Tag: Gardening

Growing and sometimes fixing

Deer Fence Hangers

For what should be obvious reasons, we armored Mary’s “kitchen garden” with buried concrete blocks and deer fence. I secured the fence to 7 foot plastic-coated steel-core posts strapped to shorter stakes supporting the lower wire fence, using cable ties we both knew wouldn’t survive exposure to the sun.

As part of the spring garden prep, I summoned proper supports from the vasty digital deep:

Deer Fence Hanger - Build view — Deer Fence Hanger – Build view

The general idea is to plunk one atop each post and ~~tangle~~ wrap the netting through the hooks, thusly:

Deer Fence Hanger - installed — Deer Fence Hanger – installed

The garden looks like we killed an entire chess set and impaled their carcasses as a warning to others of their kind, but the fence now hangs neatly from the top of the posts rather than drooping sadly.

Each one of those things takes nigh onto two hours to emerge from the M2, so I printed them one by one over the course of a few days while making continuous product improvements.

The “natural” PETG isn’t UV stabilized, either, but it ought to last longer than those little bitty nylon cable ties. We shall see.

The OpenSCAD source code as a GitHub Gist:

	// Deer Fence Hangers
	// Ed Nisley KE4ZNU May 2021

	Layout = "Show"; // [Build, Show, Cap, Hook]

	// net grid spacing
	NetOC = 55.0; // [40.0:5.0:70.0]

	// stake OD
	PoleDia = 23.0; // [20.0:30.0]

	//- Extrusion parameters must match reality!

	/* [Hidden] */

	ThreadThick = 0.25;
	ThreadWidth = 0.40;

	HoleWindage = 0.2;

	Protrusion = 0.1; // make holes end cleanly

	inch = 25.4;

	ID = 0;
	OD = 1;
	LENGTH = 2;

	function IntegerMultiple(Size,Unit) = Unit * ceil(Size / Unit);

	//———————-
	// Dimensions

	Notch = 5.0; // hook engagement

	WallThick = 3.0; // min wall and end thickness

	Shell = [PoleDia,PoleDia + 2WallThick,NetOC + 2Notch];

	HookBlock = [10.0,Shell.y/4,2*Notch]; // hanger inside length

	LegendBlock = [0.7Shell.z,Shell.y/2,2ThreadThick]; // legend size

	//———————-
	// Useful routines

	module PolyCyl(Dia,Height,ForceSides=0) { // based on nophead's polyholes

	Sides = (ForceSides != 0) ? ForceSides : (ceil(Dia) + 2);

	FixDia = Dia / cos(180/Sides);

	cylinder(r=(FixDia + HoleWindage)/2,
	h=Height,
	$fn=Sides);
	}

	//———————-
	// Pieces

	module Hook() {

	//%Cap();
	translate([Shell[OD]/2 – Protrusion,HookBlock.y/2,0])
	rotate([90,0,0])
	linear_extrude(height=HookBlock.y)
	difference() {
	scale([1,2])
	intersection() {
	circle(r=HookBlock.x);
	square(HookBlock.x,center=false);
	}
	square(Notch,center=false);
	}
	}

	module Cap() {

	difference() {
	rotate(180/6)
	PolyCyl(Shell[OD],Shell[LENGTH],6);
	translate([0,0,-WallThick])
	rotate(180/24)
	PolyCyl(Shell[ID],Shell[LENGTH],24);
	translate([-Shell[OD]/2,0,Shell[LENGTH]/2])
	rotate([0,90,0])
	cube(LegendBlock,center=true);
	}
	translate([-(Shell[OD]/2 – LegendBlock.z/2),0,Shell[LENGTH]/2])
	rotate([0,-90,0])
	resize(0.8*LegendBlock,auto=[true,true,false])
	linear_extrude(height=LegendBlock.z)
	text(text=str(NetOC," ",PoleDia),
	size=6,spacing=1.00,font="Bitstream Vera Sans:style=Bold",
	halign="center",valign="center");

	}

	module Hanger() {

	Cap();
	for (k=[0,1])
	translate([0,0,k*Shell.z])
	for (a=[-1:1])
	rotate([k180,0,a60])
	Hook();


	}

	//———————-
	// Build it

	if (Layout == "Cap")
	Cap();

	if (Layout == "Hook")
	Hook();

	if (Layout == "Show")
	Hanger();

	if (Layout == "Build")
	translate([0,0,Shell[LENGTH]])
	rotate([180,0,0])
	Hanger();

view raw Deer Fence Hanger.scad hosted with ❤ by GitHub

2021-05-19

Bypass Lopper Bumper

I used the long-handled bypass lopper to harvest the 3D printed soaker hose splices and clamps, which made the sad state of the lopper’s bumper painfully obvious:

Bypass Lopper – OEM bumper

Contrary to what you might think, those rivets never had a head on this side and the bumper seems to be held in place by an interference fit with the plastic handle cover.

A bit of cutoff wheel work removed the crimped end on the 5 mm stud holding the bumper to the pot-metal dingus:

Bypass Lopper – shaft cut

Whacking it with a punch separated all the parts:

Bypass Lopper – bumper parts

The gray thing is a silicone rubber vibration isolator that’s a bit too large in all dimensions, but surely Close Enough™ for present purposes.

A length of 5 mm shaft became the new stud, with M3×0.5 threads tapped into both ends and a pair of random screws held in place with red Loctite:

Bypass Lopper – epoxy curing

There are no pix of the drilling and threading, as it was accomplished after a shiny-new 2.7 mm “titanium” metric drill from a not-dirt-cheap set shattered in the shaft:

Shattered metric drill

The blue color on the flutes is Sharpie to remind me it’s defunct. I completed the mission using a #36 drill with no further excitement.

The dingus is now held to the lopper with JB Weld and, should that fail, I’ll drill-n-tap the rivets and be done with it.

2021-04-10
Soaker Hose Splices: End Of Life

The soaker hoses from Mary’s garden all came from someone else and have now reached their second end of life:

Soaker Hose Splices – end of life

Those orange lumps kept them alive for a few more seasons:

Soaker Hose Splices – harvested

In the unlikely event I ever give another in-person presentation about 3D printing and what it’s good for, I’ll have some interesting show-n-tell samples. Might have to soak the dirt off, though.

2021-04-04
Vultures Sunning

Spotted after pre-season prep at Mary’s Vassar Farms garden:

Vultures sunning

It must feel really good up there atop the old barn, even if they’re sunning themselves to kill off parasites.

Taken with the Pixel 3a zoomed all the way in at 7× from a bit over 200 feet:

Vultures sunning – photo range

Then cropped and sharpened just a smidge. Not a great picture, but good enough for practical purposes; the Good Camera + Big Glass takes better pix and is too awkward to carry in my pocket.

2021-04-03
Step2 Garden Seat: Replacement Seat2

As expected, the plywood seat I put on the Step2 Garden Seat for Mary’s Vassar Farms plot lasted about a year before the wood rotted away around the screws. In the meantime, we’d acquired a stack of SiLite cafeteria trays, so we applied one to the cause of better seating:

Step2 Seat – tray variant

Various eBay listings value that slab of ~~Bakelite~~ Melamine up to $20, which is far more than Mary paid for the entire stack at a local tag sale. They also call that color “rich brown”, which is certainly better than what immediately came to mind when I saw them.

The stylin’ asymmetric design happened when I realized the squared-off handle end of the cart didn’t demand a rounded-off end of the seat. I cut off the raised tray rim before sketching the rounded outline using the rotted seat as a template; some of the sketch remains over on the right-front corner. A session with Mr Belt Sander put the remaining rim edges flush with the surface, no matter what the picture suggests.

The tray being 2 mm thinner than the plywood, I tried printing the hinges in a different orientation with different built-in support:

Rolling Cart Hinges – solid model – build

The perimeter threads pulled up far too much and, although fiddling with cooling would likely help, I think the original orientation was better:

Rolling Cart Hinges – solid model – bottom

Given that the post-apocalypse breakfast will be served on similar trays, the seat should survive for quite a while in the garden. We think the sun will convert the brown surface into a bun warmer; a coat of white paint may be in its future.

The original OpenSCAD code is still out there as a GitHub Gist.

2020-09-10
Monthly Science: Inchworms

A Rudbeckia Black-eyed-susan coneflower from the garden carried a passenger to our patio table:

Inchworm – linear

Even linearized, the inchworm was barely 20 mm long; it’s the thought that counts.

The stamens mature in concentric rings, each stamen topped by a pollen grain. Apparently, those grains are just about the most wonderful food ever, as the inchworm made its way around the ring eating each grain in succession:

Inchworm – feeding

Of course, what goes in must come out:

Inchworm – excreting

I had to brush off the table before washing it; the pellets are dry, but smear when you get them wet.

Another flower in the vase held a 10 mm inchworm with plenty of upside potential:

Inchworm – junior edition

After nearly a week, the flowers were done and the inchworms had moved on. We wish them well, although we likely won’t recognize them in the future.

2020-09-01
Round Soaker Hose Clamp

An aging round soaker hose sprang a leak large enough to gouge a crater under a tomato plant, so I conjured a short clamp from the longer round hose splints:

Soaker Hose Clamp – round – installed

The shiny stuff is the plastic backing on strips of silicone tape intended to prevent the high-pressure water from squirting through the porous 3D printed plastic. The fat drop hanging from the hose shows some leakage around the tape; an occasional drop is perfectly OK.

The leak faces the round side of the bottom half of the clamp, which probably doesn’t make any difference.

I hope the washers occupy enough of the minimal surface to render aluminum backing plates superfluous:

Soaker Hose Clamp – round – kitted

Creating the 3D model required nothing more than shortening the original splint to 30 mm with two screws along each side. While I was at it, I had Slic3r make three clamps to put two in the Garden Dedicated Hydraulic Repair Kit for later use:

Round Soaker Hose Splice – 30mm – Slic3r

Change two lines in the OpenSCAD code and it’s done.

Also: clamps for flat soaker hoses.

2020-08-21