Evolution of a Blog

This blog has evolved as you can tell by comparing the title with most of my recent posts. The title should really be something like "The Physical Interface Side of Computing". It will still feature Raspberry Pi and Arduino from time to time but my current hardware of choice is a BeagleBone Black with JavaScript and Node.js providing the development environment.

Saturday, May 2, 2015

Pretty Happy With Most Print Quality

I am not sure that I can get much better than this!   These were printed in ABS with a layer height of 0.1mm at 30mm/sec.

Still working on the issue with some angles but pretty happy with this kind of result.

BTW, those are 5mm cubes making up the stack on the left.  They are measuring in at 4.97mm x 5.02mm x 4.96mm.  I think that qualifies as reasonably good for dimensional accuracy as well.

Some more calibration objects, including my ongoing problems, are shown in the second image.  The surface finish test, left most is pretty good and the Marvin is great but for the ridge above his left eye.  The big problem are the edges of the pyramid.  I am assuming this is ooze but have not been able to get rid of it with the various ooze settings.

Finally, a couple more calibration objects.  Obviously the very extreme angle has an issue but I would never design an angle like that anyway.

Friday, May 1, 2015

Down to Brass Tacks...

...on getting the Duplicator 4S dialed in. This is pretty high level of detail work.  The layer height is 0.1mm and as you can see from the coin the objects are pretty small.  It is just certain angled shapes that seem to cause the printer some issues.  The columns are all nice as is the very base of the pyramid.   Even the loop at the top is good.  Just one corner of each of the columns going up at an angle has a rough edge!

On a larger (2x) version the effect is less but the back of the leg is much rougher than the front.

Tuesday, April 28, 2015

Printer Suddenly Acting Up - Conclusion

Printer was simply trying to go too fast!   Someone on the RepRap Forum suggesting I try a slow down and it worked.  I was trying to print at 60mm/sec.   With the same printer he indicated that he prints at 20-30 for customer work and 40 for his own.   In fairness Wanhao Support had said to slow it down to 50 but I was running at the default for the printer from Simplify3D and was being stubborn!   In a post or two I will show some results.

Thursday, April 23, 2015

Printer Suddenly Acting Up - Part III

Ok, nothing had completely solved my issue entirely though each thing that I did seemed to help a little.   The latest changes that I have made were to replace the hot end and PTFE on one of my extruder's, and more importantly, to replace the spacers on the clips that hold down the FR-4 on my build platform.
Here is a photo of the hot end and PTFE tubing that I replaced.   To me it does not look like it is in bad shape.   Additionally, I only replaced one side and the other is performing the same as the side that was replaced.

That leaves a tighter build platform as the culprit.  Which I can believe.  Here are two photos of a print before and after the build platform fix.

As you can see on the right most of the whiskers are gone.  Interestingly, though, not all.

What confuses me is why it is always the same place on the print that we see this issue.   Doesn't that imply a slicing issue?

Tuesday, April 21, 2015

Printer Suddenly Acting Up - Part II

I am not sure this is resolved...but...my first thought was that something might have worked loose.  I checked everything, or so I thought, and did not find anything that was noticably loose.  I did tighten the bolts that hold the sides of the case but these are not structural.  They were, however, very loose and it did seem to help a little?  Could just have been me.

In any case my post on the Reprap Forum confirmed my original suspicion that it is probably something loose so I checked again.   This time I remembered to check the two bolts that hold on the extruder assembly and sure enough they were a little loose.  I do mean a little but every little can count.   So I tightened them.

In order to check these bolts I had to take off the directed cooling duct that I have installed.  This duct not only blocks those bolts but it makes it challenging to see the nozzles.   Once it was off I was able to notice that the nozzle that I have been using was in bad shape with caked on plastic.  So I cleaned it.

I have done a couple small test prints and I think it might be ok now.   In a few minutes I will do the real thing.


I have started to do some instructables.   In some cases using content already posted here and in other cases a new topic.   Here are links to the three that I currently have published:

This instructable describes the building of a case for a Raspberry Pi that incorporates a pan-tilt assembly for the Pi Camera.  posted on Apr 19, 2015
This instructable presents a way of securing glass or FR-4 without using a binder clip there-by preserving as much build space as possible...and...avoiding having a nozzle drag across a binder clip!  posted on Apr 18, 2015
This instructable illustrates how Sketchup can be used to create dual extruder (e.g. two color) 3D prints using Simplify3D as the slicer.  posted on Apr 8, 2015
As you can see one of them has been "featured" for what that is worth!