How to get more width for a tarp....

[Rapt]

Or how to use narrower fabric and still gain something...

I was looking at dimensions and coverage and fabric widths and had a bit of an epiphany that while it involves more seams is also an efficient use of fabric and allows a greater effective width... Depending on the chosen dimensions the gains may be considerable. With the nominal BlackCat dimensions about 30" width per side could be achieved if you so wanted....

Here is an attached drawing showing how. Basically the parts you cut off for the taper of the hex at the ridgeline get sewn on the outer edges of the fabric. Piece 1 on the drawing, goes to the position shown. The tip (piece 2) may be used to fill the low point, again as shown. Repeat for all 4 corners...

Do the piecing then cut your curves. In my case I wanted a 14' ridgeline, and a 9' length at the 60" width fabric, but once I cat cut it my maximum effective covered width dropped from 10' to about 8'...

I LIKE BIG tarps (and I cannot lie... sorry flashing on MC Hammer ), so I wanted MORE... This gives me up to 24" more on each side... I chose a middle ground where the dotted line shows the tarp cut I'm planning. This increases my coverage by about 18" on each side at the points and I get more like 12' coverage...instead of 8'.... (in the flat..)....

Anyways.... Here's the PDF of the idea....

[Cannibal]

It appears to sacrifice coverage on the ends for the extra width. Is that correct?

You can call it the "OrigamiCat".

[Rapt]

It appears to sacrifice coverage on the ends for the extra width. Is that correct?

Not really....

If you use a "hex" design that's material you'd just throw aside as scrap. Instead you attach it to the edges... Like I mentioned with the BlackCat standard dimensions you cut off a triangle with a 34" base and a 66" height. This is material you could maybe use on another project, or to make a stuff sack, but it wasn't going on your tarp... Now it is.

There are already things that show a hex tarp has more coverage than a square for a given ridgeline length. Such as this photo by Blackbishop

In my case I wanted a 14' ridgeline, but to get a reasonable angle so I'd have a taut pitch I couldn't make the sides between the tie-outs much longer than 9'. That still gives more end coverage than a square. But the length difference meant I was cutting off a triangle 30" at the base by 60" high. This way I can add them to those sides and gain most of that back, instead of wasting it.

Giving me a tarp that can either be pitched wider and flatter with more area under it, or higher and narrower with better side coverage and headroom.

You can call it the "OrigamiCat".

I was wondering what to call it...

[Peter_pan]

Not really....

If you use a "hex" design that's material you'd just throw aside as scrap. Instead you attach it to the edges... Like I mentioned with the BlackCat standard dimensions you cut off a triangle with a 34" base and a 66" height. This is material you could maybe use on another project, or to make a stuff sack, but it wasn't going on your tarp... Now it is.

There are already things that show a hex tarp has more coverage than a square for a given ridgeline length. Such as this photo by Blackbishop

In my case I wanted a 14' ridgeline, but to get a reasonable angle so I'd have a taut pitch I couldn't make the sides between the tie-outs much longer than 9'. That still gives more end coverage than a square. But the length difference meant I was cutting off a triangle 30" at the base by 60" high. This way I can add them to those sides and gain most of that back, instead of wasting it.

Giving me a tarp that can either be pitched wider and flatter with more area under it, or higher and narrower with better side coverage and headroom.




I was wondering what to call it...

Note that this is a Black Cat which is some 30 percent larger than a MacCat...It is very close to a 12x10 that has been reshaped to provide a wide angle hex with cat edges. It is on the order of 100 sq ft and 16-18 oz or so.... It is compared here to an 8x8 with approximately 60 sq ft of coverage for 9 oz.

The unshown relationship is that the 8x8 is a actually the same or larger than a standard Mac Cat, just a slightly different shape . And that both the 8x8 and the MacCat are 30 percent larger than a standad BULA tarp.

All three tarps discussed here provide more than adequate coverage.... The real issue is, how much extra room would you like and at what cost in $ and weight.

FWIW, while we are on this point, it is fair to note that for any given size, the traditional rectange provides more coverage, more flexibility in pitch options and frequently weight LESS that the Cat Hexes because rectangles with rolled hems eliminate the weight of the gross grain tape commonly used to edge this design. They also are normally less costly.

Further, it is worth noting that the emerging rectangular tarps with mild cat cuts , like the Speer 8x10, may be the best of both worlds. Max coverage, less weight, more versatility, taut pitch and approximately equal cost for equivalent length sizes. So if you are into max coverage, taut pitch and less weight for a given ridge length consider these emergent cat rectangles.

Pan

[Take-a-knee]

What do you guys think of the Gosamer tarp?

http://www.gossamergear.com/cgi-bin/...inn-Twinn.html

It looks like it might be a bit short for a hammock at 117".

[Peter_pan]

What do you guys think of the Gosamer tarp?

http://www.gossamergear.com/cgi-bin/...inn-Twinn.html

It looks like it might be a bit short for a hammock at 117".

For the shorter hammocks HH BULA size, ENO , Travel pod, Byers and Claytor exped and mosquito it should be fine... taper on the foot end just means a little less side coverage, probably no big deal... little pricy though

Pan

[Cannibal]

I get it now, thanks!

Looking forward to pics of the final project.

[stoikurt]

How much more width are you trying to gain? The BlackCat already uses material that is 60" to 66" effectively giving you a 10'X12' tarp less the cat cuts. IMO it's a pretty big tarp already. Any bigger and it just gets heavier and cumbersome to handle.

[Rapt]

I'm limited by only having 60" fabric, but the idea would work with any width of fabric so it'd be possible to use 48" width say...

But personally mine is going to be 14' along the ridgeline and about 12' at the tie outs... Yes its larger than absolutely necessary, but 1) hate getting wet, 2) at times it'll be sheltering more than one person, 3) I want it to be absolutely bomb proof when it comes to rain...

So I'm not using all the potential gains. Just what I want to get from it...

I have 10 x12 tarps now and they never seem big enough.

[schrochem]

Interesting Rapt.
How much would you loose if you had the cat cut go just above the #2 pieces? I was just thinking that would be three less seams (per side) and still give a pretty darn wide tarp.