Mid to High Power Blast Deflectors

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cwbullet

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I have built two mid to high-power launch pads and want to add a blast deflector to the bottom of the rail. I am looking for ideas on how to do that.
 

dhbarr

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One of the reasons I favor disker blades is that many already have a square center hole just a bit bigger than 1in * 1in
 

Tobor

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When I discovered the Jawstand launchpad thread, Corzero turned me on to the Wilton Cake Lifter as his choice for a blast deflector. Unfortunately, it is not listed on Amazon any longer but there several knockoffs available like (This one).
 

Scott231

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I believe you can go to Menard's, Home Depot etc. and find a piece of flat steel for less than $12.00
 

teepot

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I use a AR 500 rifle gong for a blast deflector. It is indestructible.
 

Rocketjunkie

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Chuck, I believe I have a couple more of the stainless plates I used on the X pads. I'll check the storage unit next visit.
 

bobbyg23

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I believe you can go to Menard's, Home Depot etc. and find a piece of flat steel for less than $12.00
Do you know what department this is in? I have looked and can't find any that cheap.
 

JimByrne

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I have built two mid to high-power launch pads and want to add a blast deflector to the bottom of the rail. I am looking for ideas on how to do that.
Show a picture & we can give you some ideas---I have built several
 

Scott231

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1616032898021.png

Keep scrolling around, you'll find something that works in here.
 

H. Craig Miller

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Here's a low and mid power blast deflector made from an Aerotech Mantis launch pad...
Blast Deflector.Composite.jpg
In those instances where additional blast deflection is desired, the post slides through the center hole of a 14" diameter Diablo high speed metal cut-off disc before being inserted into the stand.
 

GrouchoDuke

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I have one of these that I use for my towers (so far, up to J1026). It's a little thinner/more flexible than I'd hoped, but it works well. https://www.amazon.com/gp/product/B01JAPJYHK/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

Cake lifter launch deflector in action (J1026 & I224)...
Screen Shot 2021-02-07 at 8.37.28 PM.png

Screen Shot 2021-03-19 at 12.09.24 AM.png


EDIT: FWIW, I did this G150 launch without that pie spatula...it's a G motor, what harm could it do? Yeah, it blasted about a 1 foot diameter, 1/2" deep hole in the lakebed. Don't do that.
YouTube title image - lens corrected.jpg
 
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Mike Haberer

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When I discovered the Jawstand launchpad thread, Corzero turned me on to the Wilton Cake Lifter as his choice for a blast deflector. Unfortunately, it is not listed on Amazon any longer but there several knockoffs available like (This one).
I use this as well. I haven't launched anything larger than an I on it yet. It didn't get damaged by it, so I expect it can handle at least a K.
 

ep29030

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If you find a welding shop, most of them can cut a piece of metal (mild steel or stainless steel) to about any size and metal thickness you want. I would get a 16-18 ga. steel thickness for most blast deflectors. I put an 18 ga mild steel plate on the ROCI large pad, and it's held up to J-K motors with no issues. It is tack welded to a piece of 3/16" x 2" wide piece of flat steel that runs down the middle on the underside, and is bent at a 45 degree turn where it bolts to the rail. Recommend the reinforcement steel under the plate--some motors hammer that blast deflector pretty hard. We used some ceramic tile blast deflectors that were cracked by H-I motors.
 

ep29030

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One nice thing about deflectors at steeper angles, like 20-45 degrees, is that they deflect exhaust away from the underside of the rocket. Flat (horizontal) deflectors send the gasses back up to the rocket, burning the aft end.
 

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One nice thing about deflectors at steeper angles, like 20-45 degrees, is that they deflect exhaust away from the underside of the rocket. Flat (horizontal) deflectors send the gasses back up to the rocket, burning the aft end.
Only if they are too close to the rocket. Our x pads are all horizontal and I have yet to see a burned rocket.
 

FredA

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Angled blast deflectors may also change your flight path.

Remember - at liftoff, the force on the blastplate equals the force lifting the rocket.
Angle the blastplate and that becomes a force trying to bend your guidance rod/rail.

If you must use, mount at the very bottom where the rotational torque is lessened.
 

ep29030

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Only if they are too close to the rocket. Our x pads are all horizontal and I have yet to see a burned rocket.
Good for you guys. It's rare that I don't have a blackened/burned rocket just about every time I fly, with about 4-6 inches of clearance to blast plate. Seems you would need to be 10-12 inches above the deflector to avoid it.
 

cwbullet

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Good for you guys. It's rare that I don't have a blackened/burned rocket just about every time I fly, with about 4-6 inches of clearance to blast plate. Seems you would need to be 10-12 inches above the deflector to avoid it.
5-6 is enough for me. Are you flying sparkles?
 

mrwalsh85

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What, everyone's scared of a little battle scar?

I still have scorch marks from the flame deflecting up the rail opening to my rail buttons on a couple of my birds. That's actually pretty awesome. No damage otherwise. L's and M's.
 

cwbullet

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What, everyone's scared of a little battle scar?

I still have scorch marks from the flame deflecting up the rail opening to my rail buttons on a couple of my birds. That's actually pretty awesome. No damage otherwise. L's and M's.
Concur. It adds character. Much better than road rash.
 
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