bearings). This was the trickiest part of the assembly, to make all these elements move smoothly...
If you tightened one of the plastic elements more than the other ones – the rods are not parallel anymore. These bolts slide into the plastic holders which can bend a little bit if tighten too much.
The other issue was with the carriage. Each bearing holder has 2 slots (not holes, just slots, so you see where this is going :) ) for 2 bolts, so the carriage has 8 bolts that need to be tightened – same story as with the rod holders – tightened too much and the plastic part slides out, making the bearing not in line with the rod...
After expressing myself in a poetic manner (I didn’t know my dictionary is so extensive :)) I sorted it out. Here is how you can do it: 
  • tighten firmly 2 bottom rod clamps but leave the top ones slightly loose
  • start sliding the carriage up&down, tighten all of the bearing bolts (you may want to keep your finger on the plastic element, preventing it from sliding out)
  • if you feel the carriage starts to twitch – loosen your current bolt a little and try tighten another one
  • when you tightened all 8 bearing bolts – tighten those holding the rods on the top
  • start over again until all the bolts are firmly tightened (as you won’t get it in one go)

Second, page 499 – don’t wrap the legs around the wire. This NTC has hair-thin legs. When you start wrapping the second leg – the weight of the wire will hang on the first leg. It is very easy to snap or rip the leg off. My tip: cut the legs leaving about 10mm, wrap the NTC to a piece of foam/cloth and clamp to a vice or use a ‘3rd hand’. You can clamp the 2 wires to the second alligator clip. Then simply solder the legs and the wires, slide the heat resistant sleeves and... job done :)  The screw holding the thermistor in place is about 6mm off the bead hole in the heater block so it will hold the thermistor by the solder joints. 


Third, page 505. I didn’t tighten the nozzle enough – I was afraid of breaking off the thread –  the nozzle/barrel are made of brass. After just 20 minutes of my first print – I got plastic coming out between the heating block and the white teflon barrel :/ (see my YT video below at 4m45s).   DON’T WORRY, it is very easy to fix (Velleman say it is IRREPARABLE):
  • heat the extruder to 200 oC and from now on DON’T TOUCH it, use some pliers to hold or ask someone to help you
  • remove 2 bolts holding the extruder (page 508)
  • unscrew the white plastic barrel (page 495)
  • take 2 wrenches and tighten the nozzle (page 505)
  • screw on the white plastic barrel (page 495)
  • put the extruder back into its place and tighten the 2 bolts (page 508)
Note: the heating block rotates over the barrel so you can rotate it if you can't reach the bolts. 


Fourth, page 567 – calibration. This is completely all over the shop. I don’t know why they have decided to put 4 adjusting knobs for all 4 corners instead of 3 points in a triangle shape. The other thing is that the heated bed (it is just a simple PCB with resistive traces) is not flat, it tends to sink in the middle. In my case it was 3mm difference between centre of the board and all 4 perfectly aligned corners (0.15mm from the nozzle). Quick trip to IKEA and I came back with these mirrors (http://www.ikea.com/ie/en/catalog/products/60074007/). I used clips to hold the mirror in place. After this change you need to be aware that:
  • the Z axis bolt (page 568) has to be adjusted as the nozzle needs to stop 3mm earlier
  • the printer settings must be changed to limit the printable area to 19x18cm (from 20x20 originally) – I took higher margin because of the clips holding edges of the mirror
  • heating takes more time (I have it set to 58 oC and it takes about 15 minutes to reach it in a warm room (+23 oC))





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106 comments:

  1. Thought of using a water bottle with a piece of rope at the end of a wrench for the correct tughtening torque on the nozzle.

    By weighing the water bottle and a bit of calculation I can get the right amount of torque.

    ReplyDelete
  2. Hi, thanks for useful advices :-) I am still on the way to build my K8200... anyhow, I have a question, I saw on video, that you have something attached to the connection of the heated bed, is it some kind of cover, or connector?
    Peter

    ReplyDelete
    Replies
    1. These are screw connectors soldered in the place for the wires.
      I have done it in case I will have to replace the bed for a different one without overheating the ribbon cable as it is delicate and I'm not looking forward to replace it or stitch it in a critical/bendable point.

      Delete
  3. Re torque setting I used a ring spanner with a bag at the end containing the calculated weight to give the correct torque. No probs so far.

    Any ideas to satisfactorily make parts with undercut features - ie a form where the diameter increases. I just get filaments hanging off.

    ReplyDelete
    Replies
    1. If possible, I flip/rotate the object around to prevent such situations.
      If not - I use "support material" feature in the Slic3r settings. By default is when the overhanging part is less then 45 degrees (it is adjustable).
      Also - you may try decreasing the extruder temperature. My setup is 190C and have no issues with flat bridges as long as 12-15mm (you can see it in one of my other posts - the main board mount). If the filament is too hot it will not be cooled fast enough by the fan. However, if you set the temperature too low - it may not stick properly to the previous/surrounding layers...

      Cheers,
      LJ

      Delete
  4. looks good, are you satisfied with your purchase overall, and would you have any suggestions to somebody considering this as their first 3D machine?

    ReplyDelete
    Replies
    1. Yes I am. The price (€700) / build quality ratio is good and the prints are ok. If you like mechanics/assembling stuff - definitely go for it :) but if you want just simply download/create an object, click 'print' and forget about it - this will not be for you. The printers are not maintenance free as standard inkjet/laser printers... from time to time you get something wrong, level the bed again, grease the rods, unclog the nozzle, etc., etc. :)
      After few months of playing I'm quite happy with the results, you have tons of options to fiddle with to get satisfactory results.
      The printer is a bit noisy, especially on fast travel movements (can be change in the settings) and during the infill part (I use honeycomb type) and it shakes my desk a lo but then, if you reduce the speed - it will take ages to print the object.
      Once I've done a comparison between quality and speed (I will post the results soon) and to print the same cone (1cm in diameter and 1cm height) it took from 3 minutes (0.40mm layer, fast/loud print) to almost 30 minutes (for 0.15mm layer height).

      Cheers,
      LJ

      Delete
  5. I am considering buying a K8200 printer - but my wife is concerned about the noise!
    Could you give some comparative examplesof the noise level? e.g. How much noisier/quiter is it than an impact printer?

    ReplyDelete
    Replies
    1. Hi, the printing is not that bad but the fast movements are the loudest noises. This can be changed in the settings - how fast to travel between points, printing speed, etc. It will reduce the noise level but it will not eliminate it. I couldn't sleep having the printer running in the next room.
      The other thing are vibrations when the infill part is printed. I use the honeycomb infill and it shakes a heavy office desk a lot. This may make another source of sounds spreading through your floor/ceiling. It is definitely louder than a inkjet printer. And most of the time it sounds like someone who can't play a violin :)

      Delete
    2. Hi, Thank you for your very prompt and helpful reply!
      If I get one I think I may have to use it in the garage!

      Delete
  6. Hi

    Thanks for you information Blog and video
    Is the driving software dedicated to the machine as I hope there would be opportunity to tune parameters.
    I have a friend who makes his own finer bore nozzles for his Ultimaker and uses CURA software to create the print files. It requires the parameters to be adjusted. The results are super and viable for finishing to acceptable model making standards.

    I am interested in making very much smaller pieces and therefore would be interested in you views regarding changing belt drive ratios by adaptation, to achieve a smaller incremental motion with a head fitted with a finer nozzle 0.18mm diameter. A factor of ten times smaller, is the area of interest. Adding gears to reduce the stepper motion would be required . The size of the model could "up scaled" to compensate for the gear reduction. ie 200mm max size prints 20mm model size Could you express an opinion of whether or not the software might cope with a change of parameters. You opinion is valued without obligation of course.

    ReplyDelete
    Replies
    1. Hi,

      This is great that someone is actually reading/watching it :)

      To get my idea printed out I use 3 pieces of software:
      - Google SketchUp to design the object (but you can use any other app that has capability to export the object to .stl file format)
      - Repetier to load the object, position on the bed, etc. (here you have all the printer's settings - communication with the printer, bed dimensions, nozzle diameter, temperatures, feed rate, park position, etc. - all this says to the printer how to behave, when to switch of motors, temperature and so on. All this settings will be included in the g-code file generated.
      - Slic3r to slice the object into a printer friendly format (it is basically a text file with coordinates/actions for the printer/nozzle). Here you have tons of options to choose from: layer height, how many solid walls you want, how many full bottom/top layers, infill type/density/angle, different speed settings (when moving around, when printing walls, infill, top/bottom parts, bridges, gaps, first layer, etc...), support (for overhanging elements), filament thickness (ex. 3mm), extruder/nozzle temperatures for first/other layers, cooling (fan speed range, when to turn it on/off) and also you can insert your custom g-code... (let say you want to do some weird movements or lift the z-arm or change the temperature or retract the filament....).

      In relation to making small items - the software will cope with it, the printer won't...
      The smallest item I have printed was a 5x5x5m object... I had to reduce the speed + add a loooooong waiting time between the layers to allow the PLA to cool down. Otherwise it will be just a soft/melted ball of PLA.
      I'm using 0.5mm nozzle with 0.2mm layer height and on the thermal camera I was able to see that when the nozzle extracts the PLA - the 3-4 layers below are getting hot enough that you would be able to deform/leave a mark with your fingernail...

      Delete
    2. LJ
      Thanks for your quality reply.

      The Repetier software is very good, Another freebie package is CURA from http://software.ultimaker.com/ it fulfils both slicer and manipulator roles in one package.
      It might work for you to?

      My associate uses it on the Ultimaker with 0.25mm nozzles. I like the Vellman machine a lot because of it's robust space frame system which offer easy adaptability.
      I wondered about using NEMA 17 Steppers with 5:1 built in gear reduction to facilitate fine resolution. in all the X-Y axises
      I am a licensed user of Solidworks so can create models "Just like the real thing".

      As a company we seek in-house facilities cheaper than the likes of Shapeways who charge high prices for the large stuff we model. A single cab unit off a 1/32 scale locomotive was costed by Shapeways as £365. We made it for a few pounds and 19 hour print time.

      In the past I was lead to believe that FFF/FDM was not good enough. I was mislead. We are now able to produce large models very cheaply using the method and the results are robust and good enough for use in the model product after a bit of skilful hand finishing with car spray primer and fine oxide paper. We wish to use the same process for small items to get the functionality and low cost.

      Your warning on cooling time is noted for small items.
      I am encouraged by what you have said and will look at the Vellmen again.

      Thank you so much.

      I would have sent you some model images but there is not a facility on here. An open access site could give us problems.

      Delete
    3. Thanks, I will give CURA a try.

      Delete
    4. My Velleman K82000 is purchased and arrives to day. £499.99 from Maplin.

      Delete
    5. Wonderful news :) and Congrats!
      Please let me know if you stuck however, Velleman's manual describes all the steps very well.

      Delete
  7. You mentioned (somewhere) using an IKEA mirror as a platform as it prevented sagging. Please would you remind me of the location of the information or the IKEA part number?

    ReplyDelete
    Replies
    1. Here you go: http://ljwinkler.blogspot.ie/2014/01/velleman-k8200-assembly-tips.html
      The mirror was mentioned in the "Fourth" section

      Delete
  8. I have found your tips video - part 1 - on YouTube. I there a part 2?

    ReplyDelete
    Replies
    1. Hi,
      There is no part 1 or 2...- this is the only video I've recorded so far in relation to the printer.
      Cheers

      Delete
    2. Hi
      I have (nearly) completed the building of the printer.
      The tempurature sensor /thermocouple shows a resistance of 125 (on the 200k range) in a room temperature of 19 degrees C whilst the instructions say it should be between 70 and 100.
      Is this still ok?
      Regards

      Delete
    3. I have completed the printer.
      Spent a week configuring and adjusting it.
      I am trying to print the cover as suggested but I get an error message - " Temperature is reset. Set it before restarting"
      I cannot find where this error is!
      I have tried turning everything off and reloaded all the programss and files.
      Where should I look?

      Delete
    4. Try your luck at the Velleman Forums: http://forum.velleman.eu

      Delete
  9. What type is the NTC you have? They have now 2 types: one tiny one and the newer that looks like a resistor (or more like 1N4148 diode) with legs on both sides.
    125k means you have pretty cold in your room :) but the good news is that is not shorted.
    Please check two things:
    - does it change the reading while poking the unit (I assume you have mounted it on the block)
    - does the reading go smaller when you heat it up? Even touching should make a difference.
    I will measure mine tonight.

    ReplyDelete
    Replies
    1. I appear to have the tiny one - it is about 1.5mm long and both legs come from the same end.
      Yes the reading changes to about 85 if I hold it between my fingers (about 28 degrees C)

      Delete
    2. Yes, same one...
      It has 130k in about +20C and drops to 80k when heated to +30ish.

      Delete
    3. I have completed the printer.
      Spent a week configuring and adjusting it.
      I am trying to print the cover as suggested but I get an error message - " Temperature is reset. Set it before restarting"
      I cannot find where this error is!
      I have tried turning everything off and reloaded all the programss and files.
      Where should I look?

      Delete
    4. At this point I can think about 2 reasons:
      - is your thermistor connected properly? can you see current temperatures in the application (I'm assuming you are using Repetier-Host V0.84? - it should be on the Manual Control tab).
      I can play around with the temperatures (bed and nozzle). You should see there your ambient temperature (15-25*C). I started by holding the extruder with my hand and setting up the temperature to 40C - it doesn't heat very fast so you shouldn't burn your finger :)
      - the other thing is: there are 2 setting for the temperature: one in Printer Settings (under "Printer" tab - that's the default temperature), the 2nd one is in Slic3r settings, Filament Settings tab (First and Other layers temperatures). but this shouldn't cause any errors... if you have the temperatures different the printer and press 'print', the extruder will heat up to your 'printer settings' temperature, then the printer will initialise itself (x-y-z home), then it will wait until Slicer temperature is reach and it will start printing...
      - also... I just found on Google that reflashing the firmware helped in this case (not the same printer, but the same board and issue).

      Delete
    5. Thanks - I will check these things .
      Which firmware are you refering to?
      (If this works I will owe you another donation!!)

      Delete
    6. I was thinking of "Firmware_k8200_marlinV1" (or V2 if you have the LCD). You can download it from: http://www.k8200.eu/support/downloads/
      And here is the manual how to do it: http://www.k8200.eu/manual/printing/?c=007

      Delete
    7. There was a mis-match in the heated bed temperature in the Slicer settings!
      It is now printing, but there does not seem to be enough PLA coming out of the nozzle.
      The print has 'holes' in it - lots of them!
      What do I need to do to find the cause and cure this?
      (Donation made!!!)

      Delete
    8. Thank you very much!

      In relation to your problem:
      - not enough/too much force on the extruder spring nut
      - temperature is too low (I have set to 190C) but depends on PLA I need to step it up to 200C. If the temperature is too high you will have hair/strings between elements
      - play with the Extrusion multiplier in the Slic3r settings (Filament settings tab) - I found 1.15 working great in my case

      Delete
    9. I will try varying the force on the extruder spring nut - Is there an optimum amount of force that the spring should exert?
      I will also experiment with the temperature.
      Do I need to increase or decrease the Extrusion multiplier in the Slic3r settings (Filament settings tab)? (I guess increase)

      Delete
    10. Yes, increase to get more filament extruded.
      I have the nut tighten approx half way through. But I'm still able to pull the plastic part with my finger to insert the filament.
      Also, this may help: http://instructables.com/id/How-to-calibrate-the-Extruder-on-your-3d-Printer/

      Delete
    11. Thanks
      I will experiment tomorrow - and probably have a lot more questions for you to answer!

      Delete
    12. I am pleased to report that I now have a very good looking cover for the PCB!! Thanks - is was the pressure of the spring which was much too high!

      I want to design small parts (for bicycles) but I am having difficulty finding programs which output the correct file format for the Repetier software. I found a plugin which said it would produce the correct file format but when I tried to download it my machine anti-virus protection said the website was dangerous and a known source of virus infections!

      Which programs do you recommend (for Windows 32-bit) to design parts and convert them for use on the machine? I thought I read it somewhere in your blog but (as usual) I cannot find it!

      Delete
    13. I recommend Google SketchUp: http://www.sketchup.com/download
      Once installed, go to Window / Extension Warehouse and install "SketchUp STL" - this will allow you to import/export STL files.
      Also, I highly recommend installing CleanUp3 plugin - it cleans imported file :) - when you import a file (.stl) you will notice that SketchUp creates tons of triangles (even simple object as cube can have more 'walls' than expected) - it optimises (sometimes not) the object.

      I've used SketchUp for all the parts I've created so far. Some of them you can find here: http://www.thingiverse.com/ljwinkler/designs

      Once you have exported your object to .stl - you can import it to the Repetier.

      Yeah, I need to create some kind of 'table of contents' here on the blog... :)

      Delete
    14. Hi (again)
      I downloaded your Frame clip and locking pin but when I tried to save the files it gave an error message " Invalid Public Key Security Object File - This file is invalid for use as the following : Certificate Trust List"

      Do you know what the problem is and how to solve it?

      Delete
    15. Hi,
      I just downloaded both files:
      - Bracket.stl (http://www.thingiverse.com/download:409393)
      - Pin.stl (http://www.thingiverse.com/download:409394)
      In Repetier I clicked on the "Load" icon (2nd icon, next to the Connect one) and I've selected the file... Loaded without any issues.
      Can you download/import other .stl files?

      Delete
    16. The problem was that I was trying to do download the files to my desktop pc (which does not have Repetier on it instead of my laptop (which I use to run the printer) which does have Repetier on it!

      I will get there - eventually - apologies for all the idiot questions!

      Delete
    17. Did you try opening on your desktop? According to: http://filext.com/file-extension/STL# the extension is also used by other apps so maybe your Windows didn't recognise it as CAD stl file (because you didn't associate it with Repetier) but as Certificate... thing instead?

      Delete
  10. Hello! Do you use small radiators for driver's chips? I heard that this will prevent skipping steps (among others reasons).

    ReplyDelete
    Replies
    1. Hi.
      No, I don't - I've checked the temperature on a thermal camera and the temperature varies from 75-85C (depends on the ambient temperature) so it is still 40-50C below the limit. So far, the longest print took me just over 9 hours - no issues at all.
      If you are going to install radiators - don't use the cheap ones with sticky pads that look like white, double sided foamy stuff - in my case it wasn't transferring heat at all :/ I used one on RaspberryPi and the difference was 35C! The chip was 90+ with the heatsink being relaxed at 60C :) It can cause more damage than help.

      Delete
  11. Hi,
    when you adjusted the layer height in slicer did you slow down the extrusion speed somewhere? my prints are extruding too much filament.
    great work BTW
    Thanks

    ReplyDelete
    Replies
    1. Hi,
      I have 1.15 extrusion multiplier in Filament Settings tab.
      Also. in Printer Settings tab => Advanced menu I have all 4 Extrusion width boxes set to '0' (auto).
      Hope it helps.
      Thanks.

      Delete
  12. Dear Winkler,

    I would like to ask your advise for the following situation:
    I am having an error "variable is not of type Wx:Window at C:/PROGRAM-1/Repetier-Host/Slic3r/lib/std/Slic3r/GUI.pm line 204, when i select Slic3r configuration into Repetir-Host version 0.84. My operating systems is Windows 7 Home Edition.

    Thank
    Best Regards,
    José

    ReplyDelete
    Replies
    1. Hi José.

      I have found something that can help: https://github.com/alexrj/Slic3r/issues/908
      The issue with Slic3r is that it does not support non-Ascii characters in Windows user name. I'm assuming your user contains 'é' in José?

      Cheers,
      LJ

      Delete
    2. Hi Winkler.

      Thank you for your answer.
      I have changed to Repetier-Host V0.95F — I was using V0.84 because is the manual's version — and error disapearier.
      Meanwhile, I am having another error mensage: "Error: checksum mismatch Last Line: 622 — Resend 623".
      Could you help me?

      Thank you
      Best regards,
      José

      P.S.: I would like give you a donate. How can I do it?

      Delete
    3. Hi José,

      I Googled your problem and I found 3 possible answers:
      - someone reported crappy USB hub / long USB cable that the transmission gets corrupted. They advised to shorten the cable/connect directly to your laptop/PC. Sometimes, restarting/reconnecting the printer helps temporarily.
      - Marlin's buffer can't handle long lines. The suggestion was to shorten the number coordinates. I'm not sure what you have but something like this: "G1 X101.84263959390863 Y58.296954314720814" is definitely too long with too high precision (usually X101.842 should be ok).
      - V0.95F has a bug - yes, I can confirm that. I've installed it a minute ago and I'm getting the same error as you.

      Are you using Repetier for printing or you just slice it using it?
      On the K8200 support website they have configuration files for 0.84 and 0.90 only.
      I'm using V0.90C (http://www.repetier.com/download/) and have no issues with it however, I just slice the object using Repetier and then I send the g-code to RaspberryPi which controls the printer remotely.

      Thanks for your support - the Donate button is right on top of this page.

      Thanks,
      LJ

      Delete
    4. Hi Winkler,

      Thank you for your reply.
      My USB cable is short: 300 mm.
      My number coordinates are short, example: G1 X89.471 Y100104.375 E5.98979 F3600
      I am trying print the "MAKE" magazine logotype — MAKE_Robot V6.stl
      I am using Repetier for print.
      I am going to try Repetier V0.90C.

      Thank you,
      Best regards,
      José

      PS: I am trying donate you but my credit card is invalid by PAYPAL. What is happening?

      Delete
    5. Hi Winkler,

      I have installed the Repetier-Host V0.90C. But I can not run Slic3r's setup — Manual page's number 574.

      Thank you,
      Best regards,
      José

      Delete
    6. Hi,

      What is the error message you are getting?
      Have you completely uninstalled the previous Repetier or just overwrite the installation with the 0.90C?
      You could also try installing the Slic3r manually - the latest version (currently 1.0.1) can be downloaded from here: http://slic3r.org/ (please make sure you have downloaded the correct version (32 or 64 bit).

      Also - here are the links for GCode documentation (it may be useful for others):
      - http://en.wikipedia.org/wiki/G-code
      - http://reprap.org/wiki/G-code


      Regards,
      LJ

      Delete
    7. Hi Winkler,

      I am not getting any error message only the setup configuration window doesn't start.
      Yes, I had completely uninstalled the previous Repetier and then install version 0.90C.
      I am going to follow your advise and install Slic3r manually.
      Thank you for GCode documentation links.

      Best regards,
      José

      Delete
    8. Hi,

      Also, try specifying the paths manually in Repetier: Slicer tab, then on your right hand side you have Slicer dropdown menu (you can select Slic3r or Skeinforge). Pick Slic3r and then click on the Manager button. By default you will have these 2 boxes empty and the Slic3r Version dropdown should be "0.9.9 or higher". Use the Browse buttons to select the path to the location where you have installed Slic3r.
      Also, try running Repetier as Administrator (right click on the shortcut and select "Run as administrator"). Maybe in your case it requires admin rights to save some config files in the Program Files folder?

      Regards,
      LJ

      Delete
  13. Hi Winkler,

    I am using Repetier-Host version 0.90C.
    I can't change the configuration folder from "José Joaquim" to "JoseJoaquim" without portuguese characters.
    I have changed my user name from "José Joaquim" to "JoseJoaquim". I have erased all files of Repetier and slic3r but I can't change the configuration file.
    Please help me.

    Thank you
    Best regards,
    José

    ReplyDelete
    Replies
    1. Hi,

      I wonder if only the username has changed or also the user's folder (in C:\Users\)?
      Could you try the following:
      - create a new user, let say "reptest" (one word only)
      - login to reptest and install Repetier
      - try if it works

      On my Windows 8 I have the following installation folders:
      - Repetier-Host in its default installation folder: C:\Program Files\Repetier-Host
      - Slic3r in its default installation folder: C:\Program Files\Repetier-Host\Slic3r
      - Slic3r settings1: C:\Users\USERNAME\AppData\Roaming\Slic3r
      - Slic3r settings 2: C:\Users\USERNAME\AppData\Local\RepetierHost

      Apart from the above, try running slic3r.exe (you may try slic3r-console.exe as well) in C:\Program Files\Repetier-Host\Slic3r - these open the same configuration window as you are trying to open from Repetier.

      Also, what about your firewall settings? I just played a little with it on a virtual machine and if I set up firewall (for example, ZoneAlarm) too tight, it limited Slic3r's privileges and the window didn't open.

      Regards,
      LJ

      Delete
    2. Hi Dear Winkler,

      I created a new user — reptest.
      I uninstalled the old Repetier installation.
      I login with new user.
      I installed Repetier-Host version 0.90C.
      And finally I had access to "Slic3r - configuration".
      Thanks to you Winkler. You deserve a donate.

      Best regards,
      José

      Delete
    3. Hi winkler,

      I had download the file "k8200_pla_standrad".
      And after I have loaded to the Slic3r.
      I sliced the file "MAKE_Robot_V6.stl" and I got the G-code.
      Then I ran and I have got the following error mensages:
      Error: Line Number is not Last Line Number+1, Last Line: 0
      Resend 1
      Printer Layer 1 of 97
      Error: checksum mismatch, Last Line: 186

      Could you helpe me?

      Thanks.
      Best regards,
      José

      Delete
    4. Hi,

      Have you tried slicing/printing anything else?
      I found a similar problem here: https://github.com/ErikZalm/Marlin-non-gen6/issues/7
      Seems that after reflashing the firmware the problem stopped.
      You can download it from K8200 website: http://www.k8200.eu/support/downloads/
      To update the firmware please follow the instructions: http://www.k8200.eu/manual/printing/?c=007

      Also, on another forum (http://www.soliforum.com/topic/3022/errorline-number-is-not-last-line-number1-last-line-4/) they say you can ignore the messages and to completely reset it "disconnect repetier, exit repetier, fully power cycle the SD (external power + usb), open repetier, connect.."

      And... on the K8200 download section (top of the page) I just noticed, they have a "Custom Repetier Host" file link. They say that "No more troubles with driver installation or fiddling with settings and config files." - I will give it a try next week, it may be worth of trying.

      Cheers,
      LJ

      Delete
    5. Hi Dear Winkler,

      I am trying print this g-code:
      G28
      M190 S50
      M109 S190
      G91
      G1 X50 Y75
      G1 X50 E250
      G1 Y50 E250
      G1 X-50 E250
      G1 Y-50 E250

      But sometimes the extruder goes fast sometimes goes slowly, with the same g-code.
      Is not danger to reflashing the firmware — could damage the electronic board?
      Could you send me a file that you know is good?

      Thank you
      Best regards,
      José

      Delete
    6. Hi Jose,

      According to your commands and gcode definitions you are executing the following:
      G28 - homing the X-Y-Z axis
      M190 S50 - waiting until bed reaches 50 degrees
      M109 S190 - waiting for extruder to reach 190 degrees
      G91 - setting relative positioning
      G1 X50 Y75 - moving X by 50, Y by 75 and then the following 4 lines just draw a square basically
      G1 X50 E250
      G1 Y50 E250
      G1 X-50 E250
      G1 Y-50 E250


      One of my prints was the nozzle: http://www.k8200.eu/downloads/files/downloads/k8200fannozzle.gcode.zip
      This is ready to be printed g-code provided on Velleman’s website – it worked on my printer without issues.

      I compared the gcode to your and they use much more actions before start (they also use absolute distances… so they move from 50 to 60 but you move 10 from your last position – it doesn’t matter really, the output should be the same):

      M190 S50 ; wait for bed temperature to be reached
      M104 S190 ; set temperature
      G28 ; home all axes
      G90 ; use absolute coordinates
      G21 ; set units to millimeters
      G92 E0 ; set position
      M82 ; use absolute distances for extrusion
      M109 S190 ; wait for temperature to be reached
      G1 E10 F400 ; prime the nozzle
      G90 ; use absolute coordinates
      G21 ; set units to millimeters
      G92 E0 ; set position
      M82 ; use absolute distances for extrusion
      G1 F3900.000 E-5.00000 ; Set Feedrate to 3900, retract extruder
      G92 E0 ; set position
      G1 Z0.300 F12000.000 ; lift Z axis, set Feedrate to 12000
      G1 X123.640 Y123.240 ; the printing starts (next 75k rows)


      And they end the code with:
      G92 E0 ; set position
      M104 S0 ; turn off temperature
      G28 X0 ; home X axis
      M84 ; disable motors


      Flashing anything is always a bit risky process :)
      Power interruption, etc. may affect the flashing process however, I have flashed it few times (even with the latest V2 supporting the LCD) and it works. Haven’t killed it :)


      Cheers,
      LJ

      Delete
    7. Hi Winkler,

      Thank you for yours explanations (and your patience).

      I have tried the Fan Nozzle G-code and I have got many "Checksum" Error mensages and finally the serial connection breaks and the printer stops and Repetier disconnects.

      I have decided to reflashing the Firmware.
      Could you confirm me the file name: "Firmware_k8200_marlinV2" or "Firmware_k8200_marlinV1" ?
      Usally how much time delays the reflashing?

      Thank you.
      Best regards,
      José

      Delete
    8. Hi,

      Seems there is an issue with connectivity. Maybe the cable is too long, USB hub is poor quality, etc. or your system is mental :)
      Could you try this printer on another PC/laptop and using different cable - this will indicate where the problem is.

      Firmware V1 is currently installed on your board so you can re-flash it again. V2 supports the VM8201 LCD screen (http://www.k8200.eu/downloads/0/modules/assembly_manual_vm8201.pdf)
      Here is a manual about flashing the board: http://www.k8200.eu/manual/printing/?c=007
      However, if you have connectivity issues the update may fail as you won't have stable communication with the board.

      Cheers,
      LJ

      Delete
    9. Hi Winkler,

      Please confirm my printer settings:

      Connector: Serial Connection
      Port: COM11
      Baud rate: 250000
      Transfer Protocol: Auto detect
      Reset on Connect: Disabled
      Reset on Emergency: Send emergency command and reconnect
      Receive Cache: 63
      Use Ping-Pong Communication (Send only after ok)

      Thank you.
      Best regards,
      José

      Delete
    10. Dear Winkler,

      Good news.
      I haven't had more error mensages :)
      I am printing "k8200fannozzle.gcode" and didn´t get any error mensages.

      As you told me to do, I took away the laptop battery and the machine battery and the errors mensages disappear.

      Thank you very much. I glad to meet you.

      Best regards,
      José

      Delete
    11. Hi José,

      Hooray! :) Well done to you.
      And yes, your settings are ok: seems exactly what they recommend here: http://www.k8200.eu/manual/printing/?c=002

      Cheers,
      LJ

      Delete
    12. Hi,

      Sorry dear Winkler but I have another problem.
      I think the motors X and Y skip steps.
      I have tried to print a square and the layers didn't superimpose well — as you can see in the picture (I don't know how can I send you a picture).

      I have measured the calibration voltages:
      X - motor: 0.82 Volts
      Y - motor: 0.75 Volts
      Z - motor: 0.71 Volts
      Are these values acceptable or not? I have never changed them.

      Thank you
      Best regards,
      José

      Delete
    13. Hi José.

      The voltage defined by Velleman is 0.425V (http://www.k8200.eu/manual/printing/?c=002) but then, later on the page, they say you can increase it to 0.55V to increase the current on the stepper motors. You have it almost twice the value suggested and even now you are saying the printer skips some steps - I'd say it is mechanical problem: the rods are not parallel or there is some traction.
      Can you move the bed x-y freely by hand? It shouldn't take much force even with the belts on. Without the belts the bed should slide without touching it once you tilt the printer (from about 30-40 degrees).
      You could try aligning the rods and/or apply some lubricant on the rods.

      Regards,
      LJ

      Delete
    14. Hi Winkler,

      Perhaps I am not describing to you the real problem because I put off the belts and I sent the g-code to the X-motor without the belt. The motor starts to run but sometimes stops for a moment randomly.

      This is the G-code I am running:

      G21
      G28
      G91
      G1 F100
      G1 Z10
      G1 F1500
      G1 X10 Y50
      G1 X150
      G1 X-150
      G1 X150
      G1 X-150
      G1 X150
      G1 X-150
      G1 X150
      G1 X-150
      G1 X150
      G1 X-150
      G1 X150
      G1 X-150
      G1 X150
      G1 X-150
      G1 X150
      G1 X-150
      G1 X150
      G1 X-150
      G1 X150
      G1 X-150
      M84

      Please help me.
      Thank you.
      Best regards,
      José

      Delete
    15. Hi José,

      Hmmm, this is very simple G-Code and it shouldn’t cause any issues.

      I wonder if the electrical wiring is correct? For example, if the X-stop switch vibrates and the wires make a contact in random moments (it doesn’t need to be on the switch but anywhere down the line), then the printer may think it reached the home position?

      Also:
      - how did you generate this code? As far as I understand the code, you are just moving the X-axis left and right by 150mm multiple times.
      - how about some real gcode files (for example the one I have posted with the nozzle)? Do they print ok?
      - can you try the same code on a different pc/laptop?

      Thanks,
      LJ

      Delete
    16. Hi Winkler,

      Yes, it is a very simple G-code only to test the X-motor.
      I pull off the X-stop switch and I think that is an impossible switch's problem.
      I test all the connections and everything seems to work well.
      The G-code I wrote it on "NOTEPAD" is only to test X-motor.It goes 10 times right and left. The X-motor is free without belt.
      The problem hapenned also with the nozzle file. It didn't print ok. The different layers don't superimpose well.
      I am going to try in a different laptop.

      Thank you for your patience.
      Best regards,
      José

      Delete
    17. Hi Winkler,

      I tried the same code on another Laptop and the problem continues.
      I have changed the batteries position and plug the 3D printer to a wall plug without other machines. The problem continues.
      So many experiences I have done that I have found:
      When I change the motor velocity, from F1500 to F3000, the randomly moment stops decreases.
      And, when I wait 5 minutes between "Run Code" the randomly moment stops also decreases.

      The new g-code I run is:

      G1 F1500
      G1 X150
      G1 X-150
      G1 X150
      G1 X-150
      G1 X150
      G1 X-150
      G1 X150
      G1 X-150
      G1 X150
      G1 X-150
      G1 X150
      G1 X-150
      G1 X150
      G1 X-150
      G1 X150
      G1 X-150
      G1 X150
      G1 X-150
      G1 X150
      G1 X-150
      M84

      It's a simple G-code to test the X-motor without belts. The X-motor moves freely.

      Thank you.
      Best regards,
      José

      Delete
    18. Hi José,

      I have another ideas: :)
      1. The wiring to stepper motor is incorrect (swapped pins, etc.) but this makes no sense as it works sometimes…
      2. The stepper motor controller is faulty:
      a. You could try plugging the X motor to Y controller and changing your code to operate now in Y axis (as the code will need to control the Y axis now where the X motor is plugged in) or:
      b. you could try swapping the controllers on the main board – these are the small, raised boards next to stepper motor ports. As you can see on the 3rd picture here: http://ljwinkler.blogspot.ie/2014/01/controller-board-mount-for-velleman.html the X-motor controller is the last one (or the first one :) depends the way you are looking from J) you could try swapping it with Z axis or Extruder controller
      3. Also, set the voltage to 0.55V on the controllers – if you have it set too high and you are overloading them - they may have built-in protection that switches them off…
      4. The board/controllers are faulty – you can ask your local distributor or ask Velleman: techsupport@vellemanusa.com or support@velleman.be

      Cheers,
      LJ

      Delete
    19. Hi Winkler,

      I have changed the reference voltage from 0.825 volts to 0.620 volts and XX motor stops disappeared.

      Thank you for your help.

      Best regards,
      José

      Delete
    20. Hi José,

      Happy to hear that you solved the issue.
      My guess is that because of the overvoltage you were overheating the drivers so the safety feature turned the controller off - stopping the motor for a while.

      Regards,
      LJ

      Delete
  14. I have been having difficulty up loading the firmware.
    A friend suggested that USB cables are available with different wiring. How can I confirm which cable I haveis correct? Have you heard of any difficulty with USB cable types?.

    What is the function of the reset button on the upper right hand of the board?
    Does it erase the installed programme or merely reset the programme to the start?

    In the set up text in the manual there is reference to flashing LED. When attempting the down load what is the colour of the flashing LED. I have red and green flashing at certain times in the function.


    ReplyDelete
    Replies
    1. I am not able to set the baudrate on the COM3 port to 250000. The nearest settable value is 230400. The device manager on my Windows 7 Pro system says my device driver is up to date.

      Have read deeper into your blogg to others the sequence of LED appears to be indicating correctly from making the first USB connection, without power : LED5 Red & LED6 Green constantly lit.
      When power applied LED1 Green flashes twice.

      Another issue I have to resolve is the Baudrate on the Arduino programming software.
      It appears you can not set 25000 baud rate on that either. I have tried to set a common low value of 19200 but still I can not get any communication between the computer and the printer,

      Frustration setting in!

      Delete
    2. Hi Francis,
       
      Did you follow the instructions on: http://www.k8200.eu/manual/printing/?c=007
      I’d say the tricky part is to make to Arduino software/drivers running. Then you can’t forget about shorting the 2 pins on the board.
       
      A standard USB cable with USB Mini plug is fine. Not sure what your friend meant by that. The only thing I came across was a cable from some cheap-arse manufacturer who used just 2 wires to power-up the device (there was no need of communication so the cable was only providing power) – probably to save a fraction of a cent on production costs :)  Apart from that ANY cable should work.
       
      According to this http://reprap.org/mediawiki/images/9/9f/Schema_base.jpg the LEDs (top right corners, LD5, LD6) just show the communication. One is for Receiving data, the other one would be for Sending data. So that was correct, they should blink during flashing/printing/any communication with the printer.
       
      The reset button just resets the microcontroller – nothing fancy. Same as you would disconnect the power supply and connect it back again. It doesn’t clear the firmware or restart the printing job - it is very similar to a standard reset button on a PC. However, I’ve never used this button :)
       
      The reason you may not see 250k baud rate because your motherboard doesn’t support it (I don’t believe it but it may be the case) - please check in your motherboard's manual.
      You could try changing the COM port speed to 230400. It is the closest to 250000 and this should work (it is just -3.5% clock error).
       
      I have found on a Velleman forum (http://forum.velleman.be/viewtopic.php?f=48&t=10622) that if the software responds after you press the reset button, you need to change “Reset on Connect” to “Disabled” in printer settings.
       
      Cheers,
      LJ

      Delete
    3. Hi LJ

      Thanks for the confirmation of detail.
      I have followed the http://www.k8200.eu/manual/printing/?c=007 procedure.
      I am using a wire jumper on 2 pin.
      The serial port on the computer is using the FDI driver 2.10.0. 0.
      I am using a comunicationd USB cable.
      The printer appears as COM3 in the arduino software and a common value of 230400 baudrate is set on the computer and within the arduino software.
      All appears well upto the point where "Marlin" is complied and the upload started.
      The LED3 flashes a few time and the LED5 & LED6 flash alternately and then nothing.
      Effectively it hangs and the Arduino software never reports "uploading done".
      If I disconnect the cable the arduino software report "avrdude: stk500v2_ReceiveMessage(): timeout.



      I did note a thread relating to dry joints on the board on the Velleman forum and have resoldered the pins and checked the continuity from the board to the pins in the usb socket and all is well but I am still can not getting the computer and the printer to communicate.

      Please can you help

      Regards
      Francis



      Delete
    4. Hi Francis,
       
      I would suggest trying other laptop/PC as I recommended to other guys.
      Your current configuration may have some specific firewall settings, some app installed that block COM ports, something that re-configured the port, some libraries causing issues, etc…
      Connecting the printer to a different machine usually shows if the problem is with Windows/COM/Arduino/settings or with the printer itself.
      The upload (when the LEDs flash) takes about 10 seconds… and the LEDs blink constantly, and then you get the message “Done uploading”.
      Seems like the communication starts in your case (few flashes) and then it stops.
      This may sound silly but… have you selected the correct board (Mega 2560) and the correct port (according to your Windows Device Manager) in the Arduino software? Looks like the COM port is ok as you had few flashes but then… the board type may be incorrect (it can’t communicate/regonise the board) or the COM port baud rate is wrong and they ‘talk’ with different speeds.
      Also, you could try disconnecting the machine from the internet, then disabling/switching off any software running (antivirus, additional firewall, printer, fax, whatever, to keep the hardware connected to your laptop/pc as low as possible. For example, some energy monitors use ‘USB’ connectivity to send the stats (in reality this is just a simple USB2Serial converter) that may causing havok in the COM ports…
      Then of course, you would need to reboot windows to have all this app startup again.
       
      Cheers,
      LJ

      Delete
    5. Hi Lj

      I believe that I am have successfully up loaded the Marlin firmware by using a Laptop with XP as the system. I set 230400 baudrate on the arduino software and the serial port COM3 of the laptop. There is now obvious way to confirm that a successful installation has been achieved.
      This time around the laptop appeared to upload the firmware correctly and reported "Upload done". LED5 & LED6 flashed the entire time of the upload.

      At this point I have to thank you for your assistance.However I am less than happy with Velleman, who I contacted initially, merely to be told to use the forum. That approach is less than a quality solution. I am not inclined to recommend the machine to anyone on the basis that the technical support they offer is poor. None of the technical comments you have explained are mentioned in the manual and a fuller explanation of what was is expected to happen, is lacking.

      Now I have to get the machine running, axises driving. bed heating.
      I assume the repetitor software is my next step.?


      Delete
    6. Hi Francis,

      I'm glad you have resolved the issue :)

      Yes, installing Repetier would be the next step.
      You can download a nice package prepared by Velleman:
      http://www.k8200.eu/support/downloads/
      It is called: "Custom Repetier Host for Velleman K8200 3D Printer"
      It contains Repetier 0.95f + driver + config. It worked fine for me. No
      troubles during installation.

      And then... you need an object that you want to print :)
      You can design it in Google SketchUp (or any other 3D software that is
      capable of exporting .STL files) or you can download thousands of
      ready-to-be-printed designs from http://www.thingiverse.com/

      Cheers,
      LJ

      Delete
  15. Hi,
    after assembling my K8200 I tried to print...
    The connection looks good but Unknown command messages are shown in the log area.
    Manual control of the printer does not work and als printing an object is not possible...
    Please advice
    Jean Burtin

    ReplyDelete
    Replies
    1. Hi,

      Seems to me like a connection issue.
      Please check if the printer is detected by your PC/Laptop (you should see additional COM port, check the settings, speed, etc.)
      Also, I’d start again with the “Using the printer” manual: http://www.k8200.eu/manual/printing/, especially the “Connecting the printer” part: http://www.k8200.eu/manual/printing/?c=002
      They have very good step-by-step guide there. Make sure you have also changed Repetier settings.
      What Repetier version do you have? Guys from Velleman recommend V0.84 for Windows but they also have provided their custom version (a bundle with driver, etc.) that can be downloaded from here: http://www.k8200.eu/support/downloads/
       
      Cheers,
      LJ

      Delete
  16. Hi Winkler,

    I am back.
    I would like to ask you if it is possible to save a "Sketchup" file and load on "Slic3r"? If not, do you know any free 3D software that cloud do it?

    Best regards
    José

    ReplyDelete
    Replies
    1. Hi,

      Yes, it is possible. I'm using SketchUp 2014 for my designs and once the object is selected I use File menu -> "Export STL...". This creates the file that can be imported into Slic3r.

      Cheers,
      LJ

      Delete
    2. Dear Winkler,

      Thank you for your answer. I am using "SketchUp Make version 14.1.1282" and I haven't the option "Export STL" only the export options: "3D model", "2D Graphic" and "Get Pro 3D exporters".

      Best regards,
      José

      Delete
    3. Hi,

      Seems you need to install it from the Warehouse.
      I will give you a step-by-step tutorial in SketchUp 2014 (I believe the other version have similar menus).
      1. Open Google SketchUp and navigate to Window menu and then Extension Warehouse
      2. Search for "STL" - you will see bunch of plugins, one of them will be "SketchUp STL"
      3. Install it (you need to be logged in)
      4. Restart SketchUp.

      Delete
    4. Dear Winkler,

      It works! One more time thanks for your instructions.

      Best regards,
      José

      Delete
  17. hi nice documentation and tweaks ...
    i have decided to build a scratch built 3Drag/K8200 ... but the biggest doubt i had was that i could not find a BOM of the hardware, vitamins,etc ..
    the length of the Aluminum extrusions are available, but the type of extrusion has been tricky to find out .. i have downloaded a couple of files of the parts of the printer, but the detail of frame extrusions i have not been able to derive it ... pls could you tell me what aluminum extrusions are used to make the chasis/frame of the printer (2020, 3030, 4040 etc etc)

    thanks in advance

    ReplyDelete
    Replies
    1. On Vellemans forum i did find someone asked this question.
      http://modelltechnikdirekt.de/Saeulen-Profil-275

      Delete
  18. Hi, thank you for all the great info you've put here!

    I've assembled my k8200 and I've noticed the following problem: sometime during printing (today after more than 1 hour) the printer suddenly goes "into the wild" (i.e it seems it looses it's orientation/ actual position) and starts putting plastic in the wrong place.

    Have you ever encountered or heard of such a behavior?

    Thanks!
    Paul.

    ReplyDelete
    Replies
    1. Hi,
      Four things came to my mind:
      - I would check the voltage on the stepper motors (according to Velleman they suggest 0.425V (http://www.k8200.eu/manual/printing/?c=002) but it can be increased to 0.55V
      - Then the mechanics (does the platform move freely?)
      - However, you have printed for an hour without issues so the 2 above may not be the case... But... When I was printing with blue PLA (shiny, transparent-ish colour, not the normal, matt-kind of PLAs) the object started to shrink when the temperature dropped (it was about 10 layers height) and the corners got lifted up, causing the extruder hitting the object. Depends on the size of the object, the extruder knock it off the platform or got stuck while the stepper motor skipped few steps - then the print was offset by those steps... Does your printer print correct object but shifted along one/two axes?
      - or... the g-code got corrupted and now the printer prints random rubbish :) However, it would be very weird if the corruption happened only in x-y axes. In this case you would get x-y-z, extruder, fan, etc. randomness :)

      Cheers,
      LJ

      Delete
    2. Thanks LJ.

      I'll increase the voltage to 0.55 for all the motors (I have only increased it for the extruder motor because it had problems rotating). The platform seems to move OK. Also I will install a newer version of slic3r (I still have the old one that came with repetier v0.84), maybe that will help.

      I did not notice the extruder hitting the object even though it's quite wide (160cm diameter) and even though it did lift up just a little bit. But I think I did hear some weird noise (a kind of bang, someting I didn't hear until then) just before it started printing badly.

      Thanks,
      Paul.

      Delete
    3. No worries Paul,
      The extruder shouldn't have any problems with rotating:
      - you may need to adjust the stepper motor location (http://www.k8200.eu/images/manuals/k8200/building/images/009/069.jpg) as the gears shouldn't be too tight. I have a little gap between the teeth - you could easily stick a piece of paper between. I use teflon grease for the gears. I have also printed a cover (http://www.thingiverse.com/thing:217654) preventing any grease drops onto the board and a crank for the bigger gear (http://www.thingiverse.com/thing:160714).
      - make sure the spring for the bearing clamp (http://www.k8200.eu/images/manuals/k8200/building/images/009/047.jpg) is not tighten too much. I have noticed that if I had this tightened then on slower extrusion speeds the bearing compressed the filament and the hobbed bolt sunk into the filament and it couldn't extrude it anymore - it was game over for the print.

      In relation to the bang noise: check under the hotbed if none of the ribbon cables are in the way of the belts or other moving objects. If something got tucked then it could touch and hook onto the aluminium profiles.

      Cheers,
      LJ

      Delete
    4. I printed today another object. Everything went smooth. It took almost 5 hours. Good for building confidence in the printer! No bending, lifting or warping at the edges (it's a large object), so that's a nice surprise.

      So what I did was:

      - update slic3r
      - increase motor voltage to 0.55
      - adjust the extruder motor location as you said (still need to get some grease)
      - loosen the spring a little bit
      - align the x belt
      - shorten the ribbon cable going to the heated bet so that it would stay out of the way when moving
      - prayed :D

      Still need to print the first object that failed. Will try that next...

      Oh, I have a problem with the Z axis when I press "home". It goes down and when the microswitch closes the exrtuder goes back up a little bit (which is not good because that is not position 0). When I press home a second time the extruder goes down and stops when the microswitch closes (which is good because that''s were position 0 is). X and Y work as expected. Do you know what may cause this? Or is this working as designed?

      Thanks LJ!

      Delete
    5. Well done! :)
      In my printer, the Z axis goes down on full speed, it hits the microswitch, goes up by few millimetres and then goes down again at 30% speed until it hits the microswitch again. And that's the position 0.
      Also, before printing it homes itself again doing the above but if it is in position 0 already, it just goes up few mm and down slowly until it reaches the switch.

      Also, try reflashing the firmware (http://www.k8200.eu/support/downloads/)
      You can try both, Firmware_k8200_marlinV1 or Firmware_k8200_marlinV2. The V2 version supports additional LCD and SD card reader. I'm using V2 so the behaviour may be different in V1.
      Here you can find how to update the firmware: http://www.k8200.eu/manual/printing/?c=007

      Cheers,
      LJ

      Delete
    6. Hi LJ,

      Uploading V2 firmware solved my home z problem. Thanks!

      Delete
    7. You are more than welcome :)

      Delete
    8. Unfortunately, for that same object I keep having the shift on X axis problem. It seems like it's happening at approximately the same height.

      Not sure what to do next...

      Delete
    9. Hmmm, what about the object itself?
      - is this your design? is it "closed" properly (Repetier will tell you if the object is not manifold).
      - if the object is downloaded, try downloading it again (I know, stupid but it may work :)
      - after slicing - how does it look when you flick through the layers/range in Repetier?
      - you could also try scaling it down to 50...33% and printing again. If the same thing happens in the same location - the object may be corrupted
      - try restarting the Repetier and importing the gcode (not the STL) - it will show you the sliced object - does it look ok?
      - or... there is a mechanical issue with the printer, that at this specific height + XY movements the cables got tangled or something...

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    10. Thanks LJ for the suggestions. It finally worked! It's an object I designed myself (and the main reason for which I bought the printer) Here is what I've changed:

      - lowered speed for non print moves to 100 mm/s
      - lowered gap fill to 20 mm/s
      - put a big fan in front of the motor driver circuits

      I don't know which one of these helped (maybe all of them, maybe none and I was lucky) but I suspect that the motor driver chip for the X axis got to hot

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  19. Hello,Lots of useful information here. We are still building our K8200 and have just got to the hotend. We used a torque wrench to tighten it but we notice that the Oval Aluminium bracket on the hot end is still loose and can be turned?
    Is this normal or do we need to tighten a little more. I am a bit nervous of this as there seem to have been multiple problems with overtightening the hotend. Any advice appreciated?
    Thanks
    Martin

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    Replies
    1. Hi Marin,
      Yes, that's normal.
      As you can see on this photo: http://www.k8200.eu/images/manuals/k8200/building/images/019/012.jpg
      the aluminium part sits snugly on the white spacer but it can't be tightened to anything.
      This is to allow rotating the nozzle-heaterblock-nylonbarrel component while attached to the extruder mechanism to allow the wires to run freely (http://www.k8200.eu/images/manuals/k8200/building/images/019/041.jpg).
      Check the orientation of the white spacer - the wider end should be on top so the aluminium part will push against it when you tighten the 2 vertical bolts.

      Cheers,
      LJ

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