Saturday, November 21, 2015
I have used blue 3M painters tape on my Prusa Mendel i2 since I started 3D-printing in 2012. I could use the tape it for more than one print. Removing some prints would damage the tape, and then I had to replace some of it. The cons: the underside is not complete flat, and big objects still had warping on the edges. Note that my 3D-printer does not have a heated printer bed. On the edges the tape would stick to the object, but is tape is lifted from the bed. With the 3D lac the underside is completely flat and the warping is gone. And the printer still does not have a heated bed. An advantage of the headed bed would be easier object removal: after the bed and the object cools down, it comes of easily.
Sunday, September 13, 2015
Short running and small 3D-prints have never caused any problems on my Prusa Mendel i2 RepRap 3D-printer. On the other hand, bigger, hours long running 3D-prints often fail. Figure 1 shows the profile of a model that failed initially. The object is 10 cm wide and 3.5 cm high. Figure 2 shows the failed print.
As you can see, the top of the object is not closed. You can see that the printer had trouble extruding the filament. In the end, extrusion totally stopped because the hobbed bolt had eaten into the filament. My first thought was that a dirt particle had obstructed the nozzle. As the print is not finished, you can see the honeycomb infill inside the object.
Figure 3 shows the filament used for this print. The hole is the point at which the hobbed bolt had eaten into the filament. If you look close, you can see marks of its teeth on the left side of the hole. To clean the extruder, I heated it and then tried to push some filament through the nozzle. That worked without any problem! I did not expect that to work, if there was no dirt in the nozzle, what could have caused the hobbed bolt to eat into the filament?
When I looking closer at the failed print at figure 2, I noticed that the print did not stop at once, but that it had trouble extruding for some time. That led me to the idea to tighten the bolts that push the filament against the hobbed bolt. See figure 4.
|Figure 1: profile of the printed object. It is about 10 cm wide and 3.5 cm high|
|Figure 2: failed 3D-print|
|Figure 3: filament of failed 3D-print|
|Figure 4: tightening these bolts on the extruder fixed my problem|
|Figure 5: successful 3D-print after tightening the screws on the extruder|
Tightening the bolts that push the filament against the hobbed bolt solved the problem my printer had for a long time.
Saturday, March 21, 2015
|Our Barbas Sirocco 350 gas fireplace|
- there is no inspection hatch. You have to take it apart completely; which is not easy and a lot of work.
- do not forget to switch off the gas and mains power!
What I did found online, was the website of the manufacturer. I contacted them by e-mail and phone, they are very friendly and supportive. I called them and they sent me the documentation and told me the problem could be one of the three values or the modubox. The modubox contains the control print. To test which value causes the problem, I was told to swap the outer valves. If the problem does not change, than the cause is probably in the modubox. I took photo's while I was taking the fireplace apart, I could refer to those photo's when I had to put it together again. I recommend you to do the same!
|Front frame and glass removed|
|Red circle shows the panel that gives access to the gas connection|
Remove the fake wood and all the screws. Take out all metal parts. The panel in the image above gives access to the gas connection.
|Use a wrench to disconnect the gas connection|
After removing the panel, use a wrench to disconnect the gas pipe. Make sure the gas is closed!
|The unit removed|
When the gas pipe is disconnected from the unit, you can lift it and disconnect the electricity. Make sure the mains power is turned off! Note that the unit has sharp screws pointing down. You don't want those on your wooden floor or table.
|The unit with the modubox and the valves|
|The modubox enclosure and print|
After coming this far I decided to take the fireplace apart again and inspect the modubox. The image above shows the modubox enclosure and print.
|This stain took my attention|
The stain under the electrolytic capacitor on the print on the left, above took my attention. I used my multimeter to measure the capacity of this electrolytic capacitor. It turned out that it had lost all of its capacity.
Sunday, March 1, 2015
I created a Cruise Control build server status light for the Scrum team I am in. This project contains many things I love:
As you can see, the light is clearly visible for everybody. In Scrum this is called an 'information radiator'. I published the code and plans (check the wiki) on github:
- Writing a Windows application to control an Arduino over USB
- Writing Arduino code to act as remote control
- Designing and soldering a shield for the Arduino Nano to send the IR signal
- Designing and printing a 3D-printed enclosure for the project
|Clearly visible status light for our Cruise Control build server|
Sunday, February 1, 2015
I was installing a new computer that I also use to control my 3D-printer. Besides installing the software to control my 3D-printer, I remembered one special Windows setting I had to take care of: disable automatic reboot after windows update. I leaned this setting the hard way. One evening I started a long running 3D-print. The next morning I found out that my 3D-printer stopped halfway because the computer had rebooted.