3d Printing revisited

Roughly 5 years ago I bought a Monoprice Maker Select Mini ($200).  That broke in a fairly trivial way, I eventually got a full refund after some runaround...and spent $10 to fix it.  In the meantime I bought a Maker Select Plus for $399.  I had fun but when I decided to relocate them to our attic I never went through the process to calibrate them after the move and never printed with either of them again.  Eventually I sold them to a co-worker. 

Recently a couple of family members separately asked me about 3d printing which got me looking again.  I discovered the Bambu Labs A1 Mini--$200 for the basic printer, $350 with the AMS unit that allows multi-material printing.  Lots of good reviews, and it appeared to have substantially better features than either of my previous printers.  Rather than ordering, I went to Microcenter...where my wife talked me into the non-Mini version.  

The A1 Mini is a cantilevered printer--a single tower holds the printhead beam, while the A1 standard is a gantry system with two towers holding the beam.  This is typical for small printers-the single tower is cheaper, but it is harder to maintain accuracy over longer distances.   This was the case with my Monoprice printers as well, the Mini was cantilevered, the Plus was gantry.   The maximum print size of the A1 Mini is a 180 mm cube (the Monoprice Mini was about 120 mm) , while the Standard A1 is 250 mm cube, vs a 200x200x180 volume for the larger Monoprice printer.  

For the single color versions, prices are quite similar between the Monoprice and the equivalent Bambu--the minis were both $200, the full size were $400 for the Monoprice vs $379 for the Bambu.  The AMS module that lets you print with multiple filaments adds $150 to each of the Bambu printers with no comparable upgrade available for either Monoprice.  The AMS can be purchased separately. 

The AMS system is very worthwhile, letting you do 4 color prints, use different material for supports or automatically switch to a fresh roll when the first one runs out.  It isn't perfect--each change of material adds about a minute and wastes a bit of filament per layer, and it prints a purge tower (a rectangle of plastic) up to the height of your last color change.  This time and waste can be reduced at the risk of imperfect color changes.  The accuracy is extremely good--I printed some 2 color coasters that looked like a commercial product.  These work well with the limitations of the system--the color changes are all on the first 5 or so layers so the the extra time and filament is minimal.  This waste and time is per layer and doesn't increase with multiple similar objects.  If you stick with Bambu filament the AMS will automatically detect the type and color based on included RFID tags, this lets the slicer automatically set temperatures and speeds, and to pick the closest colors.  It is not particularly difficult to enter the settings for third party filaments, so you aren't locked into Bambu.  It is also trivial to move the RFID to a new spool--I did that when I re-spooled a tangled roll. 

Other differences between the Monoprice and the Bambu printers:

Automatic bed leveling--this is a major upgrade, measuring the bed height every inch or two and automatically compensating.  Monoprice was a manual system with the only adjustment being a screw in each corner that you adjusted so a piece of paper dragged slightly between the printhead and bed. 

Textured magnetic build plate vs plain fixed plate.  Prints are less likely to come loose during printing, but also far easier part removal.  No glue stick or tape needed for most filament.  You can either flex the plate to get stuff to come loose or let it cool naturally.  

Automatic tangle and end of filament detection--with Monoprice if the filament ran out or tangled the print job would be ruined.  The Bambu pauses the print and either changes the filament automatically or lets you fix the problem. 

Noise and vibration reduction--During setup the printer vibrates the various stepper motors to find the optimum setting to reduce both noise and vibration that could affect print quality.  I don't know how much difference this calibration makes, but the A1 is far quieter than the Monoprice printers and the noise isn't nearly as annoying.  The initial test is noisy, and my dog didn't like it at first...but it's relatively short vs hours of "singing". 

Color touchscreen interface--An improvement but minor. 

Built in camera.  Due to processor limitations the frame rate is a picture every few seconds, but that's enough to see if the printer needs attention.  It will take a picture from the same location at each layer to create a time lapse of the build.  This winds up being an enormous file for the short duration, and it requires that the print head move out of the way, which the manual says can create flaws in the print unless you also print a tower.  

Remote control--you can print from computer, Android or IOS.  There's even an app for Linux.  The Android and IOS versions are fairly limited, effectively requiring that someone has already set up a print profile and published to Makerworld.  This means 1 item at a time with little control of other settings.  It appears that the Linux version is  not identical to the Windows version.  The only missing feature I've run into is repairing an imperfect 3d scan requires Windows or a third party website.

Almost all of the current "best beginner 3d printer" recommendations are for one of the Bambu A1 printers, and this appears to be accurate.

Beeline Moto II initial review

The Beeline Moto II is an easily mountable smartwatch sized device that works with a companion app to show navigation on your motorcycle.  (It works on bicycles too, but the Beeline Velo is a cheaper version for pedal bikes)  Fairly expensive for the hardware...but I haven't found better functionality at a better price. The display shows a very simplified map--Your route with stubs to indicate intersections, the number of miles and an arrow for the direction of your next turn and a bar indicating how much of your trip is remaining.  It announces upcoming turns with a flashing light and a beep on both the Beeline and your phone.  The beep is a bit quiet compared to other sounds on the phone, and the beeps seem optimized for bicycling rather than motorcycling-The upcoming turn beep is at around 0.1 mile from the turn, barely enough warning for even fairly low motorcycle speeds.   I haven't used it enough to see how it deals with complicated intersections or interstate ramps.

The Beeline comes with a universal mount that attaches to your bars with O-rings as sturdy rubber bands.  It charges via USB C, and the screen is bright enough to see in full sun.  Control is by pushing the bezel in the obvious four spots, easy even with gloves.  There are options to show trip miles, speed (turns out my motorcycle speedometer is 4mph slow at 60mph) and speed limit signs--limits can be shown on the map display, speed and miles are on their own screens.  Speed limits are not reliable in my town, usually showing 25 even when the limit is 35.

The app gives the options of "fast" (minimum time) or "Fun" (more turns and fewer interstates-.   You can add waypoints.   A $5/month subscription gives the options of voice guidance and loop routes--tell it how far you want to go and any stops, it will plan from there. 

Before the Beeline I would use just the audio prompts of Google Map to navigate, but this had some issues.  When I choose something other than the default fastest route I'd often get a voice partway into the ride "I've found a faster route, if you want to stay on the one you chose, click the screen"...when my phone was in my pocket and my hands were gloved. I very much like the concept of just a beep to get your attention for a turn, I wish Google Maps had that option instead of choosing between "talk too much" or "don't alert me to turns at all".   The device requires the phone app, but apparently can import routes from some other apps.  The planning is reasonably sensible, but it doesn't know about temporary detours...and the minimalist map doesn't help in finding a route around a closed road.   I'd like less city streets in fun mode.    

As I said, the Beeline is fairly expensive for the hardware's capability.  Also expensive are the accessories.  There is a powered mount insert for $60...and it is incompatible with the stock mount.  That means an accessory mount of at least $25 more for the flat surface mount, or $40 for a bar or mirror mount.   It is possible to charge via USB while riding...but Beeline says that may cause damage that won't be covered by the warranty.  Battery life is pretty good, I'll just charge mine at home.  You can't turn the unit off before you end a ride, so that's 4 clicks and a hold.   It will go to sleep, and standby time appears to be decent.