D-Carve, a Different Printed CNC

thingiverse

This is almost a full redesign of the X-Carve CNC from Inventables (https://www.inventables.com/technologies/x-carve) that uses only printed parts, off-the shelf components and usual V-Slot (not Makerslide or anything special). It should use the same software and have similar capabilities. Apart from the printed parts and easily available parts like bolts and nuts, you will need: 20x20 V-Slot rail - two pieces, length as desired for the X axis; 40x40 from the 20 series (or two 20x40) V-Slot rail - length as desired for the X axis, exactly the same as above; 20x40 V-Slot rail - two pieces, length as desired for the Y axis; 688Z bearings for XY wheels - MANY (number of wheels*2); 604Z bearings for Z carriage wheels - 8; NEMA17 stepper motors - 4 (two for the X axis, one for Y and one for Z); 5 mm shaft pulleys - 4 (two for the X axis, one for Y and one for Z); 8 mm shaft pulleys - 2 (for Z axis); ACME leadscrew and a nut for it - 1 (you can also use a simple M8 threaded rod if you edit the design, too); Timing belt - 10 cm longer than your X and Y rails are. Should match your pulleys; Looped timing belt - must match your pulleys and Z-axis motor plate. For an understanding of the assembly, please look at the original X-Carve drawings (attached here for convenience), compare them to the pictures above and the part names. They should be self-descriptive. The Z carriage mechanism of mine is different, so see notes below. UPDATE #1: Made the Z axis carriage more stable, now it does not wobble. Now the spindle is attached via four M4 screws arranged as a square 35x35 mm. Added a mount for DC and BLDC motors I am planning to test as spindles (see pics) UPDATE #2: Added a new type of carriage fot HIWIN rails, which five significantly nore stiffness; Added Dremel 300 and round router mount for both types of carriages Added tighter Z wheels and appropriate inner spacers for them Added drag chain and belt holders Machine operational, frst tests are being made! In the pics there is a creeper head milled out of styrofoam using VISUALCADCAM. Added laser line holders! First test video!https://youtu.be/rsAjviPOO2U Here the machine is making its own wasteboard. Print Settings Rafts: Doesn't Matter Supports: No Resolution: 0.5 nozzle 0.2 layer Notes: Used ABS for all parts including wheels. For the wheels you can also use Flexi or Nylon. IMPORTANT * When printing the wheels set your layer start point (in slicer) to RANDOM, this will save you from the 'bump' on one side of the wheels that will cause trouble in movement! Assembly Z Axis Carriage When everything is ready, you need to decide on what your Z axis carriage will be. I have tried two options: roller carriage like on te X-carve and a carriage based on HIWIN rails. Eventually, the roller carriage appeared to put too much load on the wheels and tended to bend. You can go with this option if you have a light-duty application (or redesign the carriage to make it longer and beefier). First, you need to cut two sides of the round ACME nut as shown in the pics to fit it into the Z carriage. Tap M3 or M4 thread int he holes, insert into the carriage and fix with screws from the other side. For the Roller carriage: Next, assemble the wheels: choose between normal 20 mm wheels and the tighter ones (my attempt to deal with the wobble that failed). Use the Z axis wheel spacer set and Z axis inner wheel spacers in the following order (starting from the screw's head): smallest spacer to decouple the head from the moving parts 604Z bearing no. 1 Inner wheel spacer The wheel itself 604Z bearing no. 2 The biggest spacer from set OPTIONAL If your carriage goes too tight, this may be due to incorrect distance between wheel centers and you need to put the middle spacer from the set to eliminate this. Carriage M4 Nylock nut Repeat four times for four wheels. Then, roll your carriage on the V-slot rail and insert the ACME rod. Turn to move further. The HIWIN variant: Get two HIWIN MGNR 9H rails and MGN9C carriages. Cut the rails if your Z axis is too small for them. Put the rails into the V-slot on two sides (YES THEY SHOULD GO INTO THE APERTURE A BIT) and add a needed amount of M3 T-nuts for V-slot (easily found on Thingiverse, see Remix Sources) to hold the M3 screws in place. Fix the HIWIN carriages to the printed one with eight M3 screws. Do not tighten the rails yet. First, roll the carriage onto them, ensure smooth movement and then tighten everything. Both options: After your carriage is in place, use two screws and a 688Z bearing to mount the pillow block. Tool Mount The two carriages have different mounting holes: 35x35 for the roller variant and 35x50 for the HIWIN variant. Use appropriate tool holders from the files given or design your own. The laser line holder is designed to hold two 12 mm diameter laser lines at 120 degrees to each other. See pic below to get an idea of how this is made: Laser line holders are mounted between the tool mount and the carriage like this, the spacing between should be 2 mm. The individual line holders are mounted on the sides, right in the 2 mm space.