Introduction: Snow Anchors
Lets make some snow anchors! As I found out in our last backpacking trip standard tent stakes don't work all that well in the snow and I really don't know why I thought they would :-) So I figured I'd make some large surface area snow anchors for my next trip. Here's a shot of the final product that we'll be making. For the UL backpacker these come out to 20g/each.
I'll be making these at the TechShop (link below) which has a ton of machinery and resources. One thing to note, I won't be going over the operation of each tool since you should've previously taken the safety/use classes. Obviously, this project is pretty simple in which you could do it with had shears and a drill OR a plasma cutter.... Anyways, here's my process.
Step 1: Buy Some Material
For this project I'm using 24 ga aluminum since it won't rust and is lightweight. The downside of aluminum is the oxide surface which allows moisture to cling to the surface and can be difficult to pull out of deep snow/ice. After some field testing I'll probably re-make these in Titanium but for now aluminum is adequate.
As for where to purchase material. Most all general stores have a small stock of aluminum but I prefer Alan steel in Redwood City, CA. Great prices and low cut fees.
Step 2: Draw Out Pattern
Alright, now that we have the materials it's time to sketch out the pattern. Here's a shot of what I'll be doing with an overall dimension of 4"x6".. Although not necessary, I've dotted out the hole pattern to you give a better idea. I've also attached a dxf for your convenience if you have access to a CNC plasma cutter and don't want to manually form it as I'll be doing.
Step 3: Beverly Shear
I used a Beverly Shear to cut the chamfers along the corners as shown the the pattern. Here's a shot of the tool. Pretty simple to use so there's not a whole lot of explanation I can give. With it being very thin and malleable aluminum you'll probably want to hold it down with a decent amount of force to prevent the start/end of the cut from rolling over.
Step 4: Hole Punching
For this next step I'll be using a rotary hold punch, you could use a drill as well but since I have access to this tool it makes the process go much faster. If you use a center punch for the holes the tool has a nice registration point on each die. See the pattern for hole diameters.
Step 5: Bending
Next step is to bend the material and give some rigidity to this super thin aluminum. I placed the part in the press 1" from each side and bent at 45 degree angle.
Step 6: Finishing
It's all done! Well, not quite.
At this point the product probably has some sharp edges and we wouldn't want to cut ourselves in the backcountry so it's time to round out the corners and use a deburring tool to clean everything up.
Now, it's done. If you haven't heard of the TechShop checkout their website for classes/equipment/membership, it's a great resource and worth every penny for all sorts of projects.
Step 7: In Practice
The process is pretty simple
- Determine the best way to attach cordage to the anchor. I'll get to this later.
- Pack down the snow where you want to tie off your tarp, or maybe tent guyline.
- Use a shovel, stick, trowel, etc... to dig out a hole lets say 8 inches deep or more. These are 6 inches tall and at an angle much less so 8 is plenty enough.
- Place anchor in the hole.
- Cover up
- Pack back down again.
- Use a short piece of cord and make a harness through the holes in which the actual taunt tarp cord will slide through (attached Image).
- If you end up placing a tauntline hitch at the tarp grommet the cordage can secured directly to the anchor.
- You could always place the tauntline hitch directly on the anchor although I've never tried this and have a feeling that in high wind situation with powder like snow it might create a sawing action and fray the cord. Maybe not...
It's also worth it to note that these are by no means a load-bearing device as the term "anchor" may imply. It's just simply a means to secure a tarp or tent in snow which may otherwise prove to be difficult with standard tent stakes.