Toboggan Build

[Dave]

Part 1

Hope to have this finished by next week, I'll just post photos as I go.

First job, sanding down a piece of unfinished american white ash, from the timber yard.

The sheet of PE1000 is TIVAR, and 15.78" wide, 9.8 feet long.
Measure the sled blank, and cut it out, making it 'coffin shaped' or tapering at either end.
Front end, 2" in from either side, 2 feet along the length.
Back End, 1" either side, then 2 fet down the length.
Cut with a jigsaw, and finish with a handheld plane.

 

[Robson Valley]

Good. The boat shape will carve in the snow in a straight line.

 

[Dave]

Oh, thats why they do it. I've been asked, but didnt know. Makes sense though now, thinking about it.
I just know the better manufacturers, black river sleds, LOTN, do it. Cheers Robson.

 

[Robson Valley]

Plain rectangular ones often skew sideways on the least bit uneven ground, hook an edge and roll over.
I put 3 fillets of wood under mine to act as keels. Helped a lot.

 

[nic a char]

2 skis on a platform

 

[Robson Valley]

That's fine if the snow is compacted from travel (trail) or a warm spell of WX.
Sleds with rails, like the dog sleds of the Iditarod race, travel at frightening speeds with a big team.
Much of the race course is wind-drifted so easy even to stand on without punching it down.
Toboggans, long ones, will track well with a load.

With a big dump overnight, flotation surface area is important where I live. Biggest in 15 years here was a measured 36" last winter.
We have 300km of groomed XC ski trails, warming huts and so on. Don't know how many km of groomed snowmobile trails.
Getting a $20k snow machine bogged is a very costly recovery operation ($2k cash up front to go have a look-see.)
Up top, might be 30-50' of snow in places.

 

[Dave]

Part 2.

I bought 25mm m6 bolts from screwfix, along with m6 4 pronged T- nuts, and a bag of m6 nylon locking nuts.

First the Bolts did not have a flat enough head, so we grind those down a bit. Because these will be coming up from the bottom through the Pe1000.


After grinding they are much flatter heads. See side by side comparison:


With a bit of imagnation, you can see here, how the now flat headed bolt, will go up through the pe1000, and after I have countersunk a hole big enough to hammer in the threaded 4 pronged T-nut, it will screw into it, then from the top the nylon locking nut will sit flushly will screw tighly on, and sit below the surface of the wooden strut.

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Laid out, you can see the mummy shape taking place of the sled, with the 5 struts to be drilled, countersunk, routed on the underside, to fit the 5mm running cord, before being varnished with marine spar.


TBC

 

[British Red]

Awesome project Dave...I'm "following"

 

[SGL70]

Awesome project Dave...I'm "following"

What he said...

 

[British Red]

I must say though, your Aldi grinder on a workmate gives me the heebies

 

[Robson Valley]

You have just taken me back more than 40 years, snow shoes and all. Keep it up.

 

[Imagedude]

Started my build today, and finished it bar the final tweaking too.

 

[Dave]

Is that all youre taking? No Ski's then?

 

[Dave]

Awesome project Dave...I'm "following"

What he said...

You have just taken me back more than 40 years, snow shoes and all. Keep it up.

Cheers Guys will do. Dont worry about the bench grinder Red, it wast that bad.

 

[Imagedude]

Is that all youre taking? No Ski's then?

Depends on the weather but will probably just take snowshoes.

 

[Dave]

You'll have to post a kit list Bob. How big is the ruck?

 

[Imagedude]

Bout 100 litres...I've never had a kit list, makes packing more exciting...

 

[Dave]

Bout 100 litres...I've never had a kit list, makes packing more exciting...

I'll be taking [probably] 2x80 litre black brit army deployment bags, a tough alpkit drybag, and a canvas day bag. But I think I might get a load of fresh.
Steak everyday, as we'll be in a freezer, and Ive got a big sled.

Something else I dont know, if you need a bear bag, even in winter, when they're hibernating, or can we just cook at camp? Your tents big enough to cook in right?

 

[Dave]

Part 3

Drilling the struts. First measure where you want them to be, and clamp the struts on the tobbogan, then using a pilot bit, the same diameter as your 25mm bolt which will come up through the bottom of the pe1000, drill down through the ash strut and the pe1000.
Then sing a 3/4" countersink, marked at 12.5mm with tape, drill down into the ash strut.

Then take the clamped ash strut off the tobbogan, and using a slightly bigger drill bit, drill through the pilot hole. [Just the pilot hole, not the pe1000!]
This is because the 25mm bolt comes up through the bottom of the pe1000, and screws into the 4 pronged T nut. [Pictured below on the strut]
So the diameter of the [female] 4 pronged T nut, is slightly larger than the diameter of the 25mm bolt.
The hole in the pe1000 is a smaller diameter than the hole in the ash strut.

You can see in the photo below, the bit on the right is the same diameter as the bolt, and the bit on the left is bigger, the diameter of the 4 pronged T nut, present in the photo.




Then cut a channel using a router, and a 6mm bit, on the underside of the strut, to fit the 5mm running line, which will go down both sides of the toboggan, and be wrapped around each strut, with a clove hitch.


Dont forget to mark them before you take them off your tobbogan. [White 5mm running cord]
And cut a double groove in the middle of your back strut. When you make a grab handle at the back, you want it be connected to the whole running line, for strength, same principle as lacing a canoe.



Then clean it up with a small penknife and bit of sanding, and varnish with epifanes marine spar varnish.


TBC

 

[Dave]

Part

Next job, we take a countrsink slightly bigger than the diameter of the bolt head, on the slippy underside [Theres a slippy side and a rougher side]
We countersink just 1mm or so, so that the sanded flat boltheads sit just below the surface of the slippy side.

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There is some plastic scurf, around the countersink which is best taken off with a small penknife.




Then we add the nylon locking nuts to the top, coming up through the pronged T nuts, and its an absolutely rock solid construction.