Voronoi shoe rack

“this whole thing is a shoe rack…but not a real shoe rack, more like a freaky shoe rack”

We had a pile of shoes that needed sorting out.

So I made a shoe rack. I wanted some kind of lattice cut-outs in the shelves and back for easy airflow around wet and muddy shoes, but Fusion 360 isn’t the best for making such patterns. As I can’t draw for crap, I wanted a space-filling algorithm to draw a pattern for me. So, yeah, Voronoi. I know it’s a computational cliche and over-used, but wtf, it’s easy and there’s a plug-in for Fusion 360.

The material was going to be okume ply, but I ended up with okume skins on poplar ply. This has very lightly coloured edges which really showed any burning from an overheated tool. The solution was a single flute compression bit which stayed much cooler than a two flute. Top is two flute, bottom is single.

The joints are all slightly hidden tenons into dogbone mortises. The intention was to make this self-jigging. It was close, but I put the tenons in the middle of pieces, so the corners needed some clamping to get them to behave. Lesson learnt – tenons at ends as well as centres of joints.

Danish oil and rubbing with non-steel steel wool pads to finish and shoes are now organised.

Routing an elevation map of the Sounds – Pipi & Ant’s wedding present

I wanted to make a wedding present for a couple of friends who live out in the Marlborough Sounds, like way out the back, beyond tarmac and electricity and plumbing. The Sounds make for interesting maps and I’d been playing with digital elevation maps and native woods, so I made them a map, with the land from tawa and the sea from tōtara.

Their family has been there for generations. Their own maps are not digital or geographic, but social. It’s all “turn at John’s house”, or “past the spot where the person did the thing”. So having a map that’s physical, that can be touched, seemed the way to balance the digital with the real world.

First problem was finding the wood. I wanted a light wood for the land to contrast with tōtara sea. Tawa is an ideal colour, fine-grained for detail, and good to carve but getting hold of some was a challenge. It is no longer produced commercially. I had hoped to use old floor boards, but round here building recycling places can do you kauri or matai and that’s it. In the end, asking around revealed some in a shed in Rotorua (thanks, Russell). This stock also set the size, 200 mm high, less a bit for squaring off.

The limited stock meant I also had to get it right, as I had enough for three tries. This took two trials on scrap wood, one screw-up with the good wood, and the second one came out good enough.

To get from digital map to carved wood, the tool chain goes:

  1. Get the digital elevation data
  2. Turn that into a greyscale image
  3. Prepare wooden blank
  4. Carve contours
  5. Finish

 

Get the digital elevation data

Koordinates have a great interface to the LINZ height map of NZ, with 15 metre resolution across all of NZ, courtesy of the School of Surveying. It’s not the 1 metre resolution that Wellington has, but the Sounds are steep enough that this gives sufficient relief.

I don’t have fancy GIS software, so I just exported the datasets as PDFs. The resolution of the export is way below that of the datasets, but the final piece is less than 200 mm high so I worked with files around 800 pixels high.
 

Turn height data into a greyscale image

In a simple world, I’ve have just taken the greyscale from the PDF, stretched the histogram so the highest point on the map was white, the lowest was black, sent that to PhotoVCarve and be done with it.

However, I wanted the carving to hit the tōtara for the sea and the tawa for the land and that needs a clear division in carved height between the land and sea. As the greyscale value sets the height, that means a clear division in value between land and sea. The sea is zero metres height (by definition) and the land ranges from +1 to +775 for Mount Shewell. That’s going to be physically mapped into 0..19 mm of wood. Getting the zero to +1 metre contour to line up with the interface between the two woods wouldn’t happen. So I cheated, to give a large physical height step between the sea and land by artificially setting up a large value step in the image file. That step gave me some leeway to get the heights right and line up the coastline with the interface between the wood.

Using a map as a mask, I pulled out the land and tweaked the value to run from 20..255.

Reversing that mask, I pulled out the sea and set the value to zero.

Combining the two gives the greyscale image to feed into PhotoVCarve.

You can see the height step in the histogram, it’s the gap between black and everything else.


 

Prepare wooden blank

To get a good flat interface between the tawa and tōtara, I faced both in the router then clamped up the stack. I really should get a vacuum table for this.

Using Fusion 360 to generate the toolpaths, I faced off the top and cut a slot around the outside of the carved area. This is really due to a limitation of PhotoVCarve – it carves the first column of image data just the same as all the rest. That means for fine deep work, the first cut will be blind and full depth, whereas all the rest will be flank cuts. If you’re starting at the edge of a piece of work, that’s fine, but if you want a carving in the middle of a piece, then you need to cut a surrounding groove. Yes, lining up facing, grooves, and carving cuts was a pain.


 

Carve contours

PhotoVCarve has it’s quirks, but it’s the software for this.

This took a while, about four hours. Admittedly, I was using a tiny step-over of 0.2 mm.

And then cut the outer edges and part off.


 

Finishing

Straight off the router it looked pretty good. There was some minor fuzzing on some grain angles that tidied up with some scouring pad.

I used Danish oil to finish it off, but as I did, the beautiful contrast between the woods, the whole point of this palaver just vanished. The tawa turned the same colour as the tōtara. I was not happy to discover that tawa did this.

It turns out, however, that tawa is a joker. Over the next week, it turned back to that light colour. Thanks, tawa.

Final result:

And then we went to the Sounds to deliver it.

CNC routed cat tower

Andrea asked me to make a cat tower as a gift for her niece.

I might have got a bit carried away.

Version one failed user acceptance testing. This is version two.

I wanted this with no screws at all, just wood that slotted together and locked itself in place. I also wanted it to be easy and obvious to assemble correctly and impossible to assemble wrong. That part turned out ok.

 

Packs down for easy transport.

The cut-outs were generated using the Ready reaction-diffusion simulator and the Grey-Scott algorithm.

 

Ready has some weird glitches that left me scratching my head for a while but I worked out a suitable tool-path. Start with the component in Fusion 360.

Screenshot that and turn it into a bitmap mask.

Import the mask into Ready and run the simulation and tweak the parameters until it looks ok.

Take a screenshot into Gimp and simplify.

Take that image into Inkscape and trace bitmap to get paths. Save those paths as an SGV.

Insert that SVG into a sketch in Fusion 360.

Extrude to cut the component.

And then repeat for different parts with different parameters.

 

 

Andrea finished the raw ply with linseed oil to avoid anything toxic and old carpet cut out and stapled on. It was cut in cat shapes, in case anyone hasn’t worked out the theme yet.

Smoofy approves.

Router-made signs for KnowYourStuffNZ, Kakariki and Sanctuary

I’ve been making a heap of signs with the router.

Turns out my favourite technique is to mask off, cut the signage through the mask, and then spray the cut areas. This gives coloured inlaid lettering which is resistant to getting scratched when bouncing around in the back of the ute on the way to festivals.

The best guide to this technique that I’ve found comes from totrand on Youtube:

For a mask I’ve been using the self adhesive film from Bunnings. I’ve been using spray on shellac to help the mask stick to the ply and to stop paint from bleeding from the cut areas along the grain.

The tool for most of these was a 1/8 inch down cutter. I had got up to 700 metres with the first one with no visible wear before I rammed it into a clamp and snapped it off.

KnowYourStuffNZ can’t have a sign that says “test your drugs”, so I made a heap of alternatives.

They ended up all over the place.

 

And some art, in the style of Gordon Walters.

One for the Sanctuary, with lettering from Melissa Mepham. This one I did in melamine-coated chipboard. This gave great sharp edges that looked good in sunshine. I thought it might have problems with humidity from being outside. Turns out it cracked horribly. Oops. Won’t do that again.

And some for Kakariki Brewing Company at Beers at the Basin.

…and now I’ve a few more to do.

Overdoing it – drawers for the router bench

Routers need bits, not just cutting bits, but clamps, collets, spanners, t-bolts, feeler gauges, laptop, and other random crap. So I made some drawers for the crap, to fit under the router bench. This was a chance to explore relief carving, coz I’ve lots more of this to do.

Original image from Ashlyn’s dirty cup pour:

Relief carved drawer fronts:

The drawers are 1300 wide and the router will only do 1200, so the three long pieces were made up with lapped dovetail interlocking joints taken from Jochen Gross’ Fifty Digital Joints.

The other joints were simple finger tenons with dogbones for relief at the corners. I varied these enough so that all the pieces could only be assembled in the correct way. I tried a few blind mortises, but the outside of this piece is pretty hidden, so they weren’t really needed.

Tolerances. *humpf*

The goal was to have all of these pieces just push together. Testing finger joints on small pieces suggested that cutting each piece 0.2 mm undersize would do this. However, oops, small pieces are not large pieces, nor are they pieces made up of two bits of wood joined together. So yeah, there was lots of filing to make everything fit. I’d suggest 0.2 mm for small pieces, add an extra 0.1 mm for large pieces, an extra 0.1 mm for joined pieces, and an extra 0.1 mm where pieces are joining in three planes. Live and learn.

But got there in the end.

I was going to just glue these joints, but bottled it and put some screws in, just in case. It’s probably massively over-built.

I splashed out the NZ$ 200 on PhotoVCarve to turn images into toolpaths. Fusion 360 with the Image2Surface plugin will do this for free, but it’s really struggling – it can take over an hour to process. PhotoVCarve does it in seconds. Total carving time was about 13 hours, with 0.4 mm step-over and a 1/4 inch ball-nose carbide bit. The surface finish needed very mild touch-up with fine sand paper on the steepest relief, but overall, this is straight from the machine with nothing more than linseed-based priming oil.

Turned out all right in the end.

Vertigotech router – Controlling noise and dust

Routers are painfully noisy and throw dust everywhere. If I wanted that, I’d go to Burning Man (again). So:

Step 1 – Dust Shoe

Vertigo do a dust shoe to stop chips flying everywhere. They were kind enough to give this to me for free, as the magnets aren’t perfectly aligned, but it still grips well enough.

Step 2 – Dust Extraction

Dust now gets pulled into a Triton dust collector bucket by an old Dyson vacuum.

This does a reasonable job, although fitting the hose into the dust shoe requires some surgery – the shoe has to be split into two parts so the hose can feed through the hole and then be clamped in place. The shoe is acrylic, so this isn’t hard.

The hoses do pop off the connectors too easily, but it takes twenty-odd litres of dust and chips that are now not spread throughout the workshop.

Step 3 – A Cabinet

It’s still loud, so I used melamine from the shipping box and some random ply to build an enclosure. Long hinge and a wide opening, spaced double layer of acrylic for a window, big handle for the opening lid, and a port for the dust hose. There’s an air filter to let air in when the vacuum pulls it out, but given that the box isn’t that well sealed, I’m not sure this is really needed

Much quieter and the dust is under control.

Best investment was $40 on an LED strip inside the box, for excellent work lighting.

Step 4 – Spoil Board

And a thick ply board to protect the router bed from the inevitable over-cuts, with slots for clamp bolts and shallow marks for aligning stock.

Step 5 – Route ALL the things

Design from Nathan McIntyre.

New workbench

From wood left over from the house build, bolted to wall and floor, and flat and level.

Possibly making the top from three layers of 18 mm ply is overkill. Possibly not.

You know it’s been a good weekend when you have to clean the van out with a shovel.

Thanks to Joel, Wendy, Polly, Tommy, Thomas, Jodi, Will, Mike, Johanna, Walter, and Annabel. And thanks especially to Cliff and Mighty Mouse the tractor.

And as well as wood hauling, there was laying of dance floors, rigging of aerials trusses, breaking of masonry drills, weeding, marking out, crimping, general sheddery, tea, fish and chips, and company. Long weekends are hard work…

[EDIT – Now with pics!

Wood hauling day on the 12th

Okay, as everyone seemed to a) get plenty of wood, and b) enjoy themselves, there’ll be another wood hauling day planned in for Sunday, the 12th of this month.

Now that we’ve got a system sorted, I think we can get even more wood out of the gulley. Cliff the builder will be bringing the world’s cutest tractor to save the van’s clutch. With plenty of people, we can be hauling out pretty continuously.

So, who’s keen? And any suggestions for how to improve the experience for all?

Wood!

Thanks to Thomas, Kim, Will, Joel, Yvette, Yvette’s mate, Jen, E, Mike, Jodi, Polly, Wendy, Tommy, Rhiannon & Sasha for coming and taking away some of our wood. I think we managed to fill three trailers, four cars, and two vans. Also, no injuries and the only breakages were two $10 ratchet straps, which can be resewn.

Van+rope+pulleys+wool sacks worked quite nicely, once we put down the planks over the steepest parts. Big steel bars (thanks again, keptinacan) and big wooden posts and ratchet straps worked despite the soft ground.

I don’t know if it’s a Kiwi thing or a Burner thing, but everyone seemed very good at making themselves useful, at finding a role in the collective effort and contributing their own skills, whether that’s swinging an axe or making cups of tea.

I should have taken before and after pics of the pile, coz we made a serious dent in it. There’s plenty more and people seem keen, so there will be another hauling day, possibly weekend after this one? How would sunday, the 5th work for people? Or should I ask when we’re not so sore?

Onwards!

We’re still on. Weather is a tad chilly, but the site is comfortably sheltered from the wind. You may wish to bring warm clothes for when you’re standing around drinking tea.

Prep for wood hauling

I think I’ve everything ready for hauling firewood on sunday. See you all at 10 am*. Please bring barrows, axes, possibly a chainsaw if you’ve got one, safety equipment and mugs for tea.

I’d been pfaffing about with sub-millimetre engineering for too long. It was time to get some inch thick bars of steel (thanks, keptinacan) and a sledge hammer:

pic

Free firewood

OMFG we’ve got so much firewood. It’s seventy-year old pine and macrocarpa, you can’t buy wood like this. It burns beautifully, splits easily and we want to give it away for free.

This sunday, the 22nd, we’ll be up at the section in Brooklyn, trying to get rid of as much as we can. Come along and for a reasonable amount of manual labour, you’ll get lots and lots of wood. Some is split, some is sawn into chunks, some is still big rounds. We’ll haul whatever people want.

The wood is down a gulley, but I have a plan for hauling it out using wool sacks, ropes, pulleys and a big diesel engine. Last time, we used Cliff’s Holder tractor and it was pretty easy going. This time we’ll be using the van, and pulling the wood up to right by the car deck*.

All the hauling to be done by people is on the level, so wheel barrows can be used, from path direct to road.

So – who’s keen? Can you bring a barrow, an axe, a chainsaw or a wool bag? We have these, but more tools will get us more wood.

* – I hope this works, otherwise there may be scratching of heads. Coz carrying it out by hand is a bugger.

Anyway, pics from scrub cutting

House progress

After three years, we’re finally starting on the house, though by “house” I mean section, and by “starting” I mean moving stuff so that we can start, at some point, in the future. But hey, progress!

With gratefully received assistance from Trevor and Daniel, I’ve been sorting out the wood in the gulley, and by “sorting out” I mean cutting into pieces that can be moved, then moving it as short a distance as I can get away with, coz ffs, wood is heavy when it’s in huge chunks. Yes, this gives me the excuse to wave a huge chainsaw around, and by “wave” I mean swear at whilst trying to start the bastard. Cliff’s big saw has a three foot bar and an 80cc engine, goes through a tank of two-stroke mix in twenty minutes, doesn’t idle, munches through bar oil, is far too loud, and far too smoky, but f’it, it cuts wood and that’s what it’s there for.

 

Yes, the pile of wood is above head-height. It’s seventy-year old macrocarpa and pine. Anyone want it? (Also, it is down a gulley and you can’t currently get in there with even a wheel-barrow.)

Cliff the Builder and Garth have finished off a retaining wall, and built another, so that we’ll have at least some flat land. Then they built a stand so that the huge posts and beams can be stored out of the way. Some of the pieces will weigh 300 kilos when they’re dry, so they’re heavier than that now, thus moving them has involved ropes, pulleys made on site with chainsaws, and Cliff’s Holder tractor, built 1950ish, “so ugly it’s cute”, and now on its third engine, from a Cortina. These are the little bits of wood:

And this week, there’ll be more of the same, with moving the really big bits of wood and getting ready to start hacking into the hill for the foundations.

And that’s about fifteen person-day’s work so far and we’re yet to break ground on the house. Holy crap, this is a lot of work…