Printing the Prusa Face Shield

This is to maybe help some printing them faster. To share what we learned. The mask is at the narrowest point 2.4mm thick that is why prusa recommends to do 3 perimeters (3*.4 = 1.2 and that *2 = 2.4) So with any nozzle you have up to 2x is width that you can relieably print so first establish your max extrusion rate as mike did in a recent video or I outline in my tutorial here https://grabcad.com/martin.pirringer-2/tutorials read the one on Volumetric E and the one on bigger nozzles if you have a choice of nozzles. If you use Prusa Slicer/Slic3r just enter that max Volumetric E in the apropriate fields and you are done. Next calculate the layer height apropriate for your printer with most it should be a multiple of .040mm and keep it between 40-60% of nozzle diameter. Then take a layer width where you can get to 1.2 mm so

.4/.5 nozzle Layerheight .24-.32 (tested on PLA) #perimeters 2 Perimeter width either .6 on all Perimeters or we got one running .48 outside perimeters, .72 inside perimeters. 0.8 on infill
.7/.8 nozzle layer height .4mm (tested HIPS) Perimeter width 1.2 on all. #perimeters 1.
we have no one with a .6 but I might be tempted to run the .8 profile with a .36 layer height

If you do not use prusa slicer take your max Vol E and divide by (perimeter width * layer height) And make sure it does not exceed what your printer can handle. Like if its 60 that your printer can handle then the max speed you set is 60 even if the above equation gives you 80 or 100.

One problem we ran into that as those parts are rather thin sometimes with some material one warped up a little at some point so we added a Brim – the brim is a pain especially on the pegs in the front so I broke out inventor and put “lillipads” at some locations. As you have camfers in the design and with printing with a .8 and 1.2mm layer width a lot of them just had 1 bead making contact with buildplate and on occasion the Nozzle left a little retraction tab and on layer 2 it pulled it off the plate the files are called FSChiron here https://grabcad.com/library/face-shield-11 The files are called FSChiron and the x2,x3,x6 is just how many I combined both print the top and bottom in one shot here is some pics
This is after 2 layers

And this is about 5ish hours later when finished 2
With the print popped off . Those 14mm liily pads are quite easy to remove.

If you want to Help check for details on how at www.vernonrobotics.com

Prushashlisha FRC team 1989 2020 build season pics

Our Season has ben canceled due to COVID-19 so I figured I make a post about our robot that we printed on our 2 Anycubic Chirons. But first some info. The team decided to name the robot Prushashlisha probably cause that is what it sounds like when I say Prusa Slicer which is the software we use to turn our inventor generated STL’s into gcode to print it. Our goal was to have our robot shoot and climb and we pretty much achieved those goals even though – unfortunately – not battle tested. And there are ongoing improvements. So without further ado…

First test with the shooter mounted to the robot
First climb test – at that time without limit switches
GT2 3d printed pulley next to aluminum one – 3DP so we can have custom sizes
Ball intake with 3DP 2.5in Mecanum wheels
View at the Electronics board through the conveyor
Look down the climber at the 3dp winch powered by a Cim and toughbox mini the winch is 50mm in diameter and so is the 78 tooth GT2 pulley part of it. The GT2 belt deploys the hook the rope does the lifting
Look at one of the climbing hooks on top of the robot. Also view of 1/2in conduit to protect the cabeling
Full view of robot before adding braces and extra stiffening in case we had to play D (as we had plenty of weight left to play with
Close up at conveyor and laser cut 1/8 in aluminum plate for added stiffness and lowering center of gravity
First test hook broken to get some data and to inspect the inside to verify the quality of us printing “solid” that means as close as possible as you can come with an FDM printer to injection molding. Nice clean break with a little trailing edge due to the camfer as it should. All in all an indication that the print has great layer adhesion both vertically and horizontally
Winch with 78 thooth GT2 pulley and ratchet teeth before cleanup bench tested to hold 300lb
View at the bare frame with wheel (skateboard) 3DP HIPS and aluminum (1/2in 3/32 wall square tube) composite We later replaced the rear wheels with omni wheels
Frame pieces before assembly
One of the toughbox mini axle holders being printed (about 30% done)

Overall there is about 14 kg of HIPS in the 3DP parts. All parts have been printed with a .8 nozzle. We used a little over 40 kg of HIPS so far this season some went into prior iterations and tests and some into spare parts. We have almost a 2nd robot in spare parts – at least regarding the plastic pieces. The whole robot without bumpers and battery currently weighs 116 lb. all the inventor files and STLs are at https://grabcad.com/library/frc1989-infinite-recharge-1 . Also check out the tutorials in regards to dialing in filaments and selecting nozzles at https://workbench.grabcad.com/martin.pirringer-2/tutorials

The Prusa slicer config file is in the root “infinite recharge” root at the above grabcad link