The Monkey Press
I press Monkeys in my custom built pneumatic snowboard press. The press heats both the top and bottom of the laminate to 175F with two 2,083 watt heat blankets that provide direct, even, controlled heat to the board to properly cure the epoxy. The combination of pressure and heat results in a very flat board on top and bottom, appropriate squeeze out of excess epoxy, and perfectly consolidated fiberglass layers.
The press cavity is 92″ long x 16″ wide x 12″ high. It is built with W12x40 I-beams. The long beams are 9′ long and weigh 360lbs each. Total press weight is right around 2,000lbs so far. There are two 5″ fire hoses which operate between 50-80psi depending on board surface area. There are two heat blankets, one on top and one on bottom, for a total of 3.5W/in^2. The blankets are 14″x85″, 240V for a total draw of 17.35A. It takes less than 5 min to heat a board from 70F to 175F.
The heater control has one PID controller with ramp/soak for controlling the heat of both blankets. Temperature is measured below the center of the board. It also has a second temperature sensor to monitor the heat transfer in other locations. It’s helpful to see the lag between the heat on the bottom and on the top of the board during pressing.
Air is controlled with a level in the center of the press. When off, no air flows, when on one position air fills the bladder, and in the 3rd position air escapes from the bladder thru a silencer. There’s also a pressure gague on the press to allow for fine control over the pressure.
The board comes out of the press with “flash” around the edges, which is the extra fiberglass, top sheet, sidewalls, etc. that extends past the edges of the board during layup. The flash will be trimmed off after the board has had a chance to further cure at room temperature for a few more days.
The mold is adjustable for different effective edge lengths, and different nose/tail lengths and rises. I tend to stick with a single camber block that has yielded good results for us over a broad range of shapes and lengths. I have an ever growing selection of nose/tail blocks. If a new block shape is needed for a particular build then I’ll design a new one and whip it up on the CNC machine.
Pneumatic vs. vacuum presses
The first few seasons of production at Happy Monkey were done with a vacuum molding system. This produced decent snowboards, but was a somewhat hit-or-miss process at times and presented some frustrating problems. We switched to a pneumatic press years ago and believe that it yields a superior product with fewer consumables used. The pneumatic press allows me to heat the laminate more thoroughly and consistently than did the vacuum system, and applies significantly more pressure which results in better squeeze out and a more consistent fiberglass layer.