3D Printable Component Generators

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CONFIGURABLE FIN ALIGNMENT GUIDE (UPDATE)

This is a fairly significant update to the FAG posted earlier in this thread. It includes the following updates:
  • Now allows selection of an existing body tube -or- direct entry of a tube diameter value.
  • Now has optional cutouts at the root for fillets.
  • Choice of fixed fin spacing (e.g., 6 fins gives spacings of 60 degrees) -or- you can choose irregular spacing, for those oddball models.
  • When choosing irregular spacing, you can also choose an individual fin width for each fin.
As before, this is an OpenSCAD Customizer implementation. After configuring your Fin Guide, Press F6 to render it (may take a while), then pressing F7 will export it to an .stl file for 3D printing.
2021-01-30 16_57_40-Fin Guide2.jpg
Usage is pretty much self-explanatory, and the best way to figure it out is just to play around with the slider controls a bit. See the blurb below, if you haven't used the Customizer before.

Changes in operation from the previous FAG are as follows:
  • Under 'Select Tube Diameter' select an existing tube from the dropdown list -or- set it to 'use direct entered value' and enter a diameter value with the slider or direct entry box below.
  • Under 'Guide Parameters' a slider has been added for 'Root Gap', which controls the spacing at the fin root for fillet clearance.
  • Under 'Fin Parameters' the number of regularly spaced fins is selected. Selecting '0 fins' will turn off regular spacing and use the irregular spacing. 'Fin Span' in this section controls the span of both fin types.
  • Under 'Discrete Fin Angles' is where you set the angular position of each discrete fin. Fin one is always placed at zero degrees. Unused fins are kept at zero degrees; position a new fin by changing it to a non-zero value. Up to nine fins can be positioned.
  • Under 'Discrete Fin Thickness' the thickness of each individual fin is specified. The largest thickness also needs to be set as the 'Fin Thickness' under the basic 'Fin Parameters'.
In the example pictured above, four fins of 2.1 mm thickness have been positioned at 0, 90, 180, and 270 degrees, and two smaller fins of 1.6 mm thickness are positioned at 45 and 225 degrees. How cool is that?

The attached 'Fin Guide2.TXT' file needs to be renamed to 'Fin Guide2.scad' to use it with OpenSCAD.


====================== OpenSCAD Customizer================================
This file has been created with the intention to use the OpenSCAD 'Customizer', which allows
the use of Windows-style selection tools to set parameters of the component. The use of this
feature requires the following steps:

1. You must install and use the OpenScad 'Development Snapshot' version, available at:
https://www.openscad.org/downloads.html
Scroll down to Development Snapshots, use version OperSCAD 2018.09.05 or later.

2. Open the 'Fin Guide2.scad' file with OpenSCAD.

3. In the OpenSCAD [Edit] menu, select [Preferences] then open tab [Features], check
[Customizer], then close the window when the check is shown.

4. In the OpenSCAD [View] menu, uncheck the option [Hide Customizer]. The Customizer
window should open at the right side of the screen.

5. At the top of the Customizer window, check 'Automatic Preview' and select 'Show Details'
in the dropdown box.

6. If you are comfortable with the instructions above, then also in the [View] menu, you can
check the option [Hide editor], which will allow the full screen to view the model. You
can also check to [Hide Console].
 

Attachments

  • Fin Guide2.txt
    13.7 KB · Views: 17
Last edited:
I 3D printed this yesterday. The idea was to align the motor tube to the body tube axially as well as vertically, in conjunction with a Guillotine Fin Jig, while I tacked them to the body tube. Per one of John Coker's videos the aft centering ring was left off to facilitate epoxing the fin to the motor tube and inside of the body tube. If nothing else it gave me peace of mind to know that the fins were locked down on all three axis'.

The large end could be smaller but it makes it easier to remove. It's for a LOC IV. I printed one for the LOC Graduator too.
 

Attachments

  • LOC IV Fin Alignment Jig v3.stl
    200.8 KB · Views: 8
FWIW there is a new 2021 version of OpenSCAD available. It looks like the most significant changes are to the embedded code editor, perhaps enough that I'll start using it rather than an external editor. Autocomplete, Calltips, Code Snippets, and Tabbed Windows will be nice, and the Jump-to-Code could be an excellent help. I don't know yet if the new version changes the use of any of my tools - please let me know if problems show up.

Details are here. Downloads are here.
 
View attachment 365616 CONFIGURABLE TUBE DRILL GUIDE



You say it there, it comes out here...

A printed drill guide can be a simple thing to do a one-off, but doing it as a configurable item, I had to add some whistles and bells. The drill guide presented here as an OpenSCAD Customizer item incorporates the following features:

1. Variable from 1-12 radial drill holes.

2. Tube size selectable from a menu of standard tube sizes (with a factor for fine adjustment).

3. Adjustable length and diameter of the guide body.

4. Drill size selectable from a menu of fractional-inch drills in 1/32 inch increments. While printed holes (especially small ones) are often undersized, there is no provision for adjusting the size, 'cause hey, you're going to run a drill through them anyway. Right?

5. At each radial position, up to three drills can be placed in a longitudinal line, independently positionable on the guide.

6. Optional, adjustable size slots that can be used, for example, with a piece of aluminum angle to align multiple guides on a tube.

7. Optional, adjustable size flange that should be useful to tape or clamp the guide to the tube.

8. Optional slots in the tape flange that can be used to visually align the guide to a mark(s) on the tube.


Usage is pretty much self-explanatory, and the best way to figure it out is just to play around with the slider controls a bit. See the blurb in the source code header (or earlier in this thread) for details on how to set-up the OpenSCAD Customizer.

Note that the attached .txt file needs to be renamed to the extension .scad to be opened by OpenSCAD.

Gary A. Crowell Sr. (vcp)

I had some issues using the drill guide generator this weekend. I tried to print a 3.1" diameter guide with three 3/16" holes and the generator just produced a sphere. Am I missing something?

Regardless, it's not that big of a deal. I was excited about using this component generator, but I just whipped something up in Tinkercad that did the trick.
 
It looks like it's too late to delete the above standoff posts, but the following replaces them. Everything that they did is incorporated into this one. As before, read the instructions in earlier posts on how to use the OpenSCAD Customizer, and, the attached file must be changed from the extension .TXT to .SCAD (scad file uploads aren't allowed here). Once you get past that, easy to use;

This one adds a variable slanted aft deck, base extension to the tube, elliptical fore-aft base extension, and a rail button recess; all configurable of course.

CONFIGURABLE AERODYNAMIC RAIL BUTTON STANDOFFS

View attachment 376543

As before, read the instructions in earlier posts on how to use the OpenSCAD Customizer, and, the attached file must be changed from the extension .TXT to .SCAD (scad file uploads aren't allowed here). Once you get past that, easy to use;

The Rail Button Standoff is defined by:
  • The diameter of the tube it conformally fits.
    • Common body tube sizes between BT20 and 98mm are available.
  • The standoff height, above the surface of the body tube. (Note that this is the height at which the button sits, even if it is recessed.)
  • The diameter of the standoff base, at the surface of the body tube.
  • The diameter of the top of the standoff, i.e., at the base of the rail button.
  • The diameter of the drill/screw hole vertically through the center of the standoff.
  • Depending upon the speed of your computer, you might want to start with a low smoothness level, like 60. Once you have the shape you want, increase the smoothness to 200 or more, but it might take ~30 seconds to render the final shape.
  • A conical or aerodynamic standoff is selected by the AeroButton checkbox.
  • The AeroFactor setting determines the length of the 'tail'.
  • The AftSlant setting slants the 'deck' aft of the standoff downwards for a more aerodynamic shape. (I wish it could be rounded better, but, another time.)
  • The Standoff Base Extension extends the base of the standoff down to meet the tube, to avoid a vertical edge at the base. This does not affect the standoff height.
  • The Standoff Base Elliptical factor extends the base of the standoff fore and aft without increasing its width.
  • Rail Button Recess allows the base of the rail button to be recessed into the top of the standoff. Recess Diameter is the diameter of the cavity, which should be smaller than the top of the standoff.
  • Rail Button Recess Depth is how far the button is recessed into the top of the standoff. Note that the bottom of the recess is at the standoff height.
I'd like to use this for one of my upcoming projects, but 54mm tubing isn't an option for the tube size. I would suggest just making that a completely user defined field, or at least make it an option.
 
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