How To Make a Treasure Chest


My kid has been on a treasure kick and I've been wanting to play with my new welder, so I made him a treasure chest for Christmas!

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My youngest son has been on a pretend treasure kick lately and I’ve been looking for a simple welding project to play with my new welder, so it seemed like a great idea to make a simple treasure chest as a last minute present for him.

I did this over two days, but it could easily be an afternoon project - or at lot less if you’re not a complete novice welder like I am.

This is my second time TIG welding, and first time doing a welding project solo. The 1” angle iron is from my local big box, which isn’t an economical option if you need a lot of steel, but isn’t bad for a small project like this.

I’m not a big angle grinder fan, so I also picked up one of Diablo’s new steel demon blades so I could cut the steel with my circular saw and I was super impressed with how well it cut. That said, as a rule cutting steel with wood blades is a great way to end up with pieces of broken carbide teeth embedded in your body, so get a blade meant to cut steel or stick to cut off wheels.

Once everything was cut, I used my grinder to put some bevels on the joint to have space to fill up with weld. Granted.. my cuts weren’t at the perfect angle so there was plenty of gap in the joint without the bevel.

I used some magnets to hold everything together and made sure they all of the corners were square despite my angles and lengths not being consistent.

Then I set to welding up the bottom frame. I put some tacks on all the corners to hold them together before welding the whole corner. One thing I can pass along is the importance of tack welds. Welding introduces a lot of heat to the metal.. I mean, it creates a puddle of molten metal. When that puddle cools, it contracts which introduces a lot of pressure into the piece.

The pressure from tack welds generally isn’t enough to pull your pieces out of alignment. But if I had welded an entire corner without already tacking the other corners in place, then the tension from that corner cooling would’ve pulled everything out of alignment with so much pressure I wouldn’t be able to pull them back into alignment.

With the base rectangle welded, I moved on to the uprights. The metal is just going to serve as a frame, then I’ll add some wood panels to make up all the sides and lid. Again, I used the magnets to hold the metal in place as I applied some tack welds, and then followed up by welding the entire seam.

After I had the uprights welded, I switched to cutting some flat bar that’ll go around the top of the box, this will give something for the lid to meet up to and a place to weld the hinges on. When I got to this point I remembered that TIG is a really finicky process, the most sensitive of welding processes. So besides my poor technique, one of the things working against me was that I hadn’t ground off the mill scale near where I was welding. Mill scale is the skin that develops on steel as a byproduct of how it’s manufactured and often contains contaminants that can weaken a weld.

For this project, strength isn’t as much of a concern as say with welding water lines for a nuclear power plant, I mean bubble gum would probably be strong enough for this. But I thought if I prepped the metal better than my welds may look nicer, I was wrong, but it’s good to get in the habit of doing proper material prep anyway.

Off camera, I set up the angle iron for the lid on top of the box structure and used the magnets to hold everything in place and tack welded them. I figured it was less important to make sure that the lid is perfectly square so much as making sure it matched the top of the box.

One of things I learned during this project was that I was trying to move too fast, often I’d start trying to add filler metal to the weld before I had a puddle formed - that is, before I’d introduced enough heat with electricity from the torch to melt into a molten puddle. So I took a breath and started slower, waiting to see a puddle form before adding metal and moving the torch along the seam, that helped a lot.

The other thing that was helpful was remembering I was working on a pretend treasure chest, a small box, not massive I-beams on a sky scraper, so if I was in a bad position I could just move the piece and make a prop to rest my hand on.. no need for contortions or floating my hands out in space.

Once I finished the lid frame, I used some magnets to hold the back of flush to the box and used a grinder to remove the mill scale where the hinges would get welded on. Then I welded those on.

With the box structure done, it was time to prep the wood. For the panels I’m just using a cedar fence picket. I like the look of cedar, it’s light so it won’t add much weight, and fence pickets are dirt cheap. They’re also really rough though, so I ran both sides through the planer to smooth it out before cutting it down off camera into the pieces I needed.

For the panels that go inside the box I cut them to be super snug and friction fit in place, then put some CA glue in the seams for a little bit of insurance, but that was probably unnecessary.

To attach the top to the lid I just used some polyurethane construction adhesive. Now if you think I didn’t take wood movement into account, you’re right. But pieces this size will barely change with the seasons and for a variety of other reasons, I’m not worried about it - but you can be if you want to.

After grinding down all of my ugly welds, I took it out side and sprayed on 3 coats of clear enamel to seal the wood and metal.

She’s not much to look at, but my kid was really happy with it on Christmas morning and playing with it since, and it was good welding practice for me. Best of all, something like this is supposed to look kind of rustic and imperfect anyway, so my poor welding just adds to the character instead of detracting from the project.