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The Reprap is an open source design for a home-made 3D printer. This project will be dedicated to create a replication (2nd generation) Reprap. It will includes: lots of soldering, construction, experimenting with various printing materials, making test prints. This project will take place at the Science Center.

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Reprap 3D Printer (minor AP 2010)

Documentation (in Dutch)

Detail photo’s

Now the project is finished we made some detail photo’s of some parts and a documentation. The documentation will be uploaded later, for now just some photo’s:

Science Fair

Yesterdaymorning, just before the Science Fair started in the Science Center, we were able to control all three axes manually. We thought the opto senors were damaged because earlier we could only move some axes in one direction and the home function didn’t work at all. We decided to replace the optic sensors with switches. After messing around with the wires we finally got all axes to work properly. There was no time to fix the extruder so we prepared for the Science Fair in which we showed both Repraps (non printing), a poster of how the second reprap will be used in the Science Center, all parts we were able to print with the first reprap, some movies we made during printing with the old reprap and we demonstrated the moving axes of the second reprap. 

Unfortunately we were not able to complete the second generation reprap in time. The main cause of this was the three weeks delay of the ordered reprap package. We’ll probably need another week to get the second reprap to print it’s first parts. However, now the project is finished we need to consider the things we still want to finish and things we leave the way it is. We will make a documentation of what needs to be done and how some problems with printing can be solved. Also some close up photo’s will be made to show how things exactly are put together.

Sensors and wiring

Today we assembled the optic sensors and did something with the electronic wiring. As can be seen in the picture below some creativity is required to place the sensors and make sure some material (like a copper wire, piece of wood or screw) will run through the sensors (see picture). We’re not sure if it all works but it looks fine. The sensors are used to set the extruders home position.

We also connected the stepper drivers with wires to the electronic boards so that now ledlights will glow up when moving the axes.

More assemble

Today we made good progress. We now have all three axes fixed together, a bit of the extruder and looked at some electronics.

Assemble

Today we worked hard on assembling the new printer.

 

PLA

When the PLA filament arrived we were pretty exited and exchanged the ABS filament for the PLA right away. This was a hard job since some ABS was molten in the extruder nozzle. The rest of the filament we were able to pull out, but the molten pieces we had to push out with the PLA while heating the extruder. This gave a problem since the ABS will melt at temperatures of about 245 °C (according to our temperature sensor) and the PLA at about 190 °C. We heated the extruder up to about 250  °C, let the extruder extrude and pushed the PLA through the nozzle. We got rit of most of the ABS filament but due to high temperatures the PLA was now molten to the extruder’s nozzle. We couldn’t get rit of this in first place so we disassembled the whole extruder as seen in the picture below. In the white tube below you can see some white ABS at the one end, the rest of it is fulled with the blue transparent PLA. We cleaned this tube using a hot soldering iron with a sharp pointed end.
Now it was printing time and according to Reprap traditions we first printed a small beer glass. Here the result:
A great result, but the challenge was to build big parts which don’t bend during printing. As can be seen in the picture below the PLA succeeded. The part is perfectly flat at both sides, however, the part is not finished. While printing the filament again melted to the extruder’s nozzle. Like people say on internet, PLA doesn’t bend but it gives a lot of problems. After removing the filament in the nozzle we replaced the wooden round part (with 7 holes and some cables running through, see picture on top) with a self sawed and drilled part. We did this because the radius of the original part was to big (about 4mm). Since the PLA has a smaller radius than the ABS we used, we changed the radius to 3mm (same as PLA) so no PLA could stick to the sides of the part while extruding it (since it will get pushed further with the PLA behind it). With hope we turned on the printer and tried printing some parts, but unfortunately the same problem occured again.   
We haven’t found a solution yet for this problem and we were really in a bad mood now the PLA doesn’t work either. And than, all of a sudden, the ordered package with all parts for the new Mendel printer arrived. Although we believed this packege would not include any reprapped parts we had to print ourselves, we did notice some of those parts in the package. It would really be ridiculous if we now found out all parts we printed are useless. We’re not sure yet if we have all parts, because most of our printed parts are different than the ordered printed parts. Anyway, we started building the Mendel printer and try to use as much of our printed parts as possible. We’re glad the package finally arrived and we can now still aim for the deadline over a few weeks.

 Below a picture of the parts we think we can use for our printer. Some seem perfect, some are bent a bit but that shouldn’t be a problem.
The usefull parts so far

Timelaps video

Tray of parts

We tried printing a tray of small parts again. In the movie you see some seconds of the first attempt. It failed because the speed rate was way to fast which made the extruder end hit one of the parts. A photo of the result is already posted in the ‘Raft’ post.
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