Evolution of a Blog

This blog has evolved as I have as a maker. It starts at the beginning of my journey where I began to re-tread my tires in the useful lore of micro electronics and the open-source software that can drive them. While building solutions around micro-electronics are still an occasional topic my more recent focus has been on the 3D Printing side of making.

Tuesday, September 25, 2018

Building a Weather Station - Part 1

I have wanted to build a weather station for a while but have never had a location to put one. I still don't, in fact where we are now is the worst possible location due to the surroundings, but I'm hoping that I can build one for one of the local boating places.  Actually I hope I can find a home for the one I've already built!

 Here is a diagram of what I have built.
  1. Instruments include (wind speed, wind direction), (rainfall), (temperature, humidity), and (barometric pressure).  Wiring = (4 wire RJ11), (2 wire RJ11), (Grove Cable), (Onboard)
  2. Instruments are connected to a board from SwitchDoc called the Weather Plus that has a microprocessor with a Wifi adapter (programmed using the Arduino IDE).
  3. Weather data is available either via an Http interface or via a stream from the onboard serial port.  I elected to integrate with both to test reliability.
  4. A Raspberry Pi Zero is used to interrogate the Weather Plus board to feed an instance of Weewx, a popular open source weather station package.
  5. A webcam could also be supported in a follow-on phase.
  6. Weewx integrates, out of the box, with both the Weather Underground and with Windguru.
  7. Additional resiliency might be provided, in a follow-on phase, by adding a monitor capable of power cycling the entire platform (Arduino with a relay)
 The most challenging aspect of the configuration is building for resiliency. This is what I am testing now:
  • Single Http (Read) Error
    • Wait one minute, try again
    • Cleared on next good read
  • Five Http Errors
    • Reset WeatherBoard
    • Sleep for five
    • Cleared in ten minutes
  • Five more Http Errors
    • Reboot
  • Five more Http Errors (Phase 2)
    • Power cycle WeatherBoard
    • Sleep for five
  • Handled by a "Monitor"
  • Watch time stamp of “lastActive” file created by toWeewx on every update created
    • If it does not change in 15 minutes reboot (5 for the serial interface)
    • Cant use the feeder file between toWeewx and Weewx as it is touched by both sides

Wednesday, August 8, 2018

One Project - Three Interest Areas

Many of my projects combine two of my interests, 3D Printing and Micro  Electronics but this one combines three! in this case the extra one is barbecuing in that I have gotten a new ceramic grill, a  Kamado Joe, and am building a heat control unit for it.

The 3D printed elements of it are the enclosure for a fan and a shutter that will be used to direct air into the grill and a case for the electronics that drive the airflow.    The electronics will consist of an Arduino on a custom designed circuit board that is a daughter board to a Raspberry Pi Zero.   the Arduino will run firmware that will slowly restrict airflow as a temperature is reached while the raspberry will provide the graphical user interface wirelessly on the home network.

Monday, April 9, 2018

N-Scale Drawbridge - Project in Progress

This is a project in process that needs a home.  I started thinking I would do a diorama but have neither the time nor the space.



It is loosely based on this prototype but I've taken creative liberties to make it easier to print as a 3D model. 
 not printed the second tower but obviously I would if somebody purchased the model.   I would provide the second tower is parts that would need to be assembled.

 The bridge is two tracks wide  but height is closer to scale then would  be necessary to accommodate some of the tallest rolling stock.


  My vision was that the counterweight will rise and fall with the bridge




 here you can see the attached points for cables. 


 My biggest regret is spending so much time on rivets and not making the line straight! 
 Girders are not through 
holed for Ease of printing purposes



Counter weight would rise and fall as did the prototype.


Top showing what I was thinking for lifting

Close up of what I intended for lifting
I would like to see this bridge in a layout and will give it to anyone that is actively working on a layout and that will commit to using it (and will post pictures).  In the ideal case I would like to see a donation to the MS Society for whatever amount a recipient of the bridge feels is worth while.

Wednesday, April 4, 2018

Using the NanoDLP Mask Generation Wizard

There doesn't seem to be a good document out there on how to use the NanoDLP mask generation wizard someone going to do a quick one that at least provides an overview.

The first thing you need is a meter that can read the UV light coming from the printer. There are number of options discussed elsewhere on this blog.  You can whip one up using a voltmeter, (with a battery, a resistor, and a photoresistor),  you could use one based on an Arduino microprocessor (with a resistor and a photoresistor), or you could use a commercial device.   As the readings are relative to each other it doesn't really matter what you use!

You also need to understand the screen orientation as represented by NanoDLP  relative to the actual printer.   This article should help.

 Of course you should also understand conceptually what you are trying to do! A mask is a grayscale image that evens out exposure from the less bright areas to the bright center. The mask will be clear at the edges where the light doesn't reach as well as the center where it will be dark. The wizard lets you measure points on the screen and adjust them so that they are all at the same level of brightness. It then generates a mask based on those readings.

As this is just an overview I'm not going to talk about the details of creating a mask as you should be able to figure that out by messing with the wizard. In general what you need to do is display the grid of cells  of the size that you will use. Find the one that is the dimmest, usually one of the corners.  Adjust all the other cells to the same reading as that dim cell. Generate the mask!

I believe the new is diversion of the wizard allows you to export a CSV file that represents the mask.  My D7  is currently in pieces being upgraded so I am not sure of this.  If indeed it does you should save one of these exports!   I would also recommend getting the image file that is generated by the wizard from the RPI and saving it on your workstation. You can then upload it at your leisure and use it only when it is needed as opposed to all the time with longer exposure that goes with it.


Monday, April 2, 2018

3D Printed Tiles for Terraforming Mars Game

This is an auction for a set of 3D Printed "enhancements" for the terraforming Mars game.    All proceeds from this auction will go to support my wife's run in the London Marathon on the MS Society team.   I am not using the eBay charities functionality so that the donation will be credited to the right place within the MS Society.

Link to the eBay Auction

The set consists of game tiles, the markers for Generation, Heat, and O2, a case for all of the afore mentioned bits and a direction coin for drafting.

The tiles are as follows:

  • 9 ocean tiles
  • 16 city tiles
  • 25 green space tiles
  • 11 special tiles

The special titles are as follows:

  • Borer area
  • Business district
  • Capital city
  • Industrial area
  • Lava flows
  • Natural Park
  • Nature reserve
  • Nuclear containment area
  • Rights area
  • Two mining areas


Complete Ready for Shipping
Complete Set
Close up of Greenery Tiles (Matt PLA)

Special Tiles

Closeup of City Tiles

Ocean Tiles

Direction Coin for Drafting as well as O2, Temperature, and Generation Markers (printed with CopperFill and then polished.

Note that this set of tiles is being sold with the full approval of the author given that the proceeds are going to the MS Society.

Link to the eBay Auction

Friday, March 2, 2018

My Powered Chair and 3D Printing

I don't think that there is a mention in this blog that identifies me as being disabled.   I am fighting MS and have progressed to needing a wheelchair to move around easily as muscle control and fatigue combine to make mobility a challenge.  Luckily I could afford one of the best powered chairs out there, the Quickie Jive Up, to meet my needs.  There is no doubt about it when I say that this is the Mercedes of powered chairs.  I say Mercedes as the manufacturer is Sunrise Medical and they are in Germany.  I say Mercedes and not BMW (my previous cars) as Sunrise Medical is near their headquarters and not in Bavaria.  If I could drive a Mercedes I would but since I can't at least I am lucky enough to be able to afford the Jive Up.

The chair is based on the Quickie Jive M which has a mid-wheel drive and an adjustable seat all controlled by a joystick and or some buttons.  The mid-wheel allows the chair to turn in its own length and the suspension that the chair sits on makes for a decent ride.  The seat is adjustable from sitting to laying flat.  To this the JIve Up adds the ability to stand with some useful positions in between.

Yes, it is a monster!  It looks even bigger than it actually is due to it being in a position call "transition" which helps me get out of it and into my office chair (or other chairs and seats).  It can continue to raise the seat until I am standing.  It is those extra servos and controls that make it so bloody expensive.  It is capable of 6mph and can run on streets legally.  A battery and motor upgrade allows for 8mph but at the expense of torque so I went with this one.

It has greatly improved my life already in that I can be much more useful to myself and Sara compared to being in a traditional wheelchair or on crutches.  I can actually carry coffee in one had while I drive with the other.  Believe me when I say that small things matter.  One of the positions the chair offers is between sitting and standing and is one that I use most frequently in the kitchen.  With it I can much more easily get things done that would otherwise be a struggle.

This does not even begin to touch on the ability that the chair will give me to get out and about this spring...combined with a new car to carry it.

This will not come as a surprise to anyone with a 3D Printer, or anyone that has read this blog for that matter, but within minutes of having it I was already thinking of how to modify and enhance it.  The first thing that I designed were two brackets that can hold my grabber for when I inevitably drop something.  This is a frequent occurrence as I have lost some coordination in my hands.

Soon after that it became clear that the arm holding the controller could be improved.  The one that came with the chair was very adjustable but came at the expense of a little added width.  So I designed one that was the right length and orientation for me, that included places for the two buttons that I had purchased for the chair, and was no wider than the chair.

Having done the controller arm I then did a mount for the other arm that I intend to be interchangeable.   You can see in the photo with the controller.  Right now the one inserted into the mount is for my iPhone.  As you can see in the picture there is a charging cable that leads back to the chairs battery compartment where I have installed a 24v-5v voltage converter that provides the 5v power to four USB ports.

The last two additions had nothing to do with printed plastic but add convenience.  First, a saddle bag that fits perfectly under the right armrest.  Second, a general purpose shoulder bag that fits perfectly across the back of the chair (not shown). Third, and finally, a retractable seat belt replacing the non-retractable version that came with the chair (also not shown).

Monday, February 19, 2018

Micro Studio - Photographing Tiny 3D Prints

The level of detail printed by my SLA technology is such that a macro lens is essential if you actually want to see the finest of those details.  I have been using a macro lens attached to my iPhone for this with pretty good results as described by a previous post.  I may have even gone a little further than I needed to set up a mini studio!

What the iPhone solution delivers in terms of convenience though is lost in quality.  Lack of depth of field makes focus across any distance problematic and the various forms of optical distortion caused by tiny lenses is not a help either.  Enter my SLR.  I have Canon SLR and a macro lens and macro flash that I had purchased a while back.  I have never really taken the time to set it up for easy capture of the small models that I print until now.

Here is the my setup:
Woeking Bits

  • 3D Printed stand for the camera and macro lens
  • The actual camera and macro lense
  • Rotating platform for the object to be photographed
  • Elevator to raise or lower the floor on which the subject will sit.
  • Backdrop holding paper that could be white or black
  • PC (or Mac in this case) running Canon's EOS Utility
    Close-up of the working bits
    EOS Utility Console
    Captured Image
The parts that I designed for the Micro Studio are a rough work in progress but they can be found here.  Rotating stage is based on a huge bearing that I had from another project.  It is really not needed for this one so I have one that can be printed but I have not tested it.  The concept is here though!

Friday, February 9, 2018

Leveling the Moai

One of the two complaints that I have stated in regards to the Moai concerns the leveling process.  Standing a big and heavy printer on its head does not sound like a good idea! I play with a couple of different vats and I have found that they are different enough to demand re leveling (unless you only print at 100um).  This would become a pain...beyond pain even!  As I worked with the printer, however, I was able to come to terms with a decent process.

The first part of the solution was this article being published on the Moai Wiki.  That led to a couple of refinements.

If you are starting fresh go ahead and turn the printer on its head.  Remove the four leveling bolts completely.  Print four of these knobs from Thingiverse.  Note that you need to do some test prints to ensure the knobs fit the bolts securely.  As in you should need to pound them on.  Once each bolt has a knob put the bolts back on the printer and do the leveling with the paper sheet and all.  Turn the printer back over!

The second part of the solution is to print the test file from this article (here is a direct link).  Measure each of the cylinders and record the measurements in your copy of this Google Sheet.  Each knurl of the knobs that you now have on your printer represents 1/8th of a turn.  With practice you can turn these knobs pretty precisely just by feel.  You can also do this through the opening where the vat sits and without removing a side panel from the printer!


As always, remember to take the build plate off the printer before removing the vat!

The final part of the solution is to come up with a way to roughly level things without turning the printer over.  Here is my technique.  Set the Z Reset Position to something like 985 or so.  Maybe even lower (which means the plate will be further from the PDMS).  Let it move into position.  Note whether or not the platform moved when the build plate settled.  What you are looking for is the first point at which you detect movement.  The Z Reset Position that I use is the one that is one lower than the first movement one.

IMPORTANT NOTE:  When the current version of firmware starts the Moai it does so with a raise of the build platform and then a tilting of the vat.  Why this order is inexplicable to me!  It will harm your PDMS and should be the other way around.  Lacking that you can protect your vat by starting a print and then turning the printer off after the initial tilt starts and gets PDMS separation.  When your turn your printer back on it will be gentle to the PDMS.

Sunday, January 7, 2018

Printer #5 (Though Only Temporary) - Peopoly Moai

Not the printer but rather the number of them!  Have added a Peopoly Moai to my collection of printers.   That means that I now have three different technologies represented.  Fused Deposition Modeling (FDM) in the case of the Ultimaker 2+ and 3.  Direct UV Printing (DUP) in the case of the two (going to one) Wanhao D7s.  Now with "traditional" Stereo Lithography Apparatus (SLA) for the Moai.

The Moai was attractive to me for a couple of reasons.  First and foremost because while I have enjoyed the Wanhao D7s they are not as dependable as I would like.  Second, because of the positive reviews from its small but enthusiastic user community.  Third, for the price point.  Fourth and finally, because the laser spot size of 67um.

Following is a brief review of my experiences with this printer in three sections:  the kit experience, design and component quality, and finally operation.

The Kit Experience

I was not sure what to expect from this kit but was very pleased by the experience.  The parts were all clearly labeled and the instructions were relatively easy to follow though I strongly recommend augmenting them with this video guide.  A five hour assembly is promised but I did not expect that to be the case (for me anyway).  It probably ended up taking me ten hours which is more to my slowness than anything to do with the kit.  I have subsequently read a post where someone actually beat the five hour estimate on a first build!

I think the printer looks good against a background of Ultimakers!  I don't have much else to say about the Kit Experience.  It was a pretty straight forward process and proof was in the pudding after doing a test print almost straight out of the "box".

Design and Component Quality

It is not fair to compare my Wanhao D7 experience with the Moai given the price difference but I will anyway with that caveat.  As you would hope the Moai is a world apart from the D7.  I would put the quality of the printer closer to that of my Ultimakers than I would to any of the three "clone" printers that I have owned.  One major difference to the D7 is that people seem to be able to reliably share profiles for resins as there is not the wild variability between lasers as we see between UV LED arrays.  This suggests a tighter attention to quality control for the Moai components in general.

On the hardware side, the frame is solid and further stiffened by the exterior plexiglass panels. Everything seems to be well designed and well engineered to fit together to provide a sturdy and rigid structure.  The enclosure does, however, seem to be a fair bit larger than it needs to be for the size of the components stuck inside of it!  This all adds weight which goes to my first concern about the Moai.

Leveling the printer is slightly complicated by the process that starts with "turn the printer over"!  This is a printer, btw, that weighs nearly 20 kilos.  I am not sure how the leveling process should be done but it feels, to me at least, that this is a distinct area of improvement for the Moai.

Operation

Operation of the printer is very straightforward.  You insert an SD card, click on print, select a gcode file generated by Cura, and you are off to the races.  Beautiful print on the way.

This is, of course, unless you are switching resins and want to change the laser setting.  You have to do this via the firmware menu?  Wtf?  Why does this not come to the printer as temperature on gcode is beyond my paygrade to understand at this time though I have asked on the forum.   This is not at all a show stopped it just adds a cumbersome step to your workflow that does not need to be there. 

The bottom line is that the firmware that drives the Maoi is not as advanced as the hardware.  Don't get me wrong, it works and seems to work well, it is primitive!  The above is the biggest example but there are other things that could be improved:

My first wish, as stated above, would be for the laser power to be adjustable via the gcode print stream.  Extruder temperature?  And while that is being done do the same for the other settings that are adjustable and have an impact on print quality

My second wish would be to have an estimated print time displayed

Third wish would be for the knob to be reversed so that turning it clockwise results in a change up...as I believe is standard with most things?

Fourth is to add a menu for printer action controls.  Home, Print Position, Peel (Up and Down), Peel (Leave Down), Jog  Platform Down, Jog Platform Up.

Finally, given the above, a whole new menu structure would be nice!  Maybe three main items, "Print", "Setup", and "Control"?

Support and Community

I will close with praise for the support that Peopoly provides and for the active, and helpful, community around the printer.