Bambu Lab A1 Heatbed Temperature Malfunction

I’ve been enjoying my Bambu Lab A1 3D printer. Bambu Lab has done a great job of improving usability of the entire 3D printing process--this includes its MakerWorld model repository, its dedicated Bambu Studio slicer, its calibrated filaments, the Bambu Handy mobile app, and of course the speedy 3D printer itself. Everything just works the way a 3D printer SHOULD work. That is, until it doesn’t.

A couple weeks ago I started to see “Heatbed temperature malfunction” error messages as pictured above. Initially these errors would appear after successful completion of 1 print job and upon the initiation of the next print job without turning the printer off. After pressing the “Confirm” button in Bambu Studio or dismissing the error message on the touchscreen, I would see that the newly initiated print job was suspended in a paused state. After pressing the resume button on the touchscreen, the heatbed would proceed to warm up to the specified temperature (usually 65 Celsius), and a successful print would ensue. I was hoping that this error message was due to a firmware or Bambu Studio software glitch, as I had recently updated both.

However, after several days of encountering intermittent “Heatbed temperature malfunction” error messages in between print jobs, I experienced this error message in the middle of an 8-hour print job, and upon dismissing the error message and resuming the print, the heatbed remained at room temperature. I was concerned about the print falling off the build plate (because warmer temperatures help the printed materials stick to the build plate) but fortunately I had excellent bed adhesion, and to my pleasant surprise, the print successfully completed anyway.

Upon reporting this issue to Bambu Lab Support, I was asked to troubleshoot the heatbed issue by following these instructions on the Bambu Lab Wiki. After purchasing a multimeter and asking ChatGPT how to use one, I was able to confirm that the resistance measurements of the temperature sensor connector and the heatbed power supply connector were both abnormal. According to the wiki, “replacing the heatbed assembly is necessary if both resistance values are abnormal.” So I thought Bambu Lab was going to ship me a new heatbed assembly and I’d have to follow these instructions to replace the heatbed.

Instead, Bambu Lab Support offered to continue troubleshooting the issue by first sending me a new AC board, which contradicts the recommendation from the wiki, or to return and replace the printer because I was (barely) within the 30-day time window after receipt of the 3D printer. Since I am not knowledgeable about electronics, I decided to return and replace the 3D printer and had to follow these instructions to pack my printer. Because I bought the A1 combo which included the AMS Lite unit, I had to return the whole set—this seemed wasteful because the AMS Lite unit was working fine. Anyway, the photos and videos were helpful, but if there was one thing I learned from the experience of packing the printer and accessories, it is that it was extremely important to have saved the original box and all of its packing materials, including the plastic bags and protective foam pads and cardboard inserts.

Bambu Lab provided a UPS shipping label and informed me that “the return process can take around 2-3 weeks, depending on the shipping conditions” and “the replacement will be arranged within 7 business days after the warehouse receives and inspects the package.”

Overall I wish it was a little easier to troubleshoot 3D printer malfunctions, but the Bambu Lab Wiki made the process as simple as it could possibly be. Perhaps a better approach to support average everyday mainstream users would be to have dedicated Bambu Lab service centers, but of course there would have to be a business model to make that happen. Because I purchased my 3D printer from the online store, I had no choice but to work through the online support process. Had I purchased the printer from an authorized reseller, I assume that I could have returned and replaced the printer in the physical store, and I wonder if I could have avoided all the troubleshooting and packing steps. Unfortunately the nearest reseller is about 50 miles away from where I live, but if you live near a reseller and are thinking of buying a Bambu Lab 3D printer, that option may make more sense.

Anyway, I hope my replacement A1 Combo will arrive soon and that there will be no malfunctions with my replacement device.

Southern California 511

When driving locally in southern California, my main concern is about traffic conditions, so I use a variety of GPS applications including Waze, Apple Maps, and others. However, when planning trips of longer distances or through mountainous areas, it can be helpful to have real-time information about road closures and other hazards to avoid unfortunate situations like this.

For decades, I’ve relied on Caltrans for highway information, and it can be accessed via phone by dialing 511. I just learned that there are now dedicated websites for different regions of California, including Bay Area, Inland Empire, Kern, Sacramento, San Diego, Santa Cruz, and Southern California (http://SoCal511.com/ which redirects to https://go511.com/).

According to the website, “Southern California 511 is a free traveler information service that provides live traffic reports, transit planning, commuter service information, motorist aid, or FasTrak information in the Southern California area through a toll-free phone number, website, and mobile application. Call 511, visit Go511.com, or download the Go511 mobile app to retrieve all the information for your traveling needs. 511 will help improve your commute and keep you informed before leaving the house and while on the go.” Here is an example of the current alerts if we were to drive from Los Angeles to Las Vegas:

In addition to maps for personal vehicles, Southern California 511 also provides trip planning information for public transit and bicycling. Finally, check out the Southern California 511 feed on X. Their handle is @Go511. Safe travels!

Protect Your Identity

Last month, news broke that hackers stole and sold personal records of 2.9 billion people. The records were stolen from a company called National Public Data which provides services to staffing agencies, employers, private investigators, and other organizations who perform background checks. This apparently places a vast majority of people who live in the United States, Canada, and United Kingdom at greater risk for fraud and identity theft. Also, while this was perhaps the largest data breach of personal records, there are countless other data breaches that have likely resulted in your personal data being released to the dark web. To protect yourself, here’s what most experts recommend.

1. Set up accounts at all 3 major credit bureaus: Equifax, Experian, and TransUnion. While all 3 credit bureaus offer security products and services, setting up an account is free. Remember to safely store your username and password information (that is perhaps the topic of another blog post).

2. Check your credit report from all 3 major credit bureaus. If you’re not accustomed to doing this, the key things to look for are the accuracy of your contact information, revolving lines of credit, and inquiries. If a criminal has attempted to open up credit cards, take out a loan, or change your home address, you should immediately spot those. In the unfortunate event that someone has tried to steal your identity, follow the steps at IdentityTheft.gov.

3. Place a fraud alert on all 3 major credit bureaus. This will make it harder for a criminal to obtain credit in your name because businesses must verify your identity before issuing credit in your name—note that this is why it is important to verify your contact information in item 2 above. All 3 credit bureaus offer fraud alerts for free, and it lasts a year, after which you can renew it (also free). If you were a victim of identity theft and have a police report, you can place an extended fraud alert which will last for 7 years.

4. Place a credit freeze on all 3 major credit bureaus. This provides even greater security than a fraud alert because when your credit is frozen, nobody will be able to access your credit report or open a new credit account until your account with the specific credit reporting bureau is unfrozen (or “thawed”). Like all the other steps above, credit freezes are also free, and they remain in place until you thaw your account. Note that when you thaw your account, you do not necessarily need to thaw all 3 credit bureaus. Let’s say you want to buy a car, and the dealer wants to check your credit before issuing you a loan—if you know which credit bureau they use, you can temporarily thaw that one and then freeze it again after you complete your transaction. Also visit this FTC site to read about differences between fraud alerts and credit freezes.

5. Optionally place a credit lock on all 3 major credit bureaus. I say this is optional becuase the differences between freezing and locking your credit are minor. According to NerdWallet, freezing your credit usually occur within 1 business day and thawing occurs within 1 hour if done online, while locking and unlocking occur instantaneously. Although Equifax offers locking/unlocking for free, Experian and TransUnion charge a fee for this service. If you value the convenience of instant locking/unlocking and are willing to pay the fees (if any), then this may be a desirable option. Otherwise with just a little bit of planning, you can skip this step and achieve all 4 prior steps for free.

One last word on Equifax credit locks. As I mentioned above, Equifax offers credit locks for free, and this is done through its Lock & Alert service. Just note that if you sign up for Lock & Alert, you will need to register with another account that is separate from your “regular” Equifax account where you check your credit report, place fraud alerts, and freeze/thaw your account. I don’t know why they don’t just combine them together, but just note when storing your account information that these are 2 separate accounts. If you’re an Apple user like me and use iCloud to store your passwords, note that there seems to be a limitation where iCloud tries to be helpful by merging these 2 accounts because they have similar domain names. Do NOT overwrite your “regular” Equifax username/password with your Equifax Lock & Alert username/password or you will lose one of them. Hopefully Apple will come up with a solution for this scenario soon.

Wildfire Maps

In California, the fire season generally starts in June or July and runs through October or November. Currently there are many fires burning in California and in many other parts of the United States (and all over the world for that matter). If you’d like to visualize wildfires on a map, you have several options.

CAL FIRE displays current wildfire information in the state of California. There are options to display recent perimeters, active air assets, and other options.

Google Maps can display wildfire information if you click on Layers > More > Wildfires.

MSN Weather Map also has a map with a dedicated Fire Information layer.

All screenshots were taken within the last hour, so you can compare and contrast the available information and visual presentation. Be safe out there!

Bambu Lab A1 Timelapse Videos

I recorded a timelapse video while printing an object with my Bambu Lab A1. While printing from the micro SD card, I noticed that after selecting my print file, there was a “Timelapse” button on the touch screen that could be toggled on/off prior to starting a print. I turned it on and started the print. A timelapse video was then saved to the micro SD card which I transferred to my computer upon completion.

I learned afterward about the Bambu Studio slicer options for timelapse recordings. You can choose between Traditional model and Smooth mode. Because filament can leak while the print head moves out of the way for the camera to take a snapshot, this can result in imperfections in your print. In Smooth mode, a prime tower is added to your print so that the excess filament can be ejected into the prime tower, resulting in preservation of print quality. So basically you’ll need to choose between compromising print quality or wasting filament in your purge tower. Refer to the Bambu Lab Wiki for more information about Timelapse Functionality.

The timelapse video is in 1536x1080 resolution and is saved to the micro SD card is a .avi file that is encoded with a MJPG codec which is basically a video that is composed of a series of JPG images all compressed into 1 video. The problem I encountered is that many macOS applications cannot decode this format. QuickTime chokes entirely, while VLC displays a “Broken or missing index” error but then eventually allows me to view the video. Final Cut Pro is unable to import the .avi file at all. Fortunately, HandBrake is an open source video transcoder that easily converts the .avi file to .mp4 which is more or less universally compatible with everything nowadays.

Besides the filament leakage issue that I discussed above, another disadvantage of recording timelapse videos is that it adds several seconds of print time to every layer. I won’t be regularly recording timelapse videos of my 3D prints due to the tradeoffs, but it’s great to know that the Bambu Lab A1 has this capability.

Daddy’s New Toy (Bambu Lab A1)

In May 2023, I purchased my first 3D printer, a Creality Ender-3 V2 Neo. For the past 16 months, I have enjoyed learning about 3D printing, model design, model slicing techniques, and getting the end result of having a physical object in my hands. My 3D prints were often for entertainment, although many of them were also gifts or even serving a functional purpose (e.g., repairing and/or upgrading household items). For this, my Ender-3 V2 Neo served me well. On several occasions I’ve had to replace various parts such as 2 hot end fans on separate occasions (which unfortunately required me to disassemble and reassemble all the wires connected to the main circuit board), nozzles, and PTFE tube pneumatic couplers. I also upgraded my heat sink to lessen the chance of filament clogging. Last month I started to experience a higher rate of print failures, particularly on more complex objects. I noticed that my nozzle temperature was no longer holding steady but rather bouncing above and below my set temperature by 1 degree Celsius. To me, that was a harbinger of dreaded additional repairs. Had it not been for the high rate of maintenance work, I probably would have kept my Ender-3 V2 Neo a lot longer.

Earlier this month, I upgraded to a Bambu Lab A1 3D Printer. In addition to much faster print speeds and a larger build plate, the Bambu lab A1 has the ability to print in multiple colors using its AMS or AMS Lite systems. Additionally, the Bambu Lab philosophy seems to be aimed at making 3D printers easier to use and less prone to failure. For example, the A1 is programmed to perform automatic bed leveling, vibration detection, and filament flow calibration by default (most of these can be disabled) prior to each print. The Bambu Studio slicer is similar to Cura and other open source slicers, although there are some nice features that I’ve appreciated seeing in Bambu Studio such as the ability to define filament-specific profiles where nozzle and bed temperatures can be defined for different filaments, rather than defining them per model in Cura. Bambu Studio is also integrated with Maker World which is an online repository of 3D models that also allows users to upload Bambu Studio print profiles—this lets Bambu Lab 3D printer owners to print directly from Maker World to their 3D printer.

I’ve done some test prints just to get familiar with the hardware and software, and I’m impressed so far. In the near future, I will be experimenting with multi-color prints through my AMS Lite system, timelapse videos, and other new features.

Factors Affecting 3D Printed Object Strength

Steven from 3D Printer Academy released a video to his YouTube channel in early 2024 to discuss how wall line counts and infill contribute to the strength of 3D prints. The full video is here:



Bonus: the precursor to this video is here.

Strength tests were performed on 3D printed beams with grid infill and showed some interesting results. All of the following images are screenshots from the video above.

With increasing wall line count…

• Strength increases linearly
• Strength to weight ratio increases but with diminishing returns

With increasing infill percentage…

• Strength increases
• Strength to weight ratio decreases

The optimal strength/weight ratio is around 20% infill and 3 walls.

Regarding the relative strength/weight ratio of infill types, lightning infill had the highest value, and the author believes that due to the nature of lightning infill, the object is very light, so most of the strength may be coming from the walls. I agree and would also add that because lightning infill is not uniformly distributed throughout the object, the findings related to this infill type should be interpreted in that context. The infill types with the next highest strength/weight ratios were gyroid and 3D honeycomb.

Note that if you use Cura as your slicer, it does not currently come with 3D honeycomb or honeycomb infill. You can get honeycomb infill for Cura, but if you want 3D honeycomb infill, you will need to use another slicer.

Personally I like cubic and gyroid because they are “airtight” in all 3 axes and presumably could withstand forces equally in all directions. Does this information influence how you will slice your next 3D model?