WOOF group has spent the last two months researching. engineering, extruding, printing, and dumpster diving for the greater good. WOOF submitted the first 3D printed milk jug boat into the Seafair Milk Carton Derby. Not a simple task, they hacked a 4′ x8′ plasma cutter, slapped a homemade extruder on, and dealt with 2% shrinkage, to produce a beautiful boat. The boat weight is 40 lbs (~250 1 gallon Milk jugs) supports 150lbs, yet cuts through the water like a canoeyak.
After spending weeks in a dumpster, sorting milk jugs and cleaning them. Scrapblasters was gracious enough to do some controlled small batch shredding to maintain clean mix of only #2 HDPE milk jug plastic. WOOF was finally ready to print. With the hopper feeding beautifully, the first test print was a success.
Scaling up the process had its own trials, but the WOOF team has a diverse group who balance out problem solving with skill and ingenuity. They worked with materials that were cheap, effective, and readily available. This technology has great application in many third world countries, and islands where plastic processing is limited or, the materials must be shipped off island. However the greatest contribution is not the plastic being reused, but the land and water masses it reclaims turning them from dumping sites to useable spaces and ecosystems.
More about their printing process is available on their Blog http://fabbersuw.blogspot.com/ (or click WOOf @ UW) on the right.
There was some confusion when WOOF entered the Derby about what class they were in. They had come to race, but it wasn’t clear whether or not they qualified. No one knew what to think of a boat printed out instead of the traditional strapping of cartons to a structure. WOOF was placed in a Group category due to some confusion, and the boat required some explaining.
Yes this is made of milk jugs. It weight 40+ lbs which is ~ 250 1 gallon milk jugs. In fact this is the only boats that is 99% Milk jugs. 1% weird stuff that fell into the hopper. Thankfully, a commitee decision by Kyle and Andrew (from the Seafair) placed WOOF back in it’s original racing category. After receiving the notice that their racing status had changed, Matt Rogge and Adam Commons loaded the boat in the water 5 minutes before the race.
Matt Placed 2nd in the 14+ heat
Denny’s Seafair Milk Carton Derby Rules & Regulations
A. The derby is divided into several age and vessel categories. A boat can be used for only one age and entry classification. And only once within that age and entry classification.
B. Only the following types of cartons may be used to provide flotation: one-half gallon, one gallon milk or juice cartons or one gallon plastic milk or juice jugs.
C. A minimum of 50 one-half gallon milk cartons is required for each entry except in the Commercial category where a minimum of 100 one-half gallon cartons is required.
D. Please arrive at least one hour ahead of the event you plan to enter. Entries must be classified and inspected prior to registration. Registration closes 30 minutes prior to each event.
E. All participants must sign a waiver/release form and turn it in on-site at registration if they have not pre-registered online. If you are a participant under the age of 18, your parent or guardian is required to sign the form.
F. No one under the age of 8 is allowed on an entry unless accompanied by an adult
G. Each participant must wear a U.S. Coast guard approved life jacket while in the water, and must have them at time of inspection. Ski belts are not acceptable.
H. Showboat awards are based on creative use of milk cartons, originality and workmanship. The use of creative materials, design and methods of movement is encouraged.
I. Entry must have a pole or minimum 18” x 18” vertical flat surface to which an entry number can be attached on the right side (shore side).
J. Entrants are expected to transport their entry away from the site, or disassemble it and put it in the garbage dumpster provided down by the boat launch area. Your help in keeping the area clean is appreciated.
K. Crafts must be of home-made construction and primary flotation dependent upon milk cartons. Waxing, shellacking or covering the hulls with material such as plastic, packing tape, lamination or metal is not allowed. You may use chicken wire or plastic mesh.
L. Do not enclose the bottom of the vessel, leave it open so inspectors can examine your boat for compliance to derby guidelines.
M. Fixed oars are not allowed in the Open or Commercial categories.
N. No engines or motors of any kind are allowed. Propulsion power or any other kind of stored energy (i.e.: tank filled with compressed air or water) is prohibited. Sails will be for decoration only and not for power. Human power only.
O. Any propeller or mechanical device must be covered by a protective enclosure. This includes chains, belts, paddle wheels, side wheels, sprockets, etc.
P. Contestants will begin the race in their boats at the starting line indicated by the starting buoys. Any boat crossing the starting line early may be disqualified. Boats must remain in their own lanes. Judges may disqualify vessels impeding the progress of others.
Q. Boats must stay inside the designated course.
R. Vessels must remain in the same configuration for all events.
S. Nothing is to be thrown or released from boats while in the water. Decorations must be firmly attached. Violation is an automatic disqualification.
T. Prizes in all other categories are based on speed and will be awarded to the first entrant who crossed the finish line.
U. Participants must be present to win prizes.
V. Inspectors will classify each boat prior to registration and will inspect each vessel to make sure that it fits within the rules and safety guidelines outlined above. Racing style boats will be entered into the Racing Category only.
W. Any boat not built according to Seafair Milk Carton Derby Rules may be disqualified.
X. Decisions of the committee are final.
P.S. The University of Washington issued the following press release which includes a short slide show.