The end of 2019’s first January cold snap brought out a whole lot of members and new visitors to our What’s This Laser Cutter Stuff All About? open house. Ylab’s Richard gave an extensive presentation on the materials you can use and the types of engraving you can make.
The highlight was some of his work with plastics and plexiglass, building up components in layers to make a complex manifold, and threading the plastic to hold screws and other fittings.
The meltdown happens when you bond together the plastic walls and layers to form a manifold. Instead of glue, you use the appropriate solvent for the plastic. The two surfaces melt a tiny bit and bond when pressed together. He’s tested the resulting piece to 60 PSI. He’s used the same techniques for water and air devices.
Best of all, participants in next week’s laser cutting class (sold out!) will learn to do it for themselves.
Ylab isn’t the only group haunting the DDO. We’re responsible for the strange sounds emanating from the basement – the things that go bump in the nights we are there. OK, more than bumping. Sparking, zapping, banging… On the upper floors we have the Royal Astromical Society of Canada Toronto Center (RASC), and the DDO Defenders (DDOD), delivering great astronomy programs for adults, families and kids. We often see them hosting hordes of Scouts and Girl Guides earning their astronomy badges.
Young was more than a telescope builder. He was Director of the DDO from 1935-1945, and, according to RASC’s bio, an astronomer’s astronomer. He had a big role in the design of the DDO’s flagship 74-inch telescope.
According the RASC bio, Young built his 19-inch telescope between 1926 and 1928. In the RASC Journal, Young says:
“It has been completed with the aid of a very modest workshop and occasional help for such work as could not be done on a lathe.”
But did Young use this lathe for his 19-inch design?
The Big Lathe was donated by Young to the DDO in 1934. Was it a new equipment for the DDO, or was it donated after using it to construct his telescope?
In our earlier post, we said the lathe was built in 1926. That’s according to a number on the cast into the iron base. Our lathe expert Miro said that’s probably a couple of years too early. The manufacturing process at the time involved casting the base, letting it sit around for a couple of years to ensure the metal was completely stabilised, and then completing the assembly. Better to look at the serial number, Miro says. The last two digits for a South Bend lathe indicate the production year. They read 28. As in 1928. It would then have to make it’s way from South Bend, Indiana to A.R. Williams, the Toronto machinery dealer, and to whoever purchased it.
Is that time frame too tight for completing Young’s telescope in 1928? Would a lathe have been used early or late in the process? Is the Big Lathe too big for what Young describes as a “very modest workshop”? Was Young being modest about his workshop? This Toronto Star archive photo shows the telescope in a location that is definitely not one of the DDO domes.
While ylab maker space is for adults, it doesn’t stop us from helping out with some stuff for kids. If you’ve come to one of our open houses, you’ve seen some of the things we’ve put together for Scout groups and camps. This fall we provided some assistance for a Rube Goldberg machine project.
The result – with all components built by the youth – is a monumentally complex system to pop a balloon. They used Meccano, Lego, Hot Wheels and other old toys; a steam engine; Arduino electronics… and the list goes on. Check out the video of the creation here on youtube. It filled a basement. No, it wasn’t our DDO basement.
Video submission for the contest was Dec 31, and they are eagerly awaiting completion of the judging some time in January.
Come out to the maker space, learn some new skills, and you can have a lot of fun spreading the knowledge by helping out with other groups. Might even be your own kid!
Jan 6 2019 update: 1926… or 1928? Learn more about the mystery here.
An important part of ylab’s activities in our home at the David Dunlap Observatory is ensuring we respect the historic nature of the facility. Sometimes this includes the great privilege and responsibility of maintaining some of the workshop equipment that we’ve been entrusted with – like the magnificent old workbench.
We’ve now taken the big South Bend metalwork lathe under our care. Markings indicate it was built in 1926. It has an 8 foot bed and 16 inch throw (largest diameter we can work with), which can be increased to 24 inches when taking advantage of a removable section of the bed.
So what on earth do we do with this beast?
Our good luck, as always (we’re in the DDO, right?), brings us a solution. Ylab member Miro, a professional engineer, has a wealth of experience with exactly this type of equipment.
Almost every piece of machine shop equipment of this vintage was put to work in the World War II production effort. Most of it was heavily worn during the process, if not completely scrapped when superseded by more modern tooling. Our lathe was used primarily – and apparently very lightly – for the maintenance of the DDO telescopes. Miro suspects it may be in better shape than any other one in the world.
We started with a thorough check-out.
First a general clean-up. We don’t know when it was last maintained… but the amount of crud we pulled out tells us it’s been a while. We made the arbitrary, executive decision that the crud is not historically significant and could be removed and disposed of. We trust nobody is upset by this. If this upsets you, let us know and we’ll send you some crud. Deadline for request: next garbage day.
If it’s supposed to move… WD 40 won’t do here. Moving parts need lubrication. We identified and bought the right grade of non-detergent oil. A careful end-to-end inspection revealed 31 separate lubrication points that include small holes, holes closed by screws, small caps, big caps, plugs and various surfaces. We found and refilled a historic oil can to do the job.
Missing and worn-out parts. We spotted some missing oil-hole cover screws. We made replacements. The carriage has metal caps that press felt pieces against the tracks to push metal bits out of the way as it slides back and forth. Two of the caps were missing – but we rummaged through the cabinets and found them. We put in new felt pieces and screws.
So how well does it work? The big test.
We manually moved all the parts, hand-turning everything. With fresh lubrication, Miro’s preliminary assessment was confirmed. Everything that should move was moving beautifully. Like new.
Time to turn on the power and see how this fat lady sings.
We tested with some 6-inch long, 1 inch diameter metal rods.
You can see the steps and the results below.
We used precision micrometers and vernier calipers to measure the progress and final results. We tested all the major gears, parts and settings. We cut and re-cut different diameters. We made screw threads on the end. And it’s unbelievable.
Almost 100 years old, and reliably delivering 1/1000 inch precision.
There are many more parts and options to test. Watch this space for more updates.
Ylab member Lucian has been running the Artificial Intelligence North meetups for the last couple of years at Markham Public Libraries’ Angus Glen branch. He’s had an incredible variety of quality speakers and topics – machine learning, neural networks and more. Click on the link to see for yourself.
The meetups have been managed from ylab’s meetup.com account. To allow us to do even more, we’re decided to bring it all to ylab’s home at the David Dunlap Observatory.
Hosting the events in our maker space will give us more flexibility on duration of events, as the library closes at 9 PM.
To prove it, we’re kicking off A.I. North’s fall season with our Python crash course for programmers. It will run from 7 PM to 10 PM on Thursday, September 20, 2018.
Python has become a dominant language for A.I. development and we want to get everyone interested through the basics. We’re hoping to do a lot more with it and some of the major A.I. toolkits in future sessions.
This is not a beginner’s programming course. We are targeting people who already know how to program, so we’ll be going quickly in to the features of the language. It’s a lot to do in 3 hours, but we’ve done it before and everyone got through it.
A dozen programmers came out to learn the language.
It’s a hands-on course, where everyone should come with the language pre-loaded on their laptop. We’ll be covering:
Basic structure for both procedural and object oriented usage of the language
Structure and use of libraries
The major data structures
Basic database access libraries – with a Postgres server to test!
Basic web access
It’s a lot to cover in three hours – but that’s the beauty of Python. If you already have some programming skills, you can move fast.
As always at ylab, we’ll be putting up the sample code and any slides on the web after the class.
We are charging a small fee for this event, and you can register here. Because, like, we pay rent for our space. We’ll have some cookies and beverages for the break. Spots are limited. Breaking news: we just listed the event, and it’s already half sold out before we finished writing this post! Our last class also sold out.
Big thanks from both A.I. North and ylab to Markham Public Libraries. They generously hosted events to help both groups get started, and we’ve co-operated on maker days and their excellent PechaKucha series. We look forward to working with them in the future.
Over the last couple of weeks, we’ve been performing surgery on the light sabres people made in our class several months ago.
All our light sabres can do single or multiple colours. Those multiple colours are way more impressive than the picture shows.
Our light sabres were designed by ylab member Richard. We have a custom circuit board with low-power ARM processor; multi-colour, 5V high-density LED strips; dual-channel sound generation with mini-SD card to load sounds; efficient power management; accelerometer to detect movement and collisions, and more.
Upgrading the firmware. Requires a PC and an Arduino board. Because it’s not a maker project if there isn’t an Arduino somewhere in the process.
Our class included basic soldering for connecting the LED strips; drilling and tapping screw and contact holes for the aluminum hilts; laser cutting the support strips; and all manner of required assembly work.
That first class was a true maker project, with a fair bit of experimentation and lots of learning.
As the first generation design, there were some problems, and we’ve had some repair and rework sessions. Our latest was on Monday August 20. Repairs included some soldering, taping, software updates and making a splint for a broken support piece. All light sabres brought in left in working condition.
A splice for a broken LED support. Custom made and carved out of Plexiglas on our laser cutter. Most appropriate for a light sabre.
With the oscilloscopes and other equipment we have on-site, we diagnosed a previously unknown power leak that would result in battery drain in 27 days. While that doesn’t sound bad, it’s still a bug. The design expectation was for a year on stand-by. We’re working on a fix. Fortunately, it’s just a software issue.
Testing, testing… with a nice DC power supply that shows current draw.
For those interested in making their own, it will still be a while before we fire up another class. We’re working on some re-design to make battery changing easier. But we hear you. We’re working on it.
We didn’t finish until late, which is a good thing. Because light sabres look even better in the dark.
Great to see many new faces at our amateur radio open house on Monday, June 25. In addition to the presentation and discussion around the various aspects of amateur radio, we had a great group of people from Toronto Mesh.
Directional antenna for mesh networks.
They are active in several areas of distributed mesh networks, and are putting a lot of effort into getting people educated. Some of them are playing a part in the our networks conference from July 13-18 that includes 2 days of seminars and 3 days of code sprints.
In addition to some classic ham radio decks, we showed off some really inexpensive technology like SDR (software-defined radio) USB sticks. Originally designed for terrestrial digital television, they can scan a full 6 MHz band, and are available with antenna and accessories for around $25.
Cheapo RTL-SDR USB wideband radio scanner. See the difference between CBC and Virgin Radio?