5 hours and 30 minutes

HA!! and I thought 2hr 40m was sad. Doh!!

Truly. Five hours and Thirty minutes. 9:00am to 2:30pm. I was taking a break with a coffee on the couch when it finished. I had purposely reoriented the leg to print horizontally. With the toes pointing up. This meant lots and lots and lots of support branches but it also meant the print head wouldn't have to get as high as the first leg failure. The one where the knee joint didn't print.

I turned off the printer and waited for the bits to cool down. The head that pumps out the melted plastic is at 210C. The glass bed is at 50C.  It's best for the print, and my finger tips, to wait for everything to go cold. I chilled on many YouTubes.  God help me, I even watch animals now, yes, and bloody kittens.  So around 4:00pm I paused the TV and approached the cold print with the spatula. A few gentle but assertive taps and the boot lifts off the glass.

The support branches were like barnacles on a turtle's nose.  I gave them a few tentative prods then took my courage in both hands and "SNAPPED!!!" the first cluster off the boot. Oh joy, it worked. Full of confidence I proceeded to peel the branches like prickly flesh off a gooseberry.  LOOKING GOOD!  Last job.  Gentle (GENTLE!!!) pressure on the instep to release the ankle joint, which is printed "in place", i.e. inside the ankle. All I have to do is break the little follicles, the teeny wisps of plastic hair, bridging the air gap between the swivel ball and the shell surrounding it. One little crack. Two little cracks.  An Earth shattering third crack, and the foot shears off the ball.

When I printed this boot horizontally, ergo the foot vertically, the layers of plastic (the grain) wrapped around the foot, from instep to sole and back around. When the leg is printed (properly) vertically, standing on its foot, the grain run from heel to toe. MUCH STRONGER WHEN YOU HAVE TO FORCE THE FOOT DOWN ON THE ANKLE JOINT. The stress lines runs from front to back. Resisting the force pushing down onto the instep.   On my incorrectly printed leg, the stress lines run from top to bottom, in exactly the direction I was applying pressure. The force applied itself to the thinnest, weakest, stress point and sheared off the foot, giggling insanely as it did it.

Never mind AY?!?! Time to print another, right way up and hope for the best. The first one (vertical) started at 5:00am and failed at 7:30am.  Hopefully I will start this second vertical attempt by 5:00pm (in 20 minutes) and it will work and finish around 8:00pm.
It's a good job I'm brain dead and depressed  or I might be getting quite disheartened with this 3D print thing.

Look at the image and you can see where the foot sheared off the ankle.  Just when the knee joint worked.  Shame.  In the background is a rose that took two hours, 10:30pm to 12:30am(!).  Printed to see if I could and to test the ability of the printer to print interlocking shapes with internal air gaps.  So cool!  Just when you think every thing is going so well............

The 'Feature image' up top shows the two leg prints side by side.  The one with the foot was the first failure, it has no knee, looks like it was hacked off when a train ran over it.  It's companion is the second attempt, with a perfect knee but a broken ankle.  See the hole where a foot should be.

Leave a Reply

Your email address will not be published. Required fields are marked *

Scroll to top