Track for string, in process:
Track onto which string will be woven onto. For now movement in the y direction will be done manually. Need to figure out how to attach to CNC and then add counter weight.
Track # 2 MDF plate with holes for wire.
Track # (1 too much friction) sanded wood, too thin for keeping balance.
CNC for CNC:
The left image shows the tool paths created in Rhino Cam to mill out the arm attachment for our cnc, the right image shows the mill in action. The arm attachment was milled out of 3/4″ plywood.
The top left image shows the arm after the roughing pass. The finishing pass was not completed because all of the stock material was removed by the roughing pass, so the band saw was used to clean up the model. The two other images show how we intend to place the arm on the cnc, with a second piece connected to the arm by string. Further experiments with dunking in wax with the arm are to come.
First sketches thinking through arm concept. Is it a rubber band or string that when stretched pull together hinge sitting on a track that is attached to model. This way it pulls it close together or apart.
Ideas for further:
To reintroduce water: have a second stepper motor driving dipping material horizontally. Will need to sync both motors or not…
So we made a lasercut file that screwed into the CNC and allowed to tie in a spring.
Pin run through wooden dowel to keep arm from sliding out. 1″ flaps are totally useless with the cardboard material.
Sketch for lasercut file. Central cutout to fit wire in. Smaller holes to tie in with wire.
Printing did not work.Tried changing flow, retraction, etc. Will try using Simplify instead of Cura.
These prints are of the Fusion jig made below. Starting with the 2nd base plate and the spring + holder.
Left: Changed flow. Extrusion was uneven (makes sense). So as you can see in the right images I increased flow back to 100 but thought increasing first layer speed would make filament distribution better. It was slightly but nozzle head started eating away from filament. First layer also did not fully extrude. Middle (increased mm of retraction).
Left: Standard settings from instructional PDF of Lulzbot. Played with layer height width of first layer. Issue: extrusion was too much making second nozzle jump/run through and peel part of filament from bed.
Here I looked at how a spring mechanism could be attached to the arm. I thought of a holder that fit into a spring with a pin hole to lock arm into. I did not change much of the coil dimensions. Set to section size: 0.3 in, height : 3 in, D: 1.2 in, Revolutions: 11. There are several threaded holes for screwing into CNC.
Left: holder/spring jig in Fusion. Bottom plate: 1″ flaps to grab onto CNC for extra security (meant for basswood/plywood). Right: Inspiration for fitting part into spring.
What if you had a secondary motor attached to arm that flips after each lift.
What other materials can we use? (Coiled wire).
Sketch of how attachment should hold onto CNC. Looked at how spring may connect to arm/pole holding dunking object. To print a spring with holder attachment inside. Along with a pin an hold to hold it tother. Bracing of CNC will be needed when turned vertical.
Here are earlier sketches where I thought out how to assemble different components and hold arm in place.
Using the CNC as a base, first thought was to add a ball joint to introduce a secondary motion that was random or at least not controlled but the machine. Second idea was to replace ball joint with a spring (s) for a strong connection and a bouncier effect on the rotation. This would hopefully affect how the wax or other dunking material performs when elevated.