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Monday, February 20, 2012

First prints

After redesigning the carriage and building a new hotend I was off and printing. As usual I started with Teacup and every print finished but the machine was noisy at the speeds I want to print at. The results were not exactly what I wanted either, but none the less still good.
The first three cubes are printed with the old hotend and Teacup. The next two and Yoda were printed with the new hotend and Teacup. I then decide to make the switch to Marlin which resulted in excellent quality prints and the machine sounded much better. But as you can see I could not complete a single build because of the communication errors. I posted a thread on the RepRap forum about it but no one has responded yet. While waiting to find a solution to the serial error I decided to try hooking up my DIY sd card reader (card slot and schematic) which went terribly wrong. The first symptom appeared when the temp would read 266 so I swapped the hotend and bed thermistors in the firmware and was getting good readings again. But the Y axis and Z axis only moved at about 10% of the speed requested and only move half the distance. I have removed the SDreader and checked all the connection points and there are no shorts or loose connections so it looks like my arduino mega is done. This is going to set the project back until I can sell another set of Prusa parts to raise the money to continue.

Here's a video of the fourth print it ever did. First with the new hotend.

Hopefully it won't be to long before I can continue development.

6 comments:

  1. I noticed one of the smooth rods on your machine rotates. That might be ok while you are using plastic sliding bearings, but might not work well with LM8UU ball bearings: they are designed to provide smooth linear motion (when the balls travel along their pass), but not free rotation relative to the rod.

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    1. You may be correct and that may be why Ultimaker uses bronze bushings. But I have spent the morning reading http://www.skf.com/medialibrary/asset/0901d196800cf943 data sheet from SKF and only found one mention of rotation causing damage to the bearing and it was for a zero clearance bearing. If a find they wear far to fast we always have the option of printed bushings, bronze bushings or Igus bushings.

      P.s. All the outer rods turn that is what drives the wires/belts. For more info on how it works have a look at an Ultimaker.

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  2. do you have an ETA on when or if you will publish the designs of this? I am printing tons of Tslot so i can use that for the frame.

    i think going with the bronze bushings would be totally sufficient for this printer. keeps the costs lower and they basically don't wear out.

    looks very cool, cant wait to make something similar. I plan on driving it with an old set of makerbot electronics.

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    1. It will be a while before I release them at the moment. As I said I have had some set backs.

      I don't think you will have any luck using the t-slot as a frame. It would end up using more material being made that way. This design uses large flat thin pieces to give stiffness while using as little material as possible. As well as having all the mounting points designed into the frame. If you would like to build a machine like this out of t-slot I would suggest having a look at TwoTimes Mini-Maker on Thingiverse. It's designed to use T-slot as a frame.

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  3. You should release the files so people can help you improve the design.

    Better yet start a git hub like prusa so it is easy to collaborate

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  4. This is DAMN cool. Very good results, congratulations! I think it's one huge step closer to a fully-printable Reprap. I can't wait to print one of these babies.

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