I’ve been trying to hone my programming skills a little and became fascinated with the idea of APIs. That is, sending a request to a remote server or database and receiving back a big stack of data that you can parse and do interesting things with.
Since I had a domain name that I’ve been sitting on for the last 7 years it seemed like a good time to try to implement an API call online and display the results.
I have lots to learn/add/improve still but if you visit:
entering a search term will request info from ebay’s database for your keywords and return the (most-watched, US only, links included ) results which are then arrayed onto the page.
The results are also affiliate-linked so if purchases are made I would then proceed to rake in mad pennies. If you’re in the market for a fleet of ebay yachts then please do visit the site.
I expected to find more on this topic on the world wide spiderweb, but since few have posted pics of this phenomenon I thought it would be good to do so. Maybe carpenters who work with cedar see it all the time but it was interesting to me.
In a nutshell, my wife asked if I would cut some some disks from a large red cedar branch that broke off a nearby tree. I used a miter saw (we call it a chop saw ’round these parts) to cut a bunch of disks –about 3″ diameter, 1/4″ thick drink coasters basically.
The cedar aroma was great and we left one wafer sitting around on the pantry shelf. A couple of days later I was back in the pantry searching for some type of food item that would require zero forethought or preparation time, and glancing at the cedar disk I noticed a frosty, sparkly something on its surface.
Looking closely, the red heartwood center of the wooden disk had grown very fine crystalline whiskers, some around 1 to 3mm long (yes I’ll switch to metric on you like that when the micron range becomes ponderable). The little clear needles seem to orient in various directions and extend out from the surface at different angles.
My quick and dirty “solubility test” consisted of a drop of water in one area and a drop of rubbing alcohol in another. The crystals were unaffected by the water and dissolved nearly instantly in the 70% isopropyl alcohol. Oh, and the flame from a lighter vaporizes them pretty instantly also.
From what I can find, the substance is likely crystallized libocedrol, a component of the aromatic oils found in the tree. The tree is Juniperus virginiana and I don’t know if any particular conditions like temperature, moisture content, etc. affect the crystal formation or if the tree just had a lot of the compound available to release. Nor have I researched what other trees may have it or if it’s common to see. I do know the internet needed a few more pictures of it so here are a few from my little USB microscope.
Comparison of digital microscope images from 20x to 230x on US$1 Benjamin. @20x magnification @40x magnification @50x magnification @100x magnification @200x … Continue reading →
Guitar Dan needed to test out his new amp so he threw together a few strings on a piece of wood, added a piezoelectric pickup, tuned it for about 30sec and then pointed the amp at me and turned the volume up:
We’re working on a CNC router for a customer who has an engraving process that they would like automated. Currently they engrave by hand and it’s very labor intensive…there is a better way! Here are some shots of the machine progressing:
I’ve been needing a low voltage, high current power supply lately for a couple of projects I’m working on (I can’t post about all my projects because some of them are proprietary for paying customers). I was looking for not just a few amps but hundreds of amps. This can be done with a transformer taken out of an old microwave with a little modification. Cayta found a heavy duty one at the thrift store for cheap so the fun could begin.
Word of warning: these are very dangerous and I’m not recommending that anyone try this. If so it is at your own risk and you should know that hundreds of amps is easily lethal.
I took apart the microwave (with the help of my godson) and pulled out the transformer. There are two coils of wire around an iron core, a primary coil and a secondary. By replacing the many wrappings of thin gauge wire with a single turn of heavy gauge wire, the higher voltage, lower current can be traded for a lower voltage with much higher current.
Transformer mid-hacksawing and dremeling
Transformer operation is explained by Faraday’s law of induction: basically when you have a varying electrical current (AC power) around a conductor it creates a varying magnetic field. A varying magnetic field with then induce an emf (electromotive force) or voltage in another coil that is in this field. It is remarkable that the other coil, the secondary, is not physically connected in any way to the primary, it is simply a single turn of wire, yet an amazing amount of current is “induced” in the wire by the magnetic field. This is something I “knew” but did not fully grasp until trying it myself (not that you should :).
Video of the device heating up a nail until its pulled apart:
and then fusing two nails:
So that was all fun and games but I took the nail melter apart because I needed to incorporate it into a power supply that outputs DC voltage. For this I added a bridge rectifier to convert from AC to DC, a capacitor for smoothing the output, and also incorporated a fuse in case things get out of hand. For example, these things get very hot when operating for any amount of time and can cause the wire windings to burn through their insulation and short out. This would usually just throw a breaker but I don’t want to create a fire situation. I’ll be using forced air to keep it cool and heavy duty heat sinking.
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