Companion forum thread to:

MYOG: 3mil Plastic Tarps

Edited by addiebedford on 02/08/2011 21:56:38 MST.

Great article Jerry.

I have had great success with clear packing tape, usually 3M brand. I always have some around for shipping but have used it on a few pieces of gear. I used it to join closed sell foam together to make a koozie or insulator for my water bottle which I also use as a cup. The foam pealed off before the tape ever gave way.I have marked ounces and quarts on water bottles and playpus with a sharpie and then covered the writing so it would not rub off.

I have not tried it with polyethylene but bet it would work well. Could also use it to attach 2 pieces together and I bet is much lighter than duct tape.

Keep up the experimentation and good work.

Edited by hyperslug on 02/08/2011 15:43:57 MST.

Don't forget to recycle. Thanks Jerry.

I think the title should read "MYOG: 3mil Plastic Tarps." 3mm would be heavy duty indeed. :)

+1 on using mason's line for guy lines. I started with this stuff because I just had some around, but it's pretty strong.

Neat article. I've made similar tarps before. I agree the 3 mil is the perfect thickness, 2mm is a bit to fragile, 4mm too heavy. 3mm is a good balance.

You don't really need grommets for the corners, a sheetbend attachment is super secure and does not weaken the tarp corners or add weight. You can even eliminate the ridgeline grommets if you just run a line between two trees, though it's harder to get a tight pitch that way.

Edited by dag4643 on 02/08/2011 17:15:21 MST.

Just knowing someone would actually use poly for a tarp adds credibility to the idea. Nice!

A quick question: how, in your opinion, is using poly different than Tyvek? Both are light, and cheap.

Jerry, is good to see people are still thinking about how to do things inexpensively. One other option that would work for your guy lines instead of tape, pebbles, balls or grommets is to just tie a sheet bend knot with the plastic and line (a double sheet bend works even better). You get the total strength of the plastic and line and it can be placed right in the corner for a good tight pitch.

I started my scouts out with a piece of plastic and mason line and we use them for the whole summer. The boys re-used the plastic for ground cloths the next few years when the troop bought "real" tarps. I think some of them still are using the ground cloths. All in all the cost was minimal.

A Polyethylene tarp, a backpack made from a ForceFlex trash bag, a stove from a Budweiser can, and a sleeping bag from bubble wrap. And people will call you "trail trash"! :)

I just lost a few brain cells on that one.... ugh. LOL.

Edited by GeneH_BPL on 02/08/2011 18:52:22 MST.

Jerry,

On the silnylon version of your tarp with the catenary curves, are there 3 seams on the top section of silnylon?

In the picture the material seems to "gather" in the center of the footend of the tarp. It makes me think that there is a third seam.




Party On,

Newton

Edited to add picture for clarification of my question.

Edited by Newton on 02/08/2011 20:53:21 MST.

Thanks guys. This week is KILLING me! No more errors on my part, okay?

Okay. Now off to bed for me. Night all!
Addie

Hi Jerry

I haven't used PE sheet for an actual tent, but I have used rolls of it to make patterns for my tents.

Duct tape has a rubber adhesive, and this will creep. OK for quick repairs, but not for anything permanent.

Packaging tape comes in two varieties: cheap Chinese with a lousy adhesive which lets go, and expensive brand-name with a good adhesive. Brands like 3M, Husky, Nitto, Scotch should be fine. As it is a lot lighter than duct tape, try using a couple of layers.

However, really permanent-bonding anything to PE is hard to do without using really specialised adhesives which cost a LOT. Don't bother.

Cheers

Reinforced packing tape comes in a lot of varieties with different fibers, so I'd take a look around. I've used 1/2" wide no-name reinforced packing tape off the shelf of a convenient store as actual guylines to string up a sheet of plastic for a last-minute night outdoors, and they held up just fine. I imagine they'd be excellent reinforcements. Giving ridgelines a strip of tape and arranging it so that the tape (rather than the plastic) bears most of the load may provide even greater durability.

I know there is a heavy-duty transparent duct tape that is also useful for its UV resistance, but since it does have a rubber-based adhesive (similar to normal duct tape but more durable) it's probably less useful for projects involving poly (sticks great to mylar, though). Perhaps you can find a packing tape brand with extra UV resistance?

Would Gorilla tape have a place here?

Prototyping is definitely the way to go (at least until you're pretty competent at design and construction, and you have a pattern you're confident will work.

I prototyped the '5yds to UL' tarp using cheap nylon (£2/m vs £7-8/m for silnylon), documented here:
http://www.flickr.com/photos/andrewsleigh/sets/72157625981700212

I learned a huge amount, and I'm very happy I didn't use expensive fabric for my first version.

(I'm also envious of the access you Americans seem to have to light, cheap, technical fabrics!)

>Would Gorilla tape have a place here?


Gorilla tape hasn't slipped in my applications, but it is heavier than most duct tape. Good-quality packing tape sticks to plastic well, and is significantly lighter. I made pack straps from non-reinforced packing tape and stuck them onto a 40-pound bag of wood pellets, and they held fine (total weight of pellet-bag pack, after dumping the pellets: 2.1 oz; waterproof, too).

Also, the comments about using a sheet bend on the corners are right on: no need for tape or grommets, and tension is distributed through material better.

Edited by Otter on 02/09/2011 11:49:26 MST.

I've used 3m packing tape inside my dishwasher to seal off a vent which was steaming into our kitchen cabinets and affecting their finish. It's been in there for ten years. If you smell the adhesive when you apply it it smells like vinegar. To say it is water resistant is an understatement

My very first camping experience was when I was only four years old, circa 1964. My dad took my mom, my little brother and me camping along the coast of the Olympic Peninsula. We slept under a plastic sheet every night. I remember waking up to rain on Agate Beach and being amazed that we were dry - that was definitely "the moment" for me!

I agree with Tad, too; it's great to see you using inexpensive, readily available materials. I often wonder how many people never even try getting out because they just can't bear the idea of spending up to several hundred dollars on the gear that's "recommended" in some of the popular magazines.

Again, great article!

Reminds of my childhood camping with the old school tube tents!

In day glow orange not doubt!