Toboggan Curls

[Bothwell Voyageur]

Why do we still use such extreme curls on the front of freight toboggans? They must have had a purpose when they were made of wood but it seems to me that all they do now is waste space on the toboggan. Thoughts?

[kiggy]

aerodynamics?

[kiggy]

but a side of jokes, looks like it is best design to hold soft plastic in curved shape.

[Bothwell Voyageur]

It takes a fair amount of effort to get it to that curve and the running lines are required to hold it in that shape. Look at all that wasted space under the curve. If the front was curled up to some ground approximating to 60 degrees from the horizontal instead it would still float up and over the snow and free up a load more real estate.

[kiggy]

how it will hold the curve?

[Bothwell Voyageur]

Same way these do, with tensioned cords.

[kiggy]

Nice, so may be I was right joking about aerodynamics.
how it is performing in deep snow. do they always float? does it make sense to flatten curve even more? check the geometry of intuit sled.
i did some research looks like this is optimal angle to get sled on top of snow.

here is perfect example. looks like exact curve I have on my "fur" ski from Siberia

http://www.tipatshimuna.ca/1110_f.php?catalogue_no=pm30

[Bothwell Voyageur]

Seems to float fine as fas I can tell. I’m always walking in front so the toboggan is running in a channel in deep snow anyway. Maybe the tight curl reinforces the front, makes it stronger? I can see that would be an issue in wooden toboggans but I presume your ski is fine. It takes a lot of work with a hot air gun to bend the plastic to a tight curl so opting for a shallow curve would make production easier.

[Heavy Duty]

Without doubt, the full front curl on a toboggan increases the aerodynamic properties by streamlining the upper profile to interface with the toboggan tank.

In all actuality, I hope someone has a legit answer for this, I'm curious as well.

[Snowbound]

I always assumed it had something to do with how they used to steam bend wide boards with no form leaving the vertical rope so the curve doesn’t relax. I agree it doesn’t seem as necessary with plastic toboggans.

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[Bothwell Voyageur]

That looks a great picture.
Yeah, wonder what other ideas we need to update?

[kiggy]

how about fins and breaks?

[4estTrekker]

how about fins and breaks?

I built a short toboggan from a blank from Chris at Black River Sleds and did a fairly mild front curl. In terms of brakes, I incorporated a removable one into my wannigan for those pesky uphills (a la those found of many pulks). Keeps the toboggan from sliding back downhill. No luck for downhills, though. It pivots freely, can be flipped up when not wanted, and provides a bit of rear side-to-side stability. Seems to work great. Plus, the wannigan at the rear makes a great seat for riding the downhills. (As seen in my avatar.)

[Hamingredient]

Awesome thread, guys. I like the ideas and the innovation, here!

[4estTrekker]

I've also made a dedicated storage bag that fits the unused space inside the curl where I store my emergency "I burnt down my tent" kit (assuming I'd walk away from that). This includes my down parka, lighter weight anorak, down mitts, redundant survival/first aid/repair kit, etc.