Welding a box containing sand

[MysterG]

I want to make a box out of sheet steel, but to give it weight fill it with sand.
If I construct a box, drill a hole, pour in sand to the brim, then plug weld the hole up (don't want any filling point visible) am I likely to have any issues?
Not concerned about quality of the weld issues, more anything dangerous that might happen.

Can't imagine there would be, but posting a stupid question is better than posting on the "what stupid thing did you do today" thread

 

[pedrobedro]

I would probably just have filled it with sand before putting the last side on, can't see there being any problem doing it your way.

 

[awemawson]

Just make sure the sand is absolutely dry to not only stop your box rusting, but not produce steam when welding.

 

[Parm]

Use kiln dried play pit sand

 

[Agroshield]

Put a plate inside the container adjacent the hole with a piece of string through it. Pull into place using the string. Tack weld and cut string. It will act as a good backer for your plug weld.

 

[Barking Mat]

Put a plate inside the container adjacent the hole with a piece of string through it. Pull into place using the string. Tack weld and cut string. It will act as a good backer for your plug weld.

Fine Idea. Or leave a welding rod attached to it, to pull it up.