Typical LPR Parachute thickness?

[vigilante]

Title says it. I'm just curious what the typical "mil" thickness of an Estes or Centuri LPR plastic parachute is.

[gpoehlein]

Easy enough to find out - I just mic'd an Estes 12" chute. Four layers measured .005", so that would make one layer equal to 1.25 mil (a mil is 1/1000 inch or .001 inch). Don't have any Centuri chutes around to check them, but they should also be in the 1 to 1.5 mil range.

Greg

[foamy]

I have an original Centuri chute from '69 that came (obviously) with my little Javelin. I'm no expert on polyethelene thickness and I don't have a micrometer, but I'd have to agree with gpoehlein. I did have to deal with various thickness-es of the stuff at a job I had many years ago and the parachute material is about as thin as it gets, if things haven't moved past my experience.

Quite a nice 'chute as plastic ones go. Hard and stiff red string for the shrouds and it was all tied up and ready to go when I took it out of the bag. Nice design on it too.

[tbzep]

At the opposite end of the spectrum in thickness is the old Quest chutes. The white plastic had yellow and red print. They were thick and very stiff. They needed a good dose of powder, last minute packing, and a virgin blood sacrifice to ensure complete opening at ejection.

[jharding58]

The average traditional garbage bag. Not the new fangled "less plastic" bag.

[vigilante]

The average traditional garbage bag. Not the new fangled "less plastic" bag.Thats kinda the direction I was going. I wanted to experiment with several "black" chutes to see how well they show up at higher altitudes. Looking at garbage bags at wally world I've noticed thickness's from .07 to 1.5 mil. Wasn't sure if the real thin stuff would hold up and not sure if the real thick stuff would open up. :)

Thanks all for the answers.

[gpoehlein]

Thats kinda the direction I was going. I wanted to experiment with several "black" chutes to see how well they show up at higher altitudes. Looking at garbage bags at wally world I've noticed thickness's from .07 to 1.5 mil. Wasn't sure if the real thin stuff would hold up and not sure if the real thick stuff would open up. :)

Thanks all for the answers.

I use .5 mil black garbage bags for competition chutes (thinnest I can find). They work fine - I've flown D dual eggloft duration using that garbage bag plastic in a 36" chute (with over the top shroud lines). It thermaled away and I lost sight of it at 14 minutes. I've yet to have one shred on me.

Greg

[vigilante]

Wow! Dual eggloft with the thin stuff 'eh? I shouldn't have a worry then. I wont be sending anything near that heavy up. I will go get a box of that .7 then. Very cool.

ps. What did you mean by "over the top shroud lines" ?

[bernomatic]

Wow! Dual eggloft with the thin stuff 'eh? I shouldn't have a worry then. I wont be sending anything near that heavy up. I will go get a box of that .7 then. Very cool.

ps. What did you mean by "over the top shroud lines" ?

Shroud lines that run over the material of the chute (thus actually forming a loop) as opposed to just from the corner of the chute to the attachment point

[vigilante]

Oh. I've never seen that. Very interesting.

[bernomatic]

Oh. I've never seen that. Very interesting.

Personally, unless your using a large parachute (over 24") I don't see the point in them as you're probably increasing the weight more by the additional shroudlines as opposed to the savings from the material thinness. IMHO/

[jharding58]

Yep, sometimes over the top is OTT.

[hcmbanjo]

Thats kinda the direction I was going. I wanted to experiment with several "black" chutes to see how well they show up at higher altitudes. Looking at garbage bags at wally world I've noticed thickness's from .07 to 1.5 mil. Wasn't sure if the real thin stuff would hold up and not sure if the real thick stuff would open up. :)

I've been using the WalMart black trash bag parachutes for a few years.
I've cut them out of the .9 mil and 1.2 mil thicknesses.

Being this dark, they show up fine in the sky. But being black, they can get warm when opened and might thermal easier than a white chute.

Mainly, these are extra chutes I keep in my launch box. For instance, I'll carry three 12" parachutes with different sized spill holes in them.
I tend to use what comes in the kits, but it's nice to have the garbage bag extras.

[tbzep]

If you want to use trash bag material, hit the clearance aisle next November and pick up all the orange Halloween garbage bags for next to nothing. They probably aren't a lot more visible than black against a bright sky, but orange looks cooler. ;)

BTW, for mid power, complete trash bag pumpkins can be used as chutes and are fun for demos around Halloween. The first time I saw a pumpkin recovery system was at Huntsville's Rocket City Classic back in the late 80's or early 90's. George Gassaway had a couple different orange pumpkin garbage bag chutes that day.

[gpoehlein]

I've tried the orange pumpkin bags and I found that the plastic was stretchier than most - the tape disks at the corners ripped out on that one and I've never had that problem with any other material. Funkiest material I ever used was some scented trash bags I picked up at Target - my parachutes were light pink and smelled like roses! :chuckle:

Yes, over-the-top shroud lines are pretty heavy and should only be used for egglofting events. All the rest of my competition chutes are attached at the corners with mylar tape (I found silvered mylar tape at Blicks, BTW). Even my 30" chutes I use for my parachute duration models (30mm diameter cardstock tube tapered down to either 13mm or 18mm minimum diameter cardstock tubing at the motor) use shrouds taped to the corner - I've never had a failure even with the .5 mil trash bags.

If you are looking for another source of parachutes, check out the Hartle Engineering chutes - they are a bit heavier plastic and are great for sport flying. Ed is Evil Ed here and on TRF. You can order the chutes from Uncle Mike's Rocket Shack:

http://www.unclemikesrocketshack.com/Hartle_Engineering/Hartle_Engineering.html

Uncle Mikes gives great service and Ed's chutes are a great middle step between plastic Estes chutes and nylon chutes (they are heavier, so aren't as good for competition, but for sport use they are top notch!). Give them a try.

Greg

[tbzep]

I've tried the orange pumpkin bags and I found that the plastic was stretchier than most - the tape disks at the corners ripped out on that one and I've never had that problem with any other material.
That's interesting. The ones we had several years ago and filled with leaves were not as tough as the usual black Hefty, but just as strong as any of those thinner scented white ones the wife sometimes buys.

[blackshire]

At the opposite end of the spectrum in thickness is the old Quest chutes. The white plastic had yellow and red print. They were thick and very stiff. They needed a good dose of powder, last minute packing, and a virgin blood sacrifice to ensure complete opening at ejection.*Sigh* Ah yes, Quest 'chutes... In my (mostly sad) experience with them, they don't open unless they are first so thoroughly crumpled-up that they look like an un-made bed! :-(