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MortarRack
12-21-2020, 06:28 PM
I am planning on building some mortar racks soon, I just had a few questions.

1. What is the safest way? 6 inline? 12 (double row of 6)? 9 Square? Milk crate? (I will be using 5" 60G shells)
2. What is the best? I have seen a lot of 6 inline racks for sale.
3. How far should the audience be from the launch site?

I will be using treated 2x12s for the base, 2x4s for the sides, and stripped 2x4s for the ends.

I would like to know what happens when say a 5" can shell CATOs in the middle of a rack.

Rick_In_Tampa
12-21-2020, 07:35 PM
Download or find a copy of NFPA1123 and it will tell you all you need to know about operating a fireworks display safely.

https://www.nfpa.org/codes-and-standards/all-codes-and-standards/list-of-codes-and-standards/detail?code=1123

The short version is, the audience needs to be 70' away for every inch in diameter of shell. The largest 1.4G aerial shell is 1.75" so your audience should be at least 122.5' away.

As for the design of your racks, I'll leave that to others to provide their opinions. Just remember, the term "the best" is a purely subjective determination. If "the best" suggestion doesn't work for you, then it's not really "the best" now is it? Only you can determine what is best for you.

Now if you want to talk about how to design a rack to ensure it is as safe as it can be, (and I honestly think that is what you're really going for) then you will have a lot of help with that I am sure.

topshelfpyro
12-21-2020, 08:13 PM
I am planning on building some mortar racks soon, I just had a few questions.

1. What is the safest way? 6 inline? 12 (double row of 6)? 9 Square? Milk crate? (I will be using 5" 60G shells)
2. What is the best? I have seen a lot of 6 inline racks for sale.
3. How far should the audience be from the launch site?

I will be using treated 2x12s for the base, 2x4s for the sides, and stripped 2x4s for the ends.

I would like to know what happens when say a 5" can shell CATOs in the middle of a rack.

This is kinda like asking what is the best oil to use in your car.....
1. you can build them however you want. I prefer 6 shot racks that I usually screw together 4 at a time to make 24 shot "racks" all consumer shells come in multiples of 6 IE:6, 12, 18, 24 (I currently have 120- 6 shot racks)

2.The best is whatever you decide for you. some like 10 shots some 12 some 50....can't say why but that's what they like

3. as stated previously at least 100' is best

Use 2x3 available at homedepot etc for the base and ends....I use 5/8" plywood for the top side and 5/8" OSB for the bottom sides there are reasons for this but its a hot topic.....

Don't use milk crates.....

Something you may not know with consumer fireworks ALL shells are limited to 60g of comp including the lift charge....it doesn't matter if the tube is 10" long its the same comp

When a shell pops in the tube what happens depends on alot of factors, it could simply look like a mine if your lucky or it could destroy the rack and scatter tubes

MortarRack
12-21-2020, 08:17 PM
Is there a way to prevent the destroying of racks when a shell CATOs? Are you saying that 2x4 won't work for the sides?

topshelfpyro
12-21-2020, 08:37 PM
Is there a way to prevent the destroying of racks when a shell CATOs? Are you saying that 2x4 won't work for the sides?

Of course but the added cost and weight are generally not worth it. distance is your friend.

No, but I believe there are better options for sides than 2x lumber. If you do have a cato 2x lumber will simply "let go" generally so the whole stick comes off. with OSB it will chunk out and the plywood on top is much stronger than 2x lumber. generally the bottom side is just below the tube plug height

displayfireworks1
12-21-2020, 09:31 PM
I'm assuming you are using all Consumer Fireworks. Build your racks and setup your show as if something it going to tip over and/or blow part. I apologize for not reading all of you post, I see you are new to the forums. Where are you at in the mix? Do you hand light your items one and a time, are you using any extra fusing to set off multiple items at time, or do you have a fireworks firing system? Or, are you planning for your future fireworks endeavors as your budget allows?

MortarRack
12-22-2020, 09:01 AM
I'm assuming you are using all Consumer Fireworks. Build your racks and setup your show as if something it going to tip over and/or blow part. I apologize for not reading all of you post, I see you are new to the forums. Where are you at in the mix? Do you hand light your items one and a time, are you using any extra fusing to set off multiple items at time, or do you have a fireworks firing system? Or, are you planning for your future fireworks endeavors as your budget allows?

I am using all Consumer Fireworks, and I will be fusing them up so I only hand light a few fuse

MortarRack
12-22-2020, 09:02 AM
Of course but the added cost and weight are generally not worth it. distance is your friend.

No, but I believe there are better options for sides than 2x lumber. If you do have a cato 2x lumber will simply "let go" generally so the whole stick comes off. with OSB it will chunk out and the plywood on top is much stronger than 2x lumber. generally the bottom side is just below the tube plug height

Thats a bummer, because I already bought the 2x treated wood. With huge angle brackets. It seams VERY strong.

Greenville Pyro
12-22-2020, 10:03 AM
See my post for rack building. I build a lot of racks. 6's or 10's. Depends on your preference. Always use HDPE or fiberglass for blowout protection. Best scenario is you flowerpot. Worst scenario is that something blows apart with live firing shells. Your rack may or may not survive. Who cares if everyone is safe. NO MILK CRATES. They are all over the internet but very scary if something blows up. As far as spacing from the audience, look at some videos of 1.75 consumer cans. Many travel 200 or 225 feet up. At least 150. Plus a 50 foot blast radius. No one in my shows gets closer than 300 feet for safety except me. PM me if you have more questions or for advanced rack building in the future (angles etc)

http://www.pyrotalk.com/bulletin/showthread.php?8351-Mortar-racks

WithReport
12-22-2020, 11:36 AM
I am planning on building some mortar racks soon, I just had a few questions.

1. What is the safest way? 6 inline? 12 (double row of 6)? 9 Square? Milk crate? (I will be using 5" 60G shells)
2. What is the best? I have seen a lot of 6 inline racks for sale.
3. How far should the audience be from the launch site?

I will be using treated 2x12s for the base, 2x4s for the sides, and stripped 2x4s for the ends.

I would like to know what happens when say a 5" can shell CATOs in the middle of a rack.


Distance will always be the best approach. As for how to build a safe rack, I don't know that there is an absolute safe rack (NFPA gives you guidelines, but does not provide specific construction or design approaches) - but requires distance. The goal is to minimize what effects a CATO may have. If a shell CATOs and there is no other tubes near by there is no potential for it affecting other tubes.

So the safest rack is probably a single tube. I saw this image earlier this year and saved it. It is an example of a very successful rack. It sustained an impressive CATO (especially for a consumer shell) and did no damage to the neighboring tubes and all tubes (even the cato'd tube) remained pointing up.


5448


I don't know that any of our multiple tube racks can perform as well as this.


I do have many similar racks of just these Excalibur tubes screwed into 2x6s studs. The are gangly to move around and take up space, but I will use them for certain shells that I find are a bit more powerful than expected.

Here is how I store these types of racks - these ones are mine:


5447


I have started taking some of those long Excalibur tubes racks on 2x6 down and making tubs out of them. The concept is fairly similar, but provides some angle and greater density. These are my typical go-to racks that I grab on a last minute shoot.


54455446



I do still build racks for DR11 tubes. I never double row tubes in the same rack - the goal is reasonable space between tubes. I've stayed with 5 or 6 tubes in a row and settled on 6 going forward. I see some of these 10 and 12 tube racks and in my opinion that is too gangly and have the potential of allowing more tubes to come loose. Other's may have a more comfortable approach with more tubes or double rows.

5444


The benefit of a lot of single row racks is that you can then just arrange them with end boards for whatever the required angle is.


5443


I also use spacers on all new racks. Here are my thoughts

1) We've all seen pictures of bulged tubes after a cato - end spacers provide room for that tube to expand without putting load on the 2x3 end frame.
2) The gas and pressure has to go somewhere. Force = Pressure X Area. The less tightly you contain the tube, the less area you have for the pressure to work against and more room for the pressure to escape
3) Long screws or nails through the end frame when setting up racks don't go into the tube. Probably not a big issue with my DR11 racks for stuff that I setup, but I've seen people nail right into (and in some cases through) the wall on larger tubes.
4) Gaps provide areas for running igniter wires or tucking them out of the way.
5) The extra spacing gives you some additional options for timing fuse on chains of shell you fuse up. Having all the tubes butted up against each other limits some timing options, if that is something you are after.




https://www.youtube.com/watch?v=M1aYZbdoAMY


I'm open for other suggestions, too. I have a few additional thoughts on a very safe consumer rack, but not sure the effort is worth the payoff - especially if always following distance on shows.


Again, these are just my opinions and approaches. You are likely to come across other good suggestions, too.