How "cool" is the cooling mesh?

[blike]

I just built my first aerotech rocket, and I'm fascinated by the cooling mesh concept. Does anyone know how effective they are? I'm asking because I'm designing a video rocket, and I'm wondering how isolated the camera system needs to be. If the vapors are not hot, I'm thinking about just sealing the camera compartment with a bit of masking tape or something.

 

[Initiator001]

The cooling mesh system works well in BT-50 diameter and larger rockets.

I recall some tests we ran at Enertek/AeroTech using Estes plastic parachutes. As long as the plastic did not actually touch the mesh the parachute was fine.

I've used the cooling mesh in Estes kits that have flown on D12 motors. It does tend to expose the motor mount tube to sustained higher heat where the colling mesh is located so you may want to use a 'beefier' walled tube.

 

[RocketSmokEater]

i'm very intrigued by the term "cooling mesh"! i don't have any experience with Aerotech rockets nor have i built one yet - that will change soon! does anyone have a pic of this "cooling mesh" concept to check out? or at least an explanation? sounds very interesting!

RSE

 

[Ryan S.]

well what happens is you put this mesh (similiar to mesh used in some cleaning products, it is a mesh made of a bunch of metal that is curled up) at the top of the motor tube. At the bottom the thrust ring holds it up and at the top there is a baffly. The ejection charge goes off through this and it keeps the amount of fire down. It works really well

 

[teflonrocketry1]

Usually Chore Boy Stainless Steel Scouring Pads are used for this purpose visit:

http://rockets.puebloclub.org/reviews/#Aerotech_Mustang

http://www.reckittprofessional.com/find_a_product/products/chore_boy.html

Bruce S. Levison, NAR#69055

 

[Chr$]

By all means, Seal that camera in it's own chamber in the payload section. Exhaust gasses will corrode the electronics in a hurry. just take a look at your blast deflector and you'll agree.

 

[Lee Reep]

Originally posted by blike
I just built my first aerotech rocket, and I'm fascinated by the cooling mesh concept. Does anyone know how effective they are? I'm asking because I'm designing a video rocket, and I'm wondering how isolated the camera system needs to be. If the vapors are not hot, I'm thinking about just sealing the camera compartment with a bit of masking tape or something.

I built a number of Aerotech kits back in the early 90s, and the cooling mesh, I believe, is a waste of time, and marketing hype. (I'm Marketing Manager for a small UAV company, so I know hype!)

Use a Nomex or Kevlar chute protector instead, or just wadding. The mesh clogs easily with the red caps from Aerotech reload hardware, and I had to resort to a dowel with a needle in the end to remove caps embedded in the mesh. After numerous flights, the mesh will corrode, and starts breaking off in charred little strands. After about 15 flights, my Initiator managed to corrode all of the mesh, and finally none was left. The I just went to wadding.

I think "cooling" is a misnomer. It doesn't cool the ejection -- it just blocks the little burning chunks that nail your chutes. You can accomplish the same thing with two plywood rings -- both having a number of holes, but that do not align. That way the chunks cannot pass straight thru.

I give "Cooling Mesh" Two Thumbs Down ...

 

[Initiator001]

Gee, I've always had very good luck with the AeroTech 'cooling mesh' system.

I've even put it into non-AeroTech kits and it has never failed to work for me.

I've had AeroTech kits with over 40 flights and the mesh still works fine.

I use the mesh in any rocket 2" in diameter or larger. It's just too wasteful to put wadding in large diameter rockets, in my opinion. Also, I never have to worry about whether I remembered to put wadding in the rocket when I get ready to launch.

 

[rocketguy101]

Originally posted by Lee Reep
You can accomplish the same thing with two plywood rings -- both having a number of holes, but that do not align. That way the chunks cannot pass straight thru.

Centuri did a similar thing with two cardboard disks glued to a each end of a tubing coupler. One disk had a set of holes towards the outside diameter of the disk, the other had holes towards the center. These worked fairly well for their EnerJet "E" and "F" rockets. I still put a little bit of wadding for insurance.

 

[Stones]

I think if your are vigilant in cleaning out the mesh (after each flight) of rms caps and/or ejection particals, it holds up fairly well. I took a length of hanger and bent a small loop on the end to "grab" the mesh and stretch it back out. No burn marks on my chutes to date.

 

[rstaff3]

I am finally using the LOC mesh baffle that I've had sitting around on a 38mm, 4" rocket. LOC claims that as long as you don't have paper/plastic caps blocking the baffle, that you can get 10 flight out of it. They say to use a dowel with a heavy needle attached, to poke the baffle from the rear end 60 times, then shake out the residue. I'll probably clean it before each flight.

Lee is right about the way these work. The merely block the particles from the ejection while allowing the air pressure to transfer to the chute area.

 

[rocketsonly]

Would this work on a 1.56in body tube, 17 inches in length, with either a B or C engine?
-Matthew