ridnharley
Well-Known Member
I've burnt some holes in my parachute protector, so it is time for dog barf.
What is everyone using?
Thanks.
What is everyone using?
Thanks.
What's the best dog barf to use?
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o1d_dude
'I battle gravity'
Whatever the big box stores sell.
A bale will last you a lifetime unless you use it for blow-in insulation.
On the plus side, it’s really cheap.
A bale will last you a lifetime unless you use it for blow-in insulation.
On the plus side, it’s really cheap.
icyclops
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The cellulose blow-in insulation they sell at hardware stores. I save the small netting that small potatoes, and other fruits and veggies come in and put the insulation in the net first And tie it closed. It helps prevent the insulation from shooting to the sides and burning the center of your chute. Just don’t overpak it. More of a problem with wider diameter body tubes no doubt.
Corning pink, heat resistant. Left over from a project.
Eric
Well-Known Member
Fiberglass ?!? Bad choice IMO. If I saw someone prepping with it I'd offer to substitute some of my cellulose like what Eric shows in post #5. Or after the fact I would "encourage" them to go pick it all up. We like our flying field and the landowners cows don't like pink !
Best dog barf to use is the kind you get at a launch from someone who's trying desperately to use up their bale. 
That is a terrible choice, and will create nasty litter on the launch site. One of the primary advantages of dog barf is that it biodegrades quickly.
bobby_hamill
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Just don't use the fresh organic type 
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I think most experienced folks here agree that one should *not* use fiberglass insulation. It’s harmful to people and animals, and never goes away. Property owners really don’t appreciate us leaving (harmful) trash on the field, which fiberglass will become. The whole point of using cellulose insulation is that it’s relatively harmless, very cheap, fire resistant, and disintegrates naturally.
[edit: whoops - apparently I hadn’t refreshed the page to see more recent posts]
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Check with the hardware store manager to see if they have any ripped bales. Happens sometimes during shipping. You may get a discount.
rharshberger
Well-Known Member
Cellulose blow in insulation Green Fiber as posted earlier is one brand typically carried by both Lowes and HomeDepot, Insulmax is a brand sold by Menard's (internet search only, as Menard's is not around here), Cocoon brand is another I saw while doing a search via the internet. Be careful as most familiar name brands of blow in insulation are fiberglass like Johns Manville and Owens Corning though they may offer cellulose varieties.
I used fiberglass when I was in grade school in the 1960’s. Had to use a lot of talcum powder (Oh my, another carcinogen!) or the chutes would get stuck. Best bet in this day and age is the treated paper dog barf and a light weight nomex cloth protector. I’ve had the protector get burned significantly but the chute survives and just simply replace the protector. Next time, I put a little more dog barf in. Don’t need to use gobs of talcum powder anymore. Kurt
beeblebrox
8 C6-0, 12 D11-9, 20 D20-0, 20 E5-0, 3 Cinerocs
Dog barf simply is terrible and messy, burning powder still gets past it. Make flameproof wadding at home with thick toilet paper soaked in flameproofing chemicals: Water + Boric acid + Borax, or don't use any wadding at all...build a baffle in every rocket.
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The combination of wadding and blown cellulose is arguably better for LPR than either alone. I like a half square in the empty volume of the motor casing, a pinch or two, then another square or two to cup the chute bundle.
I’ve found this to be especially true for airframe sizes BT-60 (1.5 " diameter) and above.
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I got some of this to replace the pink insulation. Reminds me of belly button lint.
o1d_dude
'I battle gravity'
That’s the stuff many/most of us use.
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Best dog barf to use is the kind you get at a launch from someone who's trying desperately to use up their bale.
This. 10000000000% this. I've spent 5 YEARS using and giving away from my bale.......have only barely made a dent in the first 2 inches of it!
I'm afraid that I'm going to have to put the rest of it in my will......
You mean the stuff the lab just developed?Just don't use the fresh organic type
The stuff right out of the boxer?
I think that came from a poodle.....
After experimenting, I have also found this to be true. My Fat Boy, Executioner, and Little Joe 2 just had great flights without a scratch on the parachute by packing the bottom of the rocket and down into the forward end of the motor mount with dog barf, with five or six squares of tissue wadding neatly stacked on top of it. I tried it this way because the tissue alone wasn't doing the job.
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That's the proper technique. All too often folks want to pack the barf IN the tissue wadding as a plug or a piston, which instead has a tendency to act as a blast baffle and allow the gas to blow by around the edges and can prevent the burning BP ejection charge from being contained, subsequently allowing burning BP grains to potentially hit the parachute/recovery harness or blow around the tube and burn against the tube.
The way you have it, the burning grains are contained within the pressure dispersing barf, will continue to burn/convert to gas, and be shielded from the recovery gear. The tissue wadding above the barf tends to bow in the middle under pressure, making an effective gas plug/piston.
There is no such answer...if it is flame proof cellulose insulation....all the same....has to meet whatever building codse there is.
And Yes per what some people stated use insulation with sheet or two of wadding......I have had numerous time insulation still in the air frame...sometimes a burnt hole sometimes NOT. I will try installing wadding first then the dog barf in the air frame.......a poster stated the wadding helps push out the insulation (dog barf).
dr wogz
Fly caster
better than what comes out of a cat scan...
I knew someone many many years ago (Demolition job) who wandered off, then came back. He was noticeably uncomfortable after his return. Turns out he went to relieve himself, and found some pink insulation to 'clean up with'.. Oooh, ouch!! (Had he asked, we would have given him the roll from the tuck!!)
Off topic but cat-dog related:
In the hydrocarbon processing industry the eternal question is, is a cat cracker anything like a dog biscuit?
Back to your regularly scheduled thread.
In the hydrocarbon processing industry the eternal question is, is a cat cracker anything like a dog biscuit?
Back to your regularly scheduled thread.
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Say what you will. Back in the infancy of High Power, I witnessed a more experienced couple using *popcorn* in large diameter birds. Sonotube-sized birds needed a lot of dog barf. (Chute cannons are the way to go now.) They explained the charred puffs self extinguished coming down and the coyotes and smaller wildlife got a morsel or two to eat. I had to admire that.
I admit I can't imagine filling up sonotube (or equivalent) with dog barf. I always imagined there were other methods, although I don't fly anything that size so I never thought too hard about it. I guess that's a way to use up your bale.
Popcorn is a great idea if it works.
Popcorn is a great idea if it works.
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