Tent Stake Input

[Lawson Kline]

Hi Everyone,

I have been looking into the idea of making my own Titanium V stakes for a while now and I would like to get some feedback. My design is similar to a conventional V stake but its wider at the top and narrower at the bottom for improved driving depth in harder soil's. The first set of stakes are most likely going to be 6.5" long x 1" top x .5" bottom before bending, with a total weight between 7-8 grams. I will probably make a longer and wider version for bigger shelters and looser sand/snow but I am not sure of the size yet?? In addition to the improved design I also added a hole at the bottom center of the stake. The hole helps the stake to work better in loose soil/sand. A few years back I took some V stakes and drilled a hole in the center towards the bottom and they have been working great ever since. I tie the guyline around the top of the stake like usual and then feed the guyline through the hole at the bottom before connecting it to my tent/tarp. This allows the anchor point to pull from the bottom of the stake rather then from the top helping to keep the stake in the ground where it belongs.

Now if I can find a company to cut the stakes. Anyone?

Any and all feedback would be greatly appreciated.

[Bob Gross]

By putting the lower center hole right along the V-bend line, you make a weak spot in the bend if you are pounding it into hard soil. The hole doesn't need to be in the center. It could be off to either side, off the V-bend line. I made my own aluminum deadmen once and found this out.

–B.G.–

[peter vacco]

he's quite correct, that's a major weakening hole right there, and it's in what is about the "sweet spot" of places it really doesn't want to be.
but go ahead and drill some there, then, if your stakes don't collapse .. they're too heavy. so that's a thought …

bob's side hole is going to be probably the least destructive, and unfortunately looks wise, the ugliest solution.

hilleberg's come with a plethora of stakes. you've never dream they could send so many. or that you'd even want them.

if the shape was evenly tapered, they could be sheared quite effectively. left, and then right, using a simple jig
you can press brake the bend into them.
i had to heat to red my titi spoons to get them to bend sharp at the ends without cracking.

[Bob Gross]

Thank you for that comment, Peter, especially since you were the forum member that sent me commercial spam earlier today as a personal message. Thanks, but no thanks. Take your crap elsewhere please.

–B.G.–

[Adam Kramer]

i would love to see a glow in the dark tent stake

[peter vacco]

on further thought ..

maybe, if you're going to bend them anyway, it would cost the same effort to form them into sort of a semi circle. you might pick up a bit more stiffness that way. think of it as a larger the radius to the bend, it really does not have to be a totally exact circular shape.

cheers,
peter v.

[Jacob D]

Hi Lawson.

Bob's point about hole placement is valid, however if you can beef up the stake a little and keep it at or around 10g I think you are still doing good, if not perhaps an off center hole in a UL stake would be a winner.

My concern is that the force is acting at the narrow end of the stake. There is at least one similar product that solves that issue (so tread carefully in that respect) but this would still be better than using a traditional stake in sand/snow. I was at the beach this weekend with some 12" Easton stakes… luckily there was not much wind :)

Finding a shop to cut them shouldn't be difficult. Just look for local machine shops and fabrication shops and ask if they have a water jet, laser cutter, or CNC mill. You could probably even plasma cut these and have a decent enough edge. Breaking them will probably be the challenge since they're Ti and need a sharp break with very little edge to hold onto.

Looking forward to seeing what you come up with.

[Steven McAllister]

I find I sometimes lay my stakes sideways and pile rocks on top.
Holes or groves somewhere in the middle of the stake comes in handy for this.

Two off center holes or some notches on either side works and doesn't have the same issues as a hole along the bend.

I like the idea of the curved bend as opposed to the V bend.

One argument that people have had with the V titanium stakes in the past is that the thin metal can tend to cut through tie-lines in whipping wind.

Lets put our think-caps on about that issue.

[Steven McAllister]

I have liked these in medium loose rocky soil.
The slots/holes allow for many tie points, add gripping power and reduce weight, but I bet they add to the manufacturing cost:

Stakes with holes punched in them

[Lawson Kline]

I have to disagree about the placement of the bottom hole. The hole is only 1/8" in diameter and is placed in the strongest part of the stake down the spine. If the hole was placed off to one side, it would cause the design not to work properly.

As I said above, I drilled a center bottom hole in a set of V stakes several years back and have been using them ever sinse with no issues what so ever. The pros of the hole far outweigh the cons..

As you can tell, I am pretty set on the hole and know it works so I am looking for feedback regarding size and shape. Do you like the tapered design better then the more conventional straight sided design?

Thanks.

[Mark Ries]

Is there a way to make the wide part of the V towards the tent rather than the sharp part of the V I think this would make a V stake as effective as a Y stake as the point of the V will "plow" through the soil easier than the wide part of the V

[Mark Ries]

Are not you weakening the strongest point of the stake by drilling it there I would think that right beside the corner would be much better but then I cant even spell engineer… or can I, I dont know

[Larry De La Briandais]

I would think that your tapered design would hold at least as well as the straight design, if not better. And, it should be lighter. Sounds like a better design to me.

[Steven McAllister]

And being a little wider at the top makes sense as the ground is usually less dense near the surface.

[Eric Blumensaadt]

I checked out the GG ti stakes. Pretty impressive in design and weight. At 0.4 oz. they are even lighter than my MSR Groundhog stakes at 0.6 oz. each.

So, if your stake design is better at holding with its tapered design, which seems like it would be, then you may have begun a new cottage industry.

What's next? Maybe a ti stake "fire grill" with 6 or your stakes supporting 3 longish shepherd's crook ti stakes running thru your stake's top holes (minus the pull cords, of course).

[Ultra Magnus]

These debates intrigue me and since I'm at work with some simple FEA tools at hand I modeled up the stake as best I could by scaling the picture and ran the numbers, no hole, centered hole, and offset hole. Obviously, no hole is the strongest, offset hole comes in 2nd, and the centered hole is the weakest, but that is only taking buckling strength into account, and nothing else. With the hole offset like that, and the guyline through it in the way the OP wants it run, the offset hole would apply a twisting moment onto the stake, and that could loosen its grip in the soil, I would assume. If anyone is a civil engineer with experience in anchoring things in dirt, feel free to comment.

Since pictures are worth a thousand words –
https://lh5.googleusercontent.com/-SkQYkdELdq8/TkLoKjxIbNI/AAAAAAAABF0/usz4M4oxZyE/s1280/stake%25252C%252520hole%252520in%252520center.PNG

https://lh6.googleusercontent.com/-ry8cek7-rIw/TkLoLSsuZcI/AAAAAAAABFg/xK20RAx3Es0/s1280/stake%25252C%252520hole%252520offset.PNG

https://lh5.googleusercontent.com/-EcT8WoF0Nvw/TkLoLKnGMuI/AAAAAAAABFc/wgfENfrbX30/s1280/stake%25252C%252520no%252520hole.PNG

And for the record, I put a 100lb compressive load on the stake for my simulations, and that only loaded the weakest stake to 1/4th is rated tensile strength. Also, I had to make it .022" thick to make it weigh ~7.6 grams @ aprox. 0.150 lbs/in^2, 6Al-4V titanium.

BM

[Mark Ries]

Two offset holes would take out the twisting and I bet would still be stronger than one in the center

[Lawson Kline]

Wow. Thanks a ton for doing the stress analyse on this for me. BPL members never seize to amaze me.

Is there any way to tell if the stakes would be stronger with the more conventional straight sides or tapered like I have them?

Thanks again

[Mark Ries]

The radius idea is great as I noticed sixmoons has out right now. I have some old walrus stakes like this great holding power but not the best head to pound on

[Ultra Magnus]

Good bet! Two holes is stronger than one in center, by about a 7ksi.

The traditional stake gave me inconclusive resutls. Keep in mind FEA programs are pretty stupid. Garbage in, garbage out. And this "simulation express" package is of the stupidest of all FEA packages (comes preinstalled in SolidWorks to get you to want to pay the $5k for the full boogie woogie package). All the FEA program now sees is the increase in stress across the notches at the top of the peg, and is showing that it's actually almost as weak as the one center hole, tapered peg, which we all know cannot be true. It's just that with the tapered peg, the stress was more evenly distributed through the whole peg, and not so concentrated in one location. This is an instance where further testing would be required before drawing any solid conclusions.

Also, the FEA can't take into account the fact that as the stake is driven further into the ground, the part in the ground is supported laterally by the dirt and won't buckle, so maybe at that point when it's more than half way in, the stress concentration at the notches gets worse.

https://lh6.googleusercontent.com/-MNyRMi-UbQA/TkMCsvhsMsI/AAAAAAAABGA/qpGfEg49FAQ/s1280/stake%25252C%252520traditional.PNG

https://lh4.googleusercontent.com/-Wu3B7HyUZj4/TkMCu-tBfAI/AAAAAAAABGE/4bP1nSCvzVY/s1280/stake%25252C%252520two%252520holes.PNG

BM

[Lawson Kline]

You guys are really making me think about this hole haha.

I am set on the centered hole but, I wonder the strength difference between a bottom centered hole vs one/two off centered holes once the stake is in the ground. If you use the stake in sand mode and feed the guyline through the bottom hole, the direction of the force would be perpendicular to the stake which changes everything. I am willing to bet the center hole would be stronger and less likely to deform then an off centered hole once in the ground. Just some food for thought..

[Jacob D]

The hole thing is what it is, Magnus' analysis illustrates it and Lawson, you explained exactly why it will weaken the stake – it's a hole punched through the strongest point. That becomes the buckling point.

In all likelihood it will never matter though as these stakes are intended for use in sand/loose soil/snow, correct? So, probably a moot point. However if someone was all-purposing them in hard/rocky soil a blow with a rock or mallet could potentially buckle the stake since the impact forces will be much higher than a load which is gradually applied.

Anywhoo… the wider stake will be stronger but not by much. The wider stake will have better pull-out resistance which is obviously desirable. Have you seen the toughstakes? http://www.toughstake.com

[Ultra Magnus]

And in my opinion as having worked several years in the metal fabrication business, laser cutting is the only choice for a part like that. Plasma is too sloppy, and water jet is best suited for thick chunks of non-ferrous metals (but I only have limited experience with water jet cutting). Laser is extremely fast on materials this thin, very accurate, and depending on your laser operator, produces very clean edges. Focusing the beam and getting all the parameters set right to get good clean cuts is a bit of a dark art in the fab shop.

I spent a fair amount of time on the blue collar side of the industry, and also on the white collar. My last job in a job shop was as the CNC turret punch press and CNC laser programmer. The shop I worked at had two 4kw lasers that cut everything from 30 gauge sheet to 1" thick. Very impressive machines (just slow in the 1" stuff compared to a plasma).

BM

[Lawson Kline]

Wow. Thanks again.. So my tapered stake with a hole is stronger then a straight stake without a hole. That seals the deal right there..

[Mark Ries]

yeah and then the hole can go back in the center cause it will not be on the bend

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