Sunday, October 8, 2023

Optimizing the vacuum adapter

Both of my Makita jigsaw and Makita sander have the same sized vacuum suction nozzles, and I use them quite a bit. The cheap Makita sander kicks up a lot of dust and short of buying another premium near-dustless sander for $500 (e.g. the 3M Xtract), I decided to just hook it up to my Festool Vacuum. I tried various universal adapters but none of them were to my likings, so I decided to custom design and 3D print my own. I went through several iterations and finalized on the smallest/lightest version. Below is my first version
This first version is a nice fitting test on the tubes. However, it's pretty long and clunky to use, so I designed another version where the vacuum length is reduced.
Picture to the left is the initial version, progressing to the right: I kept reducing the excess adapter size and at some point, I made the realization that Makita's smaller nozzle's outer diameter could simply fit inside the inner diameter of the Festool vacuum line:
Finally,
This is the final version, which is the lightest and easiest to work in tight spots due to the short length of the adapter:
In retrospect, it should have been pretty obvious to design the optimal adapter from the very beginning -- the outer diameter of the smaller nozzle fits inside the inner diameter of the vacuum tube. Hindsight!

Monday, April 4, 2022

Cub Scout Pack 415

Our boys are on their last year in the Cub Scout and "bridging" to the Boy Scouts. John our Den 3 Leader asked me to build a candle holder. After looking at some examples online, I built one, using all hand power tools (jigsaw, random orbit sander, drill, and trim-router). I made the whole thing out of a solid 2x8" block of wood. It was very fun to make, and I hope it will last for many years to come as I'm donating the candle holder to Pack 415. Below is a picture I downloaded online. It looks like a candle holder with 1/2" holes on top for 1/2" candles. However, since John already had a bunch of 7/8" candles, I decided to change the design such that the candles would go BEHIND the arrow:

Here is work in progress (I already jigsawed the 2x8" lumber):
Here's one way to use the holder (7/8" candle mode):
Here's another way to use the holder (1/2" candle mode. The pencils are simulated 1/2" candles):

Thursday, August 19, 2021

Building a 2021 PC

This blog is an attempt to jot down a whole week's worth of my time spent on researching/buying/building a new PC. If you're thinking of building your own PC, reading this may or may not save you some time/money.

It's been almost 10 years since I built a new PC. I switched exclusively to Apple hardware about a decade ago for several reasons. Being a dad, I didn't have much time to tinker with PCs and I needed something that "just works" at all cost. Fast forward 10 years, I now have a bit more time. Also, I'd like to show my kid the joy of having a powerful desktop by showing him some cool stuff like VR, MS Flight Simulator, etc. Besides, my 2017 Macbook Pro is starting to be annoyingly slow even for simple operations like Lightroom, Photoshop, and family video editing.

Instead of buying an expensive new Macbook Pro every few years, the intent of building my own PC is to know exactly what I'm buying so that I can expand it in a few years and make it last at least a decade. I don't want to buy a typical pre-built PC because they tend to come with cheap parts, RAM slots all pre-filled, lack motherboard documentations, and or comes with cheap motherboards that don't allow you to upgrade to newer generations of processors. Regarding processors, I decided to go with AMD's Ryzen series because of its superb performance/price ratio and that the AMD socket types (e.g. AM4 socket) is very very stable year after year. In contrast, Intel seems to come out with a new socket type every year, or something like that, which really turns me off because it precludes the possibility of upgrading newer processors with an older motherboard. No Intel, no messy LGAs. AMD all the way this time.

Below are the other parts I used. I've put links to Amazon.com and the prices at the time of writing (2021-08-19). Note that you may be able to get cheaper prices from eBay, new or old.
To start off, there are a few resources that are invaluable when picking out what parts you want. I used userbenchmark.com (click on Compare). It's a really great tool that shows you a wealth of information. I originally eyed the top of the line Ryzen 9 5950x 16 core 32 threads ($800), but eventually bought the Ryzen 7 5800x 8 core 16 threads449 $393 at the time of writing. 8 cores (16 threads) should be sufficient because anything more than 6 cores would (usually) not give you much boost in games, but 8 cores is sufficient to run 4k video editing + encoding for at least 5 years in the future. Besides, when Ryzen 5950x becomes really cheap eventually on eBay, there will be room to upgrade to 16 cores (32 threads).

There is a plethora of motherboards to choose from. My go-to choice is ASUS due to their superb history of compatibility and stability, plus it is the only vendor with 3 years of warranty. There are also great choices at lower prices from Gigabyte, AsRock, MSI, etc etc (all with 1 year warranty). However, this is an area where I'm willing to pay a bit more for name-brand so that I don't have to deal with finicky settings and unreliable motherboards (from bad past experiences). For AMD AM4 socket there are some chipsets you can go with. The latest and greatest one is X570 that has 100% PCIe v4 interfaces for multiple high end GPUs. But, they cost quite a bit more ($300-$500). So instead I got one grade lower, the B550 chipset, which is mostly PCIe v4 except one slot is v3-- this is perfectly fine since I only plan to add just 1 GPU for gaming. The one I got is Asus B550-F Motherboard ATX Wifi$210 $200 at the time of writing. The "rule of thumb" on how much to spend on motherboard is that a decent motherboard will cost about 1/2 the cost of the CPU (plus minus a little bit).

  • RAM: Corsair Vengeance LPX 2x32GB DDR4 3600 $400 at the time of writing. Yes it's possible to buy 4x16GB 3200 for a much much lower price, but in a few years when I upgrade, I would need to sell all of them on eBay (at almost nothing) to buy 4x32GB modules. So this is an area where I decided to spend a bit more on name brand and on fewer modules, for future expansion to 128GB.
  • HD: Western Digital SN850 1TB drive 7000MB/s M.2. I used userbenchmarks.com to look for specs. This is faster than Samsung 980 NVMe Pro M.2 for just a little bit more cost. I need as much IO as I can get for photo/video editing. Because this is name brand, it cost a bit more-- $200 at the time of writing.
  • CPU cooling: $65 $60 at the time of writing. Scythe Ninja 5 quiet silent cooling This is near silent as it runs at 800RPM and is less than 10dB. The down side is that it is HUGE so make sure it fits in your full sized ATX case. Check out pcpartpicker.com, a great site that helps you look for the right cooler.
  • Power: Corsair RM850 gold power $134 at the time of writing. There are some great web sites out there to calculate how much power you need. I used this one: http://www.powersupplycalculator.net/ -- I put in the above components + 2 GPUs (future expansion possibility) and multiplied the power by 1.5x to get below 850W, which is a safe margin. You can check out YouTube videos spend hours and hours on this topic.
  • GPU: This is a very personal choice. You can find plenty of used GPUs on eBay. Anything Nvidia GTX 1080 should be a decent choice. The RTX 3070+ are ridiculously expensive right now due to shortages, so I would wait to get new RTXs later.
  • Case: Corsair 110Q quiet case $100 at the time of writing. This is not a fancy see through case, but it is a quiet case with extra sound paddings inside. No pretty light, nothing. Function over form for me.
  • Bluray/DVD read/writer
  • OS: Windows 10 Home
  • Adobe Photoshop Elements and Premiere Elements photo and video editors
This whole thing comes out to be about $1700. I could have saved a couple hundred dollars by buying cheaper brands/parts but I wanted this machine to last at least 10 years and have room for expansion, so I got premium brands.
Out of curiosity, I checked how much the equivalent Mac Pro would cost, and this is what I got:
$6700 for an 8 core Xeon 48GB 1TB machine. I know this is an apple and orange comparison -- MacOS is a real UNIX that is really stable/reliable with really good support and same Adobe softwares (and probably better, since it's more stable). I guess I wouldn't mind buying the Mac Pro if I was somebody who owns a mansion and drives a McLaren :)

Wednesday, April 16, 2014

PamStroller - (How to conquer stairs)

It's very hard to imagine having a kid without having a stroller. One of the big complaints I have is having to move the stroller up and down the stairs. There's a big trade-off between having a huge SUV-like stroller with big wheels, and having a lightweight city/umbrella strollers with small wheels. In both cases, it is difficult to move up and down the stairs-- big strollers may have bigger wheels to climb stairs but are much heavier (20-30 lbs), while smaller strollers (8-20 pounds) have small wheels that are difficult to clear the stairs.

Last summer (2013) I started googling for strollers that can climb stairs more easily, but none of them are consumer ready and in production. So instead of waiting for one to come out, I decided to make one. After doing some research, tri-wheel base seems the most ideal configuration because of form factor, simplicity, and weight. Below illustrates how tri-wheel works:

The left most picture shows that intermittent but great amounts of effort is needed to either pull-up or move-down a stroller. The middle pictures shows that a super large wheel could gently spread the amount of effort needed (even though technically, the amount of "work" is the same), at the cost of weight and form factor. The last picture shows that with a tri-wheel, the amount of effort is similar to a huge wheel without as much compromise on weight and flexibility.

Here's a video of the prototype I made in action. I call it PamStroller:


PamStroller was prototyped by modifying the Chicco Lightweight Stroller. I also bought 2 extra wheel base from stroller parts store, and lastly the "Cosmos ® Pair of Replacement Stair Climbing Shopping Cart Wheels." Below are some pictures while making the prototype:
This is v1, mounted directly on the aluminum bar. It didn't work too well. The v2 version as shown on the video mounts to the plastic wheel mount, which allow me to easily exchange wheels (Chicco's original design to snap on/off wheels).

This is the original Cosmos wheels. First you take out the chrome pins.

Then, drill a whole in the center.

Add your own screws (about 4", I got these from Home Depot)

This is the extra wheel I bought, as I was about to destroy the permanent spoke, remove the rubber wheels, and replace it with Cosmos wheels.
It was a pretty fun project and took less than half a day! Is this a stroller you'd like to use? Would you like to see this readily available in stores? Are you interested in backing PamStroller on KickStarter? Please share and comment!

Wednesday, March 26, 2014

Bike Accident with a Toddler

I just looked at my blog history and find it interesting that the majority of my blogs are written months before I leave my job (i.e. most of them are written in 2009 Q2 & 2013 Q2). By inferring from historical data, I probably shouldn't be blogging now because I enjoy my time at work. However, I'm awake at 5am -- I keep having replay images of the bike accident.


 

I've made a lot of mistakes in my life, but this is an unforgettable mistakes that I made because it involves my 3 year old son Calvin. Calvin and I had a bike accident this weekend. His right side of the helmet cracked and he has some road rash on his right parts of the body (road rash pictures not show). I also have road rash on my lower legs and arms, and banged my right knee pretty badly. 


As we approached an intersection there were several cars in front of us. I decided to go around by swerving to the pedestrian lane (dumb!) and somehow, the front mountain bike tire got caught (on mere 1/2 inch height clearance) and *BAM* both of our heads went down first -- I can only remember hearing the sound of our helmets hitting concrete first -- and my son screaming and crying afterwards. It was the most awful thing I had experienced to date, and I caused it.

What amazed me was that after a few minutes of crying, he he said he wanted to go play in the park.



A few thoughts:
  • Always wear your helmet! There's a saying that falling from the bike is not a question of if, but when. Always wear your helmet!
  • If you must use systems similar to the WeeRide, iBert, rear seat, or anything that raises the center of gravity for the kid, DO NOT FALL because the head distance to ground is increased drastically.
  • I can no longer vouch for WeeRide. In fact I can't imagine using any system that raises a child's height, including the frontal iBert-style seats. BIG DISLIKE. I am switching to a trailer.
  • Don't underestimate a 1/2 inch height clearance even on a mountain bike. Always ride towards uneven surface by going perpendicular to it (see the Better green arrow above).
  • I just got a Burley Bee Bike Trailer. This is one of the best on Amazon (based on ratings and weight and quality). I highly recommend it. If you click on this picture and buy it, I'll get a few bucks from it too :)

Wednesday, July 24, 2013

Get a glimpse of the future (weight and height)

Ever wondered what your kid's projected adult weight and height is? Here's a really easy way to do it without having to dig up & look at AAP charts and/or cross reference with CDC data. Just to go http://www.wolframalpha.com/ and type in your query. For example, I typed a sample query below (this is not real data, they're just random number I picked), and search for "projected adult height":




WolframAlpha is an amazing computational knowledge engine in the world! If you enjoy using it, here are 32 other tricks you can do with it. If you like this blog, please share it with your friends and follow me for more goodies in the future!

Tuesday, July 23, 2013

Hacking for Parents

I saw this site with a bunch of simple hacks that will make parenting a lot easier. It's pretty neat, check out the link! http://iwastesomuchtime.com/on/?i=77931