Quantifying the ideal ‘mid

Pyramid shelters have become inexorably associated with modern “ultralight” backcountry travel.  For me they’re a staple, one I’ve discussed extensively (most recently and completely here), that for many conditions provides a light and simple no-thought solution to whatever weather might come along.  That said, I do think the utility of mids has been overstated.  Their chief virtue is a shape which deals well with both wind and precipitation without requiring too heavy a support structure.  Adding ventilation is at best problematic, and at worst a waste of time and weight.  Trips which don’t require exceptional weather shedding, and favor ventilation (often in concert with bug protection) are in the majority during the warmer six months of the year in Montana, and for an even greater period of time elsewhere.  Having the Tensegrity 2 (which is both sadly discontinued, and still available on clearance) in our quiver has been nice for those trips, and relieved much soggy, claustrophobic bugginess which in years past mids have provided as a mid-summer blessing.

What then makes for an ideal mid shelter?  If mids are good for snow and rain, and most especially for strong winds, it makes sense to maximize those attributes.  Design features which promote wind and snow shedding are worth the weight, anything else has at best a marginal case for existence.

But what are these features, and which attributes and dimensions make a ‘mid work best?

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My favorite mid features, or at least the simplest one to love, are the sod skirt and abundant ground level stake points on the Seek Outside BT2 (red shelter shown above, now slightly modified as the Silvertip).  Having a windy weather specialist that has a big gap along the hem to scope in wind and freeze the occupants has never made any sense to me, and was the sole reason I sold my MLD Trailstar many years ago, and a major reason I sold my MLD Solomid more recently.  The small sod skirt or snow flap arrangement on the BT2 solves this problem definitively.  Even a mid like the BD Megalight (above) which has fairly mild caternary curve along the bottom edges, still leaks a lot of wind unless you carry bury the gap in snow.  Today I find it hard to imagine why I’d ever want a mid without a bottom flap.

That the BT2 has 12 ground level stake points, closer than 3 feet together, both helps seal wind out and adds considerably to the overall pitch strength.  Mids resist wind, rain, and snow by having lots of tension between the apex (supported by the pole) and the hem, supported by stakes.  Unless you bought an Aliexpress special made from shit fabric, your mid will almost certainly fail in one of two ways: high winds and snow will snap your trekking pole, or will pull the stakes out.  The first problem can be addressed with burly trekking poles or a shelter specific pole, the latter by using the right stakes for the soil in question and by having a shelter which lets you use plenty of them.  Mid level guy points are useful, especially for minimizing panel deflection when design constraints put that area at risk, but ground level stake points are the foundation of a solid pitch, and of a solid design.  Square mids like the Megalight, which generally have nearly 9 foot sides and only one guy point at halfway could certainly do with two instead.  12 total for a mid of this size is emphatically not overkill.  The LBO pictured below has only 10, which makes for relatively big spans between stakes on the wider rear portion.  I wouldn’t object to an additional 4 in this spot.

R0023009R0000107R0012840Seek Outside LBO with 3 piece vestibule.  Hopefully these three photos, combined with the chart below, show the somewhat complex shape which I’ve found to perform so well in bad weather.

Sewing flaps and a bunch of guy loops on is easy.  So what about dimensions?   Specifically, what combination of height, length and width make for the strongest overall mid, while still maintaining useable space?

The chart below details a range of mids I’ve used a decent bit in the field, omitting the BT2 (which is no longer made) and including the Supermid (which I’ve never owned, but is something of a touchstone in the genre).  All of the listed dimensions have either been confirmed by me personally, or in the case of the Supermid taken from numbers Chris Wallace put in his BPL review a number of years ago.  My thesis before beginning this investigation was that lower angles would be characteristic of shelters which shed wind well, snow less well, and had less than ideal liveable space.  The Solomid and Cimarron fit into this category.  Higher angle walls would be characteristic of both good wind and good snow shedding, but would be associated with struggles getting stakes to stay put in looser soils, something I struggled with early this year with the SO 4 man tipi.

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As the numbers show, things are not so simple.  I was not surprised that the long wall of the Solomid was the lowest angle in the test.  I sold that shelter because it didn’t take much snow to put the wall down on my face.  I was a bit surprised that the long wall of the Cimarron was essentially the same angle, something which confirms my suspicion that this mid desperately needs to be 6+ inches taller, for both space and snow shedding purposes.  (It is worth noting that the specs for the LBO and especially Cimarron are deceptive, as these shelters are modified octagons rather than rectangles, and thus longer midpoint to midpoint than corner to corner.  I used the former figure as I think it tells more about bad weather performance.)  I was also surprised that the 4 man did not have steeper angles, and that the short axis of the LBO shares almost the same figure with both the Megalight and Supermid (53 degrees, also the wall angle of the BT2).

r0021562img_20874 man tipi, at top, with BT2 and Silvertip, below.

These numbers, and my experience of how they play out in the field, show that there is a tension between specific design elements when making a mid.  Steeper walls are better, within the realm of practicality.  They shed all weather better, and provide for more useable interior space.  Taking this approach too far adds weight, both in more canopy material and especially in a much heavier pole.  Modest winds broke a trekking pole used to pitch the 4 man this past winter, one that in the BT2 and LBO had weathered some of the worst weather I’ve ever witnessed.  I also suspect, but cannot quantify, that longer fabric spans require more staking power, and put more stress on even large and well placed stakes.  On that same trip I had a hard time getting the 4 man anchored well enough, in loose desert soil, to hold up to the canopy tension I wanted.  At the time I assumed it was due to a steeper wall angle, but that is obviously not the case, given that I’ve gotten every other shelter here discussed to work just fine in practically identical circumstances, and was using big premium stakes with the 4 man.

I suspect that making a mid much taller than 72 inches quickly runs into exponentially diminishing returns.

Another prominent issue is shape.  Circular mids, aka tipis like the 4 man and BT2, shed wind demonstrably better than square or rectangular mids.  The lack of long edges along the group also fights snow build up and wall collapse quite effectively.  The disadvantage is in pitch speed, with the time involved for the 4 man and something like the Megalight being 3-4 times greater, as well as in effective interior space.  The Silvertip, with its almost symmetrical hex shape, is a good compromise.  Such a shape allows the virtual box of occupied space to be longer than it is wide, without creating big flat panels to catch wind and snow.

IMG_2623IMG_3397The LBO after surviving the nastiest storm I’ve ever slept well through, the the Solomid after a night I spent only laying north to keep the wind out of my sleeping bag.

So if the dimensions of a good backpackable mid exist within a relatively narrow range, and the other major keys to success involve lots of stake points and appropriate fabric orientation when cut for the panels (an item for another day), what are the things which can be appropriately left off a good mid?  In short, almost everything else.  You need a door, but for shelters of this size I’ve concluded that two doors is a luxury I can do without.  For something like the LBO, for instance, I’d choose to go with a single end zip like the HMG Ultamid 2.  I would stay with the non-urethene #8 zips, and a good zipper flap with plenty of velcro to keep flapping to a minimum.  The massive vent formed by the beak of the LBO is the only one I’ve used which is remotely worth having, and I could easily manage without any vent at all.  Given that they’re all at least fairly fiddly to sew the cost savings involved is reason enough for vents to be left off mids.

A lot of the final weight savings on a mid ought to come down to appropriate materials selection.  Grosgrain ribbon for stake points, for instance, is more than strong enough.  5/8″ grosgrain is far stronger than even the very best 30D silnylon.  On the other hand proper webbing might be justified in this application for the enhanced abrasion resistance.  The material used to reinforce tieouts should also be carefully chosen.  Fabric weight much beyond that of the canopy itself is probably not necessary, and if the fabric chosen for the reinforcement stretches much less than the main fabric you might create one problem in the process of solving another.  Or just pull a Kifaru a tack that shit straight on to an extra wide rolled hem, because that is a really good idea.

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But what about condensation?  Plenty of conditions for which mids are ideally suited, such as sustained cool rain or deep snowy cold, breed severe condensation.  Venting has generally been the answer, but as discussed almost never works very well.  Condensation is worst when air movement is modest, and anything short of massive vents only work well when the wind is blowing to help them along.

The real answer is to have a solid fabric, breathable liner, as pictured above and discussed here.  I’ve kept the liner permanently attached to my LBO since I made it, and it helped keep condensation to a minimumon every hunting trip I took this fall, all of which had moderate to severe condensation potential.  6-8 ounces of liner is massively better than 1-2 ounces of vent, and can be left behind if desired.

The sad conclusion of all this?  No one makes what I want, so at some point this winter I’ll be doing what I promised myself I wouldn’t, ever; buying a bunch of sil and diving back into the slippery process of cutting and sewing precision curves.

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16 thoughts on “Quantifying the ideal ‘mid

  1. I really liked this post. I confess I know next to nothing about tents ⛺️ but perhaps now I know a bit more than next to nothing 😂 thanks 😊

  2. While I have never personally ripped a grosgrain stake loop I have been told from multiple sources that “how to not rip your stake out loops” was a topic of frequent and earnest discussion in the old days of the Kifaru forums, and as such have shied away. 1/2″ or even 3/8″ web is considerably more abrasion resistant for a weight gain measured in grams.

    Stakes used will of course be a large factor, if I could get away with round, smooth stakes all year GG wouldn’t scare me. Another factor is what tools you employ to break stakes free from frozen ground or snow, I’ve been guilty of being overzealous with a snow shovel more then once.

    1. Agreed, I wouldn’t use it for that reason. 1/2″ poly tubular webbing?

      1. My bias is for nylon, as flat and tightly woven as possible. Fate saw fit to bless me with a few rolls of 3/8″ web so that is likely what my next shelter would have.

  3. Timely article as I’ve been searching for a replacement for my Megalight. In theory I love it and in good weather when we’ve decided to pitch it, it has been great. But the second the wind starts to blow it’s fairly infuriating. Every pitch becomes something we need relationship counciling to get through and we always end up with three perfect sides and one that’s total shit.

    HMG mids are attractive for their no stretch instant taut pitch, but I don’t trust cuben and don’t have the $$$.

    The Silvertip is my current highest contender, and I would consider trying to get one with only one door.

    I’m sure there will be a post to come for your ideal MYOG mid, but what are the design features you’re looking for that aren’t found in anything currently on the market?

    1. I refrained from this subject here, because it is worthy of another 1500 words in its own right, and mostly because I need to understand it better. The following are my current thoughts.

      The Megalight should be a bomber mid, based on specs. I think the undoing is in the fabric and the panel orientation. Look at this photo (https://bedrockandparadox.com/2012/10/21/pimp-your-mid/#jp-carousel-6811), the mid panel seams are edge to edge so the corner seams have to be bias to bias, which means they stretch like crazy. Combine that with a less robust sil which stretches a lot and you just can’t get the darn thing as taut as you should be able to. MLD also does bias to bias corners (http://1.bp.blogspot.com/-K-kRlN9Rznc/UHuzZXlIqnI/AAAAAAAAOIU/o_sF1l0ng68/s1600/P1020728.JPG) but they use much better fabric and lack the mid panel seam. My presumption is that this allows for massive tension between the peak and the corner stakes which facilitates the trademark MLD drum tight pitch. SO does bias/edge on just about all of their seams, which allows for enough but not too much stretch.

      The Silvertip is a sweet shelter. The Supermid with the flaps they now offer would also be at the top of my list, but with the extra charge for the flaps it gets darn pricey.

      1. Thats basically my conclusion on the Megalight as well, I dont totally understand the bias-bias/bias-edge stuff but it all makes sense as to why i can never get the Mega to get as tight as ive been able to pitch an old Duomid.

        thanks for the response, hope we both find that mythical Mid soon

  4. The day will come when I need to replace my Dana Design Nuk Tuk (15+ years of faithful service). Your post has given me plenty to consider. Thank you.

    1. The Nuktuk looks like the original Chouinard pyramid; tall, with a ton of cat curve to the corner seams. You loose a bit of headroom that way, but holy cow is it quiet in the wind.

  5. I’m curious, do you have experience with the Titanium Goat Vertex 5? At 21 oz and at $255 seem competitive with other offerings. I like the conical shape, with the offset pole and the the mid panel guyouts, the location of the seams and the venting options.

    1. I’ve never seen a TiGoat shelter in person. By the numbers they seem like good options.

  6. I’ve been happy using a silvertip for two but I also think I could get by with one zipper/door I’ve used the trailstar for wind (don’t venture into snow) and it works fine until sand blows under :/ I think it makes a damn versatile canopy for summer shade/group cooking/lounging- so I think I will keep it

    I’ve been considering ordering an Oware 10×10 pyramid it seems like a decent dimension- bigger than the silvertip and with a 72” peak height, more space for up to four people to sleep or for a small group of 5/6 to commune in when it’s cold outside (I’m going on a group backpack with a couple of novice backpackers in February. I’m thinking the 10×10 will be more than enough for me and my gf to sleep in, while also allowing extra people in to stay out of the chill we will encounter lows in the teens )

    I know it’s a square pyramid so Wind shedding would not be as good but I have the trailstar/silvertip for that From your experience with mids close to 6 feet tall and 9-11 feet long/wide do you think it’s reasonable to fit a small group of people sitting inside or is this overly optimistic? Before I upgraded my BT2 to the silvertip I could squeeze 4 people inside the BT2 to play cards. I’m thinking the extra eight inches and 1 foot lengthwidth will create more space for a group of up to 6. Ideally we would find a tree to hang the apex from to free us from the center pole. The only other option is the Oware 11×11 but it seems overkill at 7.5 feet tall, something of a niche gear item I wouldn’t use too often for the weight and footprint needed.

    Thanks for your help Dave This was an excellent post

    1. The stats and features on the Oware mids look good. My enthusiasm was dampened after seeing one in person for the first time this summer; the main seams are rolled, rather than flat felled, and the general attention to detail seamed a bit spotty. That said I’ve never used a sil shelter without felled seams, so maybe that isn’t a big deal, but it was a big red flag.

      Having something as bomber in wind as the Trailstar with a massive gap at the hem doesn’t make sense to me, which is why I sold mine 5 years ago. If I still had it I’d put a skirt on it and see if that helped.

  7. Thanks for the great articles on Mids – very interesting though very frustrating at the same time.
    Did you meanwhile find anything that fits the needs, especially in terms of space and condensation?

    I’m looking for a new UL shelter for autumn/winter in the alps and so far I was looking at the Solomid or it’s XL variant and the Notch (I’m 184cm).
    Out of your experience, what would you recommend?

    1. My only gripe with the Solomid (I had the original) was the low ceiling, which exacerbated condensation problems. Performance in severe weather was impeccable otherwise. The xl looks very good.

      1. Thank you very much for the reply!

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