Slowly working on the next version of the UHV.
So 3D printed out the final design, then with a few detail changes, upgraded the design on CAD and removed all the machined features, added machining allowance. Used 1.5 deg of draft on all vertical faces. From this, created an .stl file, sent that thru to the slicer programme (Cura 4.6 in my case) and then allowed a scale up (1.2%) to allow for shrinkage. The slicer creates a .gcode file that is used by the 3D printer. What was printed out was the pattern to create a sand mould.
Yesterday I smoothed the pattern and went over it a few times with spray putty. At this point, I came to the conclusion as to why Neil makes so many patterns. It is the beautiful cellulose smell that comes off the spray putty when sanding. Almost therapeutic.
Today I made the first sand mould. Will have to surround it a bit more as it is too close to the edge of the cavity. The patterns has a projection that makes the pattern take up more space. The reason for the projection is that when I turn the sparkplug boss & thread, I can put it into a 3 jaw chuck and the boss will be on centre. After machining it will be cut off.
Hours of fun.
I think Wob was scathing of Dr Joe as he ripped off Yamaha with a design of a cylinder head shape (full diametral bathtub ???) that was a dud. Without history, good or bad, we wouldn't be here now.
Wil, I haven't tried lost PLA, but do have some filament which should be a lot better. It's called Polycast. We did a design of a head shell, but haven't cast it yet, another backburner project.
"Success is the ability to go from one failure to another with no loss of enthusiasm.”
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