Motor baffle system

[Scott Nokes]

Hello I've built a loc Black Brant 4 inch and I was wanting to ask with the baffle system in place, does that cut down the election pressure from the motor? Or will I still get good ejection power?
Thank you

 

[heada]

The baffle slows down the gases but it doesn't vent them so the pressure will be the same. You should see no difference in ejection except that the recovery device (parachute) is protected.

 

[Scott Nokes]

The baffle slows down the gases but it doesn't vent them so the pressure will be the same. You should see no difference in ejection except that the recovery device (parachute) is protected.

Hi there thank you for your advice and taking time to help me

 

[tfish]

I find that baffles that use stainless steel 'scrubbing pads' do reduce the amount of gasses produced. It still worth ground testing prior to flight.

Tony

 

[heada]

I find that baffles that use stainless steel 'scrubbing pads' do reduce the amount of gasses produced. It still worth ground testing prior to flight.

Tony

The LOC "dual-tube in a coupler" baffle doesn't seem to impact it for me. I'd love to hear if others have seen something different since that could change when I use them.

 

[Scott Nokes]

I find that baffles that use stainless steel 'scrubbing pads' do reduce the amount of gasses produced. It still worth ground testing prior to flight.

Tony

Thank you Tony

 

[Scott Nokes]

The LOC "dual-tube in a coupler" baffle doesn't seem to impact it for me. I'd love to hear if others have seen something different since that could change when I use them.

Thank you, I'll ground test and let you know the result.

 

[Scott Nokes]

Thank you guys, yes it's the dual tube Loc baffle system I have.

 

[Initiator001]

I find that baffles that use stainless steel 'scrubbing pads' do reduce the amount of gasses produced. It still worth ground testing prior to flight.

Tony

If someone builds two identical rockets except one has the stainless steel baffle and both are powered by the same type of rocket motor with the same amount of ejection charge how does the baffle reduce the amount of gasses produced?

It doesn't. The same amount of ejection charge gas is produced by the two same type rocket motors.

 

[Kelly]

how does the baffle reduce the amount of gasses produced?

Just making guesses, but it seems possible that the steel scrubber could cool the gases as they pass through, thus reducing the volume according to Charles' Law.
Regardless, I would never trust an ejection system without ground testing it.

 

[tfish]

If someone builds two identical rockets except one has the stainless steel baffle and both are powered by the same type of rocket motor with the same amount of ejection charge how does the baffle reduce the amount of gasses produced?

It doesn't. The same amount of ejection charge gas is produced by the two same type rocket motors.

I had been flying a 54mm min dia rocket..a dozen flights on it..or more. I had been using dog barf..to protect the harnes and chute. I ran out of dog barf..so I replaced the dog barf with a stainless steel scrubing pad. ..tied on to levlar shock cord. Used the same amount of BP for my apogee charge as I had been using...1 1/8 gram IIRC. flew the rocket and it came in hot..with no seperation...main was reefed with a line cutters. I actually found the rocket..the apogee charge had fired..and the cable cutter had fired too...only thing different on the flight was adding the stainless steel scrubbing pad...
The scrubbing pad cools the hot gasses...which makes me think it probably also reduces the amount of gass produced...I should have ground tested it before I flew it..and maybe up the charge a tad or so.
Just a heads up...
Tony

 

[Back_at_it]

The pressure is not reduced significantly. I'm a big fan of baffles and use them in a number of rockets. I will say that 4 inch is right where I begin using fire blankets instead of baffles as a 4 inch baffle does add a fair bit of weight. Not that it is really an issue with todays motors.

The only thing I will caution you on is to ensure that your baffle has sufficient flow. I have seen instances where the baffle was too restrictive and was either blown apart or caused the tube to burst below the baffle due to excessive pressures.

 

[Scott Nokes]

The pressure is not reduced significantly. I'm a big fan of baffles and use them in a number of rockets. I will say that the 4 inch is right where I begin using fire blankets instead of baffles as a 4 inch baffle does add a fair bit of weight. Not that it is really an issue with todays motors.

The only thing I will caution you on is to ensure that your baffle has sufficient flow. I have see instances where the baffle was too restrictive and was either blown apart or caused the tube to burst below the baffle due to excessive pressures.

Hi there thanks for your reply. I have the Loc baffle system that canned with my kit. Is that baffle ok

 

[Back_at_it]

Hi there thanks for your reply. I have the LOC Baffle system that canned with my kit. Is that baffle ok

Absolutely. I've used their baffles in a number of their rockets without issues. LOC tests their products before going into production. Great products and great people.

 

[Scott Nokes]

Absolutely. I've used their baffles in a number of their rockets without issues. LOC tests their products before going into production. Great products and great people.

Thanks, I agree, their kits are superb and the people are totally awesome.
They are the only kits I have ever built, other than a couple of those "The Launch Pad" kits.