First tarp plans (pics) and a few inquiries!

[Kpi890]

Finally worked up the courage to make my first 1.1 oz silnylon tarp. The tarp will actually be for my girlfriends father who is doing part of the AT this year. He asked me if I would make him one after a long discussion I had with him about the forums here and how supportive and helpful everyone is. The newbie questions I have (because I've only made some stuff sacks and bags for fly fishing gear) may seem silly but I cannot seem to grasp my mind around some things still. Cutting silnylon in large lengths scares me! I have a rotary cutter that I like using it the most because it's simple and works very well with a metal straight edge as a guide. However, my rotary mat is only 24"x36" and obviously that is too small to be cutting a 9' tarp on. I really don't like the idea of cutting a little bit then moving the tarp on the mat and all that jazz. Below is an idea I came up (scrap ripstop shown).

Picture it on a larger scale. I have a piece of finished maple 1x4"that is 10' long and a piece of 1/8" aluminum that is 1" wide and 10 feet long. I will be laying out the fabric on a large area of hardwood floor and marking the lines for the measurements of the tarp. Then I will line the markings up under the aluminum and on top of the maple board and run the rotary cutter across the line to make one long, continuous, and straight cut edge. I also have a wood burning pen that has a sharp attachment for cutting, but wasn't sure if I really needed to do that. Let me know if you guys think this will work or if you have any other suggestions. I'm not too fond of my shaky hands sometimes to trust a 9' cut with scissors, but have never tried. The last question for now is about seam allowance. I think that if you have a 1" seam allowance you are accounting for 1" of your fabric to be take up in a seam (or roll hem)... Am I understanding that right? So say I have a finished piece I want to be 20" across but it will need rolled hem sides. Does that mean that i need to cut my fabric 22" to start and make sure my rolled hems take up one inch? I'm just a little stumped with the whole idea of seam allowance and do not want to cut this fabric the wrong size from the start. Thanks for your responses in advance! Suggestions always welcome!

[hikerdelita]

I am very interested your same questions as I am getting ready to cut my first silnylon. I also have a wood burning pen and rotary cutter. Which would be best? I'll keep reading.

I, too am planning to lay it out on a hardwood floor (attic space) to get plenty of room, and I have a clean sheet of thin plywood sub-floor I thought I could use as a smooth place to work, laying it on the floor rather than trying to put it up to table height. Haven't figured what my longest straight edge is yet. Your pic looks nice. Keep 'em coming and let us know how it goes.

hikerdelita
Sanford, North Carolina

[Kpi890]

I am very interested your same questions as I am getting ready to cut my first silnylon. I also have a wood burning pen and rotary cutter. Which would be best? I'll keep reading.

I, too am planning to lay it out on a hardwood floor (attic space) to get plenty of room, and I have a clean sheet of thin plywood sub-floor I thought I could use as a smooth place to work, laying it on the floor rather than trying to put it up to table height. Haven't figured what my longest straight edge is yet. Your pic looks nice. Keep 'em coming and let us know how it goes.

hikerdelita
Sanford, North Carolina

Then just piggy-back on this thread and we can both get some questions answered! Haha thanks!

[heycorb]

Sil doesn't fray that bad. I just draw my pattern and cut with some sharp scissors pushing the blade. Just take your time and you can get a close enough clean edge. Rotary cutters always give me inconsistent results. Scissors make it easier to cut on a curve too. I've tried using a burner but had mixed results. If I had one of those knives built for it, maybe not, but none of the cheap tricks worked all that great. If I did have a fray spot, a quick shot from a lighter did the trick. You will probably be roll hemming the edges any way.

[Kpi890]

Sil doesn't fray that bad. I just draw my pattern and cut with some sharp scissors pushing the blade. Just take your time and you can get a close enough clean edge. Rotary cutters always give me inconsistent results. Scissors make it easier to cut on a curve too. I've tried using a burner but had mixed results. If I had one of those knives built for it, maybe not, but none of the cheap tricks worked all that great. If I did have a fray spot, a quick shot from a lighter did the trick. You will probably be roll hemming the edges any way.

I've been trying to find a video of someone drawing out and cutting sil and cannot seem to find one anywhere.

[heycorb]

Just use a sharpie. I have a pair of razor shears that hardly take any effort to push through the sil. If you can tension he fabric down some it helps.

[Monkeyboy42]

I just need to ask, why is the tarp so small? Is he taking a 9' hammock, or ground dwelling?

[Kpi890]

I just need to ask, why is the tarp so small? Is he taking a 9' hammock, or ground dwelling?

This is more of a bivy shelter. Not for a hammock

[TPole]

I cut my tarp material by first folding it in half and then pinning it to a carpeted floor to hold it taught. It was easier for me to move the cutting mat underneath it knowing the fabric could not move. Also used some books near the cutting mat to hold everything down. You could use your long piece of aluminum as a guide that is left in place and then just slide the mat underneath.