I have two active 3D printers, each hooked up to their own Raspberry Pi 3 running Octoprint. I like to manage them from my iPhone when I’m about. I don’t want to expose my IoT devices to the Internet without some precautions.
My FIOS router on the left listens on port 80 and 443 and forwards that traffic to my Ubuntu Linux Server. On that server I run Apache2 with mod_proxy enabled.
I run ddclient to update a DNS name with my floating IP address. I use virtual hosts on the Ubuntu Linux Server to receive all external http/https requests. All http requests on port 80 get 301’ed to https on the same host.
First setup https on the virtual host as you normally do. Before trying to reverse proxy, have a default index.html file and make sure that works. I use Let’s Encrypt for the TLS certificate as it’s free and easy to setup.
Here’s reverse proxy configrution. 10.1.1.17 is the internal IP address of my first Octopi. Make sure the DNS name is working first before trying to test anything.
ProxyPass "/" "http://10.1.1.17/"
ProxyPassReverse "/" "http://10.1.1.17/"
# Options Indexes FollowSymLinks MultiViews
Header always set Strict-Transport-Security "max-age=31536000; includeSubDomains"
allow from all
AuthName "Wrapper Auth"
That <Location /> section on the bottom? That’s important. That’s the section that says “You need a password to access this URL” and protects the Octopi setup from passerby’s on the Internet.
What I tell you three times is true.
Do not expose any IoT devices on the Internet without encryption and passwords.
Do not expose any IoT devices on the Internet without encryption and passwords.
Do not expose any IoT devices on the Internet without encryption and passwords.
It’s just a bad idea. The wonderful Gina Häußge who writes and drives the Octoprint software knows this and has an excellent guest post on her blog about that access. This post is how I accomplished the Reverse Proxy method.
The password is created using the htpasswd command.
$ sudo su - www-data -s /bin/bash -c "htpasswd -c /var/www/external.htpasswd bob"
Re-type new password:
Adding password for user bob
I sudo as the www-data user so that the ownership of that file will be set as I want it. This creates a file with bob and his hashed password in it. The AuthUserFile directive will use that. If you have a valid user ID and password, you get in. If not you don’t get access.
The configuration gets copied for a new Pi. Just change the IP and ServerName and you can re-use this for other Octopi installations. By having an encrypted password protected access to your Octoprint setups, you can monitor and control your 3D printers from anywhere you have Internet access.
I’ve had my Monoprice Duplicator v2 for almost 2 years and it developed some problems.
The firmware lacked safety features I wanted. I could have (maybe) updated the code but I’m not sure how many features would fit. The board on it is an old Melzi clone and I would need to buy another board just to update that one.
The printer needed love and attention. I started getting layer shifts, the bed surface began to look like the surface of the Moon and prints started suffering from layer shift.
I really like 3D printers that auto-level (tramming) in some fashion. That’s my favorite feature on the Prusa Mk2s and it generally just works. Leveling this printer’s bed was a real challenge.
When I started looking the Ender 3 was the low end printer to get. It looks modifiable and a friend of mine likes his. He also purchased a Kossel delta printer and I was hooked.
Mini-Kossel vs Cartesian
Most 3D printers have a rectangular or square bed that moves forward and back for the Y-axis. The hot-end (the part that extrudes melted filament) moves left right on a rail for the X-axis and that whole rail moves up and down for the Z-axis.
What makes this printer different is that the bed does not move. The bed has a 240 mm diameter and is round surround by three columns. Movement is controlled by sliders on those columns moving up and down together. It’s very cool to see.
Since the bed does not move that makes what is being printed in place very stable. The head can move and I print infill at 100 mm/s. The perimeters of my 3D print are set at 50 mm/s but I can safely increase that to 80 mm/s without any worries and that’s fast.
ANYCUBIC Linear Plus Kossel
I don’t think the manufacturer produces this printer anymore. The support section is still there but it’s no longer listed as product. That’s cool; it cost me $218.40 with free shipping from Aliexpress.
The build took me about 90 minutes. The kit is already half-assembled and very straight forward. The end stops screws made me want to punch a kitten as the screws would not set all the way in. I will probably print new ones out of ABS and re-do them. Also not all of the screws or t-nuts were of the best quality and stripped easily. For what I paid I am not complaining.
I did a test leveling as detailed in Anycubic’s manual and looked for a kitten to punch. The process is just awful and resulted in a bad first layer.
Marlin 1.1.9 to the Rescue
I’m a big fan of opensource software and the process for leveling this printer with Marlin is detailed in this Youtube video. It was that video that convinced me to get this printer. Da Hai knows what he’s doing and has his configuration files available to download. My version is the larger size and I started to modify Marlin to adjust for my bigger version.
I promptly fell on my face too; I do not know what I’m doing in Marlin. Some searching and I found this excellent blog post which is a review of the same printer and how the author was able to upgrade to that version of firmware.
I tested, made a couple of minor changes such as the printer display name and adjust how auto-home works and poof! I updated the firmware.
Everything worked. I used the process from Da Hai’s video to measure the surface and printed away. It just worked. I’ve added Anycubic’s Ultrabase, re-leveled the print bed and just went.
There are some test prints that you do to make sure everything is working. I printed 3D Benchys, I printed a 6 gear bearing (it prints in place) and they printed fine. The measured bed leveling produced a perfect first layer.
Then I changed the PLA to some from Inland (I had been using the roll that shipped with the printer) and printed this print in place iris box. I have never been able to successfully print this one before no matter how I tuned my printers. You make some small cuts on the base and rotate the bottom from the top. I didn’t have much success in the past but the pieces always were locked together and would not move. The results were great. I had no problem with this one at all.
There are some artifacts in the print but it works. The printer is very precise.
Not for a First 3D Printer
This is my 3rd filament 3D printer. I’m comfortable with compiling the firmware, with the assembly, etc. but I do not recommend someone buying a Kossel printer unless they know what they’re doing.
The manufacturer’s documentation was very good. The printer was easy to assemble. Without the new firmware, without the very helpful posts and videos, I may have had a much harder time at it.
Since I do have some experience I’m having a good time playing with this latest toy.
I think I can call the multi-material upgrade of my Prusa Original i3 Mk2s a success. It took me about a day to put together and another day of tuning but I like the results and the prints look good.
Here's what you get with the upgrade kit.
A new E3D v6 with multi-material heat break
An additional daughter board to drive the extruder motors
All of the new plastic parts in ABS
Bondtech gears for the extruders
Spool holders for 4 rolls
All the fasteners needed
The instructions on Prusa's site are very good. I setup my laptop on the kitchen table, put the printer next to it and got to work. I took my time and spent 7 hours last Saturday just assembling it. A few quick tests and all was right in the world.
The Bowden tube setup is different and I need to get used to it. I had a clog on extruder 2 and had to unscrew the Bowden tube from the print nozzle to clear it out.
I did have to butcher my Lack table enclosure. I run my printer in the basement and that gets cold. Enclosing the printer guarantees that I'll get better prints.
Less S3D, more Slic3r PE
The one thing I am not thrilled with is the software. I use Simplify3D a lot because I generally get better results. S3D's supports are magical and just pop off. In the past I would use Slic3r PE only when I needed to.
S3D does not yet support the Prusa MMU. There is a single color profile that I found on the Internet and that works well. But for multi-color prints it's Slic3r PE or nothing. This isn't too bad for me because once the bed is level and the z height is adjusted (-0.867 mm on mine, I set the PINDA probe a little higher) I get good first layers.
The default printer profiles generally work. The only adjustment I make is to set the first layer speed to 20 mm/s. After that it's full speed ahead.
The Purge Block
If you look at the image with this post, you'll see that each multi-material print has a block next to it. When the printer changes filament the head moves to the block and prints a 60 mm by 10 mm layer. By the end of that the nozzle is primed and the color can be applied.
That layer of block either gets completely filled in or if there's not filament change a small infill is applied for the next layer. Here's a closer look at the 2 color Moai.
That print has 2 filaments on every layer. That purge block is solid at 60 mm x 10 mm x 60 mm. I don't really think that's wasteful as it keeps the results clean. I may play with those settings to reduce the size.
Here's the fun thing: if I printed 1 or I printed 10 on the same job then the purge block is still the same size. It has to be the same height as the print itself because the print nozzle cannot descend. That would risk hitting something else on the print bed. Next time I'll print more than one and lay it on it's back. That should reduce the purge block and get more use out of the filaments.
Where to Get Objects to Print?
You can make them yourself but Thingiverse is loaded with many good models. There's more than a few that my kids already want me to print. It will be a while before I really make my own.
In the meanwhile I have a printer that can do up to 4 different materials in one go. That's cool and I'm having fun with this hobby.
Sometimes my hobbies cross over into each other. This year I attended WordCamp US in Nashville and had an idea. Why not download and make a bow tie with a WordPress logo on it?
First I went to Thingiverse and I quickly found this one. I already had the WordPress logo from converting the SVG with Fusion 360 and I began to work on combining the two files.
About an hour later I swore profusely. I had a lot of problems. My PC was a little under powered. Fusion 360 can do amazing things and you can design a V8 engine with it including all the parts. My limited Fusion 360 skills were failing me.
All I wanted to do was take the logo, position it on the tie and export the results to a new STL file for printing. But I'm not really good at manipulating imported objects that way in a tool like that.
Tinkercad to the Rescue!
Autodesk makes Fusion 360 but they also have a 3D editor that lives on the web and runs in your browser called Tinkercad. I imported the two files, positioned the logo where I wanted it and exported it for printing.
It took me all of 5 minutes. The first pass had the logo a little too thin and it broke too easily. It was also upside down; I thought the clip on bow tie would work that way. Sometimes I make poor choices.
Just as before with my WordPress coin, I wanted the bow tie to be one color and the logo to be another. My working printer does this like so:
Print using one color filament till the 59th layer. I used a tool to figure that out.
Move the nozzle to the corner and the print away from the nozzle. The nozzle is 200° C and that will melt any plastic it is near.
Beep loudly. This is an important step as the 3D printer is in the basement.
I remove the old filament and insert the new color.
Log into Octopi via my iPhone's browser and tell the printer to resume.
That's it. The bow tie came out well and I printed a few more. Did I mention that I sometimes go overboard? I printed 9.
Opensource All of The Things
The bow tie I downloaded is licensed via Creative Commons – Attribution and Thingiverse provides an easy to print attribution card HTML. Which I could not incorporate into this post except as a graphic and a link.
The 3D printer community is mostly opensource and these were printed on a Prusa i3 clone. I used Simplify 3D to slice the file into gcode but there are some really good opensource slicers such as Cura and Slic3r. I've had some bad luck with Slic3r but I think I sorted that out now.
If you want to play with this modified bow tie then you can download it via Thingiverse. Or create an account in Tinkercad and play with it there. It's an easy thing to do and is lots of fun.
I had a broken dial. I also have a 3D printer, so rather than epoxy the heck out of the old one, I designed and printed a replacement. One finished 3D printed part was produced with just a few hours of work.
My pool has a salt cell that uses electrolysis to convert salt in the water into chlorine. You manually set the level from 10% to 100% generation but I usually leave it alone at it’s maximum setting.
That dial literally has one job and it broke. It was flush with the panel so rotating it meant scrolling the right exposed side. Built out of cheap injected plastic though it did last for 7 years.
In Fusion 360 I started with a stub to make sure I sized the knob holder correctly and ended up with a knurled dial that protrudes from the machine. My process isn’t very good and I learn through “what’s that feature do?” For example, the knurling was put on my making a sketch, extruding and cutting it out of the dial then creating a circular pattern out of that 120 times.
The effect came out great. My first pass has knurling that was too shallow (0.5 mm). Until I printed it out I couldn’t see that I had made a mistake. Once I saw it I went in the designs time line, deleted the sketch (which also deleted the pattern) and re-did it again. The new knurling rocks.
The last iteration was missing something. I put on the face a cutout to show that turning it clockwise means more, counter clockwise means less. The original dial had that printed on the face but my cutout is more prominent. It also meant I got to try something cool on my design.
I started with PLA but when I got what I wanted I printed it in ABS plastic. Here’s a photo of the iterations.
Yes, I could have fixed the old dial with some epoxy. That would have molded the broken part nicely. But it’s not often I get to use one of my toys in a real world way like this. 2 days of on/off fiddling got me the part I really wanted.
My daughter and a lot of her friends have begun to follow different K-pop bands. Putting aside that none of them understand Korean, they like the visuals and the beat of the music. And some of it is sung in English.
My daughter is crafty and I don’t just mean her attitude. Today she’s attending a birthday party and her friend is a big fan too. She took a small binder and using a word processor on the iMac made a 50+ sheet printed on both sides compendium of the bands they follow. Complete with the current band member bios.
BUT WAIT! THERE’S MORE!
She made stickers with the color laser printer and set them on the pages using Velcro. That way they can be re-positioned in different sections. The holes on each page and insert were done with a single hole punch.
She made folder inserts from stiff color paper and put printed material on and in them. She solicited her other friends to email her content and dolled that up too, formatting it so it printed and inserted correctly with the rest. She made a K-pop quiz complete with the answers in the back.
To make sure it’s a “living” book, she put all the document files and images on a USB drive that she’s included with the binder. That way the new owner can add or change the content as she sees fit.
I don’t know what to say. She draws and does crafts better than anyone I know.
Here’s a gallery of the book before it was given. I’m gobsmacked about all the attention to detail for this. She pulled all the images from online fan sites and formatted all the data.
My 3D printer only supports having one filament loaded at a time and that generally means the objects I print is one color. I wanted the WordPress logo (naturally) and two colors would be cool. I can print pieces in different plastics and assemble them but sometimes you want one piece. Good news! My printer’s open source firmware supports changing filaments before the print job is done. That let’s me start the base in one color but switch to another before the print is completed. Here’s how I did it.
In Fusion 360 I scaled the logo to 50 mm diameter. I then extruded the white portions in the logo to 3 mm. The circle outline and the space between the parts of the “W” were extruded to 1.5 mm. I exported that to an STL file and loaded it into Simplify 3D. This is where it gets clunky.
For slicing 3D prints into a format the printer can understand I use software named Simplify 3D. It’s not opensource (or cheap) but it’s very extendable and saves me a lot of time.
Simplify 3D supports scripts that use regular expressions to locate text in the generated G-Code output file and make substitutions. In the generated code it also comments each layer of the print so there’s a “layer 8” text where I want to insert printer commands to swap filaments.
Figuring that I needed to modify layer 8 was a pain. There’s probably a well documented way to do it but I sent my G-Code output file to Octopi. I loaded the file but did not actually print it yet.
OctoPi comes with a built in G-Code viewer. I moved the slider up until I found that layer 8 was where I wanted the change filament commands inserted.
I then deleted that file from the OctoPi, went back to Simplify 3D and in the process settings I went to Scripts -> Starting Script and added this to the “Additional terminal commands for post processing” field.
And generated and updated G-Code file with additional commands that I sent to Octopi. I loaded up a spool of blue filament and began printing. Midway through the print the extruder moved to the home position (but did not change it’s height) and waited for me to change the filament. Once I did that I loaded Octopi’s web page on my phone, logged in and clicked “Resume”.
The resulting prints came out well and I repeated the process with the white filament first. The bottom is one color and the top is another at just the right place.
This hardly took me anytime at all. It’s not a fauxgo, it’s a legitimate SVG (well, I hope it is) representation of the WordPress logo. The blue is a bit off but I can be forgiven for that. The PLA material is listed as “Egyptian Blue” and it’s the closest I had on hand.
There’s probably an easier way to get the layer accurately without using Octopi but it works. If I find an easier way then I’ll update this post.
What I really want to do is print the badges for the WordPress teams such as Support, Docs, training, etc. That’d be cool and I may do that this weekend.
This all came about because my brother got his 3D printer working in two colors on the same layer. His printer has two extruders and can print one color next to the other on the same layer. My printer does not do that but I’ll catch up. Competition is good. 😉
One of the reasons I like the Raspberry Pi is that it lets you take hardware and turn it into a dedicated purpose based appliance. Cheaply! And one of those uses is to make a retro game system. I've used the Raspberry Pi Zero before but I was hampered by the fact that it lacks network and Bluetooth access. To get that you need to purchase a USB hub, wifi dongle and if you want it an Bluetooth fob.
Here's how I did it with an 8Bitdo Bluetooth SNES style controller.
Download Retropie for the Zero onto another Pi Zero (non-wireless one, I have a few). I could not get the image to boot on the new device so I setup a hub with a wifi dongle and keyboard on an old version.
After the image reboots to resize the file system then F4 to get out of Emulationstation and on the command line run this command.
That will take a while to run and you will need to read part of the upgrade and press Q at a point. That annoys me as those commands should run unattended. Meh.
The purpose of this is to get the underlying Raspbian OS up-to-date.
When you’re done run sudo shutdown -h now and swap the old Pi Zero for the Pi Zero W. Unplug the wifi dongle, you don’t need it anymore. Boot up the Pi Zero W with the keyboard attached via the USB adapter.
Once it boots up press F4 to get back to the CLI and run these commands.
cd RetroPie-Setup sudo ./retropie_setup.sh
And select "U Update all installed packages" with your arrow keys. I don't know if that step is necessary but I do it out of habit. I like making sure I have the latest updates. That will take a long while too and reboot when it's finally done.
I already had the cables and power supply but I'm trying to be complete. Not counting the case it's ~$70 for this one player setup.
It's not a Raspberry Pi 3
The overall experience is good and if you limit your retrogames to the older 8bit systems then you'll like it. But the Pi Zero W doesn't have all the CPUs and RAM of the bigger Raspberry Pi 3. The good Neogeo games won't play well. Sometimes sound suffers due to CPU use. Lag is a thing.
But if you have the technical know how this beats the Nintendo Classic by a mile.
For Christmas one of my brothers purchased for my family (read that as “for Jan”) a Monoprice Maker Select v2 3D printer. This is a re-branded Wanhao Duplicator i3 V2.1 device. I had been looking at 3D printers for months (of course I was!) and Ed’s gift caused me to give him a big well deserved hug.
We used to hug all the time but in the past that would end up with one or both of us on the floor and our parents yelling “STOP FIGHTING!”
3D printers are good for easily fabricating small plastic objects from your computer. I’ve been using mine to create a few small items and print lots of free designs from Thingiverse.
An introduction! What are 3D printers?
They’re computer controlled precision hot glue guns but instead of a glue bead it sets a small line of melted material. And they print on a small area or bed.
A hot glue gun takes a solid glue blank and the metal tip of the gun warms up. This melts the end of the glue stick and you apply a bead of glue by squeezing the trigger. Melted glue is extruded out the nozzle and onto whatever you want to put glue on.
3D printers do exactly the same thing but it typically uses a thin plastic filament. The nozzle takes a 1.75mm filament, melts the end and extrudes it via a 0.4mm metal nozzle. The nozzle is attached to a pair of rods and a drive belt. The drive belt (the X axis) is moved by a stepper motor.
The height of the nozzle (the Z axis) is controlled by another pair of stepper motors. The nozzle outputs onto a horizontal heated bed which has a stepper motor to move forward and backwards (Y axis). That’s all you need to output melted filament to print one layer at a time.
The bed is heated because the extruded filament needs to stay put. That heat helps keep it in place and adhere to the bed. When the printer tries to put layer on top of layer, the old material has to be where it thinks it is. In the past people have used glue sticks, hair spray or blue painters tape to coat the bed and get their print to adhere. My printer’s heated bed came with a layer held on by adhesive called BuildTak.
3D printer material is a spool of filament and that comes in a variety of materials. My local Microcenter carries Inland filament in crazy quantities and I’ve stocked up already.
The easiest one to get started with is PLA or PolyLactic Acid, and yes I had to look that up. This material is based on sugar cane and when melted doesn’t produce toxic fumes such as ABS plastic does. PLA is easy to work with but it’s not as temperature resistant or durable as ABS. If you printed a cup holder and left it in your car in the summer then there’s a real possibility it will become deformed when it gets hot.
ABS is acrylonitrile butadiene styrene (and I looked that up too) and it’s the same material as many plastics in your household today. It’s a great material but the fumes are toxic and it’s prone to splitting or warping when printed. It’s temperature resistant once printed.
PETG (Polyethylene terephthalate) is an alternative to ABS. It’s durable and temperature resistant. I think it’s safe to use for applications such as food but it’s also finicky and I’ve not yet dialed in the settings to get really attractive prints in PETG yet.
There are other materials as well as a wood filament that you can sand and stain. I’m still a novice and I primarily print in PLA.
When you download or create files for your 3D printer they will most likely be STL files. 3D printers generally cannot process those. The files need to be sliced into layers and code for each layer.
My printer is an open source Prusa i3 clone and uses G-Code to accept commands that tell the printer what, where and how to extrude melted filament. The file format for 3D prints is typically STL format which the printer doesn’t handle. You need to use software that slices your model into G-Code.
There’s a few but a quick one is Cura. This is one of the open source software slicers that lets you set the set parameters for the print job. It’s free and easy to use. And after a couple of weeks I broke down and purchased Simplify 3D which is closed source and licensed to me for my one computer.
Non-open source code isn’t something that I prefer but this commercial software saves me a lot of time. Cura is very good but I print a lot and a half hour here and there adds up.
You can print via a USB cable to the printer but I don’t think that’s a good idea. Instead save your G-Code output to a microSD card and via the printer menu print from that card.
Printing from your PC could be risky. If your PC goes to sleep or reboots due to a scheduled update then you’ll waste a lot of plastic. Some print jobs take hours to complete.
I printed many things from and for my printer. I’ve also setup OctoPi, changed the printing bed and other things besides. But all that is for another post. This one is almost 1,000 words as it is. 😉
One of my recent hobbies (aside from breaking my WordPress site) is anything related to the Raspberry Pi. I use it as a network media player in my living room, USB computer on a stick and as a retrogaming console.
Nintendo recently released the NES Classic Edition which comes with 30 built in games. This holiday season it will be a big hit and it sold out almost as quickly as it was released. With a Raspberry Pi 3 running Retropie you can accomplish almost the same thing. It just takes a little geeky work and some parts.
Here’s the parts and links. I usually just drive out to Micro Center in Westbury and get it in person.
Borrow a USB keyboard from your PC or Mac so you can enter your wifi key. You won’t need it afterwards. I do all my Linux admin via ssh from my PC or Mac.
Your Raspberry Pi 3 running Retropie is a Linux server. It’s running a Debian based distribution called Raspbian. If you’ve spent time administering an Ubuntu LTS VPS then this will feel very similar if not downright identical.
The reason for getting your Retropie on the network is simple: once you do you will find a new Windows share at \\RETROPIE and you can deposit the NES ROMs you obtain in \\RETROPIE\roms\nes as easy as drag-n-drop. You’ll have to do some research where to get them yourself. They’re not hard to find.
When you do obtain NES ROMs make sure you keep them in individual ZIP archive files. Don’t extract them, just from them as is into your nes directory. Once you’ve gotten your roms onto your new system, press the “start” button on your controller and restart emulationstation.
So many emulators to use
Retropie supports many retro arcade systems. My favorite are MAME, SNES, NEO GEO and of course NES. I don’t play a lot of Atari 2600 games though I should. That’s one of the systems I had as a kid.
The emulators are easy to use. Generally you just drag the ROM zip file into it’s directory. Use \\RETROPIE\roms\nes and \\RETROPIE\roms\snes for the right one. You’ll see many more directories there but for now ignore them. You can explorer them later.
This is not a game system for everyone
If you are just looking for the classic NES games and can get your hands on one even with the small controller cables, then do so.
This illustrative YouTube video can explain the mindset of people who do this sort of thing.
You’ll either immediately understand where I’m coming from or you wont. That’s OK, some people just enjoy the nerdy aspects of things.
Using a Raspberry Pi 3 with Retropie is purely a geeky exercise. It works, it works well. It’s easy to maintain provided you are willing to learn the Zen of the Debian Based Linux Server™
Part of the appeal of the Raspberry Pi 3 is that it is a server with a quad core ARM CPU running at 1GHz. It has 1 GB of RAM built in. With a 32GB microSD card, case, and A/C adapter it’s a full on Linux server for less than $70.
Setting up a small PC with similiar stats will run you at least $200. The small size of the Raspberry Pi 3 shouldn’t take away from the fact that it is a Linux server. It has a default user ID and password. You should change that if you’re concerned.
Here’s an example of what I mean. Yesterday I did the following.
Ran cd Retropie-Setup then sudo ./retropie_setup.sh
Selected “Update all installed packages” and skipped the OS ones because I already did those.
Had coffee. See illustrative video above.
Ran sudo reboot to reboot box.
If you read that, stopped at step 2 and said “Are you kidding me?” then it’s alright. You’re OK. The NES Classic Edition is for you, it’s $60 and it is fire and forget. It does not have any network capabilities, it will never be updated. And there’s no legal question about using one either.
If you want to roll your own and don’t mind getting up to your neck in Geeky Nerdy things then maybe the Raspberry Pi 3 is for you.