Here is the 21st edition of our annual newsletter, the Lee Family 2025 Year In Review. All 21 editions dating back to 2005 are hosted on Dropbox, and blog entries from 2014 and beyond are accessible via the “Year In Review” tag. Also check out Victor’s YouTube channel to view home movies of many of the things we discuss in the newsletter.
I recently experienced my second Bambu Lab A1 3D printer malfunction in 13 months, and I started to question the durability of Bambu Lab 3D printers. Bambu Lab Support walked me through the troubleshooting process and sent me a free replacement Power Switch Assembly despite my 3D printer being just outside the 1-year warranty window. I received the part yesterday.
Although the replacement part did not come with an instruction booklet, the QR code on the box directed me to the A1 Power Switch Replacement Guide on the Bambu Lab Wiki. I followed the instructions line by line, and although some of the instructions had awkward wording that made it a little confusing to understand at first, the combination of the written instructions along with pictures made things pretty clear. The estimated time to replace the part was 20 minutes. I spent about twice that much time—I am not accustomed to repairing electronics, but I was able to get the job done. Here is the newly installed power switch assembly on the upper right, with the ground cable secured in place on the far left.
Here is where the cables from the power switch thread through a narrow trough to the compartment where the power supply is located. The wiki states, “Note: In the new version of the A1 power switch, we have optimized the cable layout by removing the intermediate ground wire connector to the AC board. Functional and safety tests have verified that this change does not affect the normal operation of the power switch or the overall system, while also reducing the number of connection points and improving the reliability and simplicity of the cable layout.” Hence, the neutral (N) and live (L) wires are connected, but the ground cable of the AC board (PE; protective earth) is intentionally omitted in the replacement power switch assembly.
Finally, I confirmed that there was power going to the 3D printer, as evidenced by the green “OK” indicator on the Bambu Lab Assistant.
After replacing the Power Switch Assembly, I was able to get 6 consecutive 3D prints without power loss. The first 5 prints were small jobs that completed in 20-40 minutes each. The 6th job was a 2.5-hour print, and given these results, I am confident that the printer power loss issue has been fixed.
Although the 3D printer malfunctions are a nuisance, I have to give credit to Bambu Lab for helping me address the problem. First of all, I appreciate the fact that Bambu Lab Support walked me through the appropriate troubleshooting steps. Many companies do not offer detailed troubleshooting and relegate that activity to the third party repair industry or would charge fees to diagnose and repair their products. Second, I appreciate the fact that Bambu Lab Support was able to identify the problem with speed and accuracy. I guess it’s not surprising that Bambu Lab knows their products better than ChatGPT. Third, I appreciate Bambu Lab Support’s flexibility in sending me a replacement part despite my printer falling outside of the 1-year warranty window—I feel that this represents unusually good customer service.
In summary, Bambu Lab lost some of my loyalty to their brand with the 2 malfunctions, but they gained it back with customer support. Thanks Bambu Lab!
On October 18, I mailed a package via USPS Ground Advantage to a friend. It contained a variety of 3D-printed objects such as personalized Halloween-themed coasters and glow in the dark skeleton keychains. It also included some Wallace and Gromit-themed toilet paper holders among other knick knacks. I sent the USPS tracking number and asked him to stay on the lookout for a package.
On October 20, the tracking information stated that it was out for delivery, so I notified my friend via email at 11:42 AM. He responded at 4:07 PM and said that although the tracking information was updated to “Delivered, Left with Individual” at 1:58 PM while he was at work, his daughter had been home at the time and didn’t receive the package. He wrote, “It could have been placed in our community mail box - the tracking messages often get mixed up.” At the time, I hadn’t heard of USPS tracking messages being wrong, but ironically I personally witnessed it happen a few weeks later, and I wrote about it here. Anyway, after he got home that evening, he searched the surroundings but could not find the package. After waiting a few days, the package still hadn’t shown up, so we concluded that the package was either delivered to the wrong address and/or stolen.
On October 27, my friend filed a report with his local post office. The postal worker referred the case to the local office supervisor. The next day, my friend wrote, “The supervisor called me back already and is contacting the specific mail carrier to figure out if the tracking message was accurate. She said sometimes they are not, or sometimes the mail carriers leave the key in the package box and not in the individual mailbox.”
My friend did not receive any additional communication, so I called his post office on November 7. I was told that in addition to the last status of “Delivered, Left with Individual” at 1:58 PM on October 20, he saw another tracking status in his internal system at 2:07 PM (9 minutes later) that it was scanned as “delivered at parcel locker” (a community mailbox) which the public tracking details do not state. In any case, the package could not have been both left with an individual and delivered to a parcel locker—one of those tracking statuses was wrong.
I learned 2 interesting things from ChatGPT about filing a claim for lost USPS packages. First, even if I did not buy insurance, certain shipping options such as USPS Ground Advantage (which is what I used) come with a limited amount of insurance, and I had entered $20 as the value of the package contents when I created the shipping label. Second, ChatGPT informed me that even for homemade items that are not accompanied by a receipt, I could estimate the cost of materials. I had nothing to lose by filing a claim, and at best I could possibly have my postage refunded and get reimbursed for the estimated cost of goods to make all of the 3D printed objects.
I submitted my electronic claim, along with a 3-page letter documenting the package contents. I used ChatGPT to both give me guidance on the structure of my letter, and I also asked it to critique my letter to optimize chances of a successful claim. I had taken photos of the 3D printed objects, so I included those in the letter, along with a screenshot from Amazon for the cost of a typical roll of filament, as I estimated that I used approximately the equivalent of 1 roll of filament to make all the 3D prints. In reality, I used portions of many different rolls of filament because the prints had multiple colors. In any case, I felt that my estimated value was fair.
Just a few minutes after submitting my electronic claim, I received an email stating that my claim was denied on the basis that (1) there was insufficient evidence of value and (2) proof of delivery.
It said that I could appeal the decision, so I did. Regarding insufficient evidence of value, the boilerplate language suggests that I did need some kind of receipt or statement of value, contrary to what ChatGPT told me about the ability to estimate the value of homemade goods. At the same time, I felt that the claim denial was automated because it happened within minutes of claim submission, and I doubted that a human actually read my 3-page letter. So I re-submitted my letter with the photos of the 3D prints and my reasons for estimating the cost of homemade goods at $20. Regarding proof of delivery, I felt that their delivery status was inaccurate because my friend’s daughter was home at the time of alleged delivery. I submitted the entire email exchange with my friend in which he stated that his daughter was home at the time of supposed delivery but did not receive the package. Not surprisingly, my appeal was rejected again on the basis that the package was delivered.
In conclusion, I was disappointed that my package was lost, or at least definitely not “Delivered, Left with Individual” as documented and that my claim was denied based on false evidence, but it doesn’t look like there is anything else I can do to get USPS to make things right or assume accountability for their error. I haven’t shipped any packages since then, but next time I send something important, I might consider using a different shipping company or sending via certified mail or something similar.
My friend purchased a gift for me from Amazon, and it was shipped via the United States Postal Service (USPS). My friend gave me the USPS tracking number so I could monitor its progress. On December 7, the status was changed to “Delivered, In/At Mailbox” at 4:52 PM.
I happened to check the tracking status around 5 PM and attempted to retrieve the package, but it was nowhere to be found. I considered several possibilities. I felt that the most likely scenario was that the package was delivered to the wrong address because I’ve seen that happen multiple time before—both with my packages being delivered to an adjacent building and with adjacent buildings’ packages delivered to me. Another possibility was that it could have been stolen, but given that only about 10 minutes had elapsed, and our apartment complex has generally not had a problem with package theft, I hoped that this was not the case. Finally, I considered the possibility that the tracking information was just wrong, but I hadn’t personally experienced that in the past, so I thought it was unlikely.
I notified my friend who sent the package to me, and he confirmed that he entered the correct shipping address. We decided that the most logical action was to wait a day or two and hope that if the package was delivered to the wrong address, then the recipient would deliver it to me. Also, Amazon says to wait 48 hours before contacting customer service when you have a missing package.
On December 8, my friend received an update in his Amazon app that the package was delivered at 9:56 AM.
In October 2024, I wrote about my Bambu Lab A1 3D printer heatbed temperature malfunction. Because the malfunction occurred within the 30-day replacement window, I was able to return the printer and have a replacement printer sent to me.
I have had a great experience with my replacement Bambu Lab A1 3D printer until November 2025 when I started witnessing that the printer would randomly lose all power. Sometimes it would happen during the pre-print routines (e.g., bed leveling, bed heating, filament purging), and sometimes it would happen in the middle of a print. Despite the main power switch remaining in the ON position, the printer would lose power, the fans would turn off, the screen would go blank and unresponsive, and the Bambu Studio slicer would lose communication with the printer. Initially this occurred infrequently, but it seemed to occur progressively more frequently over time to the point where most of my prints would fail due to unexpected power loss.
Because of the prior heatbed temperature malfunction in October 2024 and the current power loss malfunction in November 2025, I have started to question the durability of Bambu Lab 3D printers. Nevertheless, I bought another Bambu Lab A1 for three primary reasons. First, I enjoy participating in the Bambub Lab ecosystem where things just work (that is, until my printer breaks down). Second, I have meticulously set up air purifiers both inside and adjacent to my Bambu Lab A1 third party enclosure and didn’t want to re-configure my setup with a different printer’s form factor. I had considered upgrading to the Bambu Lab P2S, but that will have to wait. Third, Bambu Lab was in the midst of their Black Friday sale, and the A1 printer was on sale for $279 (normally $399).
Meanwhile, I asked ChatGPT to help me diagnose the problem, in hopes that maybe I could acquire parts to fix the older printer. After describing my scenario, ChatGPT concluded that there was an 80%+ likelihood that the power supply unit was responsible for the power loss. The other possibilities were a loose power connector (15%), a mainboard power regulator failure (5%), or a firmware or software issue (<1%). It encouraged me to contact Bambu Lab Support and stated that even though my printer was just past the 1-year warranty period, they might still help me out. I had previously written about the Bambu Lab Warranty, and at the time I had focused on the language related to returns, refunds, and replacement within a 30-day window. Looking more closely at the general warranty language dated November 18, 2025, it also says that there is a “2-year warranty for for consumers from the EU, Switzerland, Norway and Iceland” and a “1-year warranty for the rest of the world (any country not mentioned above).”
I submitted a support ticket to Bambu Lab, and they directed me to the Bambu Lab Wiki for “Printer Circuit Failure Troubleshooting - A1”. I confirmed that all indicator lights were in their normal status.
Based on questions from Bambu Lab Support, I also confirmed that the fuse was NOT blown, and the power switch had good contacts and no corrosion. Also, I measured the AC power input at terminals #4 (neutral wire) and #5 (live wire) of the power module, and the multimeter reading was 123.8 volts—a normal value in the United States.
Bambu Lab Support asked me if the main power indicator light would turn off when the machine is powered off, and I confirmed that it did. They also asked me to confirm that the 24V power module indicator light was a steady green light (normal state) when the machine is powered on, and I confirmed that it was steady green. They also asked me to verify that connections for terminals #1 through #5 on the power supply were properly inserted, and as far as I could tell, they were. Based on this information, they decided to send me a power switch assembly and noted that despite my printer exceeding the 1-year warranty period, “This component is a special free replacement.”
To me, this gesture from Bambu Lab went a long way toward mitigating my frustration with my 2nd A1 printer malfunction in 13 months. Also, ChatGPT was correct in encouraging me to contact Bambu Lab Support based on a history of them supporting printers past the warranty period. Although I still question the durability of Bambu Lab printers, I must admit that I have received very good support that has exceeded my expectations.
However, one main question remains. Although ChatGPT seemed at least 80% confident that the power supply unit was to blame, Bambu Lab Support sent me a free replacement part for a power switch assembly which ChatGPT suggested was a much less likely culprit. I updated ChatGPT with my recent interactions with Bambu Lab Support and asked if they perhaps wanted to first have me replace the power switch assembly because it was a less expensive part, and ChatGPT agreed with my assessment. It went on to say that it still felt that the power supply was still the most likely culprit and suggested that I replace the power switch assembly as instructed by Bambu Lab Support and see if that fixes my problem. If I still experience power loss after replacing the power switch assembly, then that makes the power supply unit the only remaining rational explanation. ChatGPT communicated to me that this is probably just the normal troubleshooting algorithm they go through. Bambu Lab Support has not commented on their protocol, but the ChatGPT response seems to make logical sense.
So now I anxiously await receipt of my free replacement power switch assembly. I hope it fixes the power loss issue but realistically expect that I may have to reopen the support ticket and ask for further assistance, with possible replacement of the power supply as a result. Stay tuned for what happens next!
On November 19, 2025, the Centers For Disease Control and Prevention (CDC) updated its Autism and Vaccines website to state the following (click image to enlarge):
I’d like to take this opportunity to debunk the first 2 bullets in the Key Points section, as the information is just plain wrong, based on a preponderance of what the scientific community knows today.
The first bullet states “The claim "vaccines do not cause autism" is not an evidence-based claim because studies have not ruled out the possibility that infant vaccines cause autism.” I’ve worked in a health services research capacity with a focus on evidence-based medicine for 16 years, and I can say that this statement is misguided on at least 2 levels. First, the claim that “vaccines do not cause autism” IS in fact an evidence-based claim. The original study that suggested a causal link between vaccines and autism has been debunked. It was formally retracted and its lead author was found to have engaged in serious research misconduct, including falsification of data and undisclosed conflicts of interest. See this story for more information. Since then, there have been no credible well-conducted studies that demonstrate a link between vaccines and autism. Evidence-based guidance is founded on the principle that the preponderance of credible evidence favors a certain conclusion. Any knowledgeable and unbiased researcher would assert that the claim that “vaccines do not cause autism” is in fact evidence-based because a credible link between vaccines and autism has never been established despite countless studies that examine the benefits and side effects of vaccines.
The second part of the first bullet that is misguided is the statement that “studies have not ruled out the possibility that infant vaccines cause autism.” This is just plain illogical and a confusing and possibly devious use of words, to which it is not logical to draw any meaningful conclusions. You see, studies cannot not designed to “rule out the possibility that infant vaccines cause autism” because no such association has ever been observed. If I stated that “studies have not ruled out the possibility that pigs can fly” then it would be illogical to conclude the opposite argument that MAYBE pigs could fly, unless there was any credible observation that they could in fact fly. I believe that such a meaningless statement could only be made by someone who either has ulterior motives or beliefs that are not supported by science, or they are possibly made under duress.
Moving on to the second bullet point that “Studies supporting a link have been ignored by health authorities” is also misguided. The reason that health authorities ignore studies supporting a link between vaccines and autism is because there have been no credible scientific studies that support such a link. If I said that “studies supporting the possibility that pigs can fly have been ignored by the general public” then a rational person would say that those studies should be rightfully ignored because pigs have NEVER been witnessed to fly, based on credible evidence. So to imply that health authorities are sweeping an issue under the rug requires that there be a credible and rational reason to pay attention to the issue. In this case, there is no reason for health authorities to waste time on this issue. In my opinion, the only reasons we are even discussing it is because the general public does not have a sufficient understanding of the scientific process, and conspiracy theories arise from this lack of understanding.
Regarding the third bullet that “HHS has launched a comprehensive assessment of the causes of autism, including investigations on plausible biologic mechanisms and potential causal links,” I am supportive of such actions and can only hope that this research will be carried out responsibly and in accordance with the scientific method. I also assume that such a “comprehensive assessment” would result in data that are in agreement with the preponderance of previously established scientific information, and if so, then I hope that rational individuals would challenge their prior unsupported beliefs about a link between vaccines and autism. However, if HHS’ “comprehensive assessment” does not involve original credible research and they instead cherry-pick data from poorly conducted studies, then it will be obvious that HHS/CDC is driving a political agenda (as if it was not already clear). On the other hand, if there is novel credible research that is performed according to the scientific method that does in fact establish a link between vaccines and autism, then I will be eager to read that research, modify my perspective on this topic accordingly, and encourage additional studies to further corroborate such novel evidence.
In summary, the claims made by CDC are wrong and misguided based on a preponderance of the best available scientific information. At best, the claims represent a misunderstanding of science and evidence-based medicine. At worst, this is an example of misinformation by what was previously a well-respected federal agency. For additional reading on this topic, see the NPR article “The CDC revives debunked 'link' between childhood vaccines and autism” on 11/20/2025 and the Los Angeles County Department of Public Health’s “Statement on Updates to CDC Website on Vaccines and Autism” on 11/21/2025.
Yesterday I received an email from YouTube with my 2025 year in review. It contained many statistics such as the fact that I started my channel on January 4, 2007, which means I’ve been a YouTube creator for 6,912 days. They also provided me with my top video of the year:
I knew intuitively that most of my subscribers would be from the United States, but little did I know that I have subscribers elsewhere:
And finally, I was given some statistics on the age groups and days of the week when my audience views my videos:
If you want to see the videos on my YouTube channel, search for @DigitalDaddyLA or just visit https://www.youtube.com/@DigitalDaddyLA/videos.
