Steel Mortars

WARNING AND DISCLAIMER:  If you are underage, then consult with your parents or guardians before attempting any of this.  You are on your own - I'm not responsible for your actions or harm you may bring to others because of your actions.  Making the items described below  can result in injury or death to you or people in your vicinity. Some things mentioned here may be illegal to make in your city, county, state, or country so check the laws that apply to you before you attempt anything described here. These notes are not complete on purpose. If you are reading them and new to pyrotechnics, then you are making a mistake. Stop now - this page is not for you. Get a beginning book on fireworks (see Skylighter or American Fireworks News (very quick shipping)  for a start) and read up. You can't make any of this work without more information so read up or join a club or ask someone to help you.

Steel mortars are used for multi-break shells. A multi-break shell, anything above 2" and/or three breaks, needs something very sturdy to hold it together else the mortar will blow out its plug and rise with the shell - or worse yet, rupture and destroy the effect.  The tubes for these mortars were purchased at a scrap yard (double walled well pipe), roughly cut off, and then cleaned up and capped with some additional 5/16" steel from a piece of an I beam. Total cost was about $16 for several tubes (three 3", and one each 4 and 5 inch) and the I beam chunk.

In use, these mortars should be buried in the dirt or sand to hold them firmly. In addition, sufficient distances should be maintained from the firing line in case there is a blow-out.

The first three pictures below are edited versions from Noel Emge's fine picture prowess and used with his permission (I think) - they are from the 2006 PGI.

Steel mortar guns buried and awaiting the show

 

What happens when a shell explodes in the barrel. This was a 12" by 48" shell. I was in the stands when it popped and I could feel the blast even from there!

 

Left-overs from the explosion (see top right panel). You really want to be a safe distance from these things!

 

A length of 4" pipe found at a scrap yard. Most of this was unusable because of corrosion. However, the last four feet (not shown) was pristine and already had a cap on the end.

 

The web of an I beam makes great end cap material. And the scrap yard will sell small chunks like this fairly cheap.

 

Some capped tubes ( a 3", 4", and 5") painted and ready for use. You can see some 3" ones that were just cut and awaiting the welder. Note 4" tube on the right. It was already capped when found at the scrap yard - all that was needed was to cut it to size. Sweet!

Above is the 5" gun made from scrap double walled well pipe  - buried in the ground and waiting for some more 5" multi-breaks. Click on the above image and watch a 5" shell come out of it. The shell is Joel H.'s and was fired during the demo period of a large 4th of July  fireworks shoot.



Above is a 54" long mortar - 4" diameter. The back
was plugged with a reversed well cap and a bead of
weld was run around the inside. The result is a smooth
tube that is easy to remove from the ground.  The chain
is taken off after the gun is placed. And put on to
remove the gun from the ground.