Introduction: Make Your Own Ski-pulk
Yukonstruct paired up with the Yukon section of the Alpine Club of Canada (ACC) to offer a pulk workshop. In Yukon, ACC members go on ski trips year round, a couple of members just got back from over a month on the icefields skiing and mountaineering to summit Mt. Logan (Canada's highest mountain; 2nd highest in North America).
A pulk is a low toboggan that is pulled behind a skier (or a dog or, according to wikipedia, a reindeer as well). It is used for transporting things, and is perfect for long ski trips.
We built a Paris expedition style pulk with ridged poles. All ideas were found in the Pulk Book, a free online PDF and adapted to work with materials that are easily sourced in Whitehorse. You can also go to skipulk.com for purchasing their products and info.
Step 1: Materials and Tools:
This build will require at least a full day and uses common power and hand tools.
We will break the build into three sections. The first two sections can be done in any order. Read through each section before you start as an overall understanding of the component may help clarify the step by step tasks.
Personal protective equipment like safety glasses, hearing protection and gloves should be used as this project causes metal filings, fiberglass burrs and loud noise when drilling.
NOTE: SS means Stainless Steel
Section 1: Poles:
Materials:
- 2 X Fiber glass poles 3/8" x 72"
- 4 X coupling nut 5/16"
- 2 X tie rod end 3/8" male
- 2 X forged eye 5/16" short
- 2 X split pin 5/64" x .75"
- 4 X heat shrink double wall 3/4"
- 1/2 package of 5 minute epoxy
Tools:
- Hack saw 32tpi
- File half round bastard or flat
- Drill or drill press with drill bits (5/64", 21/64")
- Heat gun
- Tap and Die 3/8-24
- stick and container for mixing epoxy
- cutting oil
Section 2: Sled Mounting Brackets:
Materials:
- 2 X Sq Alum Tube 1.25"x 1/8" x 6'
- 12 X SS reg washer 1/4"
- 4 X SS bolt 1/4" x 1"4
- 6 X SS Nyloc nut 1/4"
- 2 X grd 5 bolt 3/8" x 3.5" (for pin)
- 2 X Aluminum bar stock 1" x 1/8"x 4.5"
- 2 X Sm cotter pin (bobby pin style)
Tools:
- drill or drill press with bits (3/8", 1/4", 1/8")
- Hack saw 32tpi
- File half round bastard or flat
- wratchet and wrench 7/16
- Bi metal hole saw 2.5"
- Cutting oil and anti seize thread dope
- small hammer (smooth face)
- vice or clamps with 3.5" mouth
Section 3: Pulk:
Materials:
- pulk shell - we used the Paris Expedition Style Sled.
- perimeter cord 4mm x 4m
- 2 X brake lines f/b 6mm x 1m
- 4 X straps 1" x 1m
- 4 X buckles 1"
Tools:
- cordless drill with bits 3/8", 3/16" and 1/4"
- sewing machine
- Knife and lighter
- measuring tape and sharpie
- dremel with cut off disk
Step 2: Pole Construction
1. We will start with the metal work first. Make a mark on the coupling nuts centered between both ends (do this on all 4 nuts). Mark two of the coupling nuts to make them different - here we marked them with a star (Photo 1), these are the ones we will be working with first.
2. Lock the star coupling nuts in some kind of vise and drill out the threads using the 21/64” bit (Photo 2). Then using cutting oil and the 3/8”-24 tap, cut new threads the entire length of the nut (Photo 3).
3. Drill a 5/64” hole through the nut between the mark and one end. This will be the end that eventually gets epoxied onto the pole and later pined with the split pin.
4. Measure half the length of the coupling nuts and cut the forged eye bolts and tie rod ends down with a hack saw so that they only fill half the coupling nut. Use a file to fix threads. Leave the nuts and ends assembled so that the half of the nut with the 5/64” hole is empty. (note that Nuts marked with a star will only fit the tie-rod ends) (Photo 4)
5. Take the fiberglass poles and cut off any reflectors or ends they came with if you’re using driveway markers. Make sure these are the same length when you’re done. (Photo 5)
6. Each pole gets a forged eye and tie-rod. Knowing this, pair up and mark unique id’s to each pole and end assembly. (ie. A is marked on one pole end and one forged eye nut assembly).
7. Take the 3/8”-24 Die and use it like a pencil sharpener on both ends of both poles. Take care to not cut more than the empty half of the end assembly. The shoulder left by the die should bottom out on the rim of the coupling nut before the end hits the eye/tie-rod already installed. (Photo 6 and 7)
8. Trim any burrs with a utility knife. Slip 2 pieces of heat shrink tubing to the center of each pole.
9. Mix epoxy, apply it to one end and affix the correctly labelled end assembly. Repeat on all four ends making sure that the forged eye and tie-rod end are aligned in the same plane. After 2-3 min back off the forged eye/tie-rod ends a few turns from the coupling nut to prevent the epoxy from gluing them in permanently. Take great care in not moving the coupling nut and fiberglass (Photos 8 and 9)
10. Even though it is 5 min epoxy, let it sit while you moving onto other sections of the build.
11. Once it’s sat for at least an hour and you’re sure the epoxy has hardened, drill out all the 5/64” holes again and gently tamp in the split pin. Use the file to make them flush with the facets of the nut.
12. Slip the shrink tubing over each end of the coupling nut and use the heat gun to shrink down. This will hide the fiberglass/epoxy/coupling nut area prevent undo wear here. (Photo 10)
13. For a nice finishing touch you can tape the center 6” of each pole with a rubber tape and use a Velcro cable wrap to make sure they always cross in the middle. (Photo 11)
Step 3: Sled Mounting Brackets
1. Take the square tubing and clamp them together. Preferably using a drill press, cutting oil and the hole saw, cut through the metal (Photo 1). This will create two half circle brackets (Photo 2). File off burrs and clean off oil.
2. Drill a 3/8” hole through the semicircular faces of each bracket, centered ½” from the highest point (not pictured).
3. Drill a ¼” hole at both ends of the bottom of the bracket, centered ½” from the edge (Photo 3).
4. Take a 1” bar stock piece and use the hacksaw to cut it to 4.5" (Photo 4). Clamp it to the bottom of the bracket with one set of ends flush. drill the ¼” holes in the bracket through to the bar stock (Photo 5). Drill one addition hole centered ½” from the remaining end of the bar stock.
5. Take the 3/8” bolt and cut off the threaded portion with a hack saw. Making sure it is at least 1 5/8” of smooth rod (Photo 6). File or grind a bevel around the cut end to remove burrs and ease the insertion into the bracket. Drill a 1/8” hole through the end about 1/8” or so from the end to allow the cotter pin to secure the bolt once it’s though the bracket (Photo 7).
6. Test fit all pieces and make adjustments if necessary so that all parts fit nicely. (see notes in Photos 8 and 9).
Step 4: Pulk Construction
1. Start by laying out the brackets on the pulk. In the front corners find a suitable place where brackets can sit slightly toeing in at the front. Make sure the bar stock can lay flat under the lip. Once you have your location. Drill the front hole first and place a ¼” bolt through the bracket/pulk/bar stock assembly. Drill the next hole inserting a bolt after and finally the last hole just through the bar stock pulk. Inserting a bolt as you go assures everything lines up.
2. Fix the bracket in place with the SS hardware and use anti seize to prevent cross threading. (Photo 1 & 2)
3. Next layout all the holes for the cord and straps. Use pre-existing holes where possible. Keep in mind you want the cord to be more often above then below the lip of the pulk.
4. When laying out the holes for straps space things as follows: 3/8” hole _ 7/8” space _ 3/16” hole _ 1”space _ 3/16” hole _ 7/8” space _ 3/8”hole. Measurements are all to the center of the hole.
5. Once all holes are drilled use a dremal to cut slots between all of pairs of 3/16” hole and smooth with a file.
6. Take 1” webbing and cut 50cm pieces so you have a total of 8, with one end cut at 45° on each piece. (Photo 3) Fold over the 90° end 1” and sew across the entire width on all pieces so you have a flat loop.
7. Starting at the front of the pulk, thread the 4mm cord around one side. When you get to a strap slot, insert the sewn end of a strap and pass the 4mm through the loop before coming back up above the lip. Once you have completed on side. Do it with the other so that the ends of the 4mm meet centered at the back. (Photo 4)
8. Work out any slack in the 4mm and tie a double fisherman’s knot under the lip. Cut and melt ends leaving 1.25” of tail.
9. Drill an addition 3/8” hole in the front and back corners (or use factory grommets). Cut the 6mm cord into two pieces. Tie a triple over hand in the center of one, this is the front break. Pass each end of the front break cord up through these corner holes and tie stopper knots in ends. (Photo 5)
10. Do the same with the back break but pass the ends down through the corner holes and tie stopper. (Photo 6)
11. Lastly attach 1” buckles to strap pairs making sure to have females on one side and males on the other. This will allow for cross strapping when required. (Photo 7)
Step 5: Assembly and Final Notes
Assemble poles and pulk together and take on a day trip before your next big adventure to make sure it all works together.
Attaching the pulk to you. You can find ways to clip it to a pack or climbing harness or sewn something like a skijoring belt with webbing loops to attach. Attachment methods can vary widely and were not covered in this workshop.
Adventure on!