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Car Mirror Anti-Fog Film From Hell

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Wife bought a set of anti-fog film for her car and asked me to help her apply them to the side mirrors. Turned out to be a really bad idea.

Firstly, it is difficult to get good clean results. If you have ever tried to apply film-based screen protectors for your smartphones or tablets, you know what I mean. You invariably get smudges or bubbles under the film, and the result does not look quite as nice as what they show in the photos. Furthermore, you are doing this outdoors, where dust is floating everywhere and invariably get caught under the film.

Secondly, and that's the most annoying part about this product, these things stick like crazy! Once they are on, they are impossible to pry off the mirror! I got a fright when I realized the little piece of cardboard that was provided did not make the film budge. Tried a credit card, and that didn't work either. Tried hair dryer on high mode, nothing. At that point, I was extremely frustrated! What kind of product-from-hell was thi…

Current Meter based on ESP-12E and LTC4150

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I threw together a current meter based on the content posted here. It consists on essentially 3 components soldered on a perf board.



The 3 components are:
ESP-12ELTC-41500.96" OLED module SSD1306 (128x64) Here it is, hot-glued into a simple 3D-printed enclosure, and running:



The schematic is as follows: The meter is powered by the micro-USB port on the ESP-12E. I soldered header pins onto the IN and OUT terminals of the LTC-4150. The whole idea is that one could plug the source battery into the IN terminals, and plug the circuit to be tested into the OUT terminals, press the "Reset" (RST) button on the ESP-12E, and it will start measuring the average current draw of the circuit.
The current meter can be easily tested with a passive load like a 100ohm resister, which will simply display a constant current value (V/R). 
But it is really more useful for testing a variable load, like the ESPCLOCK, where running the current meter for a couple of cycles will give you a pretty …

Line adapter for Ozito Blade Trimmer

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This is an adapter for Ozito 18V battery trimmer (and possibly some Bosch trimmers as well) that uses a plastic blade for cutting.


It lets you insert a 2.4mm trimmer line (about 8cm long) and use that for cutting.


Simply cut a length of trimmer line and briefly heat up one end with a lighter so that a little bulb is formed.


Then insert the trimmer line into the adapter and slot that into the trimmer as per normal. Make sure the trimmer line is not so long that it touches the safety guard. If that is the case, simply trim off any excess with a cutter or scissors.


This part is best printed using PETG, which is a tougher and more flexible material. PLA is more rigid and breaks more easily. However, even with PETG, it will still break when it hits something really hard. Since this takes only 0.5m of material and 15 minutes to print, I will usually print a batch of nine at a time at very little cost. The blades that they sell do not break when it hits a hard object, but it will dislodge an…

3D Printed Universal Battery Capacity Tester

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Well, you don't really 3D print the entire battery tester. That would be neat though.


This is a actually a 3D-printed casing for the ZB206 battery capacity tester.


What you do print is an integrated battery holder (rubber-band-powered) that can hold an AAA, AA or 18650 battery for testing. So it is easy to pop in any of those batteries and begin testing its capacity immediately.


The ZB206 is mounted to the casing using 4 M3 x 6mm screws. There are 4 bolts that come with the board. I repurposed 2 of them as battery terminals, as shown in the photo.


You can find the OpenSCAD source file and STL file on Thingiverse

How to enable SMB1 on Windows 10

I have been bitten by this too many times, so note to self: If you are unable to connect to a network share on a new installation of Windows 10, and getting "Unspecified error 0x80004005" with a "net view \\REMOTESHARE" command, but "ping REMOTESHARE" works, then the issue is because the network share is using the ancient SMB1 protocol, and Microsoft has chosen to disable it by default on Windows 10 starting with the April 2018 Update.

There are 2 ways to re-enable SMB1:

1. GUI way
2. PowerShell way

Yes, I know SMB1 is deprecated for security reasons, but when you have working devices at home (eg. memory card on that Epson XP420 printer) that you want to get to over the network, you have very little choice!

Every time I hit this problem, I foolishly spend a few hours testing network connectivity and googling for the solution, which drives me crazy. Hopefully I remember this blog post the next time I inevitably hit the same problem again...

3D Printed Universal Tablet Grip/Stand

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I looked around for a gizmo that will let me hold my 10" tablet with one hand. These are my criteria:

1. Lightweight and portable

2. Easily detachable and re-attached

3. Effortless to hold

I didn't like any of the ones I found online, so I designed my own using OpenSCAD. It's a small handle with 2 holes for the index and middle fingers to slip though, and uses 3M Command Picture Hanging strips (medium size) to attach to the tablet.
You can hold the tablet securely with one hand in portrait or landscape position, or use it as a tablet stand. It is simple to detach and re-attach, and small enough to put int the pocket. It can also be adapted for both lefties and righties (or both, if you want to alternate between them).



One additional advantage is that the 3M strips can be removed from the back of the tablet without leaving a trace.

Print time is quite short and should not take more than an hour.

Find this project on Thingiverse.

Waterpik Flosser Leakage Repair

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A common complaint about the Waterpik Ultra Water Flosser is the leakage at the bottom of the handle where it connects with the flexible tubing, typically after warranty expiration. Look at the list of 1-star reviews of the product on Amazon, and you will see what I mean.

Fortunately, if you own some kind of gutter silicone sealant (I always have a tube of Selley's 1-hour Roof and Gutter Speed Seal Silicone lying around the house for small patch jobs), this is easy to fix.. Simply empty the water tank and make sure everything is dry, then mold a generous dab of sealant around the joint area. Then wait a few hours for the sealant to cure, and you are good to go.


In fact, I reckon anyone who owns this product should reinforce the joint with the sealant right from the get-go. Yeah, I wish they had adopted a more durable design in the first place, but having a few kids tugging at the thing every morning and evening, I am surprised it lasted that long (over a year).