While building my CNC mini-mill, I purchased a 500W air-cooled spindle from eBay. It came with a power supply, which looked great and I (falsely) assumed it would work perfectly on my home-built mill.
Boy was I wrong! The mill worked great as long as the spindle was turned off. Whenever the spindle was on, there was a chance that the mill’s microcontroller would reset (bad), lock up (worse), or would suddenly enter an infinite loop (really really bad!) and an axis motor would begin moving in some direction until I noticed and stopped it.
After much work identifying and rectifying the causes, the power supply has finally been tamed. Here’s a guide for anyone having the same issues.
Astrophotography is a bit of a money pit. I recently delved into it with my 80-200 f/2.8L and a home-built tracking mount. It was so much fun that I decided to buy a telescope! So my entire budget went into an 80mm APO.
The problem was that a telescope alone is useless for star pics – some quality infrastructure is needed. This post is about my attempt to affordably build the following components:
High-precision Tracking Mount with an ASCOM-compliant driver
Guide camera and scope to help the tracking
Portable Power supply
Telescope Focusing motor with an ASCOM-compliant driver
Camera sliders are fun tools to use for making dynamic timelapse videos, and they come with some cool features. This is a clever little gadget that moves like a camera slider but folds much smaller. Eggtimers are also commonly used to make a similar effect. Some high-end gear can slide and rotate the camera at the same time for a particularly cool effect. But how do you guild one that one that could go up to 11?
The V2.1 update produced a working mount, but it unfortunately was not very user friendly. I made a few modifications to improve the setup and aiming time, as well as its ability to disassemble and stow in a modest-sized wood box for storage and transport.
V2.2 (codename: HoLi) is the mount’s final design, as I’m very happy with it and have moved on to building the V3.0. See the photo of Orion’s Nebula below taken using this mount, I’ve been happy with its performance using lenses as long as 300mm.
At the last minute, I purchased a sheet of Baader Planetarium solar film for the eclipse on Monday. With little time to spare, the film was taped to a cardboard box and slid over my telescope. Prayers were made that the wind wouldn’t blow the film off of the scope, and the next day I decided to build a proper holder for the expensive film – $100 CAD for an 8″ x 11″ sheet!
Wood burning is a popular hobby which can become quite expensive. A quality wood burning system consists of: 1. A pen or selection of pens and 2. A power supply (station). I decided to invest in a series of Razertip wood burning pens simply because they were available at a local Lee Valley Tools store (they also have a 1-year unconditional warranty – if I end up destroying a pen with a home-built supply then we will find out just how unconditional the warranty is). The pens are available for ~$30 each, which can become a significant investment if you want more than one or two. The stations run for $165 and up, which is the same price as six pens! So lets ditch the station.
2019-09-03: I’m considering manufacturing some sensor circuits and selling them for a reasonable price (probably ~$25 plus shipping for a pair). Eventually I will put a listing on tindie.com, but until then if you’re interested in building a ballistic chronograph and would like to buy a set of sensors, please contact me at email@example.com.
A ballistic chronograph is an instrument which measures the speed of very fast things (like bullets). I decided to build one which could be used for high-speed photography, such as glassware getting shot with an air-powered rifle (see my other post on this topic or my Flickr album). In order to take such a photo, you need to be able to trigger a flash at just the right moment, which will freeze all the juicy action.
There are numerous resources available which give very limited information on how to build such an instrument. Unfortunately all of the resources are incomplete or describe an instrument which only works for slower objects, such as paintballs or airsoft pellets. I designed and built this using the information available on the internet, my modest understanding of electronics, and many hours of trial-and-error. To somebody who has some knowledge of electronic components, this post can be used to build an instrument useful for measuring the speed of objects travelling up to 1,000 m/s (such as high-powered rifle bullets), and even photographing a projectile ‘interacting’ with other objects!