more library books

What do you get when you pair architects with minimalist artists and turn them loose on media (snow and ice) they have little or no experience with? The Snow Show is a book filled with wonderful, full-color photographs of the results, creations that are beautiful and interesting enough to more than make up for being somewhat monotonous. Unfortunately, the book also features page after page of uppity, dysfunctional prose. Even the show's web site, with its "this experience is more important than anything else you could possibly be doing" full-screen presentation, manages to express the worst along with the best of the. . . Okay, I should stop now. Get this book for your coffee table and leave it there.

Snow Sculpture and Ice Carving is about as contrasting a book on the subject as could be imagined. A product of 1970's craft culture, James Haskins's book features black and white photos of sculptures that are more accessible if a bit crude. I didn't find the book terribly interesting, however, as it is heavy on ideas for what to carve but light on technique.

cams and hammers

Cam and hammer design has been the topic of much discussion lately. Lars and I both realized that, if we were to simply add extra pins to the cylinder on the original model in order to play all the notes in the tune, several of the pins would end up too close together such that a swinging hammer would crash into an upcoming pin before striking the chime (despite the fact that our tune features no rapidly repeating notes).

A related problem we've begun to consider is that we will have no control over the speed of rotation of the camshaft. There is no way to be certain that someone won't come along and turn the crank much faster than we would prefer. (Computer geeks like me call this an input validation problem.) Even if we have designed the pins so that they don't get clobbered by the hammer when turned at what we think is a reasonable speed, they could still be damaged when someone turns the crank too fast.

Yet another related problem is the speed at which the hammers swing. Since each one is essentially a simple pendulum, increasing the scale from model size means that the period also increases. It wouldn't do to have a hammer take longer to swing to and from a chime than the duration between two repeated notes, and that duration is completely dependent on the whim of the crank turner!

A solution we are likely to try is to use multiple hammers (probably two) for each chime. With only one hammer per chime, we will have repeated notes as little as 0.75 seconds apart, but two alternating hammers would increase the minimum repetition to 1.75 seconds (2.75 if we add a third hammer to the most frequently used chime).

Another solution might be to create some kind of mechanism to prevent the crank from being turned too fast or to prevent the hammers from swinging when it is turned too fast. Lars writes, "Once it gets colder, I might start building machine parts and putting things together at random!"

the healing power of touch

I went to the hospital cafeteria to see if I could get a bag of ice for a swollen ankle. They didn't have any bags on hand, so they gave me a latex glove to fill. It did the trick! I hurt the ankle by blocking a shot in a hockey game a couple weeks ago. It didn't seem to be healing very well, so I had it looked at. There was a faint line in one of the images, but doc says he doubts it is a fracture. It is a bone bruise that may take a while to fully heal, but I get to keep playing.

lathe improvements

Lars has recently made a number of improvements to the ice lathe he made last year. He added legs, a tool rest, and some kind of chucks to hold the workpiece in place. He writes, "the chucks work great! I had to keep tightening them as the piece was turning, since it's above freezing right now. . . . I wore a hockey helmet in case of disintegration."

ice chime workshop

I spent most of the weekend working on ice chimes. After a serendipitous discovery during the 2006 competition, it seemed that it would be fairly easy to make rectangular chimes out of ice. Unfortunately, it has been hard to improve upon the original, lucky design. Although it is difficult to produce large blocks of ice in Colorado's climate, recent weather has made it easy to produce slabs of ice by freezing water in shallow, cardboard boxes lined with garbage bags.

I had hoped to be able to make rectangular bars of ice attached at one end, but it has turned out to be difficult to get good tones that way. I've had better luck with bars that are free on both ends and attached about a quarter of the bar length from each end, like the bars on a xylophone. In fact, our music box will probably end up sounding quite a bit like a xylophone.

I made chimes of varying shapes and sizes and digitally recorded the tones they produced. Some handy, open-source software made it easy to analyze the spectrum produced by each chime. With bars free on both ends, the chimes produced tones as expected according to various sources identifying Young's Modulus for ice.

four weeks to go

The Single Block Classic will begin at 9:00 AM on Tuesday, February 27th, only four weeks away! Lars and I have registered and intend to build a working music box entirely out of ice. The sculpture will be based on the model Lars sent me a couple months ago, although we will have to change a few things.

The chimes will be solid and rectangular rather than hollow and cylindrical. The hammer mechanism will require significant modification due to differences of scale (long pendulums swing slowly) and material. We will have four chimes instead of one, enabling a tune to be played.

The tune will be Westminster Quarters, the familiar clock chime tune. As it was originally written for mechanical chimes not unlike ours, it has several features that make it well suited for our music box. For one thing, it only uses four pitches. Another nice feature is that no pitch is repeated quickly. Combined with the facts that it is universally recognized and continues our clock theme, these features made it an easy choice. The sculpture will be called "Counterclockwise."

There is still a great deal of work to be done in preparation for the event. Lars is making improvements to the wonderful power tools he made for last year's competition. I've been working on designing and testing chimes and hammers as well as making hot wire gear cutters.

orbital mending plate

I tried attaching a mending plate to my quarter-sheet orbital palm sander, but it didn't do anything but cut my thumb! (The injury was during installation; once in place it was actually quite secure.) I think the problem was that the little sander didn't move the abrasive surface enough in comparison to the distance between points on the mending plate. I think a device with a larger orbit would be pretty cool, though.

registered

We received an email confirming our registration for the Single Block Classic at the 2007 World Ice Art Championships. It's a good thing too, because I had already purchased my plane ticket. The Multi-Block event is already completely full, so there will be plenty of giant ice sculptures to enjoy this year.

mending plate

I had an hour to kill at a hardware store a few days ago, so I walked up and down the aisles trying to think of how to put various tools and objects to use carving ice. I picked up a Strong-Tie MP36 Mending Plate and thought it might make a decent, one-handed nailboard. (As my friend, Dave, would say, "This nailboard was mislabeled as a mending plate.")

I tried it today, and it works great! I guess I shouldn't have spent all that time making my wooden nailboard. Attaching a whole bunch of these mending plates to a board would be a very quick way to make a large nailboard.

hot wire gear cutting

Today I tested a new hot wire gear cutter made of balsa, copper, and 21 AWG nichrome wire. I cut an eight inch cylinder of ice with the table-mounted chainsaw and placed the cutter on top of the cylinder. I still need to make an axle-mounted guide to keep the cutter steadily moving vertically without tilting or rotating, but I decided to do the first test without a guide.

As current was applied, the cutter started to slowly work its way through the ice. My power supply was only producing about 50W; it was enough to do the job, but I'd like to find a larger transformer that will cut faster and enable cutting of larger gears.

The finished gear had several flaws due to the lack of a guide but otherwise was beautiful. Making cutters like this one will take quite a bit of time, but the actual cutting time is very short. I think that this will be our gear cutting method for this year's event.

chainsaw table mount

I tested a new table mount for my little, electric chainsaw tonight. It is made of steel flats and some nuts and bolts, and it allows the chainsaw to be used like a table saw but with more cutting depth.

My first use for it will be to precisely cut experimental ice chimes, but it may be handy during the competition as well. I also hope to use it to mill some boards from any trees I have to cut down this summer due to beetle kill.

The initial tests went very well. If Lars's 10", stationary, ice cutting, rotary bit doesn't make it redundant, I think we will find it quite useful.

It worked very well for cutting arcs and discs by inserting an axle perpendicular to the table-top and rotating the ice around the axle.

gear design tool

Steve Michel wrote to let me know about his amazing Excel spreadsheet for gear design. I probably won't need it this year, but I'll definitely keep it in mind for the future.

nailboard

I found my new nailboard to be quite useful while making the snowflakes. I used it to even out the 1/2" plates of ice out of which each snowflake was carved.

I made the nailboard a few weeks ago but didn't try it out right away. It works like a mega-coarse grit sanding block.

snowflakes

I carved a small sculpture of three snowflakes to take to a New Year's Eve party. I tried to photograph them illuminated by a small reading light housed in a small cavity in the base of the sculpture, but only a couple of the photos turned out to be useful. I really need to use a tripod for this sort of thing.

The snowflakes were about 0.5" thick and were pretty fragile. I think I repaired thirteen separate breaks while making the things. Fortunately, two out of three snowflakes actually survived the journey to the party! I think the sculpture would have been easier to carve on a larger scale, but I was limited by available ice.

I took a photo with flash as well. It isn't as pretty, but at least it captured details despite my unsteady hands.

library books

I picked up Ice Carving Made Easy, Practical Ice Carving, and Ice Sculpting the Modern Way from the local library. I have finished the first two but am still working my way through the third. So far, I haven't encountered very many insights that I hadn't figured out already, but a few tidbits have stood out.

Ice Carving Made Easy contained a couple of interesting points. One was the description of steam cutting in chapter three. Both Lars and I have been experimenting recently with cutting ice by bringing it in contact with metal tubing carrying hot fluids. According to the book, using steam in this manner is "still preferred by some carvers accustomed to older techniques" despite its slowness.

Chapter One, The History of Ice Carving, of the book includes some interesting details of the ice palace commissioned by Empress Anna Ivanovna in 1739.

"Inside, every detail was carved from ice. The highlight was a translucent clock with all of its interior mechanisms detailed, displayed on an ice table in the middle of the drawing room."

Could it have been a working clock? Considering that the palace was built some years after the invention of the Deadbeat Escapement, I think that it is possible. A clock of the size Lars and I hope to build would have been difficult with the technology of the time, as would a very small clock, but a table-top model would have been the most likely to succeed. Lending credence to the idea is the account of various other functional artifacts of ice:

"Six statues and an elaborate frontispiece graced the front entrance; two dolphins and one life-sized elephant fountain sprayed water 24 feet into the air. Two mortars and six cannons fashioned of ice were working replicas; they fired frequently. An ice-log bathhouse, also functional and used on occasion, completed the grounds."

package for Lars

I sent a package to Lars containing a hot wire ice cutter for him to try out. It consists of a home-made variable power supply (encased in a CD spindle shell) and a 10 inch nichrome wire on a wooden bow. Since receiving it, he has used it for cutting foam but hasn't tried it on ice yet. I'm hoping he will try it in cold temperatures to see if it causes ice to crack.

The CD spindle (with center post removed) turned out to be a great case for the power supply. I used a cheap triac dimmer switch, a transformer salvaged from a useless wall-wart, and a little fuse holder from Radio Shack.

robotic fishing hole carving

I ran across Jesse Hemminger's art shanty projects and enjoyed the read. The CNC lake ice router is outstanding, but I was even more impressed by the simplicity of the hot water pipe technique. I'll have to give that a try.

big, scary lasers

I found this amazingly inexpensive, 25W, 808nm laser on ebay tonight. I was quite tempted to buy it as it appears to be a very complete unit, including power supply, cooling, power meter, and output fiber. Unfortunately, it appears that ice doesn't absorb much at the 808nm wavelength, so I guess I'll pass on this one. I finally found an outstanding data source for optical properties of water and ice. Based on this information, I'd say I need a wavelength of at least 980nm.

laser cutting

Lars suggested using "high intensity lasers!" in one of his first emails when we started planning for Ice Art 2006. I laughed off the idea at first, but I'm taking it more seriously as time goes by.

Visible light lasers are certainly out of the question; they'd pass right through the ice without heating it. Infrared lasers, on the other hand, have a great deal of potential for ice cutting. Ice has a couple of peak absorption wavelengths at about 1500 and 2000 nm, but it looks like any laser in the infrared band would be worth trying.

I'm guessing that I need at least a 1W unit to do any meaningful experimentation, but the devices I've found so far are quite expensive. If anyone has lead on a cheap IR laser or laser diode (or salvage ideas), I'd appreciate it.

two turtle doves

This weekend brought good weather for ice carving practice, so I asked Emily what she would like me to make for her. "Two turtle doves," she replied. I have them sitting on a turtle shell, mounted on the deck railing by our front door. Apart from breaking off one of the beaks at the last minute, I thought the project went pretty well. I used a chainsaw and chisels on mediocre, home-made ice.