{"product_id":"banjitar","title":"Banjitar","description":"\u003cfigure class=\"media\"\u003e\u003c\/figure\u003e\u003cp\u003e\u003ca target=\"_blank\" href=\"https:\/\/youtu.be\/JkbQXEPkYPM?si=GSxryVgoJOeITYNp\" rel=\"nofollow noopener\"\u003eBanjitar video\u003c\/a\u003e\u003cbr\u003e \u003c\/p\u003e\u003cp\u003eThis banjitar is actually more of a banjo-shaped guitar, in that the sound board is braced to resonate like a guitar, rather than having a banjo-like membrane. It actually sounds most like a resonator guitar. The video above has an explanation of the design choices and features. It has a 22 ¾\" scale, designed to just fit on an X1\/P1\/A1 printer bed.\u003c\/p\u003e\u003cp\u003e \u003c\/p\u003e\u003cp\u003eThis project is a little involved and does require some modest luthier skills, like for installing frets in the fingerboard. It also requires some gluing using both epoxy and superglue. The additional parts needed are:\u003c\/p\u003e\u003cp\u003e \u003c\/p\u003e\u003cp\u003eTuners (10mm hole, 3R, 3L)\u003c\/p\u003e\u003cp\u003eFretwire (about 5 ft), medium height, medium width\u003c\/p\u003e\u003cp\u003e6-32 x 5\/8\" socket cap screws (18)\u003c\/p\u003e\u003cp\u003e10-32 x 5\/8\" socket cap screws (2)\u003c\/p\u003e\u003cp\u003e8-32 x 1.4\" screws (2)\u003c\/p\u003e\u003cp\u003e8-32 nuts (2)\u003c\/p\u003e\u003cp\u003eSprings: 7\/16\" OD x 1\" L x 0.047\" wire dia. – Century C-630 (2)\u003c\/p\u003e\u003cp\u003eSteel truss rod - ½\" square steel tube x 26.840\" long\u003c\/p\u003e\u003cp\u003eLight guitar strings (don't go heavier than 12 - 53)\u003c\/p\u003e\u003cp\u003e \u003c\/p\u003e\u003cp\u003e\u003cstrong\u003ePrinting\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eThe body, back neck and bridge should all be printed using PLA-CF for stiffness. Do not use generic PLA-CF as many brands are actually weaker and less stiff than standard PLA. Check the technical data sheet for Bambu's PLA-CF and use something comparable. The fretboard should be printed using standard PLA as it will have a little more give for installing the frets.\u003c\/p\u003e\u003cp\u003e \u003c\/p\u003e\u003cp\u003eI highly recommend using the 3MF file setting provided and some of the prints are complex multi-part affairs with specific settings. For example, the triangular bracing on the underside of the sound board is actually a separate part printed only as infill (no perimeters, top or bottom layers). Note that there are multiple 3MF files for all the parts as I was printing parts on different printers.\u003c\/p\u003e\u003cp\u003e \u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eAssembly\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003eFirst test fit the truss rod in the square holes in the upper and lower portions of the neck. Use a small file if necessary to scrape away any raggedy bits from the top of the holes. Slide the truss rod into the head section of the neck using a little superglue as you go to lock it in place. You don't need a lot of glue as it should already be a snug fit.\u003c\/p\u003e\u003cp\u003e \u003c\/p\u003e\u003cp\u003eNext, mix up some 1 hour epoxy and apply it to the mating surfaces on the two neck parts. Slide the heel part of the neck onto the truss rod (with a little superglue as you go) and squish the two neck pieces together. Use isopropyl alcohol to wipe away the ooze-out at the joint.\u003c\/p\u003e\u003cp\u003e \u003c\/p\u003e\u003cp\u003eSand smooth the surface of the headstock where the head plate goes - it usually comes out a little raggedy from the printing. Then epoxy the head plate in place. You can use the tuners as alignment pins to keep the plate registered with the head stock. Clamp with rubber bands or masking tape.\u003c\/p\u003e\u003cp\u003e \u003c\/p\u003e\u003cp\u003eCut, dress and insert your frets into the lower and upper ends of the fretboard, doing all but the 12th fret. Connect the upper and lower ends at the dovetail joint to lock the two ends together. Gently flip over the the whole fretboard and squirt some epoxy into the dovetail joint on the back side. Wipe off any excess that oozes through to the front.\u003c\/p\u003e\u003cp\u003e \u003c\/p\u003e\u003cp\u003eEpoxy the fretboard to the neck so that it butts up against the lip of the head plate. I recommend using rubber bands so that you can wipe away the excess ooze-out. When the epoxy has cures, level your frets and do any final dressing.\u003c\/p\u003e\u003cp\u003e \u003c\/p\u003e\u003cp\u003eUse a 6-32 tap to tap all 18 holes where the back screws onto the body. Also use a 10-32 tap to thread the holes for the screws that clamp the truss rod extension to the body. Slide the end of the truss rod into the body so that it seats all the way against the bottom of the hole at the tail of the banjitar. Use two10-32 screws to secure the body to the truss rod. (There should be no gap between the body and the neck.) Do not over-tighten these screws, as you will crack the plastic.\u003c\/p\u003e\u003cp\u003e \u003c\/p\u003e\u003cp\u003eWith the back cover, superglue the two 8-32 nuts into the pockets on the inside surface. Thread the two 8-32 screws into the nuts.\u003c\/p\u003e\u003cp\u003e \u003c\/p\u003e\u003cp\u003ePlace the banjitar face down and then place your two springs on the nubs on the underside of the sound board. Place the nubs on the spring pusher piece over the other ends of the springs. Lower the back onto the body, making sure the 8-32 screws both slide into the holes on the spring pusher piece. Then screw the back in place with the 18 6-32 screws.\u003c\/p\u003e\u003cp\u003e \u003c\/p\u003e\u003cp\u003eInstall your tuners in the headstock. The tuners will have a single screw hole in the protruding flange to keep the tuners from rotating. The location of the hole is non-standard, you will need to align the tuners and then drill a small pilot hole for the tiny screws included with the tuners.\u003c\/p\u003e\u003cp\u003e \u003c\/p\u003e\u003cp\u003eYou are now ready to string up the guitar. This is an incremental process because as you add strings and bring them up to tension, they will press down on the sound board deforming it inward. You'll then need to use the 8-32 jack screws on the back of the body to push the sound board back up to keep it flat. There is some danger that the pressure from all 6 strings at full tension would crack the sound board if there weren't the balancing pressure from the springs on the other side. \u003cstrong\u003eTherefore, you will need to incrementally adjust the jack screws to add pressure from the inside as you add strings and bring them up to tension. \u003c\/strong\u003eNote that you don't want to screw the screw in to far so that the springs go solid as this will completely destroy the tone.\u003c\/p\u003e\u003cp\u003e \u003c\/p\u003e\u003cp\u003eStart by adding the low-E string, inserting it into the hole at the tail of the body and up into the tuner. As you add tension, you will be able to slide the bridge under the string and have it held in place. Note that the bridge is compensated. The distance from the zero fret to the low-E should be 22.815\", and for the high-E string should be 22.704\". Keep adding strings and adjusting the jack screws as you go.\u003c\/p\u003e\u003cp\u003e \u003c\/p\u003e\u003cp\u003eWhen everything is tensioned up, you can use your guitar tuner to tweak the bridge position. Play an open note on the high-E string and then play y the same note (up an octave) at the 12th fret. Slide the bridge up or down until both register as E. Do the same for the low-E.\u003c\/p\u003e\u003cp\u003e \u003c\/p\u003e\u003cp\u003eWith any luck, your action will be reasonable and you are ready to play. If the action is off by only a little (\u0026lt;0.025\") high or low, you can use the jack screws on the back actually flex the soundboard up or down to fine tune the action. If the action is off by more than that, reprint the bridge scaled up or down in the Z direction to get in the right ballpark.\u003c\/p\u003e\u003cp\u003e \u003c\/p\u003e\u003cp\u003eLastly, as mentioned in the video, I have mine tuned up ½ step (the equivalent of capo-ing a standard guitar at the 1st fret). This keeps the string tension much closer to the tension they were designed for.\u003c\/p\u003e\u003cp\u003e \u003c\/p\u003e\u003cp\u003e \u003c\/p\u003e\u003cp\u003eDesign by LoboCNC on MakerWorld (license: BY-SA).\u003c\/p\u003e","brand":"Mymadmanlab","offers":[{"title":"Default Title","offer_id":67367357940016,"sku":null,"price":31.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0987\/0809\/5280\/files\/0_7771acbe-5316-4449-af61-b2593be4c9dc.png?v=1784013505","url":"https:\/\/mymadmanlab.com\/products\/banjitar","provider":"Mymadmanlab.com","version":"1.0","type":"link"}