New Mini-Kossel Setup Help

Hello. After struggling with this new build for days I am throwing in the towel and I could really use some assistance please.

I have a MiniKossel running on Arduino 1.0.5, RAMPS 1.4, Slic3r 1.1.7, and MacPronterface Mar 10, 2014.

For the life of me I can not get the printer calibrated and configured correctly. I am having these issues:

1. Hot End Fan will not enable automatically
2. Loading the 10mm cube test object will not print - my printer goes through the G29 autolevel procedure then does not heat up the hot end then then moves the hot end off the back of the printbed.
3. I can not get the printer properly calibrated - Tried and tried and tried - when I try to use OpenSCAD and the Kossel1515 model I do not get results that work - my printbed is 180mm and I get a build plate radius of 82.1773 mm. Using that for my X, Y, and Z points the extruder tip scratches on the glass even though it does not scratch on G1 Z0 F7000.

Any suggestions would be greatly appeciated.

Assuming you're running Marlin, this guide might be of some help:

[delta-calibration.s3-website-us-west-2.amazonaws.com]

Any delta will need to be calibrated as outlined above. Most of your values will probably be close, but small differences in build will throw things out. If your extruder is higher in the centre of the platform, then you need to increase delta radius.

I wouldn't concern myself with using autolevel until the printer is calibrated and prints. Regarding the hot end fan, do you have that hooked up to one of the D10/D9/D8 or whatever it's meant to be hooked up to? I have mine hooked up to one of these (can't remember which, and it's not correct anyway, I changed my pin config around after blowing up a MOSFET), and to start the fan you use M106. You can get Slic3r to run M106 on layer change to keep the hot end fan always on during prints.

Thanks for the reply.

1. Yes using Marlin
2. Fan is connected to D9. It works with the manual M106 and M107 commands, just will not go on automatically when I start a print or after hot end reached 50 deg C.

If your fan is used to cool the hotend, rather than the parts being printed, then it's a good idea to have it on permanently by wiring it direct to your 12V. Check out my Cherry Pi thread for a delta setup guide I wrote. If you follow the steps in there you won't go far wrong.

Did you write any start gcode in your slicer program ? Code something like this:

G21 ;metric values
G90 ;absolute positioning
M82 ;set extruder to absolute mode
M109 T0 S240 ;heat extruder and wait till it reaches 240ºc
M106 ;start with the fan on
G28 X0 Y0 ;move X/Y to min endstops
G28 Z0 ;move Z to min endstops
G1 Z15.0 F{travel_speed} ;move the effecetor down 15mm off bed
G1 X-15 Y-135 F11000 ;move to front of build platform
G92 E0 ;zero the extruded length
G1 Z0.2 F3000 ;move nozzle close to platform
G92 E0 ;zero the extruded length
G1 F500 E20 ;extrude 7mm of feed stock
G1 X15 Y-135 F5000 ;wipe nozzle
G1 Z0.0 P2000 ;wait for nozzle ooze
G92 E0 ;zero the extruded length again
G1 F{travel_speed}

Also this Delta calibration video is really good.

Edited 1 time(s). Last edit at 02/03/2015 04:39PM by d3delta3d.

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My delta build blogspot [d3delta3d.blogspot.com.au]

Custom Delta printer
300x500 build volume
magnetic effector
Smoothieboard controlled

thank you all so much. I am fairly calibrated and exerything appears to be working except for one major problem.... I can not get my PLA filament to actually print. I spent a few hours today trying everything I could. I set my temperature as high as 235c with no results. If I push very hard on the filament I might get a tear-drop out but then nothing but resistance. What am I doing wrong?

I have an E3D hotend and i can remove the tip and see right through so I dont think it is clogged. It may be the tip but unsure. Also not sure sorry for this stupid question but not sure when I load filament how much to push it into the hotend. ??? I did get out my caliper and the PLA I am using all aprears to be round and smaller than my 3.0 mm hotend. I also believe my nozzie is 0.4mm

Any suggestions would be so greatly appreciated.

THANKS

I had a similar problem all be it with ABS. First thing I would do is remove the nozzle and see if you can push filament by hand through a cold extruder. It should be free with little friction. This will rule out any restrictions in your setup.

Next, take the nozzle off and gently heat it with a small blow torch till the plastic is just melted. Then, holding a drill bit in your fingers (the bit diameter should be same diameter as the nozzle melt chamber) rotate the drill bit gently into the melt chamber to clear any plastic. What I found was a plug of plastic that did not want to melt. Since you can see through your nozzle perhaps you have plastic insulating the walls therefore stopping fresh PLA from the melting fully?

Once this was done I was able to heat the nozzle to extrusion temperature and push filament though it by hand very easily. Pushing 3mm filament though a 0.4mm nozzle will require more force that 1.75mm filament but is perfectly possible.

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My delta build blogspot [d3delta3d.blogspot.com.au]

Custom Delta printer
300x500 build volume
magnetic effector
Smoothieboard controlled

Two suggestions:

1. The fan must be wired to a permanent 12V output from the RAMPS, not to D9, so as to be on permanently. There are pins provided on the RAMPS for this purpose. If you try to extrude without the fan running to keep the hot end cool, the top end of the nozzle assembly will get blocked by melted plastic. This is probably why you can't extrude. You can connect a separate print cooling fan to D9 if you want.

2. Are you sure you are using the right thermistor tables, so that the hot end is at the temperature you think it is?

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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].