Many of us were quite enthusiastically awaiting the availability of SpaceX’s Starlink Internet service. On paper it sounded promising. Now first results are in and the reality is far less impressive.
The details
I do not have this service but spoke with someone who does. He lives in Puerto Rico where the broadband option are limited. There’s the local cable company, then maybe some boutique services where you use microwave dishes, and this year, finally, Starlink. He had just a couple users on it. I think the net results are that it basically works, but with a big caveat. It sucks for real-time communication. And that’s precisely what he needed it for.
So you know when you’re streaming a movie, that downloads the movie in six(?) second chunks, so it’s a bit robust in the face of brief outages. But when you’re doing web conferencing an outage is very noticeable. And that’s what they experienced, time and again. Brief outages that interrupted their real-time applications. Perhaps lasting for a few seconds, but enough to spoil the broadcast.
Then one night, knowing their cable provider, Liberty, was out, they tested it again. It seemed fine at night. But during the day next day it failed in the same way – brief, disruptive outages.
Maybe some of it is due to holes in the satellite coverage and will get better as the fleet fills out. We’re not sure at this point.
And, yes, the dish was placed in a place where the app showed something like 98% visibility to the satellites in the sky.
Some interesting screenshots of what a Starlink IP looks like in Puerto Rico
ipinfo.ioipchicken.comspeedtest results
That speedtest looks quite good to me!
Results of Starlink app for this actual user in Puerto RicoRunning PING to google.com shows a single dropped packet
A few words from the actual user
Liberty Cable is not working even after a change of the cable modem. So this past two weeks his household has been exclusively using Starlink. In his own words:
“The single most important thing to consider when using Starlink is how obstructed your northern facing view of the sky is. I am attaching a screenshot from my Starlink app. The red shows the obstructed area. My placement is 2.5% obstructed but I still get an interruption every 4 minutes the app says. In reality it might be every 20 minutes for a few seconds.
“While my Liberty service has been out Starlink has been a life saver for us. A second user can still do her video calls but it will freeze during those 20-ish minute intervals for a few seconds. It’s not the end of the world for her but not totally idea.
“For me, my VPN will disconnect for those same few seconds and then will reconnect. If I’m entering a trade that can be a crucial few seconds while my vpn and software reconnects, but it’s workable.
“The Starlink app is free and available for everyone to use. I would suggest that anyone who is interested in the service to first download the app and scan the sky where they think they have the freest point of view north. They will only get purely uninterrupted service if the app registers 100% obstacle-free view. The properties that are most suited for Starlink are the ones at the top of a hill, with a field, or a roof taller than the surrounding trees, especially the trees to the north. An obstructed view like mine is perfectly suitable for streaming movies as they tend to buffer a few minutes in advance, downloading files, and surfing the web. Without a completely obstructed view of the sky, video calls, VPN connection, Remote desktop connection, and online gaming will be interrupted in a frustrating manner.
“I am also attaching a text file of my results from running a ping -t to google.com from my Starlink connection. This test ran for about 25 minutes. The request time outs are the times when the Starlink satellite was not able to connect due to my obstructions. However, also notice that during these times it only lost 1 ping and was immediately able to reconnect. Again, somewhat frustrating but it’s a usable product.
And during Hurricane Fiona?
Starlink performed like a champ during the hurricane. I assumed that coverage would be spotty during the drenching downpour but the user said no he was streaming Netflix. It was just a little more spotty than usual. Now that the island is without power as I write this, his Internet service is as good as usual and the day after the hurricane was a normal (remote) work day like any other.
Conclusion
Don’t throw away your cable modem*. In general as of this writing in June 2022, Starlink is a good solution for those working from home, but be prepared to be bumped every 20 minutes or so from your video conferencing or other real time uses. And of course it’s good for surfing the web or on-demand streaming.
I don’t cnosider this the final word however. There’s still hope. I’ll update this post if the quality of service ever improves.
*Unless you’re one of the many whose cable modem service isn’t all that great to begin with.
If you’ve ever had the misfortune to access a web site in China in your Edge browser, you may find that from that point onwards all your new tab pages display in Chinese despite of your best efforts to eradicate it.
The details
I was in that same boar until today. There are many bad leads out there on the Internet. In fact I never did find the solution on the Internet. I got it from a colleague.
You click on the three dots, go to Settings and search for reset.
Do the Reset. It is a little disruptive, as i have found. It does not delete everything, but it certainly resets some things. As soon as that’s done you will no longer have new tab pages be in Chinese.
My wife was stuck while using the WW app on her Samsung A51 smartphone. She needed to lookup a nearby “studio.” We’ve all seen these forms – you enter a zipcode and up pops their nearby locations. But in this case there was a problem. No keyboard was popping up! Instead the bottom of the screen below the search field was filled with some blather which we could not get rid of to reveal the presumably hidden software keyboard.
The (kludge) solution
Please note that I am a specialist in doing things the wrong way that manage to get it done. I noticed the field still permitted long touch, and hence paste (from the clipboard). So I told her to enter the zipcode into another app such as Evernote, copy that text into the clipboard, return to the WW app and paste it into that field.
And do you know – that actually worked!
Conclusion
So if you’re in a jam and just need to fill out a field on your Android phone but your software keyboard isn’t appearing, a way out is to paste the desired content from another app such as Evernote or Onenote.
I’m sure many people have faced this. You like to query your Echo Dot for basic information and you’d like to take it with you and work in your hotel room so you can get the local weather, etc. But then you are foiled by the setup process until you finally give up after trying to discover it as a new device numerous times.
I was in that exact situation last week. Finally I thought of something that broke me out of the discover device loop, so I wanted to share that.
The details
A hotel will typically offer Internet, but through a “captive portal.” This means, technically, the password they provide you at the front desk is not the SSID password, but a password to their portal’s web site. So it is technically not part of the WiFi information. That’s what makes it so hard for dumb devices like the Echo Dot to get past that page.
Normally you go to your room after checking in, and you perhaps set your phone to use their WiFi after dutifully logging in to the portal page. Then you get around to setting up your Echo device. I could not manage to finish the Echo Dot configuration under those conditions last week, though I tried many times over, including manual setup.
What I realized, though, is that it might help to start clean. So I “forgot” the hotel’s SSID (WiFi) on my phone. Then I was only using 4G communication. Then I went through the Device Setup in the Alexa App on my phone. At some point you get asked which WiFi to connect to, and you get redirected to the captive portal, where you put in the information. In other words I stumbled my way through it. But then it did work.
So I’d say the upshot is to configure the Echo Dot first before setting up your phone to use the hotel’s WiFi. I’m not sure it will always work, but at least it did work once! But if you did things in the wrong order go to your WiFi settings and “forget” the hotel’s WiFi – it may have the same effect.
2nd test – successful
Since I’m supposed to be the expert I had the opportunity to try my own technique at another hotel. It was about 10 minutes of stumbling, but then it did work in the end. Maybe my tip helped, maybe not.
As I do not have the straight recipe, you have to be willing to try different things. Pay special attention to whether or not your setup device is connected to the Dot’s WiFi (amazon-dkd or something like that) or not. That’s generally a good thing. Then you have it (the Dot) search for available WiFi networks. I guess. It’s confusing. You’ll probably need to put your Dot into setup mode mulitple times. Esimated time to stumble your way through it: 10 minutes. You can decide if it’s worth it or not.
Other ways
I’m thinking about mac address emulation, i.e., temporarily emulate the MAC address of the Echo device with a more amenable device, and do the poral login. But I haven’t had time to research it. I will post it here if I ever figure that out.
This book is mainly about what to make of the very unusual sighting of an object which came from outside our solar system in 2017, dubbed ‘Oumuamua.
This book is written at a very simple level – perhaps fifth grade or sixth grade? So I guess it’d be a great addition to a middle school library. I was aching for some more details.
I’m actually ready and willing to ‘believe.” For me the main thing was the paucity of facts presented.
The biggest failing of the author is to fail to be so guarded! Professor Avi, you are uniquely qualified to spin any plausible story about this object. Surely you have thought of many origin stories for this thing. Why not share them? This is a book, after all, not a scientific publication. We won’t peer review you for daring to create a plausible backstory for this object.
For me to make my points I have to give some background so everyone sees what I am seeing.
Professor Avi has this super cool lightsail project. Something like 10 GigaWatt lasers are required to send a super slender light sail up to 1/10th the speed of light.
An aside. Wouldn’t a multi Gigawatt blast create a plasma out of the atmosphere, thereby transferring its power to the air rather than the target lightsail? Maybe you overcome that by spreading the laser over a wide area. or using micosecond blasts. Not sure. And what about the reflecting rays? Can they be adequately disbursed to avoid singeing the earth?
But I digress. Sending any macro object to any fraction of the speed of light is wondrous. And dangerous. By conservation of energy I have to assume the thing at that speed would have 10? 100? gigajoules of energy (I will do the math later). Imagine the consequences of an earth-like planet being “visited” by one of those things. Either cataclysmic, or at least terrifying to those lifeforms. Yes, I know the odds of collision are infinitesimal. But they are not zero. And no way can these things be aimed with such precision to avoid that scenario altogether. Not to mention the idea is to send thousands or millions of them out. Welcome to mankind, extraterrestrials, we like to announce our entrance with a bang!
For instance, ‘Oumuamua, though it comes from outside our solar system, is at the local system of rest of the nearby stars. So that is pretty remarkable, and it means its speed is not anywhere close to a fraction of the speed of light, unlike Prof Avi’s lightsails. Why is that? This particular civilization felt they could wait around thousands of years?? Or did it start out at a fraction of the speed of light and then get decelerated as it neared its target? And if so, by what force?
And when I learned it sped up as it zoomed around the sun, I immediately thought of the analogy of our space missions which sometimes use giant planets like Jupiter to pick up speed and slingshot away faster than they had been going. Was ‘Oumuamua purposely aimed near to our sun for its boomerang effect? But it was tumbling like every eight hours. Should lightsails do that? Or does that show if it was a lightsail, it was no longer fit for purpose – inactive space junk? ‘Oumuamua trajectory deviated in the manner a lightsail might. But if it was slowly tumbling, how is that compatible with that statement? Aren’t lightsails only good for catching rays from one orientation? I actually don’t know but that’s what I would naively assume.
And it came from somewhere. if you reverse its trajectory, where did it come from? Was it an area with an inhabitable exoplanet?? Is that area receiving heightened scrutiny from SETI and company??
Going back to these lightsail things travelling at a good fraction of the speed of light, if one were to whip past us, would we even have a chance to see it? I believe it would be effectively invisible to us. How would they fare when colliding with space dust?
A manufactured lightsail would have great symmetry. The brightness profile was not a nice sine function, though close. What is the lightsail shape we can assume given the observed brightness profile fluctuation? A partially destroyed lightsail, perhaps? Where is the artist’s rendering of that?
So you see my point now? Don’t make me speculate. You’re the expert. Your speculations will be grounded in better science than anything I can dream up. So I guess Prof Avi, despite being a maverick in many ways and bucking current scientific thinking in promoting this as a thing created by alien life, reverted to the usual scientist’s conservatism in not making unprovable statements. And we are worse off because of it.
The great filter
And this term bothers me. It reads poorly. The first I heard it was from a fellow reader, and, even though I was familiar with the concept, I had to ask for a definition. A good term of art is self-explanatory. This is not a good term. Advanced civilizations probably last for only a few hundred or at best a few thousand years before they self-destruct. Looking at ourselves, we’re probably only going to get a few hundred the way we’re going. And this is supposed to be the great filter or something? I don’t have a better term, but far more clever people could come up with one I am sure. Like inevitable self-destruction, except something with more of a ring to it.
So I was asked, if this comes from an advanced civilization, is this a cause for hope, or a cause for despair? To argue the despair first, we got space junk from an advanced civilization. Probably they died out and we are left to do astroarchaeology on their junk. Not so great. But I am more hopeful. It’s incredibly difficult to target another star, they managed to do it. Maybe their lightsail had an accident or something. No worries because they sent out millions more like Prof Avi proposes to do. And, the main thing, we overlapped with them! We were advanced enough to detect another’s technology. Mostly because of the self-destruction tendencies, and the randomness of when advanced life forms, we’re not going to have any overlap with the vast majority of our fellow aliens. Their time in the sun was either way in the distant past, or will occur way in the future. That we overlapped in any way at all, probably means there are very, very many advanced civilizations, even in our stellar neighborhood, such that we had decent odds of intercepting and overlapping with one. And that gives me awe and excitement to learn about this advanced life. The hope comes from the viewpoint that these beings aren’t threatening to us. I have a naive belief that they would be trained in cultural sensitivities a la Star Trek The Next Generation or something as opposed to Independence Day, and decide not to wipe us out, nor to alter our technology (much), but more to observe us from afar. So on balance this encounter makes me hopeful.
Any insight if this was a civilization which reached the singularity? I.e., where it transferred its organic intelligence to a program in silicon or some other infinitely long-lasting, purpose-built medium??
So yes I am convinced the simplest explanation is the best one, and prof Avi’s hypothesis is by far the simplest. It raises a few questions which I would have preferred answered. And I was dying for more speculations. The speculations of an insider is worth 100 times the speculations of an outsider such as myself who doesn’t know what they don’t know!!
Philosophy
Prof Avi devotes a lot of time to philosophy. That’s all good. I didn’t learn too much from it, but I suppose others could find it useful. I don’t have an issue with it.
Resources
If I were really responsible, I’d do research, or at least read the darn book reviews on Amazon or get an answer to some of my questions on Quora or something. Probably a lot of my questions are addressed. But my time is not infinite and I’m not trying to impress anyone. As I learn more in the course of my ad hoc reading I will revise this blog with better information. And one more thing about my personal philosophy, I am writing this based solely on self-reflection and readings I’ve absorbed from years ago. I consider active research “cheating” in this regard, and I will inevitably be swayed and biased by the first educated opinion I come across.
Before reading this book, I was aware of this object from 2017 and that it was special, just based on my general reading of science news. It was only from this book that I realized how compelling the extraterrestrial case was.
Prof Avi took a few facts and made a book out of it. He should probably create a fictional but plausible back story for this object and make another book that addresses some of these basic questions.
February 2022 update
They have just discovered signs of a third exoplanet around Proxima Centauri, our nearest neighbor in the galaxy! That’s exciting. The place is only four light years away. Maybe a lightsail craft will visit it within our lifetimes.
With the advancements in technology, there are now many features that allow for seamless connection between devices using wireless connections. One of the things that allow this is smart TVs. Currently, the market for them is dominated by South Korean company Samsung. 39% of all sales come from them, which is a huge number in comparison to the 19% from LG and 9.3% from Sony.
There are also devices you can attach to your traditional TV to give it the functions of a smart one, so you won’t have to spend too much to upgrade. With this kind of TV, you can do many different things like stream from platforms like Netflix or Hulu, or even mirror the screen of a mobile device.
What is screen mirroring?
Screen mirroring is basically the ability to project what is on one device to a TV display. This is normally done through the internet and is comparable to connecting a laptop to a monitor using an HDMI cable. As mentioned earlier, there are different ways you can do this. Some TVs have built-in software that allows you to do this, while some use different hardware attachments.
Examples of these accessories are the Amazon Firestick, Apple TV, and Google Chromecast. The last two are some of the most popular ones on the market right now and they both have their own pros and cons. For those already in the Apple ecosystem, using the attachment from the same company will make connecting them easier. If you are looking for a cheaper alternative that can work on almost any device, the Chromecast is your best bet.
These accessories work because of their internet connection. The circuitry is specially designed to deliver signal integrity which ensures that digital and analog signals do not become distorted during propagation. Moreover, this guarantees that the signal can be recovered if temporarily lost, and that screen mirroring is smooth and won’t experience delays.
How to mirror your screen
Make sure your devices are connected to the same internet source
As the feature heavily relies on connection, the only way you can display what is on your other device is by being on the same internet source. Go to the settings of both of your gadgets and connect them to the same wi-fi line. This will make them identifiable to each other and make mirroring possible.
Read the instructions
If you are using a TV box or tool like the Apple TV or Chromecast, make sure to read the connection instructions on the manual. For example, the former requires you to use AirPlay and the manual should teach you which buttons to press on your phone or laptop. For the latter device, you might need a third-party app like the Google Home One to be able to get the accessory to mirror. Be sure to check the instructions given so you can make it a more seamless experience.
Check your Wi-Fi’s integrity
Because mirroring heavily relies on your internet, if the integrity (or speed) that your Wi-Fi is giving out is not enough or lacks bandwidth, you will have a lagging experience. Before you start, try to check the speed of your internet to be sure that it is strong enough. You can simply go on speed test sites on your browser. A good speed would be at least 25mbps, so if it is lower than that, you might not be able to connect or mirror easily.
Screen mirroring is just one-way technology has made life more connected. Gone are the days when other wires and connections were needed. The internet now enables you to perform tasks like projecting from a smaller device to a bigger one, hassle-free.
I am kind of annoyed that my simple problem with a Dyson Animal vacuum cleaner took way more Internet research than should have been the case to resolve. I hope to spare someone else that grief.
The details
Actually this is a friend’s vacuum cleaner. I don’t think it would have played out this way had I been the exclusive user of it. She noted that it stops and starts. It goes for a few seconds and stops. Then you can start it up for a few more seconds. And so on.
More clues
This model shows the charge remaining on the battery. Still two bars out of three, so that’s good. It’s been properly charged. After examining it I get the gut feeling that the brush motor shouldn’t draw all that much power.
We also note that when the long tube is removed and its just acting as a short hand-held device, it doesn’t stop.
After doing some Internet research (not finding an exact hit for this model), I am inspired to take things apart and check all the filters. On other models the filters can do you in. This one has been very lightly used to date and so the filters are remarkably clean. No filter issue.
The solution
So I check the brush and that area. It is simply clogged with gray dirt. I begin to clear it out with my fingers – seems no easy way to do it – until all the gray dirt is gone from the brush area where it goes up into the tube.
The results
The results are in. Works like a champ now!
Comment
I am more used to a more obscure brand of vacuum cleaner, Miele. It has a simple orange status thing that visibly shows you when it can’t suck in dirt or what not due to a full bag, a clog, whatever. In addition you can pretty much hear the pitch of the motor’w whine increase when there’s a clog. With the Dyson I didn’t notice that pitch change, nor was there any indicator of a cloged system. So Dyson’s design is faulty.
Conclusion
A Dyson Animal vacuum cleaner was only running for a few seconds at a time. After a few more seconds it could run again. The power level showed two of three led bars. The filters were all clean, but the brush head was clogged with dirt. Cleaning that out fixed everything nicely.
Dyson’s design has to be faulted for not making this clogged situation more evident. Strange, coming from a company which obviously prides itself on its innovative design.
While watching Mad Men last night on IMDB we saw a terribly annoying audio delay – probably about three seconds after the video. Then it cuts to the commercials and they were perfectly in sync. Then back to the show – still a 2 – 3 -second delay. Is it the brand of TV? We use a Firestick plus a Samsung LCD TV.
The solution
Well, my first inclination was to look for audio settings on either the TV or the Amazon Firestick which might be set to delay audio. I had such a setting on an old sound system, though I think it was only for a sub-second delay. But, there are no such settings on either Firestick or Samsung TV, so that’s not it.
An Internet search proved not too useful.
What I eventually realized – the in-sync commercials was a hint – is that I could rewind the show a tiny bit, and that might pop it back into sync. And…it did!
How it happens
I think it happens when I pause a show one night, to return to it a later time. It remembers where I was, which is great. But it sometimes gets out of sync this way. I have seen this with Netflix and IMDB. The common element seems to be the Firestick.
We woke up yesterday to no Internet. The usual remedies consumers go through did nothing to resolve the issue. What to do?
The details – November 25, 2020
The usual restarts or my router and the cable modem did not work. I plugged in my work laptop directly to the cable modem for some quick tests but that did not work.
I plugged my work-issued VPN router directly to the cable modem and it did not pick up an IP and re-establish the tunnel.
When I logged into my router I saw that its WAN IP was listed as 0.0.0.0, which means none at all.
I called the ISP twice. Both time they said they could “see” my modem, and they tried to restart it on their end, but that did not seem to do anything at all, based on the constant status LEDs (see picture below). I got my service visit moved up from Dec 11th to Dec 2nd, but still that would mean a week without Internet – not so great when three people are relying on it for their work.
I rebooted the cable modem a couple times at least. Nothing changed.
Then I started some research on quickie alternatives. Ask a friend from work for a spare Cradlepoint air card? They’re already out on vacation. Get a Chinese-made unlocked hotspot with pre-purchased data? Seems fishy, and ultimately expensive. Verizon brand hotspot? We had a borrowed one. Very finicky. And no ethernet ports.
Raspberry Pi + DIY approach?
At one point in the evening, convinced I would have to wait days for for a visit from the cable guy, I rigged up a spare Raspberry Pi to act as a router between a mobile hotspot (a companion tablet to a Verizon phone) and my Linksys router. Why bother? Why not just use the hotspot directly? Mostly because it’s a pain in the rear to reprogram all those Internet of Things devices one has in ones home these days, notably the several Echo Dots, but as well, a wireless printer, a few laptops, Firesticks, tablets, etc. With this approach I keep the WiFi SSID as it was for all those devices. And, it sort of worked! At least I got one Echo Dot to work. I didn’t push my luck. This stuff consumes a lot of data, even when “idle.”
To be continued…
Linksys WRT1200AC status lights – when healthy!Cable Modem tatus lights – when operating normally
But I am pretty good at troubleshooting. What I know that less experienced people may not is that all the testing I’ve done to that point was not ironclad proof of failure of the cable modem. I know the traditional advice of old is to hook up a laptop directly to the ethernet port and work with it that way. Furthermore the cable company support said that my status lights were reading normally. So, when I tested my work laptop? Are you kidding? That thing has so many problems when I switch between SSIDs due to some new security software – it loves to display the Globe in the system tray, and the only recourse is to reboot. That’s what I was seeing, but notice I said a quickie test? I did not have time to do that reboot and all that. And that work-issued VPN router? I don’t know how that thing really works either. Never having set it up that way I did not trust reading too much into its results (which was essentially an orange status light instead of the usual white).
So when I had more time in the evening, I hooked up a home laptop which I know should work. After a cable modem reboot in fact I did get an IP and could surf the Internet. That was a glimmer of hope. So I put my router back in place. Still it did not pick up an WAN IP address. Still reading 0.0.0.0 for its IP.
Then I put the laptop back, writing down the IP, subnet mask and default gateway. Then I put my router back, switched its WAN mode from DHCP to fixed IP, putting on the exact IP address the laptop had picked up, with correct subnet mask and default gateway. Still it was not working. When the router is not working the WAN status light is sort of orange-ish. It’s white (pictured above) when the WAN link is communicating.
I decided the fault should lie more with my router than anywhere else, and since it wasn’t working and no number of power cycles was changing that situation, I decided that a factory reset is the thing to try. The last thing I could try. I noted the exact name and passwords of my SSIDs, held the reset button for 15 seconds until the status lights flicked out, and let it start up. It went through a start-up process, which i saw after connecting to its default IP of 192.168.1.1. It was clear it was not seeing the cable modem at the point where it should, but it had some very specific advice to try: power off cable modem, wait two minutes, power it back on, and then it would try again. And that did work! Yeah!
What may have precipitated this
My local cable company was recently bought by a much bigger company. I know for a fact what my WAN IP used to be, and I see it has changed. They now draw from a giant pool of IPs – a /14 in CIDR notation – that’s 262,000 addresses – that belongs to the new owner. So I believe the problem occurred due to a poor implementation of the dhcp protocol within my router, or a poor interplay between my router’s DHCP client and the ISP’s DHCP server. But I can’t research that line of troubleshooting because the ISP’s DHCP policies would require a lot of time-consuming experimentation on my part to reverse engineer based on observed behaviour under different conditions. And I would need an open source DHCP client – but I have the Raspberry Pi running dnsmasq for that, so that end could gather all the needed client information.
Prior to this acquisition I would tend to keep the same WAN IP for years – that’s how stable it was.
Another approach
Very germane to this topic is the fact that my neighbor down the street experienced his own Internet outage the day after I did! His solution was to buy a better cable modem. I did not know you could do that – I thought they were proprietary. He also saw his router with the 0.0.0.0 WAN address. And his approach also worked. This makes me less sure my router was really at fault – maybe Altice screwed up their DHCP service for half a day.
Conclusion
Unusual for me, I’m going to write the conclusion before writing the tedious part which is the full explanation in the middle.
By the end of the day I got the Internet working. After isolating the problem to my home router, the Linksys WRT1200AC, and determining that any amount of power cycling was not clearing things up, a factory reset did the trick! The cable modem and my cable Internet service was fine all along.
Intro The end pieces of the pergola above my deck kept blowing off. I finally lost track of them and decided to 3D print a replacement to keep my skills fresh. I will use this as an opportunity to review my process for 3D printing.
The details For people like me who don’t really know what they are doing, the kinds of objects you can 3D print is pathetically small. Yes, there are sites like thingiverse.com. But there are so many physical constraints if striking out on your own. If the extruder is pulling the filament horizontally it can only be unsupported for, I forget, 1 cm or so. That may be called a bridge. If you’re going from smaller to wider, the angle of increase cannot be greater than 45 degrees though I think 30 degrees is a safer bet. If you can want to violate either of those contraints you’ll have to include supports which you later saw away (yuck).
So those two constraints, combined, kill just about anything you’d ever want to print.
But, amazingly, my endplates could meet the criteria, if I made a slight compromise, so I went for it.
Openscad I use openscad.org’s software to make a mathematical model of the object, built up from primitive geometric shapes (cubes and cylinders, mainly). When I learned you could write a simple program to generate your figure, and see the results rendered, I was like, sign me up.
Here is my openscad code, with some extra unused stuff left over from a previous design.
STL You always make mistakes. The question is if you have the trouble-shooting skills to catch them before committing to printing… Anyway, when satisfied, render your object (F6), only then can you export to STL (stereolithography), which I guess is a universal description language.
Cura Then you need a slicer! I think that translates your shape into movements that the 3D printer needs to make to lay down the filament, layer by layer. So import your STL file into Cura.
I think I set up Cura last year. I don’t want to mess with it. And don’t start playing with your model. It’ll do funny things to it. Just save as GCode. That’s it. Cura kindly estimates how long your print will take, and how much filament it will use up.
Cura will every time propose to upgrade itself. Don’t waste your time. Just say no. If all you’re doing is using it to turn STL into GCode you don’t need the latest. Anet a8 printer It can be a royal pain to adjust the Z axis. Usually you have to adjust all four corners so that pulling a paper through gives just a little friction. The screws and assembly is so bad that you are constantly shifting between over-correcting and under-correcting. In this case I divided the problem in two because the plate was so narrow I just adjusted for the two sides, not all four corners, which is a nightmare. And I’m a little ahead of myself, but I have to say that this approach worked brilliantly.
Transfer the file to the micro SD card. Print, and enjoy! More fun is printing something with a lot of holes. The printer makes the coolest electric sounds as it quickly shuttles back and forth and to and fro. This endplate is pretty boring by comparison and mostly consists of long stretches of material.
End result
side by side
With its long flat section, the thing really adheres to the plate, unfortunately. I slightly nicked a corner prying it off with a screwdriver. But I think that beats the alternative of it not adhering to your plate. I’ve seen that once – and the printed thing just gets dragged around, which is fatal.
My piece came out a couple millimeters short in both dimensions. Still functional because of what it is, but still something I need to understand better.
Industrial design I take it for granted that the PLA I’m printing is not as strong as the original plastic, so I should compensate by making edges thicker than needed. But I have to say the thing came out quite rigid and strong. This cheap 3D printer – if you treat it right – produces some high-quality output!
Bolt hole cover In June I decided to print a bolt hole cover, also for the pergola above my deck. Modelling was pretty easy. I used a sphere for the first time to create the curved shape of the cover. Then I had to “get rid” of the rest of the sphere so I swallowed the unwanted portion of it up with a giant cylinder.
Here’s the openscad code.
// DrJ 6/2020. Parameters in mm
innerR=8;outerR=11;plugHeight=2;
epsilon=0.4;upperHeight=2.5;
sphereR=26; big=50;
tinyR=1;
// min facet angle and facet size (mm)
$fa = 1.1; $fs = 1.1;
difference() {
translate([0,0,-(sphereR - upperHeight)]) color ([0.2, 0, 0]) sphere(r=sphereR);
translate([0,0,-big/2]) cylinder(r=big,h=big,center=true);
}
translate([0,0,-plugHeight/2]) cylinder(r=innerR,h=plugHeight, center=true);
Bolt hole cover
I installed Cura v. 3.2.1 to make sure I had a version with support for supports, ha, ha. Most views don’t even show the support. I made sure I had it generate supports. Then I found that the layers view, when you drag it through the layers, shows the supports it will make. Some support options definitely would not have worked, by the way, namely, lines.
But, basically, supports are basically impossible to remove. I pried at it and rubbed with sandpaper but my vague hope that the supports might pop off were badly misplaced. The thing looks like a button. But fortunately the plug part was shallow so I just super-glued the thing onto my pergola and it looks like the real deal at a glance. In fact it looks better.
Mailbox plate
If I thought I was a whiz at this sort of thing, this mini-project proved me wrong. I was going to add a semi-circle at the bottom of a rectangle, and work through Pythagorean’s theorem to find the unknowns. I was just spending too much time and really, eye-balling it was more effective. And a more desirable shape was an ellipse. So the good ones make these parameterized models, but I find it’s not so easy and when you want to bang out some custom part quickly, it may not make sense.
There was a gaping hole in my mailbox post. This plate covers it up. Here’s the code.
What techniques I learned from this simple mailbox plate project
I used the linear extrude method for the first time. Very useful. So, shapes like squares and cirlces (or ellipses) extruded along the Z-asix. My first effort did not include the bump-out, which I needed as a spacer. So I learned that you don’t always have to re-level after every print and this was the first time the dang filament didn’t break on me between print jobs – because I acted within 24 hours. I even re-used the blue tape. All real time-savers. So I used the 3D printer the way you imagine it to be – just there to print stuff, not to worry about fixing all the time.
I also had a reject – a first attempt without the bumpout. I kept it to test the breaking strength. So the thickness is 2.3 mm, right (I have to get calipers!)? It’s pretty darn strong. I was probably applying 10 pounds of force and it was hardly budging. Each layer prints orthogonally and a piece this thin is solid material.
Bird feeder C ring
I have a backyard bird feeder which hangs too low – I fear a squirrel could jump to it. So I wanted a way to shorten the hang by winding the wire around something that will stay. So I designed a C-shaped ring thing. works great. This is a first time for me for using a rotate extrude. I had to chop off the bottom of the ring so that I would not need supports. This is my shortest code yet, and least paraemerized. It’s just easier when you want to knock something out quickly…
// DrJ 7/2020. Parameters in mm
// min facet angle and facet size (mm)
$fa = 1.1; $fs = 1.1; $fn=100;
difference(){
rotate_extrude(angle=348,convexity = 10)
translate([20, 0, 0])
circle(r = 6);
translate([0,0,-9]) cube([60,60,10],center=true);
}
Bird feeder C ring
This is my first piece with interior fill. The bird feeder is pretty heavy – 10 pounds. but this little C ring is plenty strong for entwining the hanging string.
Curved TV bracket
The code
// DrJ 12/2019. Parameters in mm
z=32;
thickness=4;
a=38; // 1 1/2" - the lip
S=174; //6 7/8" - how far to come out
m=127; // 5 3/32" - hole to TV edge
n=13; // 1/2" extra beyond screw hole
o=m-S/2;
r=S/2;
Rscrewhole=2;
t=85; //restraint y from inner claw
u=S-thickness-t;
Rthole=3;
xt=12;
reinforce=10;
bigthick=thickness+1;
// min facet angle and facet size (mm)
$fa = 1.1; $fs = 1.1;
difference() {
translate([-n,0,0])
cube([n+o,thickness,z]);
translate([0,thickness,z/2]) rotate([90,0,0]) cylinder(r=Rscrewhole,h=thickness*3);
}
// staircase
translate([m-a,-S,0])
cube([a+thickness,thickness,z]);
translate([m,-S,0])
cube([thickness,S/2,z]);
//reinforce the corner
shim=bigthick-thickness;
translate([m-shim,-S-shim,0]) cube([bigthick+shim,shim,z]);
translate([m,-S-shim,0]) cube([bigthick,bigthick+shim,z]);
// curved section
translate([o,-S/2,0]) {
rotate_extrude(angle=90,convexity=10){ translate([S/2,0,0]) square([thickness,z]);}
}
// restraint
translate([m-xt,-u,0]) {
difference() {
cube([xt,thickness,z]);
translate([2*Rthole,thickness,z/2]) rotate([90,0,0]) cylinder(r=Rthole,h=thickness*3);
}}
//thickeners
translate([m-1,-u-1,0]) cube([2,thickness+2,z]);
translate([m-xt,-u-1,0]) cube([2,thickness+2,z]);
Waffle tile
// DrJ 12/2019. Parameters in mm
barthick=6;
shaveamount=2;
shavedthick=barthick-shaveamount;
lip=7;
lipandextra=lip+3;
radius=1.5;
z=7;
ytot=190;
//y=ytot-2*lip;
y=ytot;
nbars=5;
xstep = (ytot-2*lipandextra-nbars*barthick)/(nbars-1) + barthick;
// min facet angle and facet size (mm)
$fa = 1.1; $fs = 1.1;
difference() {
wafer();
// half material for tesselation
halfbar=barthick/2;
translate([halfbar,-y+lip,-1]) wafer(z+2);
translate([-halfbar,y-lip,-1]) wafer(z+2);
translate([y-lip,halfbar,-1]) wafer(z+2);
translate([-y+lip,-halfbar,-1]) wafer(z+2);
// holes
ydis=lipandextra-lip/2;
echo (ydis);
translate([0,-ydis,z/2]) rotate([0,90,0]) cylinder(r=radius,h=y);
translate([0,y-2*lipandextra+ydis,z/2]) rotate([0,90,0]) cylinder(r=radius,h=y);
translate([lipandextra-ydis,0,z/2]) rotate([-90,0,0]) cylinder(r=radius,h=y);
translate([y-lipandextra+ydis,-1,z/2]) rotate([-90,0,0]) cylinder(r=radius,h=y);
// shave off material by sitting cube on top
cubelen=y-2*(lipandextra+shavedthick);
translate([lipandextra+shavedthick,shavedthick,z-shaveamount]) cube([cubelen,cubelen,z]);
}
//rotate([-90,0,0]) cylinder(r=radius,h=y);
module wafer(zwafer=z){
for(xs=[lipandextra:xstep:ytot]){
translate([xs,-lipandextra,0]) bar(zwafer);
}
translate([y,0,0]) rotate(90) {for(xs=[0:xstep:ytot]){
translate([xs,0,0]) bar(zwafer);
}
}
}
module bar(zheight=z) {
cube([barthick,y,zheight]);
}
Router platform
Router platform
This router platform consists of two separate printing jobs. Here are the bird legs. Note these openscad files contain a bunch of unneeded detritus.
A friend printed this for me using PETG material. It seems pretty nice. And my design works really well for my singular purpose (shown in picture below).
// DrJ 6/2021. Parameters in mm
barthick=6;
legthick=6;
height=94; // approximate – remeasure
apart=50;
innerringD=32; // 1.25″
boost=innerringD/2 + 4;
fromend=7; // for topbar screwholes
nexthole=26.2;
topbarlen=38 + nexthole/2 + fromend; // 1.5″ back from rod center
radius=1.8; // works with m3 screws
// min facet angle and facet size (mm)
$fa = 1.1; $fs = 1.1;
//lie the whole thing flat for printing with no supports
rotate([0,90,0]){
zigzag(); translate([0,apart,0]) zigzag();
crossbar();
gallows();
}
I need a thingy to loosen my birdfeed. I had been using an allen wrench, but I lost it and it wasn’t quite the right shape – nowhere to put it. So I designed this simple fit-for-purpose object. It features a hook for hanging, a rounded corner and a flat bottom for easy printing.
I should be embarrassed to admit this, but I’m otherwise tech-savvy so I am not. I put my orange USB stick 9flash drive) into my computer in order to copy over my latest GCode, and the computer made that typical Windows double sound which shows you’ve plugged something into a USB port, but the F: drive would not show up no matter what I did.
Well, turns out I had left the micro SD card behind in the printer! It has to be inserted into the back of the USB stick. Duh, right? In my defense I hadn’t printer anything in months and I simply forgot the setup.
How frequently should the print bed be leveled?
I thought maybe you have to do it before every print job. But you see that TV bracket up above? I had to print out five of them as I continued to refine the design (and I was really trying to not be wasteful!). They take five – six hours to print. i would simply print one out after another without re-leveling the print bed. No issues. I did have to press down on my painters tape, which bubbled up where there was contact with the PLA.
Does printing thin, vertical pieces work OK?
Yes. I did a 3 mm thick piece about 1 1/2″ high – no issues. Then I switched to 4 mm and also no problems of course.
How large can holes be in the “wrong” (Z) dimension?
Again in that TV bracket I had holes of 4 mm and 6 mm in diameter in the z dimension. Do the rules about “bridges” apply? I have no idea, but they’re fine. Not smooth as glass, but sub-millimeter deviations from perfection. Definitely fine for passing screws through. maybe just a tad rougher in appearance than the surrounding surfaces. At some point as you scale up the radius, the top of a hole is a bridge, so failure has to occur, just thinking through this logically.
Do the belts and motors of the printer get loose after a few prints and after a year?
Not really. Mine still printed great after a year and light usage. I still can’t believe the quality that comes out in fact.
How uniformly does the print bed have to be leveled?
We all know you pull a paper through between nozzle and print bed and adjust until you meet resistance. What if one corner has more resistance than the rest? I would say it doesn’t matter. If you’ve ripping up the paper – that’s an issue, but the difference between a little resistance and more resistance should not be sweated. On my printer I assert it’s impossible to make the bed completely uniform. Also see the tip below about the print bed. I also recommend not to move the printer after leveling the print bed. I believe it will deform from even small movement. But I have printed six 50 gram jobs, one after the other, without re-leveling, which is great. The sixth job, however, totally failed. But see the next tip about watching the beginning of the print job.
Watch the beginning of the print job
I have lost prints twice. First time it was that the heated filament printed out a bit, but then the stuff on the print bed just started to be dragged around. Second time I printed a long, narrow piece. One end of it started to curl upwards like a water ski. I re-adjusted the print bed level no that side. Those things are going happen at the beginning of the print job if it happens at all. So watch the beginning of the printing for proper printing.
Are there differences in PLA?
Surprisingly, the answer seems to be definitely yes. The white PLA which came with printer seems to be much more fragile than the black stuff I bought (see link below). I’ve been told that the filament becomes brittle with exposure to air. With my white PLA it kept breaking off after a few days between print jobs, no matter what I did! The black stuff, by contrast, did not break off once! Not even when left in place for months!
Does PLA deform under tension or sheer forces?
See that C ring above? That was printed with the black stuff and used outside. It stretched noticeably over the course of the summer. perhaps a combination of the summer heat plus the tension. But whatever, the printed parts feel nice and rigid when first printed out, but they will permanently deform! Engineering plastics could probably address that, but I have no practical experience with them.
How to yank the finished print away off the print bed
You’ll break your fingernails trying to pry your printed masterpieces off the print bed. Of course I use blue painters tape over the print bed. I have settled on a technique where I use a needle nose pliers. Pull firmly while simultaneously pushing down with the other hand on the print bed. All my stuff, which is pretty dimensional, pops right off like that, and the tape is ready for another print – it is not ruined.
Thin strips are padded
With my setup, anyway, my thin vertical pieces are consistently coming out over the specified dimensions by about .5 mm. This overage can be important in a lot of projects. Similarly, holes are produced smaller than the specified dimensions, though I don’t know by how much, but seems to be in the range .5 – 1.0 mm. I know these things because I bought an inexpensive caliper!
How many parts of this type can you get from your spool of PLA?
Most (all?) of my projects involve fourth-grade level math, honestly. No algebra. Maybe a tiny hint of trigonometry. Anywya, Cura tells you how much PLA your printout will use. My TV bracket was around 50 grams. This is painfully obvious, but just to put it out there, do the math. If you have a 1 KG (= 1000 grams) spool of PLA and each thing you’re printing takes, e.g., 50 grams, you can print 1000 grams / (50 grams per piece) = 20 pieces.
Filament stops coming out in the middle of the printing – what to do?
I am currently suffering from this. I think my nozzle is too full of crud. I have no idea how to fix it (no time to research this).
I don’t enjoy tinkering with my finicky 3D printer. Is there a “3D printing as a Service” business?
I have been told there is not. People send ridiculously impossible things to print, expecting miracles. Perhaps someone will soon solve this issue (by qualifying all print jobs beforehand)? OK. There is a very commercial service. But it is way too expensive for hobbyist. Probably a minimum of $100. See the references for another suggestion.
Time-saving tip for leveling the print bed
My anet a8 prints great once I get it set up. But that setup – boy is it a pain. Leveling the print bed being the absolute worst. Because, if you follow their advice and adjust each corner, well, they don’t seem to stay and you end up reversing your direction on the screws of the print bed. Or you’ll get one corner and then the corner you had just done will be off.
But think about it. For these small jobs, it only has to be level at the center. So, the heck with it, just make sure when you drag a piece of paper with the nozzle at the center that it has a bit of resistance, and don’t stress about what happens at the four distant corners. You will maintain your sanity this way.
Conclusion I found the missing piece after printing this piece out, as luck would have it. BUT, then I found another place, right against the side of the house, that was never covered, but could have been. So I slapped my printed part there – it worked great!
A subsequent bolt hole cover project revealed that supports are nasty and basically impossible to remove. Yet the design was such that the thing worked anyways with a little superglue.
A plate to cover a hole in the mailbox post came next, and then a ring with a little slit for my bird feeder. Those two use an extrusion method.
You have to render your model or else export to STL does absolutely nothing, and also does not show an error, except in the console, which you may not be showing.
I learned quite a lot doing the curved TV bracket project. I shared my learnings.
References and related
3D-printing-as-a-service
If you are lucky enough to live in Oak Creek, Wisconsin, or really anywhere in Milwaukee county, you have it! And it’s really cheap – $.05/gram. https://oakcreeklibrary.org/3d-printer/
As for the rest of us, we have to encourage our local libraries and community colleges to get with the program. I think it’s coming, so make sure your interest is known.
This 3D printing service may be the most suitable for hobbyists: https://www.sculpteo.com/ . My modest wine bottle holder would cost $27 in their cheapest configuration (SLS plastic PA12). But at least their service looks really legit and gives you lots of options.
The program I use to generate my designs is Openscad. It’s free and still being actively developed. It’s great if you know a bit of scripting and a bit of geometry. https://openscad.org/
But there are a lot of other great 3D designs out there beyond just Thingiverse. This site introduces lots of these resources with example pictures from printed models.
