Dog Barf

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Sartori42

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Quick question....

Is the cellulose insulation used as a parachute protector biodegradable? I want to be completely environmentally friendly....

Thanks.

Steven
 
Yes it is.

Basically it is chopped up newspaper, that's why the gray color.

It has been treated with a fire retardent.
 
Rgr. The treating with the flame retardant doesn't hinder its biodegradability?

I don't think it does, but even so it would be more environmentally friendly than burning debris catching a field or house on fire as it floated back to earth. :)
 
Rgr. The treating with the flame retardant doesn't hinder its biodegradability?

If it does, it will still break down much faster than the wadding sheets will.

Dog barf is a great method, and I use a lot of it (in my house and in my rockets), but an even better answer is reusable Nomex flame shields.

These work really well in all but the smallest rockets.

-Kevin
 
Trust me, from someone who has left a bunch out in the rain, its biodegradable. It breaks down rather quickly.
 
Yes, barf is biodegradable, and the flame retardant is mostly borate, which in most parts of the country is actually a fertilizer, as most soils are boron-deficient to some degree or other (as a micronutrient it's not particularly noticeable). SO actually you're doing the environment a favor by using dogbarf in your rockets...

I actually wish everyone would use dogbarf out here on the farm, but I understand why a lot of folks don't... I have a lot of Big E 'toilet paper' myself... LOL:) OL JR :)
 
Biggest problem I have with dog barf is that it doesn't really plug a large tube very well - I will usually use a sheet or two of tissue with it just to make sure it plugs the tube completely.
 
"an even better answer is reusable Nomex flame shields."

- I have these but noticed that they don't always make 100% contact around the surface of the inside of the BT. Could some of the hot particles get around the nomex sheets?

"Biggest problem I have with dog barf is that it doesn't really plug a large tube very well "

- Please define "large tube". Will dog barf work well in my Big Daddy 3" tube?

Thanks everyone....
 
Will dog barf work well in my Big Daddy 3" tube?

Yep, as long as you don't scrimp and put too little in the tube - I usually put about 3" worth (loosely packed) in my BD, and haven't had any problem with scortched chutes or tether, yet (20-25 flights on it, now).
 
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"an even better answer is reusable Nomex flame shields."

- I have these but noticed that they don't always make 100% contact around the surface of the inside of the BT. Could some of the hot particles get around the nomex sheets?

"Biggest problem I have with dog barf is that it doesn't really plug a large tube very well "

- Please define "large tube". Will dog barf work well in my Big Daddy 3" tube?

Thanks everyone....

Many folks use a little wadding in conjunction with the Nomex shields. I'd imagine you'll be fine as long as the 'chute is encapsulated.

For the Big Da-doo I use 1 or 2 sheets of Estes paper laid in flat as a barrier, then dog barf on top. About a 3/4 inch thick layer of barf. You almost run into problems because the tube is large, but not very long. My cone is usually sitting on top of the 'chute.

N
 
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I'm mentoring a TARC team that switched from dog barf to Nomex shields. The rocket is a 2.6" tube and a 9" flame shield completely encloses the parachute and shock cord. With 20 or so flights using the flame shield there is not a single singe mark on the parachute. That's much better than they were doing with dog barf.
 
The rocket is a 2.6" tube and a 9" flame shield completely encloses the parachute and shock cord.


That's about the right ratio 3 to 1. On a 4" tube I use a 12" protector with no issues.


Al
 
Quick question....

Is the cellulose insulation used as a parachute protector biodegradable? I want to be completely environmentally friendly....

Thanks.

Steven

On your new builds, put in an ejection baffle and ditch the wadding completely.
 
another alternative to FP wadding and Dog Barf are Teflon Tape permanent Wadding "Pom Pom"s. Attached to the shock line the same way as nomex sheets.

Plain old white plumbers Teflon tape is used in 1/2" or 3/4" wide. They take a little time to assemble (30- 1foot strips each) but generally out last the model that are installed in. and can be replaced if ever needed. After recovery simply shake out the Pom-pom and redust with TALC baby powder before restuffing back in the model.
I've used them extensively in sport flying models BT-5 to BT-70. Gererally you only need one for BT-5 thur BT-50 models 2 to 4 in models Bt-55 to Bt 70:)
I've been very happy with their performance, with them I've yet to melt or scorch a plastic or Nylon chute.

Teflon Wadding Pom-Pom-H_ 8pic page 128dpi_12-04.jpg
 
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another alternative to FP wadding and Dog Barf are Teflon Tape permanent Wadding "Pom Pom"s. Attached to the shock line the same way as nomex sheets.

Plain old white plumbers Teflon tape is used in 1/2" or 3/4" wide. They take a little time to assemble (30- 1foot strips each) but generally out last the model that are installed in. and can be replaced if ever needed. After recovery simply shake out the Pom-pom and redust with TALC baby powder before restuffing back in the model.
I've used them extensively in sport flying models BT-5 to BT-70. Gererally you only need one for BT-5 thur BT-50 models 2 to 4 in models Bt-55 to Bt 70:)
I've been very happy with their performance, with them I've yet to melt or scorch a plastic or Nylon chute.

Man, that is a good idea.
 
Yep, as long as you don't scrimp and put too little in the tube - I usually put about 3" worth (loosely packed) in my BD, and haven't had any problem with scortched chutes or tether, yet (20-25 flights on it, now).

I agree... I've noticed that a lot of folks that gripe about getting burned spots on their chutes with dogbarf (most not all) are usually not using enough... From my experience I'd say use enough barf to make a plug at least the thickness of the body tube diameter, (IE about a 2.6 inch long 'plug' of barf on a BT-80 rocket) but probably half again that isn't a bad idea (say about 3-4 inch plug of barf on a BT-80 rocket) if you really want to be sure you don't get scorched. Also I've noticed that 'packing' the barf a bit into 'plugs' seems to help on larger rockets-- leaving it fluffy lets it blow apart too much and particles to 'zip right through it'. Ya can't pack it like ramming a bullet down a muzzleloader rifle or it may not deploy, but a light 'tamping' once it's in the tube isn't a bad idea.

I like the ideas of nomex, baffles, and those micromeister pom-pom's are cool, but lets face it, most rockets still use wadding or barf. Personally I prefer barf because it's less messy (less I have to pick up while walking the pastures after a launch, but then the stuff I pick up I can reuse myself so it's not a total waste... LOL:)

Geez, I must be getting old... starting to sound like my grandmother, who, having lived through the Depression, used to REUSE TOILET PAPER!!! (No I'm not kidding!) :eek::eek:

Later! OL JR :)
 
Geez, I must be getting old... starting to sound like my grandmother, who, having lived through the Depression, used to REUSE TOILET PAPER!!! (No I'm not kidding!)
TMI, Luke, TMI!

Too Much Information
 
What I like to do with dog barf is two lay them down on top of the body tube and then push it down into the tube with a finger. Don't crumple it into a fluffy ball and insert it like that. One or two sheets is fine for me. Then I like to pile a bunch of dog barf on top of that. Maybe a couple hand fulls for a BT-60. More dog barf is a lot better than too little, so don't be afraid to put a lot in. Then after the dog barf is in, put one more sheet of wadding on top of the dog barf. It's worked fine for me and I've never had a singed chute using this method, even with the stronger charges from AP reloads.
 
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