DIY Tarp Ridge line?

[jbryan]

Ok, I have been looking at various designs for my next tarp project. But had a question about the ridge line. On my last tarp that I made I gave the ridgeline a cat cut. This made for a very difficult time sewing it all together with the flat felled seem.
Does anyone else add a cat cut to their ridge line? Or was this a unnecessary step that I took?

[sclittlefield]

Just don't do both ridgeline and edges - that would be overkill.

I don't think the ridgeline catcut is necessary, at least, not for the style tarps I build. I don't know of any other hammock tarp builder that catcuts the ridgelines either. That should tell you something.

There are some smaller ground dweller tarps that have catcut ridgelines, and on that style it makes a lot of sense because you really want the edges to be straight cut.

[jbryan]

Maybe that is where I got my last design from - backpacking light or something similar.
If no one around here is making it with it, that will save me some grief while sewing it.

[BOB1520]

On the tarp That I made and future one that I will be making soon. Don't/ won't have a catcut RL. Honestly when you pitch the trap it will end up looking like it is. Especially if you install pull outs on the side of the tarp. I didn't initially install the pullouts but I did a couple months ago and I really like how it gives you more room inside. That reminds me that I have to get some pics of it with the pull outs on it.
So as Sclittlefield said just catcut the edges and leave the RL sraight. If you visit his website www.backwoodsdaydreamer.webs.com and look at some of his photos you will notice the the RL appears to be catcut, but it's not.

I hope this helps.

[GrizzlyAdams]

Just don't do both ridgeline and edges - that would be overkill.

I don't think the ridgeline catcut is necessary, at least, not for the style tarps I build. I don't know of any other hammock tarp builder that catcuts the ridgelines either. That should tell you something.

There are some smaller ground dweller tarps that have catcut ridgelines, and on that style it makes a lot of sense because you really want the edges to be straight cut.

a timely question for me, as I have a tarp project queued up.
I laid eyes on the Mountain Laurel Design hex tarp in cuben. I suspected it had a ridgeline cat cut, and I asked Ron directly if that was true. He confirmed this.

Whether I'll do it or not is another matter, but there is an existence proof that someone who sells tarps uses a cat-cut on the ridgeline of at least one tarp he makes.

[WV]

a timely question for me, as I have a tarp project queued up.
I laid eyes on the Mountain Laurel Design hex tarp in cuben. I suspected it had a ridgeline cat cut, and I asked Ron directly if that was true. He confirmed this.

Whether I'll do it or not is another matter, but there is an existence proof that someone who sells tarps uses a cat-cut on the ridgeline of at least one tarp he makes.

I've added ridgeline cat cuts to a couple of silnylon tarps I made, based on their appearance when hung below the ridgeline. Modifying an existing tarp didn't prove difficult, but I felt I could have used the fabric more economically if I had planned the ridge cat cut from the beginning. Having a catenary ridgeline with sil works for me because I don't vary the pitch angle much.

I'm sorry to hear that MLD uses a catenary with cuben, as I'm also about to make a cuben tarp, and I hoped that the lack of stretch would make a catenary unnecessary, especially with the tarp over a taut ridgeline. My experiments with 3M 9460 adhesive transfer tape for a G4-type pack and numerous stuff sacks have emboldened me - I plan to use taped seams for the tarp, with sewn reinforcements only at the ends of seams, thus guaranteeing () waterproofness. Given the length of the seams, I'd rather deal with straight lines than curves.

Side note - 3M says 9460 tape is preferred over 9485 (which has been suggested elsewhere), but they also say that the use of their "Primer 94" will improve the strength of both types. So far the only vendor I've found for Primer 94 is Uline, and they would order a case from 3M. The stuff has an 18 month shelf life, so I don't want 12 bottles of it.

[GrizzlyAdams]

WV, you raise a point that occurred to me in the various discussions about hanging a tarp under a ridgeline, or over it. To wit, if you hang the tarp over the ridgeline you lose whatever advantages you thought you had by using a cat-cut on the ridgeline.

I'm inclined to take a miss on the cat-cut ridgeline, in part because my preferred approach is to put tarp over a ridgeline....gives me the ridgeline inside, I hang stuff from it.

The MLD cuben tarp ridgeline is made by overlapping the two sides by 0.5 inches and running two lines of stitching. Then, both on top and underneath, 1" wide single-sided tape binds the two halves together and seals the stitching.

I've used both the double-sided and single sided tape that questoutfitters sells, and used them both in very high load contexts. They are solid. I have some double-sided stuff I got from sailrite that I'm a bit more cautious about. I'll have to look into the 3M tape you mention. Thanks for the pointer on that.

I've added ridgeline cat cuts to a couple of silnylon tarps I made, based on their appearance when hung below the ridgeline. Modifying an existing tarp didn't prove difficult, but I felt I could have used the fabric more economically if I had planned the ridge cat cut from the beginning. Having a catenary ridgeline with sil works for me because I don't vary the pitch angle much.

I'm sorry to hear that MLD uses a catenary with cuben, as I'm also about to make a cuben tarp, and I hoped that the lack of stretch would make a catenary unnecessary, especially with the tarp over a taut ridgeline. My experiments with 3M 9460 adhesive transfer tape for a G4-type pack and numerous stuff sacks have emboldened me - I plan to use taped seams for the tarp, with sewn reinforcements only at the ends of seams, thus guaranteeing () waterproofness. Given the length of the seams, I'd rather deal with straight lines than curves.

Side note - 3M says 9460 tape is preferred over 9485 (which has been suggested elsewhere), but they also say that the use of their "Primer 94" will improve the strength of both types. So far the only vendor I've found for Primer 94 is Uline, and they would order a case from 3M. The stuff has an 18 month shelf life, so I don't want 12 bottles of it.

[sclittlefield]

I laid eyes on the Mountain Laurel Design hex tarp in cuben. I suspected it had a ridgeline cat cut, and I asked Ron directly if that was true. He confirmed this.

Whether I'll do it or not is another matter, but there is an existence proof that someone who sells tarps uses a cat-cut on the ridgeline of at least one tarp he makes.

Thanks for getting that info Grizz.

This has been a good discussion. The "over the ridgeline" nullifying the effects of a cat-cut ridgeline thought settles it for me, especially for us hammockers.

That said, I suppose, if you know you won't hang it over a continuous ridgeline, I still think it could be a great way to do a DIY tarp. Smokehouse's tarp is really great with just the ridgeline cat-cut.