Wednesday, December 28, 2016

My first slicer

Robert came over and we printed one of his X3G files. An X3G file is a list of commands for the printer. Normally projects start as a 3D model which is stored as a STL file. This is a model file that describes the shape. Then a slicer is used to convert the model (STL) to commands (X3G). Robert helped me skip this step and print one of his X3Gs. Here is what we got:


Notice that the detail is very good and there aren't any regularities in the robot.

My next step was to try to start with a model and produce my own X3G file. This is done using software called a 'slicer'. This is because it takes the model and slices it into layers, then produces tool paths for the printer. Some slicers to a bunch of other stuff like adding supports to allow for overhang.

I looked into Cura 2.3.1 but it doesn't seem to support the X3G output format. So I'm going to try Slic3r which can apparently work. I made a config following those rules and downloaded a gcode to X3G converter. The first thing I noticed is that Slic3r doesn't have pre-set configuration for my printer. This made my first print start off the print plate. I tweaked the settings and got a better result, but it was meant to be a gear which could move, but it wouldn't move.
Bad print (upside down image too)
I'm certain I could tune it to make it work. But time is short, so I bought Simplify3D which Robert recommended. It made a great print first try:


Good Print (rotates like a bearing)
My next project is to get the machine calibrated so it can achieve the more delicate parts with better surface quality and tolerances.

Sunday, December 25, 2016

A Change Of Tack - 3D Printing

Update

It's been a few years. I moved, had more kids (3 now) and now I'm not working on OSE. Mostly due to lack of time and access to tools.

My family got a 3d printer for Christmas this year and I want a place to document my learnings and experiments. So I'm back here trying to build a little independence. I got a PowerSpec 3D Pro Printer with about 13 hours of use. It has an updated power supply, firmware and extruder fan addition. With the firmware update, this functions exactly as a FlashForge Creator Pro-- apparently the PowerSpec is a rebranding of FlashForge done by MicroCenter.

Introducing Robert

Robert is a friend of my who has a lot of experience on this setup and says the following. Here are some notes he gave me.

On: SD card usage for 3D printing


The preferred way to use the printer is to copy the .x3g files onto an SD card for use in the printer.  That file has all the toolpaths, temperature, etc for the part you want to print.  The people that write the firmware recommend that as the most reliable method where the printer can run completely stand alone.

Just make sure to use quality SD cards and when you write files to them that they are unmounted before removing.  That will ensure any writes that may be caches get properly written out to the SD card.  I've heard of people just popping them out and possibly ending up with a corrupt file on the SD card.

Since there isn't a way to tell what temp and extruders are used by just looking at the filenames I just started a convention that I add the extruder and material type at the beginning of my filename.  Something like RA_ for Right Extruder using ABS or RP_ for Right using PLA.  The printer doesn't card but if you are scrolling through files at least you'll know what to expect.  I would use DP_ for dual extrusion PLA.  You can tweak the extruder temp on the fly if you need to but the heated bed temp comes from that .x3g file and since I use around 40 for PLA or 100 for ABS it is good to note what material is expected in the filename.  Files names should be around 30 or less characters.


On: Tools

This is a really handy tool to help remove prints off the bed.

On: 3D printing groups and software

This is an excellent group on the FlashForge printers:

https://groups.google.com/forum/#!forum/flashforge

The FlashForge FlashPrint can be found here:

http://www.ishare3d.com/3dapp/public/FlashPrint-ii/

With a thread discussing it here:

https://groups.google.com/forum/#!topic/flashforge/eCWwWSLbRqY

One of the free programs that shipped with these printers is ReplicatorG.  The latest version is available from:

http://www.thingiverse.com/thing:32084

The sailfish manual also has some great tips on 3D printing.

I only use it now for Firmware updates but it does work once you know how to work around it's quirks.  One of those it manually editing the Gcode to set the bed temp for PLA, saving it, and then writing out the maching (.x3g) code.  If you don't save the gcode after making an edit then it doesn't make a difference since the portion generating the .x3g uses the file from disk.  If you forget to save then it ignores your changes...  It is also a slow compared to the other tools.

The tool I use now to prepare the models to print is Simplify 3D.  It runs $150 but has been worth every penny.  It can be installed on up to two systems concurrently.

https://www.simplify3d.com/

They have a troubleshooting guide that is excellent:

https://www.simplify3d.com/support/print-quality-troubleshooting/

Some other 3D printing groups:

https://www.facebook.com/groups/flashforge/?ref=bookmarks

https://www.facebook.com/groups/3DPrintProps/?ref=bookmarks

On: Creating 3D models

Here are a few sites where you can create 3D models.  All free:

https://www.tinkercad.com/

http://www.123dapp.com/ - apparently closing down early 2017


http://meshmixer.com/

https://www.blender.org/

On: Sample 3D parts

I can bring over some .x3g parts that i've already printed.  We can start first just printing existing parts to ensure the bed is leveled and adjusted.  Once that is done next step is to pull down some existing models from:

http://www.thingiverse.com/
(my account)

or

https://www.myminifactory.com/

so you can get familiar with the prepping of the parts and printing them.  After that the sky is the limit and you should be able to model up and print anything you want.


Thursday, June 13, 2013

How much power is there in PowerCube?

How much power does a PowerCube produce? There are several versions of PowerCube, with various engines. For example, my unfinished PowerCube IV will have a Briggs and Stratton 37 horse engine. When I'm done I have no idea how much power it will generate. I don't know what sorts of load it will be able to move, or how fast it will be able to move them.

Videos of LifeTrac are impressive, but I'm an engineer. What will it be able to do? How will I know if my PowerCube is subpar or by some fluke perfect? I belive that PowerCube VI is under development, but can't tell you if the new designs are more powerful than the old ones. (I also can't speak to reliability but that's another story.) If OSE is going to rapidly iterate on its designs then it needs to know when an iteration is better.

I understand that Tom is putting a bigger engine into version VI. How much better will it be? What is success?

OSE needs a simple fixture to measure hydraulic power output under various conditions. I'd suggest the initial design allow the independant control of at least two variables: load, and fluid capacity. I'm not sure what it would need to measure, but suspect that measuring pressure drop over the load could stand in for power manifested. A more complete design would also measure absolute pressures, and flow rate.

Here is a possible implementation. A non-load bearing cylinder (the kind that stores fluid when expanding) in parallel with a needle valve. A pressure valve before and after the needle valve. Expanding the cylinder would decrease the level of the hydraulic tank. Tightening the needle valve would simulate a load.

As a complete novice in hydraulic design, I'm sure the above is wrong. However the concept holds. We can measure any PowerCube with such a fixture and can definitively show progress (or its absence). Finally, such a fixture may be very useful in diagnosing failure modes in the PowerCube (such as stalling.)

I'd love to see some data on what the earlier PowerCubes can do and how they measure up to the new ones!

Thursday, February 21, 2013

Perhaps the glut of STEM workers is fueling the open source economy?

America has too many Science, Technology, Engineering, and Math experts. There aren't enough jobs for our high tech graduates. You may not think so, but the story is coming out. Perhaps having a lot of highly trained, unemployed people isn't all bad though. There are a number of great movements that rely on voluntary donation of technical work. Opensource Ecology is only one of many.

These projects wouldn't be going anywhere if they didn't have people with the time and energy to work on them. I suspect that a lot of the work is coming from STEM workers who are under employed. This would be somewhat ironic. The story that there aren't enough STEM workers appears to be intentionally woven by large employers in order to depress labor costs. If that's so, then what a surprise to find competing products on the market made by the workforce they've tricked.

Monday, July 16, 2012

Some possibly contentious thoughts on copyright law.

After reading a Forbes article about Megaupload and copyright law, I had some thoughts that have to do with copyright. I think they are relevant to the 'open hardware/software' movement. Keep in mind that these thoughts are mine alone and are not the statements of Open Source Ecology.

To me there are two kinds of things that can be created. The first is kind of thing can be reproduced for approximately zero cost (like music and text). The second type requires human or material cost of meaningful quantity to reproduce (like clothes and books). These two types I'll call Type Zero and Type One respectively. I can't think of anything that have used to be Type Zero and is now Type One. Can you think of anything? However, many things were Type One and are now Type Zero-- thanks Technology! The written word, engineering drawings, images, music and video are all examples.

Many businesses are based on using Type Zero things (such as engineering designs) to produce Type One things (such as cars). Copyright protects Type Zero things-- it makes something that is free to reproduce have a cost. Such protections have been historically needed in order to encourage invention.

Copyright has gone out of control in many ways. Plenty of people live without producing anything of Type One. These people depend on income associated with something they made of Type Zero. Think of a musician who is living off of royalties. It seems unnatural that a person can have one idea which guarantees their material wealth indefinitely.

Our economy has a lot of features which funnel money from the people that create Type One information (think factory workers and cooks) to those that create Type Zero information (think CEOs and Programmers). I find this ironic as Type Zero information is freely copy-able. Shouldn't it be in extreme supply?

Instead, Type Zero information is heavily protected, horded, and traded. The makers of Type Zero information are highly prized and rewarded while those that do Type One work are frequently devalued and left out in the cold.

An Open Economy can help to reduce this imbalance. By giving away Type Zero at all levels, competitive waste is reduced. Type One workers will have access to the designs for better tools and processes. They will be more productive as a result. The resulting market will produce only as much Type Zero information as needed instead of hundreds of variants all intended to circumvent rules about copying. Workers will be able to produce more Type One product for less effort. Prices will fall and work days will shorten.


We already know that a large segment of the population like to do Type Zero work. These are the Open Source programmers, hobbyist musicians, and filmmakers, and makers of all sorts. These people are working towards a world where they can produce less Type One product, live well, and truly explore their Type Zero aspirations. I am one of them and I hope we succeed.


[I'm not certain of my conclusions, or of the future. However, I'm excited to see the results of the transformation that is currently underway.]

Thursday, July 5, 2012

What is OSE doing in New York City?

What a whirlwind trip. This Friday I drove to NYC with my awesome family and stayed with Andrew and Chrissy (who also rock!). I helped represent OSE at For Humankind. It was awesome! I got to meet Aaron who will be living at Factor e Farm soon.

The event was a sort of exposition of human centered technologies. There were people turning soccer balls into little self charging batteries, others could turn any surface into a touch screen, yet others were working on turning algae into a high production bio fuel.

And of course, there was OSE. And my PowerCube! I got to show it off to others and explain the challenges of building it. I got to explain how the work of OSE made them inherently more valuable because it allows them to start a business that was previously out of their reach. I got to learn about their interest and goals. It was incredible how many intelligent, curious and engaged people came by to see what we were about.

I'm also happy to report that this kicked off some collaboration between Graham and myself. Graham will be building MicroTrac at FeF and we've been discussing goals and some design aspects. I'm excited to see what we come up with.

I've been invited to FeF, but given my current circumstances, I'm doubtful it would be practical (despite my real desire to make it happen). So for now, I'll work on getting my life in Detroit up and running. Then I'll finish my PowerCube and see what is next.

Thursday, June 21, 2012

Meeting OSE in person in New York City?

I've recently been in touch with Aaron of OSE. He has invited me to visit NYC to show off progress on my PowerCube 4. I'm hoping to make it work. I've got a query out to some friends-- I'm hoping they can host me.

Here is the most recent photos of the Power Cube with captions.

Top View of Power Cube

Notice the minimal clearance between the tank and the engine here.

Gas Line connecting tank to Engine.

Gas Tank was a gift. Cheap, but effective. I will mount it more permanently when time permits.

Fitting for Engine Electrical



The Engine in profile