Introduction: Laser Cut Chest
I want to first give Credit to the originator of this original chest. I saw this on thingaverse.com and it seemed like the perfect project and was really fun to build and expand upon. Also, I want to credit the user of a chest that was already remixed from the original design where he replaced the lock mechanism with a simple hasp.
Visit SeanCF's Original project here: http://www.thingiverse.com/thing:17322
Visit rmm5t's Remixed project here: http://www.thingiverse.com/thing:1128819
I liked the look, feel, size, and dimensions of the original project, but I was disappointed with the lock mechanism which drew me to the project in the first place. The lock looks and works great! The size of the lock takes up too much space in the box for my liking though. The remixed project beefed up the hinges by securing a second piece to the box and steadying the assembly. The hasp is a simpler closure that was just as effective as the lock and was smaller. I had to scale down the drawing to fit in my printable area for the laser. The chest with lock was intended to be cut out on 3mm MDF and the chest with hasp was designed to be cut on 5mm plywood. I couldn't get ahold of any decent wood that matched either size so I used spray adhesive to laminate 2 fiber slipsheets that I got from work. Each sheet was approximately 1/16" which gave me a rough 1/8" but closer to 3mm.
In my design I kept the size proportions of the original chest but removed the lock, beefed up the lid hinges, and added the hasp using elements from the lid hinges from the original chest.
Step 1: Trial and Error
My first 4 revisions are pictured here. On the bottom left is my first box. I tried later to add a hasp but couldn't remove the locking mechanism from the lid to reuse the holes. the second pic shows the demolished lock that I couldn't fix. Bottom right is that same original box made from 3mm Black Acrylic. Lock works but the material is more brittle than I'd like. the hinges broke 2 minutes after I finished because my cat knocked it off the table. Top left is my first try at designing my own hasp. I liked the decorative plate on the front but couldn't get the hasp to sit flush to the box and still have the hole for a lock be accessible. Top right shows a working version of the hasp with no decorative plate. I think its missing something.
Step 2: Finished!
Attached is my final design. File is from Corel Draw X7. Layout is 24"w x 12"t and is intended to be cut from 1/8" material. My final prototypes were in 1/8" MDF but other materials could work too. I'm still working on the Laser Settings but have found that Cutting(vector) @ 40 speed, 50 power, and 500 Freq(DPI) on my 50w Epilog Zing works nicely. I replaced the decorative plate with an engraved outline of the plate. I haven't found a sweet spot for the settings that give me the color I want in the engraving but you can program your raster settings to 100 speed and 50 power to get a nice grove. On my final prototype I made 3 raster passes to get a darker color and deeper line. the layout on 24x12 is just enough space to cutout 2 complete chests.
Step 3: Required Parts
-Cut out Treasure Chest Parts
-Elmer's Wood Glue (I used Babe-Bot 4oz glue bottle $5 from Menard's filled w/ Elmer's for precision application)
-Rubber Bands (I use them to hold all of the joints together while the glue is setting)
-1/16" Brass Dowel Pins for hinges and hasp pins (Mcmaster.com Item# 97325A105, $8.83/25pk)
-70% Isopropyl Alcohol (to wipe down cut parts, Laser cuts will leave dark sticky residue on surfaces)
-Ball Peen Hammer (Optional: pein or mushroom the ends of the pins if they are too long for the hinges or hasp)
-Needle-Nose Pliers and Cutter (to set pins in hinges and hasp and cut brass pins)
Step 4: Assembly
First take the alcohol and rub down both sides of each cut out piece. This will help remove any smoke residue from the faces of the parts and clean away any stickiness that might come from your material. When I didn't clean my pieces, my hands and fingers were stained a rusty brown color.
The 5 rectangle-ish pieces should be easy enough to figure out. Just be sure that when you attach the front face, the engraved decorative plate is facing out. i usually glue the 4 sides together and place the bottom on loosely to square up the box then wrap around the 4 sides with 2 rubber bands. Now glue on the bottom and again hold in place with 2-4 more rubber bands.
To assemble the top first separate the 3 different slat pieces into groups. there a 3 pieces with 3 holes in the center, 3 pieces with 2 holes on either end, and the remaining pieces only have 1 hole on each end. Start by gluing the pieces with 3 holes in the center to the support ribs for the top. These are the 2 thin half-circle shapes, not the 2 solid half-circle shapes. These first 3 slats will be the front of the box that the hasp fit into and should be on the bottom of the same side. Next glue on the pieces that have 2 holes on each end. These hold the hinge piece that connect the top to the bottom. these should be on the opposite side from the first slats. Now attach and glue on the solid half-circle pieces to the outsides of the slats. Hold them in place with another rubber band. Finish gluing on the remaining slats then replace your first rubber band with 4 more, wrapping them over the holes in the slats and over the ends at the glue joint.
For the hinges, grab 1 long hinge piece and 2 of the short pieces. Compare the holes on the long piece to the short pieces. the holes on the short pieces should be smaller than the long piece. Insert a brass pin into the short piece then sandwich the long piece between the 2 short pieces. If there is brass sticking out past the edges you can use your ball-peen hammer to mushroom the brass so that it doesn't slip out or you can just file it flush to the wood. Now glue the "fingers" from the long piece into the holes in the lid. these are the holes on each side that haven't been filled yet, not the 9 holes on the front side. If there are problems, try shaving just a small amount from the sides of the fingers to make it more of a cone shape and start with the top hole and pull down as you insert the next 2. Now glue the short pieces into the six holes in the back of the box.
For the hasp gather the other 3 long pieces and 2 straight pieces and 1 of the little circle plugs with the hole in it. firs assemble the straight pieces by pinning the plug between with a brass pin. Next insert a pin into each of the long pieces with the smaller hole. The piece with the larger hole can be glued into the center 3 holes of the lid. go ahead and glue the other 2 long pieces on either side with the pins sticking out. Slide the 2 straight pieces in and hold them in place by pushing the pins toward the center. Hammer, file, or cut off any brass sticking out from the hinge. Last glue the locking tab into the slot at the front of the box.
Step 5: Conclusion
Please let me know if there are any other improvements that can be made to this design. ive already looked into other pin materials ways to attach them.
Please leave comments below and let me know if there are any problems with the Corel file.