Tarp Geometry Question

Not really.

There are a few lays that can translate from square to rectangle, but a set of lays you’d use (pyramid, hut, plow, etc) with a 10×10 are either wonky enough with an 8×10 that they don’t do their job (keeping weather out) or too hard to create with a few stakes and lines. I’d think about what sort of lays you’d like to try, and then get a tarp that works with those lays.

10×10 is a whole lot of tarp to manage in bad weather; a tarp is basically a sail in high winds. For your A-frame/lean-to/storm tube, I think an 8×10 is better, lighter and more manageable.

Mark, I dove into tarp life with an 8.5×8.5 tarp but I found that was tight when my kid came along with me and it was windy. More relevant: I realized that I really only used an A-Frame pitch. I also realized that a catenary cut tarp makes it much, much easier to get a tight A-frame with far fewer guylines.

Then I realized that it’s a pain to deal with the open foot and head when above treeline so I progressed to something more closed. I now use a Yama Mountain Gear Cirriform Min. I like how easy it is to get a drum-tight pitch and have 360° protection while also having the ability to open the front or side. In nice weather I don’t bother with the tarp if I can be under some trees to mitigate condensation but as soon as I want a tarp I like having a simple solution that provides full coverage.

YMMV.

Do you really need much more than A frame, or A frame with one end staked to the ground?

I guess my experience camping is that you either get rain with little wind that comes straight down, or rain with wind that might be predominantly from 1 direction, but never exclusively.

Are there really circumstances where these 2 pitches won’t work?

I haven’t spent a lot of time looking for complex tarp pitch videos where there was actual stormy conditions. It’s usually here’s how to do it on a nice day.

I tried various A frame pitches with 1 or 2 open ends.

I found that the wind can shift and start blowing from a different direction, or to be turbulent and blow from different directions

I just use a mid now – protection in all directions

Sorry if this is a little off topic, since OP seems to be set on using a tarp but wants advice on how to use it.

I tried a 10×10 tarp for a few trips. I ended up just cowboy camping all the time and if I did use it I would just roll it over me like a burrito wrap. Messing around with a tarp, especially in the wind and/or rain after a long day, is just not a fun thing to do, IMO.

The last time I used this setup I was on top of Marmot Pass in the Olympic mountains, burrito wrapped on a windy ridge. Woke up at 5am to a mountain goat coming in to lick salts off my face. Great way to wake up from deep sleep. Went back to sleep and woke up to hearing something in my camp again, thinking it was Mr. Goat, turned out I jumped out of bed to fight a giant black bear sniffing around my camp. I don’t mind chasing off wild animals, but waking up to them right in your face is just not a fun way to camp. LOL

An Altaplex tarp from Zpacks weighs around the same as a 10×10 tarp and is plenty versatile without all the hassles. If the trekking pole is long enough, and the pole jack is in use, the pole can be angled out into the vestibule to create enough room inside for 1 adult and a kid or dog. The Altaplex tarp offers a lot more floor space than the Altaplex tent. I own both.

@ Mark. I used an 8X10 tarp for two seasons.  The easiest way to visualize pitches is to cut a piece of paper to 8X10 and practice on a table.  I tried lean to, flying diamond, a half pyramid (by folding an end of the tarp inwards, etc but mostly used an A-frame.  If you need more ideas I could search for the site that had the diagrams I used.

With a flat tarp, if expecting wind or rain you need to take extra time to find a good spot, like next to a tree or a big rock.  And you need a bit of time to customize the pitch to the site and the expected location.  For long term flat tarp users, I think this ability to customize is what they like about flat tarps. But since I found myself using an A frame pitch most of the time,I just bought a Grace Solo Tarp from MLD.

For 3-season camping in the California coastal range or the Sierra Nevada, when expecting wind or rain, I just pitch it low and find I have pretty good protection.  I did buy an inner net tent. So if I expect worse weather, I bring the net tent for a shelter that weighs about 16 or 17 oz.  In winter, I use a MLD pyramid or pack the 4 season tent.

One thing I like about tarp camping is that I can pitch the tarp then go find a place to cowboy camp under the stars.  If it starts raining, I just move under the tarp.

Due to some horrible Scouting experiences, and the switching onshore/offshore winds in several places I like to camp, I want the ability to button up a tarp as much as possible from windblown rain, while still having the freedom to pitch it high for ventilation, etc.  I may be in the position of wanting a single tool to cover too many jobs.  I have a HMG Echo II, but find the “beak” for the wide end to be a little wonky.   That is probably why HLMG discontinued that model.  I like the concept of the above mentioned Yama catenary-cut tarp a lot.  They are sold out in DCF right now.  Figures.

I have the Ciriform Min in both DCF and Polyester. (I was torn on which one to purchase, went with DCF then a new polyester one showed up at a great price on Gear Swap). The weight difference is only a couple of ounces and the pack size is MUCH smaller with the poly Min. I’ve always know DCF was bulky but I haven’t ever had the same shelter in both materials before to compare how significant the difference is.

If I was going to sell one I might actually ditch the DCF version because of the pack size and it’s nice to have cheaper/less precious items. Also, I really value compact size in my pack. And it’s nice to be able to just stuff the tarp in a few seconds rather than folding it carefully.

My point is to not discount the Polyester version if you are considering this tarp. It has some very redeeming qualities.

Papa Hiker on YouTube has some of the clearest instructions on multi-geometry tarp pitching

https://youtube.com/playlist?list=PL8KMdG4VVjDck-KAqyj_nFbV5TbDmSPYx

At one time, I worked for a summer camp that wanted me to help them gear up for overnights.  The budget was short, so shelter had to be tarps, and figured out a set up that used the whole tarp and provided protection in all directions, without having to fold any fabric on itself; in other words, when pitched all of the tarp consisted of walls and beaks.  Unfortunately, can’t remember how it was done.  The tarps had to be square, or only slightly rectangular though, because that was all that was available then.

Everyone stayed dry under these tarps, but on one trip with a girls’ cabin, we were over-run by swarms of Daddy Longlegs, and the girls went nuts.  That was my first inkling that maybe something that could be totally buttoned up, called a “tent,” might be preferable, although stuck with tarps for years after that.

The photos in the video link in the original post suggest that some of the tarps have fabric folded under in order to achieve the desired shape.  That’s a waste of material, also heavy material in those days, and creates a possibility of water draining inside the folds.   A better course might be to model with some thin print paper as a rectangle, and  also with one end cut off to make a square.  And see what you can come up with.  Paper is cheap enough to try to model many different shapes.

Failing that, there are tons of shaped tarps out there that would do just as well to keep weight at its lowest, and also pack up easily if a ‘flat’ tarp, or close to it.   If you are going to use a bivy along with the tarp, one that has some extra overhead space at the head end incorporating netting, can help to protect from the bugs.  Some bivies certainly would have made a better experience for the girls, and a night’s sleep for me.

Matthew, do you notice much of a difference in wind between the silpoly and DCF Cirriform?

My 8 x 10 silpoly tarp gets a little flappy mid-panel even with the perimeter staked down taut. I suppose the smaller, cat cut panels of the Cirriform would lessen this billowing effect? But maybe not to the level of stiffness of the DCF?

I received the silpoly one recently and it’s only been set up in my yard. I haven’t had it in any wind yet.

Chris: I have Gen’s earlier version of the Cirriform, a 2P Terraform in sylnylon. I can tell you that with his deep cat cut geometry there is virtually zero   billowing even in heavy wind. I’ve slept in it during some pretty nasty weather and it’s just drum tight.  I often pitch it side to the wind and because the 2P has zippers on each side of the vestibule I can leave the downwind side open even in bad weather with little movement in the tarp.