3D printer maintenance and repair

Hi there, today I will talk about what I have learnt from helping to fix the class printer which had become clogged from its nozzle to inside the extruder head. We began by removing the printer block which contains the extruder, the heating element, a fan and the nozzle.

The printer block is connected to the machine by a magnet and there is a ribbon that plugs into it which unclips easily. To access the extruder cog there is a number of small bolts which are removed using an allen key. Removing the nozzle from the block requires a small socket wrench which comes with the machine.

After trying to remove the nozzle and unclog it, we realised that it is much easier to do so when the block has been brought up to printing temperature which is 260 degrees Celsius. Once up to temperature we unscrewed the nozzle and ran a special piece of wire that has a rough surface inside it to clean it out. We also used a drill bit to clean out the extruder which worked quite well because turning the bit inside the head caught all the softened plastic and bought it out in one go.

How it became clogged in the first place is unknown, it may be the type of plastic or it may have been a breakage with the cord causing it to harden inside the block. What we have learnt from this is to stop trying to extrude it once there is a problem because it can cause the cord to start to clog the whole block once the nozzle has become blocked.

Gears and constraints

Hello there, I have been looking into gears and how they relate to one another. After a few goes I have created a working set of three different size cogs. I then did a tutorial on rotation and transformation constraints that I found on youtube. Here is the link.

http://www.youtube.com/watch?v=j1WNbpX7HPo

What I learnt about making these cogs rotating together is that it's pretty simple to link a larger gear to a smaller one by using a rotation constraint and dialling back the influence of the smaller cog. This is where the number of teeth is important, to make gears run smoothly together they need to be in uniform ratios, I used a 50% ratio.

To make a smaller gear run off a larger one, you need to use a transformation constraint because the rotation constraint doesn't allow a rotation influence of more than one. The transformation constraint can also be used for location and scale restriction but also rotation. This way you tell the object how much it will rotate during a certain rotation of the target object. This rotation was 360 degrees was for the targets. Making an object rotate on a different plane involved using another feature of the transformation constraint which could tell the constrained object what rotation axis it would use for it's selected rotation. For example telling a cog on the x axis to use the z axis rotation of the target object as is desired rotation.

I had a little trouble with this feature in that it seemingly would only work for me one way and caused me to change my main cog to a y axis cog rather than the original z axis rotating cog. Here is how it turned out, I'm happy with how the gears mesh together, hopefully they will work in real life when I print them out.

Gears - Learning to build

Hello there, I did a quick tutorial on how to model gears in blender. It was pretty easy, the next step is learning to give them relational functionality. I found a good tutorial on how to add constraints and make the rotate together as well as defining ratios. That will be the next step. Here is the link for the gear build tutorial.

http://glupor.blogspot.com.au/2012/06/blender-tutorial-1-making-cogs.html

Here is an image of the cogs I built.

Here is a little video of the walk cycle I did as a tutorial. This was quite straight forward to learn, it dealt with manipulating a rig into four different positions and inserting a keyframe for each one in the timeline. By pressing the I key the position of the selected parts become a key frame and will always move to that position at that time. It is a good idea to have everything selected on your model when making a keyframe for an organic object because other parts may move slightly as well.

The other part of the tutorial was making the model walk along a path rather than walking in place. by going into the NLA editor I was able to combine both the motions of walking and moving on a path to make the model walk along. This makes life easier, by being able to loop the walk cycle and just move it around it saves alot of time that would be spent making keyframes. The graph editor was able to change the velocity of movement to a constant rate by making it a vector line after pressing the key V.