Friday Work Session

On Friday I worked on my Guass Rifle model so that i could calibrate Midas and print it. I spent about 2 hours just trying to figure out how to get replicator G to work, which the problem was a python problem, and was one of those problems that makes you bang your head against the wall. It turns out that you cannot move where Python is installed otherwise replicator G cannot find the Python executable file. I had also just spent about an hour finishing my model, so after a good amount of time I was able to export an .stl file, put it into Replicator G, and was able to print! The relief! The print went well, no real problems other than that it seemed to being pushing the plastic around on one layer and the top layer was not as smooth as i would have wanted but for a first print it was pretty good. I am going to fiddle with the model and then try to print it again.

Today is about Calibration

I tried to do some prints today but our calibration is off. The prints I have done thus far are pretty hollow. So we went through David Durant's calibration tutorial. Here are the results from our test calibrations.

Text 1

Extrusion Width over thickness: 1.7

Feedrate (mm/s): 34.1

Test 2

Extrusion Width over thickness: 1.7

Feedrate (mm/s): 33

Test 2

Extrusion Width over thickness: 1.7

Feedrate (mm/s): 33.25

Carve: .4

We decided to stick with a feedrate of 33.25 because that gave us the best results on the test prints.

Here is an email correspondance between Nick from Metrix and myself.

Hi Nick,

My name is Nathan, one the researchers on this project. Some of the issues we are having are that some of the stepper motors are really hot.

This is normal for steppers. Even if they are slightly above "too hot to touch" they are still happy. They should not got hot enough to boil water though. The stepper drivers should not get this hot though, if they do, they will need heatsink on the driver chip or you need to turn the current down until you can fit them with heatsinks.

When the z-stage is travelling up it does something to make a lot of noise.

This could be the stage stalling out, it really depends on the noise. A Z axis crank is a good way to tell if the Z axis is stalling since its motion would not be fluid during a Z move if it was stalling

Another issue we are having that is probably related is that when printing the makerbot will re-adjust its zero settings and start printing at a different location.

This is a problem with all systems that are open loop, though there are things you can do to reduce the chances of this happening (Most errors occur when pausing/stopping a build or if your skienforge settings are incorrect)

We just filed down the side of the z-stage that is closest to the chips. It was catching on the bolt heads located on the inside.

If you have any insite into these issues that would be wonderful.

Thanks,

Nathan

We just got a noise complaint from our neighboring office mate. We learned the hard way that there is little sound privacy between our two officies.

On the path to solving problems

We are currently trying to figure out why our prints have been coming out skewed and misformed. We realized that our y-stage belt tension was changing because the bolt to hold the pulley in place had become loose. We are new taking apart the stage to get the bolt tightened; hopefully this will fix our problem.
Nathan also gets the grubby paws award today.

Metrix Thoughts

Metrix is one heck of a place to work on Midas. There is definitely a wealth of knowledge there and we might be spending a large amount of time there if our MakerBot keeps acting the way it is. Going into the building I was a little apprehensive that we wouldn't have been able to use the facilities because of the need for a membership. I was pleasantly surprised when we could use the building no problem and also get help from the people there! We had to pay if we wanted to use the tools and other machines there but wifi was free and their help was extremely helpful and also FREE! We might actually get a membership so we can use the tools like the laser cutter, rep rap 3d printer and other small tools. All in all Metrix is a great place to work, especially if you are not in the realm of working through a school. Normal people would definitely find Metrix extremely helpful.

Metrix!

Fun times at Metrix! We learned lots, helpful insight from some very well educated individuals. Apart from solving the overheating problem we got a few helpful tips.
On the way to Metrix I didn't really know what to expect. When we walked in we were greeted by one of the workers, and we set our MakerBot down on one of the work tables. Another patron arrived just as we did and he was interested in our machine. It was nice to see that he was interested in the MakerBot, most people that I have talked to so far have had no idea what a 3D printer is much less a MakerBot specifically. Once we were set up one of the workers came over and we introduced ourselves and began talking with him. He introduced himself as Matt and gave us a tour of Metrix. He was very helpful and easy going. The whole environment at Metrix was very inviting, it felt more like a hangout spot for people than a business. Matt gave us a few pointers but had to leave to go pick up his kid from school.
One of the frustrations that I had been running into was leveling our z-stage. Matt showed us a new way to level the z-stage that required much less work.
Feeling motivated Wednesday between classes I tried to print out a Porsche Carrera that I downloaded from thingiverse. After Midas had been printing for about 20 minutes the x dimension of the print shifted about one half centimeter so the model was no longer printing correctly. I had to abort the print and go to class without solving the problem. Today, I'll try and get the Carrera printed again using skienforge built into ReplicatorG instead. Wish us luck!