XC ski hot box wax for the Birkie and Vasaloppet (Cross Country Ski Base Prep)
Updated: Oct 19
[11/24/19 Update] Included a material list and better instructions for construction the box.
A couple of times a year, including just before the first big ski marathon of the race season, I like to deep clean the base of my skis using my hot box. Here's the process I follow:
Step 1: Prepare the ski
Brush out the skis with a fine steel brush to remove any surface debris.
Step 2: Soft wax cleaning
Melt in a soft wax (I use Fast Wax Base Prep, but any warm-weather wax should work), let it cool, then scrape the skis. This further cleans the base. The skis need to be as clean as possible before beginning the hot box process.
Step 3: Hot box wax
Next, melt a heavy layer of Fast Wax Hot Box Wax on the skis. Do not cool or scrape. Place the skis in a hot box set to 55 degrees Celsius for 2-4 hours. Remove the skis from the hot box, allow to cool, then scrape. At this point, the ski bases are cleaned and conditioned, but they’re very soft and are not ready for skiing.
Step 4: Harden the base
Melt in a layer of a mid-temperature blue wax (such as Rex Blue), allow to cool, and then scrape.
At this point, the skis are ready for the wax of the day, but I wont apply that until a day or two before use when the forecast is more certain and I can select the best wax for the race conditions. Note, even if a blue wax is the race wax I will use, I do apply a 2nd layer to the hardened base.
Hot Box Specifications
Cost: About $250 for Materials
4 Sheets 1/4" Plywood
(Each sheet can be cut to make a top/side/front or bottom/side/back)
2 Sheets 3/4" Foam
1x2 Pine - Enough to frame each piece (front, back, top, bottom, sides)
2x4 Pine - Support on left, right, and bottom
(3) 2x8 Planks - To form work surface
(1) 2x8 Optional - Ski Wax Support
750 watt electric heater
Dowels - For racking to accommodate 2 pairs of skis, or add more if you like.
Johnson Controls Thermostat
See Pictures and Video
Make top/bottom/back/front/sides. Sandwich 3/4" Foam between two sheets of 1/4" plywood. Use 1x2 frame around the edge. Glue and nail. Screw top, sides, back, and bottom together to form an open box. Cut 2 x 4 to make a frame around the bottom and sides. Hold out to allow for front to close flush. Mount hinges to bottom 2x4. Make catch. Line top with 2x8 to create work surface. Leave inside unfinished. Apply a coat of poly to the outside.
Other waxing technique notes:
-- While you can just use a clothes iron to melt your wax, it really is easier and more precise to use a specialized waxing iron. I personally use the Star digital waxing iron, and it has worked well for me.
-- The recommended iron temperature for melting is always listed on the wax box. If you can't set a temp, aim an easy melt with minimal smoking.
--If you don't have a hot box, you can still deep clean and prep your skis by simply applying three layers of a soft wax (cooling and scraping between each application).
--In my opinion, a hot box should not be used to melt in your race waxes, as to do so would require a higher temperature that potentially can damage the epoxy in the skis. Using a temp that is low enough to be safe for the skis will not melt racing wax so serves no purpose.