Month: December 2023

3d printing gotchas, tips and tricks

3D printing, additive manufacturing, fused deposition modeling…it’s a bit of a minefield at times. So a few random tips, collected as recalled or experienced…

In your slicer, find the first layer speed setting and cut it to 50%. The first layer is crucial so make sure it gets laid down properly. PrusaSlicer and Cura both offer this so take advantage of it.

I hope this link doesn’t go stale: it’s a much better way to dial in a first layer, especially for the Prusa with its live Z offset. Takes just a few minutes and is better than the supplied first layer calibration or any home-brew array of squares at different offsets.

Adhesion issues on metal beds can often be resolved with soap and water…a drop of dish soap, a good scrub with a scouring pad, rinse and dry. It’s not a bad thing for glass beds either. Get in the habit of doing that at the start and solve adhesion issues before they start.

Bed leveling is easier with receipt paper, that thin thermal stuff you get from most stores these days. Thinner than copy paper and easier to work with…(h/t my much more experienced 3D model making pal Ken)

Metal beds > glass beds, for me anyway. Easier part removal through faster cooling and the ability to flex the bed and pop the pieces off.

Slower/higher quality is better. The time for a print to complete happens once. The moments when you look at something rough and raggedy-looking last as long as the part does. Go for quality.

As a test print/project, find the tool holder for your model on whatever model site you like and make it. Having those tools handy is good and it’s a good test of the machine’s capabilities. More useful than a benchy…

A camera to monitor the process is good and if you are going that far, may as well go with Octoprint. See an earlier post on that.

On purchasing choices…

Having worked with machines from AnyCubic, Creality, and Prusa (loaned as it wasn’t working), I would buy AnyCubic again before the others. Dual Z-axis machines > single Z, for stability and alignment. More expensive, as you need another motor as well as the hardware, but one less thing to worry about. Only the Prusa MK3S  has bed levelling (a misnomer: it doesn’t level the bed so much as map it out and work from that map) but that doesn’t mean I have never had to mess with the setup. As much or more than the other two; in fact I would say more than the AnyCubic i3 Mega S, the least sophisticated of the three.

The Prusa and Creality Ender 3 are quieter: the Prusa is silent when it’s not actively working, as as the Mega S now that the internal fans have been replaced with Noctuas. Noisy while working but silent once they cool down. The fan on the Ender is all you hear and the internal fans cannot be turned off with gcode commands so replacing them may be on the agenda.

AnyCubic and Creality both offer machines that can sell for  as little as $100. You don’t get automatic feeding or runout detection at the low end but you can live without those. And they can be added: all these machines are hackable. Bed leveling/mesh mapping can be added as well.

The Prusa MK3S looks and sounds like a great machine and when it worked, it was great. Lots of control/visibility into the process, adjustable speeds and temps and Z-offset, plus active firmware development, all good things. But I have some to think of it like an old European sports car…great when it works but plagued by gremlins when it doesn’t. A naff thermistor meant the bed temps were low and uneven which made adhesion touch and go. The extruder has issues with blobs and uneven filament deposition which either would leave turds on the work pieces or worse, knock the pieces over by being unable to clear the layer at which it was working. Took awhile to work that one out but I haven’t found a solution or anything beyond that symptom.

The Ender was beset with manufacturing issues. The Z-axis had to be shimmed with cardboard (helpfully provided in the packing materials) before the extruder would move freely. The adjustment of the X-axis is a bit subjective which can be confusing. The bed needs regular leveling, sometimes between jobs on the same day. Not sure it that the X-axis sagging or if the bed is actually drifting. A dual Z-axis machine would be better but also not $100.

The AnyCubic is ugly, has a crummy touchscreen interface (a natural fit for Octoprint), unsupported/has old firmware, but with the replacement of the glass bed for a magnetic metal one and the replacement of the internal fans, it’s actually pretty solid. Noisy — the steppers and controllers sound almost musical — and the UI is annoying: you still have to use it to load/unload filament. But it does have automated loading and runout detection, as well as being a dual-Z machine. You can upgrade firmware but my one attempt at that rendered it inoperable for 2-3 weeks until I was able to revert whatever happened. I think I will leave it alone.

For all that, it’s pretty reliable. The bed doesn’t move/need adjusting, it came with a spare hotend and a better set of tools that other two machines, and it mostly just works.

a better argument for basic income would be hard to find

Andrew Goodacre, the chief executive of the British Independent Retailers Association said the cost of living crisis had made people “think of alternative ways of sourcing items that are essential to them”.

Yes, essential items…like food. This verbiage could have come from a business plan or some other document no one is expected to read. But this was a quote provided to a newspaper so here we are.

What if — instead of failed schemes like the derisory  “eat out to help out” — HM Government simply gave its hungry citizens money…money they wouldn’t keep, wouldn’t hoard or send offshore but would spend on those essentials the anodyne Mr Goodacre mentions above. Anyone who has any experience in the real world of economics, which excludes most of HM Government or the US congress, money at that level doesn’t have owners, only spenders ( © Omar Devone Little). Any money you give to the people mentioned in the article will be in someone else’s account, some store’s till, within 24 hours.

Not like I expect Labour to pick up this ball and run with it but maybe after they get in, they can start a scheme like this for the neglected cities of the north and elsewhere.

 

 

Octoprint, octolapse and friends

A time lapse from Octoprint/octolapse:

To make the magic happen, you need a Raspberry π board with PSU, an SD card (8Gb is plenty), and a camera. All of that can be had for well under $100, closer to $60 if you are careful. The Raspberry π cameras are fine but other options exist from Arducam and Inland. I have had three Raspberry π cameras fail in a month so I am not inclined to advocate for them. An Arducam model I bought to test worked first time and has given me no trouble. They both fit in the same size case and as bonus the ArduCam has a status light to let you know it’s working.

If you go with Raspberry π, the Camera Module 2 is what you will most likely want, as it is well-tested and supported. If you find the camera does not work or that the Raspberry π board doesn’t see it as connected, reboot the board and see if that clears it up. The command line methods for detecting the camera are not available if OctoPrint is running, so lsmod and friends are not there for you. But by the same token any Linux or other FOSS experience you have will come in handy.

You’ll need a case for the Raspberry π and the camera…so many options. I chose this one which has versions for the 3 and 4 boards. For the camera mount, I recommend something that mounts to the X-axis and can be adjusted to frame different points of view. For monitoring active jobs you want something that will cover the full print bed but for time lapses you want to shoot straight across the X-axis. Aiming straight back on the Y-axis or at 45° also work, if you can find a mount that allows it.. You might want to choose an articulated model in that case since the time lapse process will push the bed into the shot on each layer change. So something like this if you don’t want to make your own. Look on thingiverse as well…the kind that clip onto the QR code on the Ender are a good choice.

Which Raspberry π should you get? I have tried the 3 and 4 and have no preference. A model 3 with 1Gb of RAM is perfectly fine and at $35 (currently) it’s pretty friendly. The 4 can be had at the same price, if you can get one. The one drawback for the 3 is the USB micro B PSU, where the 4 and newer models use USB C. It was an issue for me as the case I initially chose for the 3 didn’t allow the PSU to be plugged in easily. The 4 is about $20 more at this writing (with 4Gb RAM: not a lot of choices sometimes, they are often in short supply).

You will need a USB cable to connect your Raspberry π to your printer. Many of them use the A/B type like a conventional printer so you likely have one. The Ender also uses the Micro B 🙄 so you may need to get one of those. Monoprice is a great place for cheap cables and has all kinds. Here’s one for $1.49.

Getting the Raspberry π imaged and setup and octoprint installed is documented at the Raspberry π site and at Octoprint and will be more up to date, but the short summary is to download the imager from Raspberrypi.com and let it set up your SD card. You can set up your hostname for the Raspberry π, your login info, WiFi credentials, and all of that in the imaging process. Put it in the Raspberry π board, and fire it up, do all the setup that is documented at Octoprint. Once it’s installed and you have logged in, install the Octolapse plugin. Hit the wrench icon to set up OctoPrint for the printer it will be controlling.

In the OptoLapse plugin these settings should deliver a timelapse video with the extruder out of the frame, letting the workpiece appear to grow out of the build plate as in the video above. Lighting and framing might be bigger challenges than the technology.

You can get more sophisticated with snapshot commands embedded in the gcode but I have not explored that. You will need to step through some options for OctoLapse (in the OptoLapse tab) based on the slicer you use: the automatic setting doesn’t actually work. OctoLapse will cancel any job you submit if you don’t fill out all the information about layer height, retraction distance/speed, etc. Save yourself some time and hassle by doing that.

If you use different slicers (Cura vs PrusaSlicer, for example) it might be worth setting different printer profiles that take that into account. So you may need separate Ender/Cura and Ender/PrusaSlicer profiles as the printer destination. That way OctoLapse knows when to trigger the snapshot function regardless of how you created the gcode file.

 

jobs are not work: a proposition

I have been seeing these monthly jobs reports for years — decades — and have always questioned what they really mean.

Total nonfarm payroll employment increased by 199,000 in November, and the unemployment rate edged down to 3.7 percent, the U.S. Bureau of Labor Statistics reported today. Job gains occurred in health care and government. Employment also increased in manufacturing, reflecting the return of workers from a strike. Employment in retail trade declined.

Did 199,000 people suddenly join the workforce from somewhere else? Were they in school or somehow out of the market? And are the new jobs a net gain or are there some losses that offset them? There is a lot of detail in these reports and perhaps some of these questions can be answered. For instance I have often wondered about earnings…are these “new jobs” good paying jobs or are they lower-wage replacements from jobs that are no longer available…

In November, average hourly earnings for all employees on private nonfarm payrolls rose by 12 cents, or 0.4 percent, to $34.10. Over the past 12 months, average hourly earnings have increased by 4.0 percent.

12¢ an hour over 40 hours isn’t a lot but it’s more…more is better.

But the bigger question I find myself drawn is, what is a job anyway? Maybe I have read too much David Graeber — or maybe not enough — but that’s where I think this is coming from.

Jobs are not work. Let’s establish that. We all do work that isn’t paid, whether it’s household tasks or childcare or meal prep, for others, it’s work that has to be done, just like the work we are paid for. There is a lot of work that needs to be done, public service like education or park maintenance or caring for those who are unable to take care of themselves — the very old or very young. Is that work being done to the extent it’s needed? Ask anyone who works in the paid workforce in those sectors and they will tell you there is more work than they can find workers for, and even with willing volunteers, there is work that is left undone.

So what is a job? A job is a tranche of work that can be monetized and sold in the market. This often means it comes with a performance requirement, like some number of hours to cover benefits and taxes, the costs of doing business which is how these jobs are created — to enable businesses, in most cases. So jobs are commoditized labor, not unlike the collateralized debt that was at the root of the 2008 housing crash. In that instance, risky loans were underwritten by the finance industry and wrapped up in bundles, then sold as assets themselves. No one knew what was in the bundle, but the underwritten value was taken at face value with results we all remember.

I see jobs as commoditized bundles of work, in much the same way, but mostly without the risk. We have often heard someone talk about wanting to hire staff but the hours are not there; in other words, the costs associated with adding someone to the payroll are too high in comparison to the revenue gained by adding them. It might breakeven at 20 hours a week or even 10, but most jobs are 40 hours week, with anything less than that coming with reduced benefits and the general sense of not being a full member of the staff. Part time comes to mean a partial person, as far as status goes.

So how we more clearly delineate the idea of work from our concept of a job? You could work all day long collecting trash or cleaning public spaces but if someone asks you if you have a job, you would have to say no. You could volunteer at a school or senior center, tutoring or managing appointments or any number of really useful tasks but do you have a job? Again, it would be no.. since you didn’t get paid for it and because it was not counted in the bureau of labor statistics jobs reports, your work has no value. You will likely be as tired as someone who does any number of the bullshit jobs David Graeber discusses, some of which actually do harm. But you don’t have a job.

I recall a passage from the Millennium Whole Earth Catalog, where someone posits a worker making land mines…imagine that being your contribution to the economy, making reliable ways to make land unusable and impassible using death or severe maiming as the means. And the amount of effort needed to remove them and restore that land to use: that is the byproduct. But that job would be counted in whatever nation’s BLS numbers.

So how do we get to those sunlit uplands? Single payer healthcare would be one way, since access to healthcare in the USA  is linked to jobs and is often one of the differences between full and part time work. When we hear any politician claiming to be a champion of small business, consider their stance on single payer vs corporate healthcare, and how easy it is for someone to get paying work if their employer doesn’t have to weigh the cost of adding them against the overhead of benefits. If you don’t support a plumber or carpenter taking on some help, even part-time, to better serve their customers, you are not a champion of small business.

Consider also that labor statistics don’t included unpaid or volunteer labor. How many Meals on Wheels volunteer cooks and drivers are out every day providing necessary service but uncounted because it isn’t paid? What about school volunteers, filling the gaps that classroom teachers can’t cover with reading or math support for those who need it? We have to remember, the recipients of Meals on Wheels were once members of the labor economy: their jobs were listed in those statistics, just the schoolchildren of today will be doing work that will be included in reports yet to come. Why is the work being performed on their behalf not counted?

The economy is bigger than the remunerative labor market. The root of the word economics — eco — stems from the Greek oikos  which referred to “three related but distinct concepts: the family, the family’s property, and the house.” Ecology and economics both stem from that root, the idea of a system of mutual exchange or interdependence. To exclude unpaid labor is akin to excluding the need for sunlight in a garden because it can’t be purchased.

We continue to learn more about the ecological systems that surround us and Adam Smith’s 1776 book An Inquiry into the Nature and Causes of the Wealth of Nations was just that…an inquiry, an exploration of what he saw as natural phenomena that he wanted to understand and explain (Smith’s book has a similarity to the Bible as being often quoted but rarely read in full or understood). Not a week goes by without some new revelation about an unseen link or process in nature, most often because humans have disrupted it and are now seeing the consequence, whether it’s beavers managing flood control better than the Army Corps of Engineers to flowers evolving to self-pollinate as their insect and bird partners are declining in population.

Maybe the idea of sunlight as the unpurchasable but necessary component to life as we know it is apt. We all do necessary work that goes unpaid and perhaps is impossible to value in any market. We feed each other to fortify each other for the work that needs to be done. Sometimes presence is what’s being given, being there without being busy. And where that is the work, it should be counted. Does this mean that caregivers should draw a salary? I wouldn’t argue against it but maybe the work we pay to have done isn’t worth paying for. It’s always been interesting me that some jobs get wages while others get compensation…I think the work that requires compensation is work that we know is not worth doing (see Bullshit Jobs above), and we admit that we are compensating people for the waste of their precious time spent doing it.

 

 

 

This kid gets it

“When houses are a million dollar plus and an older couple will likely outbid us anyway, we’re gonna relinquish any lingering delusions about homeownership.”

This kind of talk might make holiday get togethers a little tense. Today’s young adults (and some older ones) don’t have a lot to look forward to.

Meanwhile, with a looming recession, multiple ongoing wars, and climate change at a catastrophic tipping point, others voiced doubt over whether the future is even worth investing in.

It’s as if someone in the family already spent the rent and food money on their expensive travel, the very thing young adults are put on blast for.