MYOG Tent Questions

Lance,
Will just share what I do – no guarantees.

(1) I put a flat felled seam in the wall wherever mesh or fabric will be attached to a wall. Purpose: to avoid an unreinforced seam along the wall that would probably leak due to the pressure of wind etc that enlarges stitch holes. You could place the seam high enough on the wall so it would meet the top of the 6″ high floor wall and hold it up. This should come close to long enough walls. If not, mesh can be placed between the floor and tent walls for ventilation, which would add to the height of the floor walls and place the seam in the tent walls higher, making longer tent walls. You might have to angle the floor walls inward to little to do this.

(2) The line in the diagrams where the mesh seems to meet the walls appears to be recessed from the leading edges of the walls. For the reasons stated above, you could add seams to reinforce the mesh to wall connection. But I would attach the mesh to the leading edges of the walls, since there are vestibules or end covers both front and back to shield the mesh. You would need to design a good seam arrangement for where the three materials, the mesh, the walls and the end covers, all come together. Look at tents on display for ideas.

(3) I use only one trekking pole, and don’t use them as supports, so can’t be helpful with this one, as I’ve spent no time studying the various joining techniques on T-pole supported tents.

(4) Yes that is the suggested way to install zippers on a curvature. I don’t do that either, as it places undue stress on the zipper, leading to zipper failure; so design only for straight zippers. Typically, this results in an inverted T on the mesh door zipper which I also find much easier to use (and to make) – but a half T, or and L could be used if you don’t mind the smaller opening. There, two zips meet at the corner of the L.

(5) This picture appears to have what may be construction different from your diagrams. But for any guyout location, I would reinforce each and every one of the pieces that come together at the guyout point. Since I use nylon coated with PU on at least one side (usually sil on the other side), I can bond a quarter circle patch to each of the pieces coming together. So there is just a double thickness in each fabric at that point, and no additional sewing is required on the circular line of the patch – hence no stitch holes away from the perimeter of the patch; but rather, just where you would put the stitching anyway along the fabric edges.

It is hard to explain all this without numerous diagrams, but hope it is of some help.

What Sam said is good, let me add

1) I put a flat felled seam at the ridge. It’s strong. You can do a cat curve.

2) I’ve never sewn mesh. Just fold it over and sew to the wall? It won’t take a lot of load so not critical. Sewing a row of stitches to the main fabric will weaken that main fabric a little, but not too much. Maybe make sure and seal that to make sure water doesn’t leak inside.

3) The peak reinforcements are where the most load is. I’ve had a pole poke through before. I’d make the tent without reinforcement. Erect it. Take a circle of the same fabric and place it over the peak. Do some hand stitches to sew on the circle. Place one side of circle and sew a stitch. Pull on the circle at the opposite side to stretch it the same as the tent fabric and sew another stitch. etc, maybe 4 total. You have to put folds in the circle to make it conic shape to fit over the corner. Maybe repeat with a smaller circle, maybe with heavier fabric. Take the tent down and machine sew all around the edge of the circle, two rows total, the hand stitches have it placed properly. That’s what I do for pyramid tents.

4) Where is the zipper, on the ridge of the vestibule? I just draw a line on the fabric where I want the edge to be. Fold over and sew that to the zipper as close to the zipper teeth as possible. The edge of the fabric can actually overlap the zipper teeth a bit without snagging. Then sew one more row of stitches further away from the teeth, close to the edge of the zipper tape. I just run the zipper all the way up to the peak reinforcement, and cover the top of the zipper with the peak reinforcement circle.

I assume the ridge line will be along the grain of the fabric. And the edges will be at right angles and also along the grain. I would also have the grain of the fabric on the vestibule where it sews onto the side, good to have the two pieces of fabric match when it comes to grain of the fabric. That means where the two vestibule pieces sew together, it will be on the bias of the fabric (https://en.wikipedia.org/wiki/Grain_(textile) ) Where two sides that are on the bias meet, you want that to be a cat cut or the fabric flops (https://backpackinglight.com/forums/topic/tent-on-bias/) That would say the vestibule ridge should be a cat cut (from experience). That would say the main ridge does not have to be a cat cut (I’m speculating). It is possible to lay out a seam (like the main ridge) without cat, erect tent and see if it needs a cat cut, and if so, add it. Like I did in that thread. I’ve also done that on a vestibule ridge, except I had to rip out the zipper. Since you’re making it a cat cut, the ripped fabric will be cut off so it doesn’t matter that it has a bunch of holes in it.

If the vestibule ridge was along the grain of the fabric you don’t need a cat cut (from experience).

5) No idea. I like to eat steak : ) Too bad this website doesn’t let you edit spelling errors on the first post of a thread.

I really like that polyester fabric from ripstopbytheroll. 0.93 oz/yd2 including the silicone. Nylon fabric stretches after you set it up, especially if the temperature changes or it gets wet? So you have to go back and tighten the stake guylines. Or you wake up in the middle of the night with fabric flopping in your face.

Hopefully I can make sense here and not duplicate what Sam and Jerry have said. Forgive me if I get long-winded, as I have thought a lot about this kind of configuration and have way too much to say.

1)Flat-felled is what I like, and I try to orient the fold of the seam so that it sheds water rather than collecting it. Sew a sample seam in some scraps and ply with it and you will see what I mean. And this leads to :

2) If you can arrange the seam layout so that your mesh is sewed into the seam that you already need due to fabric width, that is ideal so that you have one less seam to seal. The question is, will that seam be far enough down the slope to suit the bathtub size? Maybe and maybe not, depending on your precise configuration. You give a dimension of 100” for length, but is that at the bottom of the fly? I would guess it is, since that’s longer than I would think you’d want for the floor, but I could be wrong. Your drawing shows the mesh running horizontally out to the edge of the fly from the top of the bathtub floor. Doing that may mean that the tub is suspended only on the long sides (door side and back) and the short sides  will tend to flop down, unless you can set up some tension along that short side at the top of the tub (your setup can have tension at eh edge of the mesh where it attaches to the fly, but cannot at the top edge of the tub unless you add a connection from top corner of tub to either bottom corner of fly or some point along the main roof/vestibule ridgeline – but that may not be possible if you do as suggested by Sam and relocate the mesh top of wall attachment to that seam. The other approach is to have all edges of the tub supported by having your end mesh come down vertically from where it attaches to the roof – that allows it to support the edge of the floor tub, and may be helpful in terms of where your roof seam is located due to fabric width. I realize that ins some situations condensation running down the roof can meet the vertical mesh and run down it so that it is now inside the tub, rather than running toe horizontal mesh where it should drip through. So that is a point worth considering, and I have thought that some sort of tensioning setup – say a couple vertical shock cord connections – that hold up the edge of the tub, while mesh runs out horizontally or even downward to its attachment with the fly, might be the way to go. But more complex of course.

As to the actual stitching of the mesh – it can be a bear because it is stretchy, especially on the bias, so holding it in position is the hard part. The mesh does not tend to unravel in my experience, so seam detail are not very important – even just a single line of stitching often exceeds the strength of the mesh, so fancy stuff is not necessary. Taping the mesh into position may be useful, if masking tape will stick to your fabric – finding tape that sticks to silpoly well enough is not easy. Pins I like to avoid with waterproof fabric, since they obviously leave holes that you then need to seal; but since you are probably sealing the seam anyway that may not be such a big deal.

3) I think Jerry’s peak reinforcement plan is spot on, with the caveat that if you have mesh wall coming in at the seam that leads to the peak it gets more complex. If that is the configuration you end up with I would consider not sewing the mesh for the last 6inches or so up to the peak in order to leave room to do the peak reinforcement. Than you could just glue that last bit of mesh with your seam sealer, or throw in a few stitches thru the reinforcing cone that will also hold the mesh away from the peak to keep it out of conflict with the pole.

4) What you’ve heard for the curved zipper on the mesh sounds like the way to do it. Trying to get alignment any other way is sure to fail. Of course you can go Sam’s way and avoid the curve, but it’s still tricky to get alignment with a zipper in mesh, and if you like the arched door, as I do, go for it. When you cut the mesh, try to cut right along the center of the zip, and then you can fold back the mesh at your original line of stitching and topstitch it out of the way so it won’t snag.

5) Sounds like what you mean is not so much reinforcement as effectively small guylines for the bathtub. This is feasible but tricky to get right – all the angles of the lines have to be right so that all can be in tension, and all the lines should be shockcord in order to have some flexibility to accommodate variations on pitching. I think I would avoid all of this and just let the floor hang loose from its top edge, but I would make efforts to achieve some tension at the top edge (see #1 above) so that the top of the tub stays well off the ground. Yes it looks a bit sloppy to have the floor hang loose, but it is functional.

If I was going to try to get the tension ideas to work on the bathtub corners as you suggest, that photo is not much use, because as Sam has pointed out, that’s a rather different configuration that what you envision. And I would recommend that you add some stiffeners to the corners, vertical rods of something very light and skinny – carbon maybe? – right in the tub corners from bottom of tub to top – since that would help make it work by having a compression element . But again, I do not recommend that approach in the first place – just saying if you do try it, that might help.

On a more general note, I will have to respectfully disagree with Jerry regarding catenary cut – I think you want it on all edges of all panels of the tent for the best, tightest pitch, regardless of whether the seams are with the grain or on the bias. But I heartily agree that where you can you should join grain to grain or bias to bias for best results. I know that’s not always possible but it’s worth aiming for in general.

If you can get some cheap fabric and make a half size model of this thing you will learn a lot. Every tent I have sewn would have been much better on the second try, as I always find things that don’t work quite as I expected them to. Drawings are great but they do not show where the tension is and where it needs to be to make the tent work.

Another thing you can do is the mock up the entire configuration with string, the string being only the ridgelines of course. This could be very helpful with sorting out your floor to roof connections.

My experiment with laying pyramid tent on the bias is what leads me to the idea you only need cat curves on edges that go along the bias, not on edges that go along the grain.

I started with no cat curves and observed that those edges along bias need cat curves.

I don’t like to have any more cat curve than necessary because it reduces head room inside the tent.

You can make the tent without cat curves, then erect tent and see how much deflection is needed on which edges, then add the cat curves, like I did in that thread.

I don’t mind getting conflicting advice on the internet.  It shows me what to look for and figure it out for myself in the end.  I did a half pyramid with a vestibule which is different than other configurations which might be different.

I’ve always assumed and done bias to bias or grain to grain.  I wonder what would happen if that was violated? : )

Thanks to everyone for their input on this topic. Taking the time to share your experiences is already helping me out.

Regarding the second question.. I think I’m going to just try to fold over the mesh and sew it directly to the tent wall. Ideally I could sew the mesh into the seam but with it being 18″ from the bottom of the wall, it just wouldn’t line up right. I’m really trying to keep the mesh either horizontal or slightly downward to capture any condensation. I’m planning on sealing everything anyways so Ill let you know how it turns out.

After reading Jerry’s input on the mesh walls. I think I will reconfigure it to line up with the seams of the vestibule. If nothing else, it will give me more interior space.

I’m not sure if Ill be able to accurately identify the grain to grain piece but I’ll look more into it (thanks Jerry for those links). I’m guessing it’s similar to how mesh is way more stretchy in one directly rather than the other.

Just to be clear

“along the grain” is either along the warp or weft.  I have never noticed any difference between warp and weft.

If you’re at about 45 degrees to that, on the bias, it stretches a lot more.

If you’re close to warp or weft it’s more like on the grain, if you’re close to 45 degrees it’s more like on the bias.  I’m just speculating because I try to be very close to the grain.

One more note sewing mesh.  I sometimes sew a thin (1 inch) strip of fabric over the edge of the mesh, then sew that to the tent.  It holds up really well that way

Great Idea Paul! I’m going to do that.

Jerry that clears it up for me. Thanks!

I glanced through the thread and didn’t see any recommendation for using Silpoly XL instead. Have you considered that? It should eliminate your extra seams. Also, the Xenon Wide from Dutchware is 3″ wider than RBTR so that may be more in line with what you’re needing.

https://dutchwaregear.com/product/xenon-sil-wide/

Yea I’ve purchased the XL before from RBTR. They didn’t have the color I was wanting. I figured if I’m going to do all this work, it better be exactly the colors I’m wanting. I’m wondering if they are phasing some of the XL poly out because most of it was also out of stock.

I might look at the Xenon next time. Having it be that wide would make it much easier.

Lance, re: “I think I’m going to just try to fold over the mesh and sew it directly to the tent wall.”

You say you are using the RBTR 1.1 oz sil/polyester, PU 4000, which weighs 1.4 oz/sq/yd, according to RBTR. That is a fairly beefy 20 Denier material compared to some lighter ones that people are using; however, does it make sense to use lap fell seams on one part of the fabric to assure water resistance, and then just sew thru it to attach mesh on another part? Especially with a single wall with no inner to catch drips. Sewing means a lot of needle holes that will expand under the tension of a taut canopy in the wind, and that is truer of polyester because it is less elastic than nylon. Won’t the mesh from the floor also put tension on the canopy as you move about inside the tent?

You also note a very light mesh, less than .7 oz/sq/yd, but don’t say whether it is polyester or nylon. Being fed up with polyester mesh that dissolves into holes almost before my eyes, I’ve vowed to use nylon mesh only, and eat the slight weight penalty.

Also please note that your photo at the end of your OP shows a corner that will need guy outs at the top and at the bottom of the corner. You can use a guy loop strung to an acetal ring around the peg to secure both corners with one peg, possibly with a short carbon strut sewn into the corner to keep the vertical corner edge from wrinkling or partially collapsing. But that lower corner at ground level needs to be secured somehow.

Just some thoughts.

This may be helpful visually, but there are also comments/questions posted that Dubber responded to, which may help with the technical questions you have.  https://youtu.be/5yxaVmW-Q1I

Ok I have another question regarding the fly..

Since my sil poly is approx. 58″ wide. I’ll need to sew a couple pieces together but I realized I have two options.

I could attach two pieces along the ridgeline, (58″ X 82″) which would go from vestibule to vestibule. Then I would need to attach an 18″ piece to each side (18″ X 82″) to make each wall approx. 75″ x 82″. This would leave me with 3 total seams on my tent fly.

OR

I could turn my fabric so I have a 58″ X 150 piece. Then attach two pieces of 12″ x 150″ on either side of that to reach each vestibule. This would leave me with two seams that run vertically.

I might be overthinking it. However this would give me one less seam overall. Would there be any downside of choosing the second option? Is it important to have a seam at the ridgeline or does it not matter?

If you have a cat curve at the ridgeline there has to be a seam there

If there’s a seam at the ridge, it’s less likely to leak.  Seams down the sides will have water flow across them from up higher.

Like Jerry sez, you will want a seam at the ridge anyway to get the cat action. Plus, the horizontal seam at 58 ( or 57 with seam allowance) down might be a good spot to put a side pullout – one that you might not use all the time but could be good for heavier weather, and putting it into a seam gives you nice reinforcement.