Delta

It is assumed that you are using Marlin-AC and that you have the printer connected to a computer.

Just upgraded firmware to Marlin AC Gforce-9 and following calibration steps. G33 P1 completes fine. G33 P2 stops at the second point with "Error: Probing Failed" Any idea what the issue could be?

Check the Delta Radius parameter.

I just flashed my firmware with the new version, but it doesn't seem to work? // I modified the firmware and flashed my printer with the modified version, but the changes don't seem to have any effect?

Did you send M502 followed by M500?

How tight should the belt be? How do I measure belt tightness?

Question answered by: Experienced group members

Word of advice: be cautious with the "belt tensioning screw" at the top of the tower. It works by pushing the corner piece away from the upright and it's far too easy to over tighten the belts. This can lead to bent pulleys and worst case; bent stepper axle.

Answer: Tension the belt so much that you are barely able to split the two belts apart one carriage width distance, using your thumb and your index finger.
When you set the tension of the belt on one tower, use this as a measuring stick to set the others. Simply "flick" the right part of the belt (looking at the carriage), like you would with a guitar string. Listen and try to get them all play the same note. If you are def, then use two-finger-method on all towers.

Note: The most important part about adjusting the belts is that they are all the same tension (or as close as possible). And don't over-tension the belt or things will bend.

That's it!

Where do I put the four small heat sinks?

Put them on the small IC's on the stepper drivers. The stepper drivers are the small circuits ontop of the main board.

How do I verify whether or not my bed is at 90 degrees to the towers?

Use a square.
Or a protractor.
If you use a square, put one edge leaning to a tower, the other on the bed. If both sides are flush to respective surface, your bed is 90 degree to that tower. Repeat the process for all towers.

If they are not flush, adjust the bed by adding or removing spacers under the bed.

Note: Using a spirit level is considered as bad practice, because it measures against gravity and not the towers.

How do I change the filament?

Assuming you have filament all the way into the nozzle:

1. Heat up the hot end past 170C.
2. In the printer software (Repetier Host for example), issue a retraction of 50 mm or more.
3. Keep issuing retractions until the filament has exited the extruder (the stepper).
4. Insert the new filament into the extruder, the bowden tube and press extrude (50 mm or more) until you are close to the hot end.
5. Keep issuing extrusions but now in smaller lengths, until you see some coming out of the nozzle.
6. Turn off the hot end.

My printed object dimensions are off! How to fix?

Written by: Maxim Riabichev

If you have assembled your printer properly, your dimensions should be within acceptable margin of error. They most likely won't be perfect, but probably within 0.3mm on a 60mm target length.

If they are off by a larger amount, the first thing you need to verify is that your steps/mm on the axes steppers is spot on. If you tell the effector to go down 100 mm, then all towers should go down 100.00 mm. This setting has the biggest impact on your print object height.

The second thing you have to verify is that the diagonal rods are the same length and correctly measured. For example, I had entered a diagonal rod length of 215.2 mm and my dimensions of the QuickDeltaCal object were 60.9 in A, 61.0 in B, and 60.9 in C (referring to the towers here). After adjusting the diagonal rod length (with command M665 L225) to 225 mm my dimensions changed to 59.4 in X, 59.7 in Y and 59.5 in Z. I finally dialed the lengths in to 222mm and dimensions were 60.0(1).

If your steppers and rods are 100% but dimensions are still off, go ahead and try the guide below. Be warned, however, that adjusting the rod length and trim could lead to angle errors, i.e. your straight lines might no longer be straight.

The information below is based on this source. The PDF is very informational and the excel sheet very helpful. Thanks to "PurpleSensation" for writing it up. Also thanks to Steve Hennerley for translating it all to understandable language ;)

First assumption: You have run G33 and have an acceptable standard deviation value of <0.6.
Second assumption: You have printed the small delta calibration item on which you measure something that is supposed to be 60mm.

1. This link will take you to an online spread sheet which has three pages/sheets at the moment. Go there and open the "Dimensions" page (look down for pages).
2. In Repetier (for example), send the command M503 to get your current settings.
3. Find this line:
4. The L-value is your current diagonal rod length. The R-value is your Delta Radius.
5. Insert values into the corresponding cell in the spread sheet (read the instructions there).
6. Put the output values into firmware:
   #define DELTA_DIAGONAL_ROD <Diagonal rod> (without <>)
   #define DELTA_RADIUS_TRIM_TOWER {Trim A, Trim B, Trim C}
7. Flash/upload the firmware.
8. Send M665 L<Diagonal Rod> (without<>), followed by M500. Whilst you'd normally run an M502 after flashing - in this case you are (or should be) flashing the same firmware - so no need to clear the EEPROM.

Print the object again. Your dimensions should be closer to expected.

Note: You might not be able to get to 100% correct dimensions, because of the physical limitations of the printer and the G33 calibration routine (which changes delta radius ever so slightly every calibration).

My printed object holes are under-sized. What gives?

This is a common problem with most slicers. Google this issue and you'll see a couple of explanations.

A simple "fix" is to over-dimension your holes by one nozzle-width's diameter. So if you need a 10 mm diameter hole and your nozzle diameter is 0.4 mm, in the 3D model simply offset the hole by +0.4mm (this makes the diameter 0.8mm larger), and you should now have a perfectly sized hole in your printed object.

Another fix is to use a drill.

My effector is not reaching the bed after G33 command was issued. And/or is making "wavy" movement patterns in the air.

First, in configuration.h there is a line that needs to be edited depending on your effector version:
#define Z_MIN_ENDSTOP_INVERTING true
true for new effector, false for the old.

Second, if the config is correct, then this is a Z-min endstop issue.
Send the command M119 to check status of your endstops.
The Z-min endstop should be OPEN if the nozzle is NOT touching the bed (if the Z-min switch isn't triggered). You can test the switch with your hand and send M119 to verify the different states.

My LCD-screen shows Err: MINTEMP

Answered by: Trex Izmereniyax
This error is due to one of the temperature sensors (thermistor) being randomly disconnected or broken. It can seem to work when in the beginning of a print, but as the temperature raises it can fail.

The actual thermistor is a little glass bead with 3-4 cm long legs, these are usually soldered, but sometimes just crimped to the wire. The glass bead can break, but that would be more instantly fatal, most likely the solder joint has failed but the shrink wrap sleeve is holding it together "most of the time".

The solution is then to either repair the thermistor (re-solder the cables) or replace it.

How does one know which thermistor is faulty?
Use your slicer to find the broken one. Or you can look at the temperature reading on the LCD and find the one not changing with the temperature.

Which thermistor should one buy to replace the faulty one? Almost any will do, but mostly they are sold either without the wire, or as a hot-end bundle, so just get yourself a couple of cheap clones (via Aliexpress for example). You just have to find the same one in the thermistor table in the firmware (configuration.h) and find the number next to the hot-end in configuration.h #define TEMP_SENSOR_0 5

Why 150 for the steppers? Why 100 for the axes?

Answered by: Steve Hennerley
The diameter of the hobbed gear is smaller than the diameter of the belt pulleys. The extruder stepper motor has to rotate 1.5 times more (ie more steps) to push the same amount of filament as the axes do for the belt.

A really good source for information about print quality

Troubleshooting

A good source of information about the kossel 3d printer

Build manual Kossel XL & Kossel Mini

I3

Nothing here yet..