DIY JR27 Sled

About 15 years ago, I found instructions of how to make a sled with household tools and easily available materials. Already then, the internet was filled with stupid, more stupid, and impossible instructions of pretty much anything. Therefore, I almost ignored this “too good to be true” sled plan. Fortunately, next to the instructions there was a picture of the guy behind the plans, and I realized that I knew him. He was my former teacher from the department of genetics at the university of Oulu, and I had never heard any BS from him, or of him. Therefore, I decided to try to build his Ultimate JR27 sled. I followed his instructions to the last detail (except for the canvas belt, which I replaced with a leather one), and the end result was an absolute success. (Unfortunately, the original plans are only available in Finnish, but at his pages you can find some very nice drawings and measurements of the sled.)

Since building my sled, I have used it in every single winter trip to our hunting cabin hauling food, fuel, and clothing with unbelievable ease. In fact, in the last 15 years I have learned to not pay much attention to the amount of stuff I pack into my car during the winter time. Why bother? My sled can handle that.

This begins to sound like an average internet review of some worthless gadget that has been tested by reading the package insert and walking the gadget around the garden once or twice. Where is the real field test?!

Fortunately, this particular type of sledge has been tested. In 2004, a guy named Erkki Lampen skied from south coast of Finland to the northern most border of the country. It took him a good two months and 1200-1300 km (750-800 miles). He hauled his 50-60 kg (110-140 lbs) load with a home made JR27 sled. During his epic journey, he kept an online diary with daily text messages, and I was lucky enough to notice that and follow his whole trip. According to his diary, especially for the first hundreds of kilometers in southern Finland, he dragged the poor sled in not so good snow conditions, sometimes practically on gravel. Due to the treatment of the sled, after about 800 km of skiing, a runner of the sled broke, and it had to be replaced. No other serious problems during the trip. After the trip he wrote that if he would do the same thing again, he would use 15 mm runners instead of the original 8 mm, and replace the 10 mm fiber glass tubes with 15 mm tubes.

As a conclusion from his experiences, and mine, I would say that the JR27 is pretty well tested, and if you are going to drag ridiculous loads on gravel and steep hills, thicker runners and pulling bars are recommended, but if you rank yourself mortal, the original design does its job very well.

As promised on the video, here are some building instructions:

Materials

For the sled:

4 m (13 ft) 4 to 5 in wide, 12 mm (½ in) thick board

0.5 m (20 in) 2X2 in wood

40X200 cm (16 in X 7 ft) sheet of 1 to 2 mm (1/24 to 1/12 in) high density polyethene (HDPE)

Two 180 X 2 cm (6 ft X 4/5 in), 8 to 15 mm (1/3 to 5/8 in) thick strips of HDPE

For the pulling gear:

Two 2 m (6 ½ ft) long 10 to 15 mm (2/5 to 3/5 in) glass fiber tubes

1 m (3 ft) 10 to 15 mm (2/5 to 3/5 in) id rubber tube (coolant tube from a car)

One belt

For covering and binding the cargo:

1.5 X 2 m (5 X 7 ft) tarp

5 m (17 ft) of 6 mm (¼ in) bungee cord

4 to 5 pieces of 10X2X1.5 cm (4X4/5X3/5 in) wood

For attaching everything together:

Duct tape

4 hose clamps

Some screws, rivets, staples, and nuts and bolts

 

Work flow:

Cut the rear panel from the board symmetrically so that the top and bottom lengths are 42 and 32 cm (16 ½ and 12 ½ in), respectively.

Cut the front beam from the 2X2 in wood to the same angle with the rear panel so that the top of the beam (the longest side) is 41 cm (16 in).

Cut the side panels to about 170 cm (6 1/2 ft).

Shape the side panels as seen in the video.

Drill the holes for the screws (2 for each corner).

Screw the frame parts together.

Plane the bottom edges of the side panels.

(If planning to paint, do it now)

Attach the HDPE sheet to the front beam with screws and washers.

Place the HDPE strips against the bottoms of the side panels (HDPE sheet between the runners and the side panels).

Drill holes for the screws (12.5 cm (5 in) intervals) using a thin drill bit.

Drill sink holes for the countersunk screws with a bit thicker drill bit .

Attach the runners and the HDPE sheet to the side panels with the countersunk screws.

Attach the rear end of the HDPE sheet to the rear panel using screws and washers.

Cut four 20 cm (8 in) pieces from the rubber tube.

Drill holes to the side panels and attach one tube to the each side of the sled using two bolts and nuts per tube.

Rivet remaining tubes to the belt so that they are evenly on both sides.

Wrap the ends of the fiber glass tubes with 2 to 3 layers of duct tape.

Slide the fiber glass tubes into the rubber hoses and secure with hose clamps.

Staple a piece of tarp close to the interior bottom edge of the side panels.

Thread the bungee cord through the holes on the side panels and the wooden locking pieces.

Pack the sled and go.

Mini Trangia and winterizer at -32.6 C

About a year ago, I tested my home made winterizer for the Mini Trangia alcohol stove at –25 C (-13 F). To my great surprise, my “not good at really cold weather” Trangia managed to boil 500 ml of +4 C (+39 F) water in about 7 minutes, mainly due to the help provided by my DIY winterizer.

Since then, it has been ridiculously warm, and now was my first opportunity to try to find the limits for an alcohol fueled stove.

So, this is how it went. First, I left the stove and the fuel outdoors at -32.6 C (-26.7 F), and 500 ml of water into the fridge for overnight.

In the following morning, I loaded sthe stove and soaked the wick of the winterizer with -32 C alcohol (Note to self: Do not spill it on to your fingers. It is damn cold!). Despite the syrup like behaviour of the cold alcohol, lighting up the alcohol soaked wick was very, very easy. However, due to the 5 m/s wind, it took albout 13 minutes to bring the water to boiling. Therefore, I repeated the experiment using a simple windscreen made out of fire retardant fabric.

With the windscreen, the boiling time was reduced to 9 minutes and 40 seconds.

As conclusion, with a proper protection from the wind, an alcohol burning stove (with DIY winterizer) still works beautifully at -32 C !

As soon as the good old -40 to -50 winter days (hopefully) return, I’ll test and report whether there really are any limits for my little Trangia stove.