Roll-up Chess/Checker - magnetic *** UPDATED***

prusaprinters

Background:First of all, this was inspired by a commercially available product. However, as reviewers indicated, the pieces do not stay in place as intended, and does not include checkers pieces.So, the challenge to design a portable chess and checkers set that would allow players to have a match anywhere, and roll it up after a match or even in the middle of the match and resume the match at a later time. This is great for students to play in between classes, or during break, or anyone who loves a nice chess match. The approximate dimensions of the chess/checker set when rolled up is ~3.5in ø (~86mm ø) x ~ 8in (~204mm). Weighs ~453g (~16oz). This is what a 24oz (700ml) water bottle looks like next to it.The chess pieces are 15mm ø x 10mm, which is about 6 US dimes in height and below is  what it looks like next it.The checker picks are 15mm ø x 6mm, which is about 4 US dimes in height and below is what it looks like next to it.Project considerations:The main body of the chess board is 233.7mm x 204mm.  Because the main body uses print-in-place design for all the moving parts, this will unfortunately not fit on a Prusa mini. This barely fits on my Prusa mk3s+ because it was printed with 8m brim.UPDATED: Smaller version now available. Main body is 211.95mm x 190.32mm.I printed this entire project using Prusament ASA on my Prusa mk3s+ inside an enclosure. The default print profile with brim still had a partial failure due to wrapping. So many changes were made to the default Prusament ASA profile help equalize the structural pulling forces between the perimeter and the infill (detailed print settings below). Your experience may vary :)Challenges:ASA/ABS is known to wrap during printing. Enclosure is highly recommend for this project if ASA/ABS filament is used. Keeping the polarity of all the magnets while attempting to glue things together with epoxy was the main challenge. ***VERY IMPORTANT*** All the pieces and the play surface magnets MUST BE aligned in attraction orientation. Working with 5 minute epoxy and strong neodymium magnets were challenging. Magnets would want to move the tiles during the glue up process. So, you'd have to work quickly and accurately (making sure the magnet orientation is correct). I had a few pieces that I had to reprint because the magnet flipped during glueing process.Required materials to complete this project:214 -  10mm x 1.7mm neodymium magnets. Amazon have quite a few sellers all have these magnets listed as 10mm x2mm. However, their actual dimensions are 10 mm x ~1.7mm. This Amazon Link is what I used.Smaller board option - 212 -  10mm x 1.7mm neodymium magnets. Amazon have quite a few sellers all have these magnets listed as 10mm x2mm. However, their actual dimensions are 10 mm x ~1.7mm. This Amazon Link is what I used.24 - 4mm x 1.7mm neodymium magnets. Amazon have many sellers all have these magnets listed as 4mm x2mm. However, their actual dimensions are 4 mm x ~1.7mm. This Amazon Link is what I used.Any 5 minute epoxy or glue of your choice for the material used in printing. I didn't go with CA (cyanoacrylate aka super) glue as it does not have any working time, additionally, if a bit too much glue is used, the risk of creating a white haze on the part was very likely. This Amazon link is what I used.Step for completing the project: (This is my approach, but your milage may very)Print the main body.Test all the print-in-place hinges are working properly by rolling up the chess board  ensuring that the chess board will close properly.Print the rest of the black tiles, chess, checker pieces and all of its spacers.Using a #1 x-acto knife, carefully remove the supports from the chess pieces, and save these supports pieces as the inlay pieces for the white chess pieces. This part is completely optional. The designs of the pieces can just be painted too.Change to white filament (might consider wiping the nozzle clean and extra purge to ensure all the black filament residue are cleared out of the filament path)Print the rest of the white tiles, chess pieces and all of its spacers.Using a sharp #1 x-acto knife, carefully remove the supports from the chess pieces, and save these supports pieces as the inlay pieces for the black chess pieces. This part is completely optional. The designs of the pieces can just be painted too.Test fit all the tiles to the main body. Test fit every inlay for every chess piece to ensure proper fit.Glue all the magnets to the underside cavity of the tiles. Again, very important that all the magnets in this step are correctly oriented.Glue all the magnets that holds the rolled up play surface. Again, very important that all the magnets are in correct orientation so it would hold the rolled up play surface closed.Glue all the white inlays to the black chess pieces, and black inlays to the white chess pieces.Allow glue to cure completely for steps 8 - 11. (epoxy ~24 hours)Glue all the play surface tiles to the main body. This part does require you to work quickly and accurately as the piece will slide around as the magnets with their orientation will want to repel away from each other. Only tackle one section at a time and not the entire play surface all at once.Glue all the magnets, and spacers for all chess and checker pieces. Again, all the magnets must be in correct orientation so they would stay in place on the board, and they would stack on top of each other. See below for cut away view of the pieces.                Allow glue to cure completely for steps 13 and 14. (epoxy ~ 24 hours)Get a friend and play a few matches :)Additional considerations / tips:I used a metal (ferrous metal) ruler to hold all the correctly oriented magnets just before I needed them for glue up process. I've even use a black permanent marker to mark the one side so I alway know which orientation the magnets.Use just enough glue during the glue up process. The design have relatively tight tolerances, and any excess glue may cause the tiles or pieces not fit or sit properly.The syringe style epoxy is difficult to control the amount of resin and hardener. The syringe never pushes out the same amount. I went with individual bottle epoxy resin and hardener instead.I used toothpicks to apply epoxy to all the pieces. This is slower but much more precise. I used coffee wooden mixing sticks to apply epoxy play surface tiles.The little notch you see in the design are air and glue vents to allow air to escape or excess glue to flow to.When gluing up the play surface: Work in sections instead of attempting the entire play surface all at once. Needle nose tweezers will help with the gluing process of the inlays.Lastly….The chess piece can be elevated by stacking on top of a checker piece to signify its promotion. The tongue and groove design allows the chess piece to stack on top of a checker piece neatly, and shouldn't come apart during play. The same design on the checker pieces allows them to stack neatly when not in use. During a chess match, as pieces are captured, the outer edges will accommodate total of 15 pieces. Keep in mind the commercial product can be purchased for just slightly more than the total cost of this project. But what's the fun in that?Happy printing :)Updates:5/7/2023 - added 5 additional main body options with 1mm ~ 5mm rounded tips. Note that as the rounded radius increase the gap increases and the model may not be as tightly fitted model as it should. The original design is 0.2mm rounded tip which imho is adequate. The photos may be misleading. Here's a close-up photo of 0.2mm radius.  5/7/2023 - Added STL files for those with multi-color support. This will allow the printing of the tiles for each section all at once, and speed up the assembly process. 5/8/2023 - Added STL file for a single tile. Will require to print total of 60 tiles. 28 Black tiles and 32 white tiles 5/8/2023 - Added STL for chess pieces inlays for those who wish to print the inlays. Thanks to Radish's suggestion. The inlays are offset in X, Y by 0.05mm. 5/10/2023 - Due to popular demand. Smaller version added. The main body is 211.95mm x 190.32mm. The chess and checker pieces remained the same size. However, the play surface is significantly smaller.  The smaller board option uses 2 less of the 10x1.7mm magnets. So, 212 of the 10x1.7mm magnets. (thanks to for265's eagle eye for asking the great question) 5/12/2023 - Added dual color STL files for all the play surfaces and chess pieces. Note if you're printing using multi-color support. All the chess pieces will NOT require support during printing.  6/1/2023 - Added two hinge test print STL files.  Print settings:All the tolerances of this project was design to be printed using 0.4mm nozzle at 0.2mm layer height. Layer height: 0.2mmBrim: highly recommended for the main body only.Outer perimeter: 3Inner perimeter: 3Infill pattern: honeycomb Infill percentage: 25%Top layer count: 5Bottom layer count: 5Print bed: Prusa textured PEISupports settings:Checker pieces requires supports. Use “Support on build plate only” option.Main body - No supportsAll the tiles - No supportsChess pieces will require supports only if inlay option is selected. Use “Support on build plate only” option. In Prusa Slicer, if the inlay portion isn't filled in as shown here on the left. Go to the supports section and uncheck “Don't support bridges” option.                  Correct support should look like picture on the right. No supports are required if you do not plan to have inlays. Number of pieces required:King - 1 for each color.Queen - 1 for each color.Bishops - 2 for each color.Knights - 2 for each color.Rooks - 2 for each color.Pawns - 8 for each color.Checkers - 12 for each color.