Obligatory legal note: Design of this Device is copyright Christine Schoedel 2006-2009. The design and construction instructions below are released under v1.0 of the TAPR Noncommercial Hardware License. Full text of the license is at the end of this post.
The materials used to make the Device are:
Aluminum bar, 1"x1/8" This is sold at hardware stores, usually in 4' lengths.
Hose clamp, 1 1/4" size.
Steel wire, 28 gauge.
Dremel multi-tool with cutting blade and 3/16" drill bit.
Electric screwdriver (optional).
Sanding block, or sanding bit for Dremel.
All of the supplies are fairly inexpensive. Enough supplies to make three of these, purchased at Home Depot, came to just over $25. That included two types of epoxy, and a spool of wire that ended up unused because it was too thick to bend easily.
Most of the epoxy was not used, as was most of the wire. A single spool of wire and package of epoxy would be enough to make many Devices.
Cut a 1' segment from the aluminum bar. First, measure and mark the aluminum bar where it will be cut.
Secure the aluminum bar, then cut with the appropriate cutting blade/disk on the Dremel.
Sand off the cut end of the aluminum with the sanding block or Dremel bit. Be sure to get this part very smooth, as it will go against the forearm of the person using it.
Next, secure the 1' piece of aluminum, and drill 2 holes through the end that was not cut. These holes should be around 1/3" to 1/2" from the end.
Next, position the hose clamp between the holes and the end of the bar. The loop of the clamp should stick out past the end of the bar, so that it can be adjusted easily. Cut a 3' long piece of steel wire from the spool. Then, wrap the steel wire several times through each of the holes and around the body of the hose clamp, to hold it in place. Use the needlenose pliers to tighten the wire-wrap and tuck in the ends.
The next step can vary slightly, depending on what type of epoxy is used. If a more liquid epoxy is used, squeeze some onto a disposable plate and mix it up. Apply it to the aluminum bar and wire-wrap. Be careful to not get any epoxy inside the hose clamp, but do work it into the wire wrap and be sure it fills the holes in the aluminum bar.
If a paste-type epoxy is used, knead it as directed on the package instructions, and then push and smooth it into place on the Device as above. Be sure to completely fill the holes in the aluminum bar, and to cover the wire-wrap.
Put the Device in a safe place and leave it undisturbed for 24 hours, or until the time the epoxy package says it will take to fully cure. After that time, any rough edges of aluminum should be sanded smooth.
The Device is now ready to be used! The hose clamp size specified above works quite well with dry-erase markers and wide gel pens. For thinner implements such as crochet hooks, simply pad or wrap the handle with tape - electrical tape is a bit more stable in the Device than duct tape.
The Device is licensed under the TAPR Noncommercial Hardware License v1.0.
Full license text:
The TAPR Noncommercial Hardware License
Version 1.0 (May 25, 2007)
Copyright 2007 TAPR â€“ http://www.tapr.org/NCL
Open Hardware is a thing - a physical artifact, either electrical or
mechanical - whose design information is available to, and usable by,
the public in a way that allows anyone to make, modify, distribute, and
use that thing. In this preface, design information is called
"documentation" and things created from it are called "products."
The TAPR Noncommercial Hardware License ("NCL") agreement provides a
legal framework for Open Hardware projects. It may be used for any kind
of product, be it a hammer or a computer motherboard, and is TAPR's
contribution to the community; anyone may use the NCL for their Open
Hardware project. You are free to copy and use this document provided
only that you do not change it.
Like the GNU General Public License, the NCL is designed to guarantee
your freedom to share and to create. It forbids anyone who receives
rights under the NCL to deny any other licensee those same rights to
copy, modify, and distribute documentation, and to make, use and
distribute products based on that documentation.
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or use a product based on that documentation. For better or worse, patents
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of course cannot prevent a third party from enforcing their patent rights,
those who benefit from an OHL design may not bring lawsuits claiming that
design infringes their patents or other intellectual property.
The NCL addresses unique issues involved in the creation of tangible,
physical things, but does not cover software, firmware, or code loaded
into programmable devices. A copyright-oriented license such as the GPL
better suits these creations.
The NCL is identical to its cousin, the TAPR Open Hardware License,
apart from its added requirement that products can be made only for
How can you use the NCL, or a design based upon it? While the terms and
conditions below take precedence over this preamble, here is a summary:
* You may modify the documentation and make products based upon it,
provided you do not make more than ten units in any twelve month period.
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