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Dale Wambaugh
(dwambaugh) - MLife

Locale: Pacific Northwest
Re: Heavier 1.2 or 1.4 mil polycryo available in bulk in USA? on 05/15/2013 17:34:22 MDT Print View

I wonder if the heat shrink stuff they use for winterizing boats will work?

Michael Ray
(topshot) - MLife

Locale: Midwest
Re: boat shrink wrap on 05/15/2013 19:55:15 MDT Print View

Interesting thought. Did a quick search and I'd say it wouldn't be practical.

"This film is a heavy duty shrink polyethylene available stock in BLUE, WHITE, or CLEAR in 6 MIL and 7 MIL, from 12 feet wide to 36 feet wide."

Quite thick so it will be heavy, polyethylene based so I'd bet it stretches more than polyolefin and it would be hard to find small quantities when rolls are 12' wide min. Not too expensive really. I saw a 14' x 150' roll for $147.

Pete Staehling
(staehpj1) - F
Preshrink? on 05/18/2013 10:01:15 MDT Print View

Are there any problems with Polycro shrinking in the hot sun? Do you need to preshrink it or anything??

Edited by staehpj1 on 05/18/2013 10:06:46 MDT.

jerry adams
(retiredjerry) - MLife

Locale: Oregon and Washington
Re: Preshrink? on 05/18/2013 10:18:48 MDT Print View

preshrink....

hmmm...

Make a tarp and then use hair dryer to shrink it. It would form catenary curve. Actually, maybe better than a catenary because it would take into account the reality of your particular tarp.

somebody try this : )

Michael Ray
(topshot) - MLife

Locale: Midwest
Re: Preshrink? on 05/18/2013 15:45:32 MDT Print View

No need to preshrink. It needs much hotter temp than sunlight to shrink.

Nathan Meyerson
(NathanMeyerson) - F - M

Locale: NW
polycro ridgelines on 05/19/2013 23:20:39 MDT Print View

I see from this post that most people have run a ridge line through the entire length of the tarp, rather than using ridge pull outs. Is there any concern of abrasion on the film from running an full ridgeline?

Hoping to get one of these made.

David Gardner
(GardnerOutdoorLD) - M

Locale: Northern California
Re: polycro ridgelines on 05/20/2013 12:24:32 MDT Print View

Nathan,

I have not had any problems with abrasion of the film from a ridge line cord.

David Gardner

Pete Staehling
(staehpj1) - F
Re: Re: polycro ridgelines on 05/20/2013 13:32:55 MDT Print View

>>"I have not had any problems with abrasion of the film from a ridge line cord."

I'd be curious if anyone had problems due to NOT using a ridge line? Not saying that is the case here, but I like to avoid weight added to avoid a problem that has never occurred.

Edited by staehpj1 on 05/20/2013 13:34:34 MDT.

Michael Ray
(topshot) - MLife

Locale: Midwest
Re: Re: Re: polycro ridgelines on 05/20/2013 13:58:07 MDT Print View

> I'd be curious if anyone had problems due to NOT using a ridge line?

Not yet, but I have always reinforced any ridgelines with tape as a precaution as I expect it would stretch some over time. I don't know if that would really be a problem or not.

David Gardner
(GardnerOutdoorLD) - M

Locale: Northern California
Re: Re: Re: polycro ridgelines on 05/20/2013 20:32:50 MDT Print View

> I'd be curious if anyone had problems due to NOT using a ridge line?

Pete, I would personally not use the tarp without a ridge line cord. The ridge line is subject to significant forces, especially tension. The one thing polycryo is vulnerable to is tearing, and for just a couple of grams (I use 1 mm 150 lb. dyneema cord) you can virtually eliminate that danger. Also, the ridge line cord, when properly constructed, takes all the stress off the tape-to-tarp connection at the ridge line. Plus, the ridge line cord holds the A-frame shape of the pitched tarp and keeps a nice taut pitch in side winds.

Nathan Meyerson
(NathanMeyerson) - F - M

Locale: NW
ride line and tarp-tarp connections on 05/20/2013 23:43:17 MDT Print View

David, in your experience are tarp-tape connections at the ridgeline necessary, in addition to a ridge line cord? Don't they fulfill redundant purposes?

David Gardner
(GardnerOutdoorLD) - M

Locale: Northern California
Re: ride line and tarp-tarp connections on 05/21/2013 12:27:11 MDT Print View

Nathan,

They are not redundant. If you just run a ridge line cord the tarp tends to move on the ridge line in winds and sag in the middle all the time. You can see this in the first picture in this thread. I actually run three cords for the ridge line. One between the tarp-tape connections at each end to nylon washers folded into the tape, then two separate cords at each end from the washers for tying out. Thus the center portion can be kept taught between the tarp-tape tie outs, and considerable tension can be put on the ridge line cord(s) without putting any significant tension on the tarp itself.

robert van putten
(Bawana) - F

Locale: Planet Bob
ridge line on 05/21/2013 12:48:36 MDT Print View

I just add washer-grommets right in the center of the tarp where I want the ridgeline to go, and pass a Loooong cord through 'em. The grommet goes through the tarp itself.

I use a long cord because I prefer to tie off to handy trees instead of stakes and sticks or poles. It is much faster, stronger and easier to pitch this way.

In use I tie off my ridgeline and sorta scoot the whole dang tarp back and forth to where I really want it, then stake out the edge cords to hold it in place.

center tie for ridgeline

One concern about doing it this way is water running down the ridgeline and dripping under the tarp in heavy rain. Short little bits of hanging string near the ridge grommet will catch and deflect these drips.

Edited by Bawana on 05/21/2013 12:50:35 MDT.

robert van putten
(Bawana) - F

Locale: Planet Bob
ridgeline chafe on 05/21/2013 13:01:33 MDT Print View

I still have one of my tarps set up in the woods near my home. It has suffered damage but not from the cords.
I've had trouble with both my duct tape tie-out and the double sided tape that comes with the window kits and used for hemming coming undone. Cold, snowy conditions take the "stick" right out of many adhesives.

no sticky left!

Because I'm not going to blow three times as much coin on special tape as I did the plastic sheeting itself, I've started using gorilla tape which holds better and isn't to expensive.

Can't get away without another polycro tarp picture....

Polycro winter camp! Extra big tarp set up lean-too fashion.

lean-too

Aaron Sorensen
(awsorensen) - MLife

Locale: South of Forester Pass
Polycryo Tarp on 07/13/2013 20:44:36 MDT Print View

Spent the day making a polycryo tarp from 2 large GG polycyro sheets.aaa

I just used the parts I had available.
bb


I did order the suggested nylon repair tape that worked like a charm.
It is nice and light and can be moved if it not placed correctly.cc

I wanted a 12" height at the center of each end but sometimes what works on paper doesn't work when it all come together.
I can either use 3 stakes in each end or use a 42" stick (plan on this most of the time). I'll need another stick in place where the trophy is.ddd

I still need to add a tie out to the center of the front entrance.
The front is just taped without cutting any excess what so ever.
The back-side is cut along the pole then taped. It didn't come out as strait as I wanted but it also had to follow a curve which was really hard to actually cut correctly.eee

I don't have my scale. No idea where it is. The 2 polycryo's weigh 7.3 ounces and the pole about 4.5.
I don't think I added any more than 2 ounces with everything done to it. so hopefully it will fall in under 13 ounces?ff

I also still need to add a few inner loops with gorilla tape in order to hold the pole in place so it will probably end up at 14 ounces, however, this tarp is HUGE.
40" high, 60" wide and the beak comes out another 25" or so.
There is probably a good 50 cubic feet of usable room under this tarp.
Less than 1 ounce per 4 square feet works for me.

I'll take more pictures once I get it set up outside.

Edited by awsorensen on 07/16/2013 19:32:37 MDT.

Aaron Sorensen
(awsorensen) - MLife

Locale: South of Forester Pass
Re: Polycryo Tarp first set up on 07/21/2013 21:01:54 MDT Print View

Finally got the tarp out and set up.
Of course as soon as I did, the dog thought it was play time and ran right through, breaking it in 4 different places.
I fixed it but will have to strengthen a few corners or replace some tape before it's done.

The only thing that needs to be fixed other than the above is the front beak needs about 3 inches (tapered) taken off each side from center.
I'll also need to use stakes on the corners instead of the pole or a stick.
This will tension each side much better than what you see in the pictures.sdf

There is plenty of room for 2 inside.
This is more for me and 2 dogs. I just hope they learn that clear doesn't mean you can walk through it.werder

I'll get the final weight up when I get hold of a scale.cf

Edited by awsorensen on 07/21/2013 21:03:07 MDT.

Michael Ray
(topshot) - MLife

Locale: Midwest
Re: Re: Polycryo Tarp first set up on 07/22/2013 09:53:21 MDT Print View

> Of course as soon as I did, the dog thought it was play time and ran right through, breaking it in 4 different places.

LOL. Our dog did the same when I had setup my first tarp prototype. Being LDPE, it may have been easier to repair the major tear. I still used it for several weeks worth of nights, including storms.

My latest tarp I wasn't as pleased with because the tape didn't seem to stick as well for some reason. I had to fix a couple corners that pulled off under tension after a while (using shockcord loops). Same LDPE and 3M 2120 tape I used before (but maybe I used less). Even the nylon sail repair tape didn't stick that well (I had used it first). I'll try again with longer pieces of tape next time.

Franco Darioli
(Franco) - M

Locale: Melbourne
Polycryo Tarp Tested! on 07/22/2013 16:24:02 MDT Print View

Aaron,
The first good wind gust will tear it apart.
Take a bivy with you as well.

Aaron Sorensen
(awsorensen) - MLife

Locale: South of Forester Pass
Re: Polycryo Tarp Tested! on 07/22/2013 16:34:11 MDT Print View

The only reason this doesn't look taunt at all is because I need to stake out the corner end pieces.
You just can't pull anything tight the way it is. As soon as you do pull a corner tight, it become very taunt.
I also have a lot of slack in the beak because it needs to have 3" taken off each side.

After all of this, I will not be afraid of wind gusts at all.

My dog got a running start and absolutely smashed into the tarp.
In the end, this will hold up to the wind. Maybe not 25+ gusts, but for 90% of my outings, it will be just fine.

Justin Baker
(justin_baker) - F

Locale: Santa Rosa, CA
Re: Re: Polycryo Tarp Tested! on 07/22/2013 17:21:57 MDT Print View

So it definitely won't hold up to a charging bear...
You should also be worried about the more likely event of a charging marmot. They can get pretty fat and aggressive.