Charcoal Making (going to do some metal casting in 2025).

 In a slightly random last post of 2024 I'm going to quickly step through how to make small batches of charcoal! It's pretty well documented online but when I posted over on mastodon I got some questions asking about the process. 

As a random aside, why would you want to make your own charcoal? Well it's quite hard to get decent charcoal these days, most of the BBQ "briquettes" contain a lot of sand and fillers and the lump wood charcoal often commercially available is not to great and potentially not the most sustainably created. So for small batches of charcoal for firing up my small DIY furnace this approach works for me. 

We have some willow in the garden I regularly coppice and this makes excellent charcoal when dried out for a year or so. Begin by finding a tin can, I used a paint can but I've also used large biscuit tins before now, the geometry doesn't matter, just needs to be metal and have a lid that can be sealed on. Whatever your tin cut your wood up into pieces that will pack into the tin. You want to fill the tin as well as possible to reduce the amount of air in the tin and also just to maximise your yield as the volume will shrink as you turn it into charcoal. 

In the lid of your tin you need to make a small hole, or a pair of small holes, don't overthink this, if I had had a large nail I would have made one circa 6mm diameter hole, but I picked up my hand drill and it had a small bit in it and so I drilled 2 smaller holes close together. With your hole in place put the lid on the tin. 

Chuck your tin on a fire and keep the fire burning for a few hours, watching the tin you should see a stream of white gas/smoke coming out from the hole which may or may not catch fire and roar like a quiet jet engine! Once the smoke/gas stops you need to remove your hot tin from the fire and then cover up, or plug the holes to try and stop air from rushing into the tin. I've sometimes stuck the nail I've used to make the hole back in but this time I just used a flat piece of slate to cover it. 

Once cooled, open up your tin and you should be rewarded with nice lumps of charcoal that should be light and brittle. Even with a small paint tin if you repeat this process a few times you can pretty quickly build up a good store of decent quality charcoal. 

Repairing the Mundane, Bike Pedals!

 

If you follow me over on mastodon you might have got wind of one of my current ongoing projects, the restoration of a cheap but excellent recumbent racing bike. I'm collecting video and images of the process so I imagine there'll be a YouTube video and some posts at some point. I do lots of bike tinkering and it's really easy to fall into the trap of just adding better parts rather than restoring parts you have. I'm totally guilty of this but I do try and reuse parts elsewhere if possible. 

The recumbent arrived with a set of flat pedals on it. Painted bright red they were totally serviceable (one needed a little tweak of a nut to take out a tiny bit of play) but the paint was in poor condition. They are absolutely nothing special, they are alloy with cast in pins (the sticky up grippy bits) and as such would have originally been a fairly cheap pair of pedals, not even any branding or name. 

As I kind of progress as a maker type person I start to see more and more how much effort and energy goes into creating these low spec, but not the worst parts in all manner of products and items. If you have ever tried casting metal or machining some kind of curved bearing race cup you'll know too. 

Increasingly I see people repairing and I love it. I also see media starting to promote and push the repair agenda and I love that even more. However I've also noticed that, particularly in the higher end TV/documentary style repair stuff, that increasingly the things that are repaired are either very expensive high quality items (antiques etc) and/or things that people have incredible emotional attachment and investment in. Think Repair Shop and people weeping (quite rightly) over a wartime memento lovingly restored. 

I love it, but it's dangerous, it leads me back to these pedals, they are mundane. We need to repair the mundane too. It's highly likely that I will invest a lot of time into the recumbent bike project, and it might end up warranting technically better pedals than these. I might want different technology, I might want to clip in, but these pedals are serviceable and need to be reused. 

So I stripped them down, I sanded off the remaining paint and oxidisation and then gave them a coat of primer. I then realised that, due to their quick and budget production methods, they still had lots of casting flash from when they were originally made. Not warranting endless effort I ground back the worst bits and re primed them. I then did a poor but functional rattle can respray in a neon yellow. 

As part of the strip down I had to prise out the pedal caps to get to the retaining nuts etc. Of course these plastic items were very snug and to remove them created some damage. A quick measure with the calipers and a little bit of FreeCAD design work and I printed a pair of replacement caps in a pleasing green TPU filament. 

The axles were stripped and then re-greased before reassembly, they aren't pretty, I don't have a shot blasting cabinet or an indoor space for respraying so they are a bit rustic in finish, but, they are once again serviceable and, whilst I say the recumbent might warrant technically better pedals, these will find their way onto a project at some point rather than hitting landfill.

Inkscape Path Effect: Ruler

As a maker I’ve often ended up making rulers and scaled items. If you have access to some kind of laser cutter/CNC router or even just a regular document printer, you can create all manner of measuring and metrology tools! Inkscape can make this process incredibly straightforward with it’s Ruler path effect.

It is a pretty straightforward path effect. In a new project click the Pen tool then hold the control key and left click on the canvas and drag to create a horizontal line. Set the stroke width to something reasonably thin like 0.2mm and set the length of the line to something easily divisible. We opted for 100mm.

With the line selected click “Path – Path Effects” to open the Path Effects dialogue tab on the right hand side. In the path effects drop down menu search for “Ruler” and then select it to open the ruler dialogue. This will apply the ruler effect to our line and you will see some ruler markings appear spread along the line. They probably aren’t spaced correctly so we will edit the ruler dialogue variables to create the effect we want. Let’s aim for a mark every 1mm with a longer major mark every 10 marks so we get a 10cm ruler with mm and cm marked.

First change the “Unit:” drop down selection to mm then set the “Mark distance:” value to 1. You should now see that the ruler markings change to be equally spread at 1mm distances along our original line. Next you can set your “Major length:” and “Minor length:” variable so that you have longer and shorter ruler lines, finally set the “Major steps:” value to 10. You should now see your longer “Major length” lines now appear every 10mm marking every centimetre.

Of course, you aren’t limited to creating rulers that are marked every mm. You can use this versatile path effect to make all manner of scales and rules. In the header image you can see it’s been used to make some “roamer” tools which are used in map reading and navigation. The ruler path effect has been used to make marks where every 4mm represents 100 meters for the 1:25000 scale roamer which is a common hill walkers map scale. Note that the actual ruler marks in the corners of the roamer designs have been edited so they don’t cross over each other. This has been achieved by selecting the entire path effect ruler and clicking “Path – Object to path” this means that then every mark of the ruler can be edited using the “Node Tool” furthering the use of this great path effect!

DIY Opensource Land Navigation Tools.

I’ve been practising my land navigating a little bit recently. With the short days and winter weather it’s useful to practice walking on bearings and other navigation techniques for when visibility suddenly worsens! As part of this I've made some DIY navigation aids. First up is some DIY lasercut perspex roamers. This was partly as I wanted to write an upcoming tutorial on the Inkscape Ruler Path effect (See recent other posts on the offset path effect and the corners path effect) which allows you to create precise graduated ruled scales perfect for all kind of measuring tools.

A “roamer”, or “romer” as some people spell it, is a tool that’s particularly useful when it comes to defining a grid reference on a map. The premise is pretty straight forward you identify the first two numbers of the grid reference directly from the line labels on your map and you then place the zero corner of the roamer on the position you want to create a grid reference for and then read where the roamer scale crosses the map lines to the left of and below the zero point. As an example in the image the grid reference of the Pumping Station marked on the map could be given as SH605641 or even more accurately estimated as SH60556413.

Many compasses have roamers marked on them for common map scales but this project started as my older Silva compass I’ve had for years didn’t have a roamer for 1:40000 scale which is the standard map scale for Harvey maps. After drawing the scales in Inkscape I then added a couple of scaled holes in the roamers which are handy for defining a circular area of a known radius on a map.

I’ve posted the roamer designs as they stand here and they are perfect for laser cutting and engraving, but equally, you could print them on card and they would work just as well!

Secondly I’ve been making some “ranger beads” from Paracord which is an interesting pretty knot with which you can create a sliding bead. A great use for these is they can replace a cinch toggle which is handy but you can also use them to make a great set of pace beads for navigation. There are many tutorials for this knot online like this video on Youtube.

The premise of pace beads is to keep track of the distance travelled on foot and it’s super handy if you suddenly end up walking on a compass bearing with no visibility. I’ve tied 10 ranger beads onto a doubled length of Paracord and then I can slide one bead to the opposite end of the cord when I have travelled 100 meters. To identify the 100 meters you need to somehow mark out 100 meters on a flat surface and then walk the distance counting your paces. It’s common to count 2 steps as a pace so for example you count every time your left foot lands. A good place to find 100 meters marked out is an athletics track on a local sports field, but failing that you can use online maps to drop a pin at a location and then measure out from the pin 100 meters and note exactly where that is. I’m quite tall so my average paces for 100 meters is 58 paces. I loop the pacer beads onto my rucksack strap and then as each 58 paces passes I pull a bead to the bottom, resetting all the beads when I have done this 10 times (Note I could really have just tied 9 beads as the resetting could be the tenth!). 

It’s really accurate, with practice you can even adjust your pace number for when you travel uphill or downhill and I find that I can, checking with the Ordnance Survey map route plotting and other GPS mapping) I can keep to within 50 meters accuracy over 2km, way more than you would travel without checking on a bearing.

Inkscape Path Effect: Offset

The Offset path effect can be used to create multiple effects. One useful application that helps to explore it is to create an offset outer path around a design. An offset outer path is useful potentially for design aesthetics but also useful for applications such as using a print and cut vinyl cutter or a laser cutter where you might want to print/engrave a design and then cut around the design following it’s contours.

As an example lets create a small logo and then create an outer offset path. To begin left click the Ellipse/Arc tool icon and then on the canvas left click and hold, whilst holding the control key, drag to the right to create a small circle. With the circle selected click “Object – Fill and Stroke” to open the fill and stroke dialogue tab on the right hand side. Selecting the “Fill” tab click the “X” icon to turn off the circles fill. Selecting the “Stroke Paint” and then “Stroke Style” tabs set the stroke width and colour so it looks similar to our image.

With the circle selected press control and C and then control and D to copy and paste a copy on top of the original then move the copy to the side. Create one more circle copy so you have 3 identical circles. Position the circles so they are similar to the overlapping design in the image. You can use the Align and Distribute tool tab found under “Object – Align and distribute…” to achieve this, or for this simple example, just align them by hand.

Next press control and A to select all three circles. Next click “Path – Stroke to Path”. This operation converts the circles strokes which currently sit on a central path in each circle so that there is a path at either side of the stroke. To be able to see this you can click “View – Display Mode – Outline” this display mode is useful as it shows paths as outlines with no fill detail visible. You should see each circle now has an inner and an outer path. Finally with the three circles still selected click “Path – Union” and you should see that your design is now one single object and the paths do not cross similar to the image.

Quicktip: Making a union of paths is incredibly useful when using tools like vinyl cutters where we don’t want paths to be cut in overlapping sections of a design.

Moving back into normal display mode by clicking “View – Display Mode – Normal” we can now use the path effect to create a path around the outside of our design. To begin this select our circles logo and then press control C and control D to create a copy. To make it easier to see what is happening let’s move our copy away from the original but leave it selected. Next press “Path – Path Effects” to open the Path effects tab in the right hand panel. From the path effects dropdown click Offset. In the resulting dialogue check that the unit is set to “mm” and enter a value, we added 2 mm. You should see that every path in the selected set of circles is now offset from its original position by 2mm as in the image. Changing back into the “outline” display view if you select the item using the “Node Tool” you will see that the nodes of the path are still in the original position of the circles. We next want to edit the Offset design so to do this we are going to click “Path – Object to Path” the offset design should now be paths rather than an effect and so the nodes will be editable on the actual design as seen in the image below.

Finally we can select the “Node Tool” and then use this to select the nodes of the internal paths and delete them so that we end up with just the external path created by the offset effect.

Moving back to the Normal display mode you will see that probably your new single path object has a fill, use the fill and stroke tools to turn off the fill and set the stroke size and colour to make a thin visible line. Next you can use the Align and Distribute tools to re align the new offset path around your original 3 circles as seen in the header image.

Inkscape Path Effect: Corner

  

 

The Corner path effect can be added to reasonably complex paths to create radius corners. It’s a relatively straightforward path effect to use. As an example lets create a shape with a pair of rectangles and then apply the Corner path effect. 

To begin click the Rectangle Tool icon and then left click and hold on the canvas to start drawing a rectangle, drag the tool across the canvas to create a rectangle. Create a second rectangle and roughly arrange them as seen in the image.

Quicktip: If we just want to add rounded corners to a single rectangle or square we can select the item with the Node Tool and then either drag a circular node or type a radius into the Rx or Ry dialogue boxes.

Next press “Control A” to select both rectangles and then Path – Union to make a single object from the two rectangles as shown in the image.

To add the Corner path effect first select the union shape we just created and then click Path – Path Effects to open the Path Effects tab on the right hand side of the screen. You should see in the tab that the object, named “rect1” is listed below a search input box which has a dropdown menu. Left click on the arrow at the right side of the input box and you should see the available path effects as shown in the image.

Left click to select the Corners path effect and you should see the dialogue with the parameters for the corners path effect in the right hand tab. As a simple example of applying a corner effect let’s set the Units selection to “mm” and then type “5” into the Radius input box.

You should now see that the corner path effect is added to both the internal and external corners of our shape, you can see this in the header image at the top of this post. To remove the corner path effect at any time you can click the dustbin logo in the corners path effects dialogue.

Wuthering Bytes 2024, OSHCamp photo dump!

 

Super minimal post! Just a few images as a memento and flavour of the event.