8-Shot Fiberglass Fireworks Mortar Racks

Learn the Easy Way to Make Versatile
8-Shot Fiberglass Fireworks Mortar Racks
Just Like These...

Learn the Easy Way to Make Versatile 8-Shot Fiberglass Fireworks Mortar Racks

If you plan to shoot a backyard display this year there is a good chance you'll be buying some shell kits to punctuate your show.

Every year consumer shell kits get better and better, but the single shot tubes they come with are about as useless as can be. The tiny bases tip over easily and since they only give you 1-2 tubes your constantly reloading them, in the dark, it's a mess. Not to mention that your audience is bored to tears watching you shoot one shell at a time.

It's time to step up your game and build some of these versatile 8-Shot mortar racks!

Before we get started it's worth mentioning that by making some simple adjustments to the dimensions you can make this racks as big or small as you like. Some people like big 15-Shot racks for their finale, while others prefer to make smaller 5-Shot racks so they can spread out the show over a larger area. Personally, I find 8-Shot to be a good balance between light-weight and easy setup.

Next, you'll have to decide if you'd like to use HDPE or Fiberglass mortars. Skylighter sells both and either is a great choice. Again, my personal preference is fiberglass as they are lightweight, last for hundreds of shots and usually cost a little less than HDPE. No matter which you choose these racks should last you for years and years as long as you keep them clean, dry and out of the sun.

WARNING: You may be tempted to use PVC or other plastic pipes from the local hardware store but this would be a potentially fatal mistake! PVC and its related plumbing pipes CPVC, ETC shatter and create deadly shrapnel. Many have been injured ignoring this advice. While no material is 100% safe HDPE and Fiberglass have become the gold standard because of there proven track record.


What you'll need:
  • Some mortar tubes (preferably divisible by the number of tubes per rack)

  • Quality wood screws. You will need 4, 3.5" screws and 22, 1.25" screws per rack for these instructions.

  • Plywood (3/8ths to 5/8ths works well for this application)

  • Optional: OSB (Oriented strand board) for the lower rails.

  • 2x3 Studs or similar material.

  • Screw gun

  • 1/8ths drill bit (optionally with countersink)

  • Optional: Construction glue (such as liquid nail)

  • Optional Saw (Wood can also be cut for you at the lumber yard)
Note: Screws were chosen for this project simply because it keeps the project accessible to most everyone. You could assemble the project with a hammer and nails, sheet good stapler or other means. Whatever you use, be sure it is strong enough to take the repeated beating a mortar rack receives.

Let's Make This Rack!
8-Shot Straight Fiberglass Fireworks Mortar Rack
8-Shot Straight Fiberglass Mortar Rack


Introducing the parts

Each rack will consist of a frame made of 2 vertical supports and 1 base. For this project, I will be using 2x3 SPF lumber from the local big box store. You will also need 2 lower rails and 2 upper rails. Each of these parts is shown in the picture below.

Parts of a mortar rack
Parts of the rack

Our upper rails will be made from 7-ply 5/8ths plywood for strength. Our lower rails can also be made of plywood or they can be made from OSB a type of manufactured wood board that is made of wood strands glued and pressed into a sheet.

The benefit of using OSB for the bottom rail is that it fractures easily allowing gasses from an exploding shell an escape path. By using OSB when a consumer shell fails inside of a mortar, many times the remaining mortars continue facing upright. I have participated in tests where a shell is intentionally loaded upside down to cause a failure and OSB lower rails have proven to provide some additional safety. The downside of OSB is durability and strength.


Measure twice - Cut once

Measure the mortars you plan to use. Take note of the outside diameter at the widest point as well as the length. The measurements will be used for adjusting the rough dimensions I will provide below.

Note: if you do not have access to a table saw, or chop saw most big box stores such as Home Depot or Lowes can cut the wood for you for a small fee.

As mentioned above I've chosen fiberglass mortars for this project and I will be giving rough dimensions for fiberglass mortars. Because fiberglass is so strong, the mortars tend to be smaller in size (thinner walls) then DR11 HDPE. No matter which you choose make sure to check your dimensions as you go.

Your vertical supports will be cut to the same length as your mortars. And will need to be the same width or slightly wider than your mortar tubes. Your base will be the same thickness as the vertical supports but will need to be long enough to support the number of mortars you are planning on including in your racks, plus support the vertical supports. For me, this works out to the dimensions you see below.

Vertical Supports: 12" x 2.25"
Base: 20" x 2.25"
Rails: 20" x 5"

Dimensions for making a 8-Shot Fiberglass Mortar rack
Dimensions shown on rack parts

Note: You may notice that my 2x3s are thinner than a normal dimensional lumber. I do this because I want my mortars to be held tightly enough that they will not spill out or bounce out from the force of a lift charge.

Again, here you have an option, If you have access to a band saw, table saw or plainer you can easily make your racks tightly fit your tubes. A tight fit means you will not need to glue your tubes in place and that they can be removed in the event one is damaged. If you do not have access to a tool that can reduce the thickness of your 2x3s, you can glue your mortars in place with a little liquid nail.


Assembly of Your Mortar Racks

Once your parts have been cut out. The first assembly step is to attach the vertical supports to the base. I will be doing this using 3.5" long, coarse thread construction screws (Note: do not use drywall screws, they are too brittle).

To prevent the wood from cracking I will pre-drill 2 holes on each side using the 1/8" drill bit. Mark your base 3/4s of an inch from the edge and drill two holes. To keep things tidy I will be countersinking my drilled holes.

Pre Drilling

Now that all of my bases have been drilled I can attach the vertical supports. This step is most easily done on a flat tabletop with the parts laying on their side or by leaning the vertical supports against something the same height. In my case an old shop bucket.

Frame assembled

Note: don't worry if your frames are not perfectly square at this point. When you add the rail they will force the frame to square up.

With your frames assembled, it's time to attach rails to one side of the frame. Whether you are using OSB or plywood for your bottom rail the screw pattern will be the same.

How to Assemble your Mortar Rack

I'll be using 7 screws for the bottom rail and 4 for the top rail. The location of each is shown above.

Building a 8-Shot Mortar Rack

Now that we have the rails in place, If you did not reduce the width of your vertical supports now is a good time to apply ample glue to the top of the base.

Glue Pattern For A Mortar Rack
Displaying glue pattern on the base

Fill your finished frame with tubes and screw in place the rails on the opposite side.

How to Build a 8-Shot Fiberglass Fireworks Mortar Rack

With a little practice you'll be able to knock them out so fast you will not be able to keep up with yourself.

Make this fireworks mortar rack quick and easy - Project Plans


Finishing your racks.

These straight 8-Shot mortar racks really are versatile. They are compact and sturdy. Perfect for festival balls, mines, even holding roman candles and barrages of stinger missiles.

But before we shoot anything you'll need to add outriggers to add stability to your rack. If you have leftover plywood, scraps of 2x3 or 2x4s, cut a couple 20-inch lengths and attach them to the bottom or bottom sides of your rack as shown below. I find that on the bottom sides provides the best strength and stability.

Simple Morgar rack for fireworks - Easy to follow instructions
Painted rack with side or bottom supports

As you can see of the picture above you can add your own artistic style to your finished racks. A quick coat of spray paint or wood stain can truly make them your own creation. Coating the wood with urethane, paint, or clear coat has the added benefit of protecting the wood. Remember rain strikes unexpectedly--often at the worst possible time.


Angling your new fiberglass mortar racks

But what if you want to fill the sky by shooting a fan of shells or mines? Well, we got you covered. When attaching the outriggers you can connect several racks together, either straight up or angled (left and right).

Build a 24 shot fan rack for your fireworks displays
3 racks connected with side supports
angled left, right and straight up.

You can use this method to support as may racks as needed in any combination of straight up and angled.

Build this mortar rack for your fireworks displays

Just be sure to make sure your racks are strongly connected and do not wobble around. For the safety of your audience, you must take responsibility to ensure that all fireworks shoot safely away from your guests. Consider adding sandbags to ensure a safe time is hard by all.

You now know how to build a very versatile 8-shot rack that can be used to shoot shells and mines. You know how to Fan your new racks to fill the sky with fireworks. And you know how to brace the racks for safety and stability.

So really there is only one thing left to do... It's time to go buy a whole bunch of mortar tubes and build some amazing racks that will last you years and years. Don't forget, send us your pictures of your finished creations and amazing paint jobs. We love seeing your creations!
Previous article Shell and Rocket Training Kit Instructions
Next article How To Make Black Powder Rockets