• 2015
  • Sep
  • 9

MINI KOSSEL - building a better carriage

Since xmas I am an owner of the 2014 Makergeek Mini Kossel Kit (http://www.makergeeks.com/mikofudiypae.html).

The kit is great - it came almost complete with solid parts for the frame, extrusions, enough nuts and bolts as well as linear rails, and a glass print surface. Belts, RAMPS, Arduino Mega, Power Supply, etc.

But the kit came incomplete, mine was missing a fan and a themistor. Living in the bay area pieces from Jameco where easier to order than trying to get the missing parts from Joshua at Makergeeks (Who was very helpful with advise during the assembly phase).

The worst part however where the 3D printed parts for the printer.
Especially the carriages that attach to the linear rails were rather badly produced. The parts were printed in a hurry, probably too hot and the infill was insufficient. This became clear during assembly. Due to the construction of the kossel the carriage is constantly under pressure.

carriageoriginalsmall.png

So as one of my first projects after printing a bed holder from thingiverse I started working on a replacement carriage and looked at a number of existing options before designing my own part. The design goals were easily defined:

  • Mount on existing linear rail
  • Provide maximal freedom for the traxx mounted carbon arms (I created my own since the makergeek arms did come apart during assembly)
  • Design for maximal stability of the carriage - especially for stable mounting of the belt holder
  • Ensure lasting pressure does not deform the belt holder
  • Design the carriage to not require zip-ties to fix the belt to the carriage
  • Help easy calibration of the printer by providing a calibration screw

The following part was the result of my openscad work:

carriagecustomsmall.png

As you can see the piece holds the belt in place by looping it back on itself. Therefore making the additional zip-tie optional. The opening for 4 screws in the back M3×10mm (from mrmetric) provide additional stability to the carriage.

The CC0 openscad file is attached here - and available on thingiverse as STL and openscad file.

I printed mine in 0.2mm layer height PLA on the kossel with support created with kisslicer, with 75% infill (I believe they would have been sufficiently stable at 50%). They have been used for over 2 months now.

Please let me know about any further improvement ideas you might have. I am planning to create a new effector next, before looking at magnet or all ball/spring mount options.

  • 2015
  • Aug
  • 8

3D Printing Toolbox

* Calipers

  • 2014
  • Dec
  • 1

JMT - John Muir Trail 2014 - Gear Review - Elizabeth Wenk - the essential guide to hiking America’s most famous trail

The essential guide to hiking America’s most famous trail

When hiking the John Muir Trail this year - were looking for a good guidebook and after a lot of reading we settled for

JOHN MUIR TRAIL
The essential guide to hiking America’s most famous trail
by Elizabeth Wenk and Kathy Morey
published by WILDERNESS PRESS

The book

The book consists of 4 sections

  • General Logistics - A section outlining trail logistics
  • Trail description north to south - about 80 pages
  • Trail description south to north - about 80 pages
  • The Appendix -probably the most useful part of the book

So most people will probably not take the full book with them on the hike, since only about 100 pages are useful on the trail.

General Logistics

This section outlines some very basic planning instructions on direction, timing, permits, and transportation. The section also outlines basic trail information such as food storage, campfires, and water.

So if this is not your first sierra hike you will not be getting a lot of meaningful information on this.

The hiking guide

The hiking guide makes up the core of the book - 80 pages per directions. While you would be expecting this to be the most useful part of the book, I got much more information out of the appendix than out of this section.

Elizabeth Wenk wrote a her Ph.D. thesis on the relationship between rocks and plants, and she is using this information extensively in this section, you will learn how the plants growing in any specific area of the hike are related to the specific rocks you are climbing over.
Unfortunately Elisabeth is going into excruciating detail about the plants living along the trail, while she is only giving a high level overview of animals and neglects to mention them when you pass through their habitat.

So what out for the yellow legged frog in the high altitude lakes (as you climb towards Muir Pass) and make sure to notice their gigantic tadpoles. Despite their large numbers you will not find them mentioned in the book.

The book does however give useful information on campsites and river crossings. The fauna sections I suggested to skim or skip entirely.

Appendix

The appendix is actually the best part of the book. It details the location of campsites using coordinate, so you can find them onthe maps, and provides information on the resupply spots - so mostly the Muir Trail Ranch, and Reds Meadow.

Both excellent spots to resupply.

Conclusion

The book is somewhat useful, and has up-to-date information in it. Elisabeth seems to be hiking the trail at least once a year. The flora (and there is little of it as you get into the higher elevations) is much over-emphasized and fauna barely mentioned.

Nevertheless - the book makes for a good read, at night in you sleeping bag, getting ready for the next day.
We did in fact scan its pages, so we could read it on an amazon Kindle - which by itself was lighter than the book.

You can find more on how to turn a book into an ebook for your personal use in a future post.

Update

The latest edition of book is now also available for kindle (here - so you will not need to scan it yourself:

  • 2014
  • Oct
  • 13

JMT - John Muir Trail 2014 - Hiking Hacks - Building a tripod

The Problem

When hiking the John Muir Trail this year - we camped on the Bighorn Plateau - which is a beautiful spot, though camping there is very exposed. So there is not a single tree to be seen.

Now - when at camp we usually hang our water bladder from a tree, and also put up a cloth line but that needs at least one strong fix point.

The Solution

Without a tree we decided to build a tripod.
This is the bill of material:

  • 3x Hiking poles
  • 1x MSR Ultralight Utility Cord Kit

We used a simple tripod lashing:

Start with putting the 3 hiking poles next to each other… leave about 1.5 times the handle width in space between them, and start with a clove hitch.
Go above and below the poles 3 to 5 times.
Finish it up with an additional clove hitch.
Turn the center pole a couple of times until you feel the contraption turn stable

For added stability you can run the line around the poles after standing the tripod up.

To stand the tripod simply put one of the poles at the end between the other two and finally hang the water bladder from the tripod. Very simple, effective, and efficient. It also worked perfectly as the counterpoint for the cloth line (simply by attaching the loose end to the tent).

This is what it looks like in the wild:

tripod.jpg

  • 2014
  • Oct
  • 6

JMT - John Muir Trail 2014 - Gear Review - Shelter/Tent

For our hike of the John Muir Trail this summer we were carrying a full tent for a shelter.

h2. Before the Hike

After quite some research the tent we picked was a new MSR release.
So this is the pack list we ended up:

On the trail

While on the trail we pitched the tent on granite, sandy ground, forrest grounds, and fairly rocky ground and the the tent got wet and froze. When wet the tent was drying quickly and handled easily.
It is somewhat hard to pitch for single person, since the “double Y” single tent pole while being super handy is somewhat unwieldy for a single person to handle.

But - we also realized that if the Needle stakes hit a root they are extremely hard to extract. On one occasion we did spend about 45 minutes until we got it back - eventually using the trowel we did manage to get our stake back. But on the flip side - the stakes did hold every single day.

The tent comes with an over-sized bag - which opens along the long side - which makes it super easy to put the tent back into its bag. Which makes you wonder why you spent the last decades pushing tightly rolled tent rolls into tiny bags.

The tent has 2 doors, to the side, which makes it way more comfortable than our previous front entry only tadpole tent. It also comes with two vestibules which allowed us to store most our gear during a nightly downpour.

Conclusion

The tent worked out perfectly.
I would wish for the footprint to extend beyond the actual size of the tent floor and allow to keep at least the cloths and some other gear of the ground. Interestingly in the future I will try to hang some things inside the vestibule from the spreader pole.