A knife for father’s day

My nephew loves his dad.

I said I would help my nephew to make a training blade as a father’s day gift. I’d planned on a simple wooden trainer – but he had other ideas. After saying that “his dad deserved the best” – he talked over his options with me then spent the day in the shop making a rather awesome knife.

I was impressed, as it was a lot of time-consuming work. We started with an old piece of scrap, a half finished milling prototype for a knife I made a while back. He used files to finish shaping the blade. The blade was made out of aluminum, and he insisted on 5 sanding passes to get the blade face to look just right.


Once he was happy with what the blade looked like – we stamped in his dad’s name on one side, and “I love you dad on the other”. He even made sure we checked that “I love you dad” would be right way up, and readable, when his dad was using the knife.


We watched a bunch of YouTube videos on para-cord wrapping knife handles. Once we found a pattern he liked, we drilled the handle and he wrapped it up.


It was a tricky process, as he had to hold tension on the cord, while setting the pattern on the top and bottom of the blade. I offered to do the wrapping, but he wanted to do it.


In the end I was really impressed with what he made. It is a sweet training blade in itself, but my nephew was right – you can read “I love you dad” when you are using it, and thats just awesome.


Get the Tank out

I think that figuring out a way to make cheap yet pressure reliable hatches is going to be the defining design criteria for all my AUV designs. Shifting the CO2 tank to outside the hull lets me use smaller hatches, which will be easier to build.

This “Cyclops” design is my experimenting with that shift. There are two tanks shown, a 24oz and a 12oz. Tank size will drive a lot of the design – so I have taken to having both visible when sketching out a hull design.


I’m starting to think I need to introduce some more separation of all these variable before I start building – so I may do spin up a design with a smaller hull to work out technique and construction details.

American Munkki for breakfast!

So first – let me say – oh my lord the Finnish people know how to make a good doughnut! This was black licorice on a cake doughnut with black coffee. The combination was awesome. The Finns have what is basically a really nice doughnut – in the same way that a Portia and a Volkswagen are both cars.


Anyway – given that there had been a bit of a cultural gaff between me an Klaus regarding Americans and bringing doughnuts to work on your first day, I figured I would pick some up for the office as a joke.

Moving the machine shop

Moving your machine shop is like a reverse barn building, only in this case your friends show up and start taking things apart. In this picture Joel and Ben are about to lift the head off of my mill.


It was a long weekend – but we broke down my machine shop and moved it 1200 kilometers into Ben’s shop. Having shops and a lab is awesome, but they do sort of keep one foot nailed to your home base. Ben is being nice and taking care of the machining equipment for a few years, enabling me to be more mobile and do some traveling.

Ben recorded the move – so we have this video.

If this all seems like some high testosterone weekend – it was quite the opposite. I spent as much time making flowers from gravel on the driveway with one of Ben’s daughters as working on the equipment. Sure – that was mostly so ben could work on things undistracted, but I actually had a lot of fun. Getting older is both fun and weird.

Wooden Kitchen training Knives – (part one)

I’ve wanted a set of wooden kitchen knives for a while now. All the training blades I have ever run across were all patterned after crazy blades meant for poking holes in, or cutting, other people; basically large combat or hunting blades.

For knife work, I figure that if I ever have to defend myself form a knife attack, it is way more likely that my attacker will be using a weapon of opportunity than pulling out some crazy combat or hunting knife. Conversely, kitchen knives seem like a good pattern to practice basic knife attacks – as they are easily found most homes. So I am making a set of kitchen patterned training knives.

I started with some holly that I had harvested a few years ago.


The piece of holly I started with was fairly thick – so after cutting out a knot
I planed the rough cut stock flat on both sides, cut the stock in half, and then planed it flat and to the desired thickness.


From there I traced the pattern of the pattern of the knife in question onto the wood. I tried and pick a location and alignment with the grain that will work best for the knife pattern in question.


The next step is gluing on the handle scales. Holly is a very white wood, so I am glueing on American cherry scales. I’m hoping after a few coats of linseed oil it will finish off nicely. The scales are taking forever to add since each side takes a day for the glue to dry.

Dam you Farmers Union iced coffee!

Dam you farmers union iced coffee, despite my best efforts you drew me into your madness. Even 8 years later I see something like this on the shelf and think, maybe this is the one, something like you that I can get outside of Australia. I get my hopes up. Then I have it, and its just bad coffee and milk.


All these years later and I am still getting my hopes up when I see something like this. Dam you Farmers Union. Dam you. You are liquid evil.

Improved Ammonia Fountain

The big improvement was replacing the surgical tubing with fish tank tubing from the pet store. A chemist friend tipped me to the fact that with just a little Vaseline, the fish tank tubing will slide onto 6mm OD glass tubing we are using and make a great seal. That seemed to work great, was cheap, and was much easier to work with. I also increased the inverted NH3 catch flask size from 250mL to 1000mL. That should make for a better looking fountain.

In order to detect when the flask was full of NH3 I used a clothespin to clip a litmus paper inside the flask stem. Last time we just bombed the flask with way more gaseous NH3 than needed. It worked, but was inelegant. The idea with the paper was filling the flask to have just enough gaseous NH3 to work. Turns out the paper is hard to read when reacting to gaseous NH3.


It turned out we filled up the flask partially with ammonia – but nowhere near as much as we needed to draw enough vacuum to trigger the fountain, just enough to trigger the litmus paper. The whole point of these projects is to get a better feel for physical chemistry, and practices at the lab work. So I did learn a lot, but it was still frustrating.

Training Nukite on the Makiwara

The Makiwara has done more to clean up my strikes than anything else. It regularly teaches me new thigns and shows me how things I thought I understood were wrong.

Well karate has a number of finger and nuckle strikes that I have only recently gotten to the point where I have added them to my stiking practice. Only problem is even soft strikes just killed my fingers. My sensei showed me a neat trick to work on my finger strikes. Basically you hang a punching target from the makiwara, then do your strikes against the pad. After a few months I was able to work up to striking the naked makiwara.

Nuke strikes on padded Makiwara

The big problem I am trying to figure out currently is my pinky finger hanging out from my hand during the strike. It does not seem to impact the stike, but I cant help thinking that having the one finger separated from my hand has the potential for it to get hung up on the harget or broken.

Pinky problem

Now that I am regularly practicing Nukite, I can see how I am doing it wroge all over the place. Pinan Shodan for example has a Nukite strike to the throat, and I can now see I was just thrusting with a knife hand during the kata. My finger position was all wrong. So now I need to fix my Kata and my strikes.

(3D printer + awesome nephew) = Toys!

So I have be playing with 3D printers for the better part of a decade – and I cant believe I never though of this! Most of what I do is making parts for prototypes – I haven’t been making toys.

My nephew is in town and I wanted to show him what you could do with a 3D printer. He’s 8 – and awesome – so we made some accessories for a Nerf gun under his direction. Once we were done with that though, we found this guys design for a mini-fig walker. (Design here http://www.thingiverse.com/thing:171087).


The designer painted his, which looks better, but I don’t really want to give kids painted parts to play with. They tend to end up in their mouths. Turns out there are a bunch of interesting designs for mini-figs out there.

At this point I pretty much need to design and make my nephew some new toys, but until I have time to sit down and design something for him myself, these designs look neat.

Lego Walker http://www.thingiverse.com/thing:462844
MiniFig Mech http://www.thingiverse.com/thing:22834
MiniFig Mech 2.0 http://www.thingiverse.com/thing:22835

Thing a day, Thing #23 Hex Wrench Rack

I am working on a few side projects at the moment and took a few days off from thing a day. I’still am shooting to wrap up the experiment on thing #30. So to get back to it – things number 20, 21, and 22 were more drawer liners and look just like things 13, 14, and 15. Unfortunately I have a lot of drawers that I want to make liners for, so I am chipping away at them.

Thing number 23 is another tool rack. I have been building a couple projects that all use hex nuts, and are spread over multiple benches in the shop. Figured I would make a traveling rack for hex wrenches.


This is the first time I used ball end wrenches, and I have to say – I really love them. Specifically, they let you drive the hex nuts from an angle of up to 30 degrees. As mechanism get more complex that’s a really sweet benefit.