Driveway Marker Clip

This is a multi purpose model. I designed it to be able to attach orange driveway marker posts (roughly 1/4" diameter rod, with reflective tape at the top - commonly found at least in the northern USA for $1-$3 in winter, sometimes year-round) to things that aren't driveways, to mark corners. However, you can use it for just about anything of similar shape and size (and if you're ok modifying one number in the CAD, you can adapt the diameter to suit other sizes too).

Unlike similar store-bought clips, this snaps on to the pole (rather than clamping), and has a square hole for a carriage bolt instead of just a screw hole. The design is for a 5/16" carriage bolt because that's what I had the right kind of, but you can adjust the CAD for a different size if you know the dimensions of the square part.

If you want to edit this to use different sized things, please see the "How I Designed This" below - I walk through each step of the design you might edit to change simple dimensions without changing the overall layout. (It's not that complicated of a model, so if you want to change more than that, you might just save time starting from scratch.)

It's a quick print, too (about 40 minutes whether I printed 1 or 2 at a time), so consider printing a test one.

Yes, the carriage bolt hole is rotated intentionally, to make it easier to print.

If you're using this for a similar purpose as me, make sure you use more than one clip per rod for sufficient rigidity in the mounting.

I'd love to see what you use this for!

Print Settings

Probably not super important.

Printer Brand:

MakerBot

Printer: 

MakerBot Replicator 2X

Rafts:

No

Supports: 

No

Resolution:

0.3mm

Infill: 

20%, cubic

Filament: Amazon Basics PET-G Black

Notes:

Pretty easy print: the carriage bolt hole is rotated 45 degrees so that you can print without supports and without even needing good bridging capabilities in your printer and setup. I used PET-G because that's what I had loaded up. Not sure if it would be too brittle in PLA, may just need to increase the clearance in the CAD. (It kind of flexes around the rod to snap on, despite not being designed to....) ABS would probably be fine too.

Print upright, no supports, and whatever adhesion works best for your printer - it's not picky, and it's pretty easy to clean even a brim from. Note that presumably due to minimum layer time and the small cross sectional area, I didn't have much difference in print time between printing over at a time and two. I have to make sure the two brims don't touch when doing a two-item print in PET-G to avoid it sticking to the nozzle and turning to spaghetti, but that's presumably just me being new to PET-G. I'd probably print them closer together if I was using ABS, but PET-G is just so sticky. (I included a Cura screenshot of the g-code preview above.)

You could use a smaller layer-thickness if you wanted it to look a little cleaner with less-prominent layer lines - that just wasn't very important to me in the particular usage I had in mind.

How I Designed This

Modeled in SolveSpace, a free and open source cross-platform CAD package (there's even a prototype browser version) - my favorite for anything that doesn't need a lot of chamfer or fillets (for which I'd use FreeCAD) and that isn't very "generated-looking" or repetitive (for which I might use OpenSCAD, or might still use SolveSpace).

It's a pretty cool tool and worth a look - I put the screenshots together below to show how to modify this, but it actually shows most of the creation process. You can see the rest just by opening up the file in SolveSpace. Might be a nice introduction to this type of "constraint-based" modeling tool.

If you want to edit it: you'll only need to adjust dimensions shown in the screenshots below. Just move the radio button "back in time" on the layers to find dimensions/constraints to edit.

The model is designed in inches because I have inch fasteners, but SolveSpace exports everything in mm automatically so printing is easy. You can switch which one you're using in the UI at any time.

First sketch group (g002): rod diameter and clearance

Second sketch group (g003): The general profile of the part. (driven by first sketch group)

I chose the thickness to match the thickness/depth of the square part of my carriage bolt. You could probably leave it a little thicker than the square part of the bolt. But, if you make it thinner than that, you'll have a hard time attaching it since the square of the bolt will push in to whatever you're fastening it to, rather than being entirely within the plastic part.

In the next sketch, you'll see that it has been extruded - I constraint the height to match the width of the flat part of the model, whatever it gets set to in this sketch (0.850 above). Make sure that's not smaller than the diameter of your bolt head.

Third sketch group (g005 - after extruding profile so the flat part is square): Bolt hole dimension (automatically centered on the square formed by extruded profile)

The dimension shown is the side-length of the square part of the carriage bolt, plus some clearance - it's not the nominal size of the bolt!

Note: If you edit the bolt hole, you'll want to manually add some clearance in the model, I didn't do it fancy enough to automatically add clearance. (I did go back and edit the first sketch group to specify rod size and clearance separately there.)

Last group: extrudes the bolt hole sketch through the part (automatically adjusting if you change thickness)

Category: Outdoor & Garden