Chute protector placement

[4regt4]

I'm just putting the final touches on my shiny new North Coast Bounty Hunter. N.C. uses a somewhat unusual shock cord arrangement, as it's a steel cord from the motor mount to near the end of the body tube. Then there is elastic and Kevlar (much longer) in parallel for a belt-and-suspenders type backup, just in case.

I haven't used chute protectors before, and I'm wondering where to place it. 1. At the junction of the steel and Kevlar/elastic, which means that the bulk of the shock cord is in the protector, just under the chute itself. Or 2. Just under the chute, which means that the shock cord is not protected. However, it seems that doing this may reduce the risk of things getting tangled up in the chute protector upon deployment.

Thoughts?

Hans.

 

[bjphoenix]

If you had kevlar shock cord away from the end of the motor, it would not require much protection although it is always best to protect it somewhat for maximum lifespan. But with elastic too I would recommend protecting it.

 

[Tractionengines]

I would secure the protector a little ways out of the body tube. You want it to shield the cords and parachute during ejection, but then have that stuff in free air for actual deployment.

Check the steel cable on a regular basis. The corrosiveness of the BP charges will degrade it over time. Especially if not cleaned off. Wiping it down with a "baby wipe" the best you can will help.

 

[4regt4]

Yeah, OK. Seems I remember some advice from T. V. Milligan suggesting something similar - protector just clear of the body tube.

I'll find out the hard way next weekend. But I'm leaning toward your suggestion.

Thanks

Hans.

 

[4regt4]

Check the steel cable on a regular basis. The corrosiveness of the BP charges will degrade it over time. Especially if not cleaned off. Wiping it down with a "baby wipe" the best you can will help.

Any suggestions for cleaning or neutralizing the BP residue? I wonder if baking soda would help.

Hans.

 

[Tractionengines]

I mainly wanted to highlight that just because it's a steel cable, doesn't mean you can ignore it, or that it will last forever.

Like I said just wipe it off. I use a lot of baby wipes to clean up after a launch. They are not too wet to damage cardboard parts from a quick wipe. Also the "chemicals" seem to do well. I also blow any loose bits out with compressed air.

 

[4regt4]

One big problem I have with any of the baby wipes I've been around is the aroma. I'm quite allergic to it. I've seen some supposedly scent free ones, but still no-go. Have you found any that don't stink?

Hans.

 

[Tractionengines]

Just use any wipe you can. Or let it go completely, and just inspect it each flight day.

 

[bjphoenix]

Black powder residue can be easily cleaned with soap and water, but it has to be kept away from the body tubes. I don't know of any way to just neutralize it.

 

[Hobie1dog]

I would secure the protector a little ways out of the body tube. You want it to shield the cords and parachute during ejection, but then have that stuff in free air for actual deployment.

Check the steel cable on a regular basis. The corrosiveness of the BP charges will degrade it over time. Especially if not cleaned off. Wiping it down with a "baby wipe" the best you can will help.

this is what I will do in the future

 

[rcktnut]

I have an NCR Big Brute has a good 30-40 flights on it (one of my favorites) Never did a thing as far as cleaning the steel cable. I have the elastic cord (3/4 inch wide) tied directly to the steel cable with a 18 in. Nomex cord protector slid down to the forward centering ring over the steel cable and the shock cord. I don't use a chute protector at all just a few inches of dog barf. Stuff is dirty but I use dog barf in every rocket I fly, chute protector or not.
I've had holes in chutes just using the protector alone and have never had one since using the dog barf with the protectors.
As far as cleaning cardboard tubes of residue etc. I use a rag with 91% isopropyl alcohol. Never harmed a tube in 24 years.

 

[jmasterj]

One big problem I have with any of the baby wipes I've been around is the aroma. I'm quite allergic to it. I've seen some supposedly scent free ones, but still no-go. Have you found any that don't stink?

Hans.

The water-only style ones are useful in my experience.