Over the past few years, I’ve established a fun and entertaining tradition with my nephew for holiday gift giving. As with many teenagers, he had few needs/wants and I resorted to cash or gift cards. However, these are BORING to open so I started to get creative about how they were wrapped.
It started a few years ago by putting a box inside of a box inside of a box. It was good fun to watch him frustratedly open smaller and smaller boxes. It became a family joke to time him to see how long it took. It was well received and created a lasting memory. The next year, we went up a notch and added even more boxes/layers. It took him longer to open and we all had a good laugh. The next year – another notch: This time we wrapped it in dozens of layers of cling-wrap and added many small bills throughout the layers to make it more of a hunt and discourage him from cutting the outer layers to get to the center.
That brings us to this year. As he now has a serious girlfriend, we suspect we may not be seeing much of him in coming years since her family lives far away. I’ve been devising a plan to make the most challenging gift yet. Did I go too far? You decide after reading.
Build
In keeping with my recent theme of consuming my surplus scrap collection, I selected some available material and paid nothing out of pocket for this whole project. I started with some 3/8″ plywood which I cut into two 9″ squares. Next, I did the same with a piece of left over 1/8″ HDPE sheet.
I sandwiched the HDPE between the two pieces of plywood and used my miter saw to trim the corners to make an octagonal shape. I marked the edges so I could re-assemble easily as these were not perfectly symmetrical cuts. Why octagonal? I wanted to increase the difficulty of opening by having more than 4 bolts, and cutting the corners off the squares seemed like an easy way to quickly double the number of corners.
On one piece of plywood, I marked out spots for 8 holes about 1/2″ from the edge. I clamped all 3 pieces together and took it to the drill press where I quickly drilled 8 holes through all 3 pieces of material at the same time to ensure alignment.
Next, I drilled 4 holes on the interior of the HDPE sheet and used a jig saw to cut out an interior rectangle about the size of a gift card. I had some left-over 1/4″-20 x 3″ carriage bolts, washers and nuts from a previous project so intended to use these to secure the sandwich together.
A this point, my devious plans continued to evolve and it occurred to me how challenging this might be to open. It might be necessary for him to use some drastic means to open this which could destroy the contents. Crowbar? Yes, likely. A saw? maybe, if he has one available. Fire? Unlikely, but possible. Lots of possibilities that needed to be considered. So, rather than risk damaging the actual gift, I wrote out a simple note that instructed him to collect his gift from his Aunt.
After folding the note and closing up the sandwich, I threaded the washers and nuts onto the bolt and tightened them with a wrench. I then took an angle grinder and cut the excess bolts off, leaving a flush surface.
Eager to use my new welding workstation, I then took the enclosed sandwich over to my welding table and proceeded to weld the nuts to the bolts. I did this for 7 of the 8 bolts. C’mon, I’m not a MONSTER – I had to make him feel like he might have a fighting chance by leaving one bolt unwelded!
This weld was not easy because I struggled to find a way to attach the negative clamp. Since the sandwich is not conductive, I had to squeeze the ground clamp onto the head of the carriage bolt underneath to get a proper weld. I had to move the negative clamp with each weld. With the bolt counter-sunk into the wood, there was not a lot of area to apply the clamp, and it slipped off several times through the process.
I used a 40 grit flap disk attachment on my angle grinder to grind down the welds and smooth most of the rough edges. This worked very well and I got a nice smooth, uniform finish that effectively hid my poor welds. At first glance, It’s not obvious that there are welds, which was my intention.
Finishing
Because of the octagonal shape, I was inspired to hit the bolted sandwich with a coat of red paint. I had some red spray paint on hand from some previous project I can’t recall. The welding left some deep scars on the plywood, so it required 2 thick coats to hide the blemishes – they are still noticable, but I’m not going to fuss on making it beautiful since it will likely be destroyed during the opening process. The paint also allowed me to hide the fact that the bolts were welded a bit.
As a final touch, I ran a quick job on the Cricut and printed some letters in white vinyl with the words “GOOD LUCK”. I didn’t think anything more really needed to be said. :) I applied clear nail polish on all the edges of the vinyl to prevent them from curling since the plywood was not perfectly smooth.
Conclusions
This will be an interesting puzzle for my nephew to solve because:
- Carriage bolts have no screwdriver slot or head for a wrench to grip. They are intended to be flush and look nice. Without the ability to grip the bolt head, it will just spin endlessly and not easily allow the bolts to be removed.
- Even if there was a way to grip the other side, the welding has fused the nut and bolt together and it will require a TREMENDOUS force to break the weld and unthread the nut.
- With bolts at each of the 8 corners, there is little room to insert a wedge to separate the layers.
- The sheer strength of a 1/4-20 bolt is 4700 lbs, eliminating the bolts as a weak point in the puzzle.
- Because of the construction approach of using layered laminates with perpendicular fiber directions, plywood is VERY strong and resilient. Coupled with the core which is HDPE, this sandwich will be very durable.
- We’ll be celebrating at my nephew’s house when he receives the gift, so he’ll have access to all of his tools. I’m not sure, exactly, what tools he owns, but I do know he won’t have to use only his hands to make attempts to open the gift.
I asked myself many times throughout this build: How would I open this gift? Here’s what I came up with:
- Easiest: If I could somehow remove one of the bolts (i.e. the one that isn’t welded), then I could use a flat-head screwdriver or some kind of pry bar to wedge the sandwich open by cracking the plywood and retrieve the contents.
- Medium: If I got frustrated enough, I might just take a hammer to this “box” and smash the wood till it splintered/cracked and then retrieve the gift. Due to the small size and the layered, multi-material approach, this would take quite a bit of effort, but it is possible.
- Advanced: I could just take it to my bandsaw and start cutting the material around the bolts to remove them. I could stay close to the edge and not risk damaging anything kept in the middle. This might also be done with a jig saw or possibly some other kind of saw, but a bandsaw would give the most control needed to do it safely.
Of course, my nephew won’t know that there is no gift inside, so it might cause him to be reluctant to take any kind of destructive action that could potentially damage the contents. I’ll have to think hard about if/when I give hints or how much I do or don’t tell him about the contents.
There is also the possibility that he’ll just give up and I might have to reluctantly hand over the actual gift when he decides to not play my game. However, knowing how competitive he is (multi-sport, decorated athlete), I doubt that will happen. Any way it happens, I’m looking forward to pulling out my stopwatch when he’s handed the gift to see how long it takes him (which will likely further motivate him).
I’ll most definitely be prepared to step in if he attempts to do something unsafe – I certainly don’t want anyone getting hurt. Finally, this is meant to be fun and in good sprits, so if emotions boil over, I’ll call it off quickly. I hope this will be yet another fun and lasting memory for a simple gift.
How will I top this next year? I’m not even sure there will be a next year with him, but if he does attend our family gathering, I’ve got an idea that may involve a welded metal box…
Update: 16:22
Yup, 16 minutes and 22 seconds was all it took to open the gift! Clearly, I underestimated his resolve and ingenuity. He started by immediately grabbing a wrench and attempting to remove the bolts, but quickly determined that the bolts were welded and would not unloosen. There was a fleeting thought of just giving up, but then he surprised me and grabbed a multi-tool with a metal-cutting bit. His plan was to plunge down and cut each bolt through the wood/plastic. However, he then changed tactics and switched to a wood-cutting bit and plunge-cut wedge-shaped cuts to remove the bolts. I encouraged the use of a vice which made the process safer. I also encouraged the use of eye protection. When none could be found, he grabbed a pair of dark sunglasses – better than nothing!
I must admit that I was not prepared for him to grab the PERFECT tool for defeating this puzzle so quickly. It happened to be out and available because of a previous project, so there was little think time required to select the tool.
Everyone got a good laugh and he got his gift. No one was injured and no one got frustrated. Overall a success, but certainly I’ve got some planning to do to turn up the difficulty for next time.
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