Cannon has been coming along very well. I have spent the majority of my free moments–those not dedicated to studying for midterms or doing projects–getting Cannon together. Team Whyachi finally finished Coercion’s new 9.2oz, hardened S7 blade and Cannon’s 3.0oz titanium beater; I expect to have them here by Monday. The goal is to have Cannon in a place where I can plug in the beater and have a finished robot (but this is combat robotics, so that’s a very lofty goal indeed).
Since I last posted, I cut out the back and drilled the twenty holes that will hold Cannon together. I am using .375″ #6-19 button head plastite screws from McMaster-Carr, which are similar to the mind-bendingly strong ones that we used on Tough Nut last year. So far, everything seems to be holding up pretty well. I did the traditional “throw your frame down the stairs” test, and nothing broke. That means it will be super-strong in the arena, right?
The next steps in the build process will be to cut out and thread the ends of the weapon shaft, fashion a pulley for the weapon motor, drill and thread holes in the pulley I already have for the weapon, and then to get wiring. If I have time before Motorama, I will also harden Cannon’s S7 weapon shaft and Lolcat’s S7 weapon shaft. Lolcat’s bent at Bot Blast, so I do not have high hopes for its toughness against all the horizontal spinners that are registered for Motorama. However, the new motors I bought for it should provide a nice speed boost.
Here’s a front view of Cannon (note that I am waiting on shorter plastite screws from McMaster so not all the screws are in it yet):
It would look so much better with a weapon…
My father’s health has improved a lot and I have a three-day weekend: it’s high time I started getting the new version of Cannon built. I have spent the last few days machining away and making small changes to my drawings. With the exception of the first side rail (on which I carelessly used a 1/4″ end mill instead of the 1/8″ end mill I told my GCode generator I would use), everything has gone surprisingly smoothly. There have been no bumps in the road.
Just kidding, this is combat robotics — where the probability of fire is about equal to the probability of success. Things actually have gone relatively smoothly. The biggest issue I have had during my time standing in my machine shop was that the power went out while I was making the top. Luckily, I was able to finish cutting the piece out with an X-Acto knife. X-Acto knives always seem to save the day.
As of writing (I am taking a break from working), I have a very nice looking pile of parts. I just need to cut the back out and drill 20 holes before I can wire up Cannon and take it for a drive. Before any kind of spinning takes place, I will need to create some pulleys on my lathe and make a belt. It looks like everything will somehow get done before Motorama, which is a big relief.
Here are some pictures of the build process so far:
This pile of parts has about a month to becoming a functioning, radio-controlled killer.
The beginnings of a 3/8″-thick side rail for Cannon.
The mill putting finishing touches on one of Cannon’s rails.
A finished side rail. It needs to be cleaned up a little more and get mounting holes drilled in it, but it is more or less complete.
I’ll admit it — I am way behind of where I normally am robot-wise at this time of year. At this time last year, I was spending the better part of my weekends toiling over the mill trying to get Coercion done and troubleshooted. This year, much of the time I would have spent building robots has been dedicated to visiting my dad in the hospital over an hour away, as he has been very sick. Still, Motorama is about a month away and it will not wait for me. It’s time to get some robots built.
I have already designed Cannon and Coercion’s new blade (with some slight changes from the original post). Cannon’s blade and Coercion’s blade will be fabricated by Team Whyachi, since I am not overwhelmingly comfortable machining neither titanium nor S7. I don’t consider our mill’s CNC reliable enough to machine a hundred dollars worth of material at once. Besides, the S7 blade needs to be heat-treated to avoid another Bot Blast debacle (the blade bending 30 degrees).
Here’s what will need to happen over the course of the next month:
- I will need to receive Coercion’s blade and Cannon’s beater from TW.
- I will need to CNC mill Cannon’s body.
- I will need to create some blade hubs on the lathe.
- I will need to fashion and harden an S7 weapon shaft for Cannon.
- Lots of testing.
- Ordering a few new parts.
Overall, it should be manageable. There are a few three-day weekends coming up that I can completely dedicate to “botting it,” and there is still a month until Motorama. The race is on. Let’s hope it ends in a trophy…
The good news is that I converted all my SLDPRT drawings for Cannon’s sides into DXFs, then created GCode from the DXFs today.
I use GMail to transfer the files between my dad’s PC (which has the GCode generation software) and the mill-driving PC. I use Mach3 to drive the CNC.