Friday, October 30, 2015

Thingiverse Reviews: #414556 3D-Printed Screw-In Front Lenscaps

Welcome to this week's edition of Thingiverse Reviews! Today, we'll be looking at one of the latest prints I tried out- the 3D-Printed Screw-In Front Lenscaps by profhankd. Pictured here is one of the lenscaps that I printed, attached to the lens of my camera. 

I've needed a good-quality camera lens cap for this camera for quite a while:

And it occurred to me that I could 3D-print one... so I grabbed profhankd's file and set to work.

This design, unlike the previous designs I've covered, uses Thingiverse's Customizer (OpenSCAD) format. This means that you can select the dimensions, text, and other info online, and a custom part will be generated. Here's what the Customizer format looks like for another Thingiverse product (tkbletsc's Hall Effect Tachometer):

However, the Customizer format, behind the scenes, is just an interface for variables in an OpenSCAD file.

When we open up the screwcap20140801.scad file from this Thing, we can see the variables that influence the exported STL.

// What is the filter major diameter (size)?
cap_diameter = 580; // [240:24mm,250:25mm,270:27mm,300:30mm.305:30.5mm,340:34mm,355:35.5mm,365:36.5mm,370:37mm,375:37.5mm,390:39mm,405:40.5mm,430:43mm,460:46mm,480:48mm,490:49mm,520:52mm,530:53mm,550:55mm,580:58mm,620:62mm,670:67mm,720:72mm,770:77mm,820:82mm,860:86mm (86M or 86C),940:94mm (94C),950:95mm (95C),1050:105mm (105C),1070:107mm (107 or 107C),1100:110mm,1120:112mm,1125:112.5mm,1250:125mm (125C),1270:127mm,1380:138mm,1450:145mm]

// What is the filter thread pitch?
cap_pitch = 75; // [50:Fine 0.5mm, 75:Standard 0.75mm, 100:Coarse 1.0mm, 150:Very coarse 1.5mm]

// Tolerance to allow for inaccurate filament placement (usually extrusion diameter/2), in microns?
cap_tolerance = 125; // [0:500]

// How thick do you want the cap grip to be, in microns?  Thicker uses more material, but feels nicer and can accept labels on both sides.
cap_thick = 3000; // [1000:5000]

// How do you want the cap labeled?
cap_label_position = "no"; // [no:No markings, inside:Size on the inside, outside:Size on the outside,both:Size on the inside and name on the outside]

Pretty straightforward. These variables change how the 3D file is generated, which determines the lens cap's shape. I put in a cap_diameter of 580 (58mm), a cap_pitch of 75 (Standard 0.75mm), a cap_tolerance of 125 (given that my extrusion diameter is 400 microns, I went for the value of 125), a cap thickness of 3000 (3 mm), and no label.

I exported the STL and then created a gcode file, choosing pretty conservative Slic3r settings. Favoring quality over speed, I created a gcode file that would take a while (3 hours), but would result in a more polished print. I chose an infill of 40%, which will make the lens cap light, but also strong.

The first infilled layers printing.

More progress...

Nearly done.

The completed lens cap.

The lens cap printed quite well- it was sturdy, there were no artifacts, and the threads looked great.

Installed on the camera. There are some markings left on the bottom of the lens due to the tape that  I used on the bed. No matter- I wanted to test the lens cap out first, and sand the marks off later.

I'd say there were really no problems with this print! The cap is easy to screw in, sturdy, and the threads work surprisingly well. I was expecting more of a "loose" fit, but the cap does stay in quite nicely and it feels like it won't come out.

I also really liked the ridges on the edges of the cap- they provide a nice, grippy surface for screwing and unscrewing the cap, and they look great too.

The problem with Customizer prints like this one, though, is that I can't really say whether the other versions of this file make good prints or not. Will the 45 mm cap work as well as this one? I don't know. But I can say with confidence that the 58 mm cap is great.

That's it for lens caps... looking forward to the new post next week! We've got new projects coming up!