[Update May 25, 2017: Red Hat’s Tom Callaway rightly - and gently - admonished me for completely overlooking the Red Hat Patent Promise when discussing this issue at the Creative Commons Summit.  It’s a pretty good example of the kind of license this post ends by asking for.]

I think so.  But it requires more than broadly worded promises - especially when it comes to defensive patents.

This post is inspired by Ultimaker’s announcement (both in a blog and forum post) that they were filing their first patent.  Before getting into why I think patents and open source hardware can coexist, I should mention a few things.  

First, nothing in this post is intended as a criticism of Ultimaker.  Open source hardware is relatively new and I don’t think that anyone is in a position to say that they have the one true path for making openness work in hardware.  I’m glad to see Ultimaker be public about their approach and I hope that they continue to be successful (and transparent).  There must be room for experimentation in open source hardware and experimentation means trying new things.

Second, Ultimaker’s relationship to open source hardware has always been and continues to be an interesting one (in a good way!).  They released all of the files for the Ultimaker 2 on github (great!), but used a license that restricted commercial uses of the files (not as great, at least according to the standards of the OSHWA-maintained community definition!).  Were they so inclined, that restriction would prevent them from getting OSHWA certification for the Ultimaker 2.  How much that matters is in the eye of the beholder.  As I said, there are still many trails to openness being blazed and I try not to be religious about which one is right.

Third, and finally, this post is meant to be less a specific analysis of Ultimaker and more of an attempt to use Ultimaker’s announcement as an excuse to think about these things.  

On to the substance….

Is there an inherent conflict between being an open source hardware (oshw)-oriented company and getting patents?  I don’t think so.  There is nothing about having a patent that necessarily conflicts with being open, just as there is nothing about having a copyright that necessarily conflicts with being open.  They are both types of intellectual property rights that can be used to restrict others.  But they don’t have to be used in that way.

Along those lines, I think it would be fairly uncontroversial if an open source hardware company decided to license their patents under a patent license styled after a Creative Commons Attribution license, where anyone could use the patent as long as they provided attribution to the patent holder.  Those are essentially the types of restrictions that CERN and TAPR-style licenses attempt to impose.  If that type of condition is allowable in the copyright world I don’t see why it should not also be allowable in the patent world.

Defensive Patents

The more interesting question might be if an oshw company decided to apply some sort of defensive-oriented license to their patent.

Remember, defensive patent portfolios are intended to be a sort of mutually assured destruction deterrent to third parties who might bring a patent lawsuit against you.  They exist to say “hey, if you sue me for patent infringement I may be able to sue you right back, so let’s chill instead.”  

These sorts of arrangements don’t work with patent trolls who are not actually operating in the business world.  Patent trolls aren’t really doing anything (besides trollin’) so it is unlikely they are infringing on the defensively held patent.  

They can work in a market with bona fide competitors who have shown a willingness to sue new entrants (like, to pick a market totally at random, the desktop 3D printing market) and who might be convinced to hold their fire if they thought the target of their patent infringement lawsuit had some patents of its own to use in a countersuit.

Conceptually, it would seem reasonable to continue to think of oshw companies as open even if they have patents they are keeping for defensive purposes.  While this sort of conditional permission (”here is a license to my patents WHICH I WILL REVOKE IF YOU SUE ME FOR PATENT INFRINGEMENT so let’s all chill”) might possibly conflict with point 10 of the open source hardware definition (license must not be specific to the product), there is room for debate there.  At a minimum I’m skeptical that it violates the principle that point 10 is trying to embody.

Make it Official

That approach comes with at least one big caveat, however.  It does not seem enough to simply say that the patents are being used for defensive purposes.  Instead, the company would have to clearly define what “defensive” means and bind itself to that posture.  

The most logical way to do that would be with a license. That way others could make use of the patent knowing that they have a legally robust set of permissions from the patent owner to do so.  It would be clear what is allowed and what is prohibited, and when a user might run into trouble with the patent owner.

It is here that I think some of these attempts to be defensively open with patents fall down.  I don’t think that a blog post that essentially says “you are cool as long as we think you are cool” quite cuts it (again, I’m not focusing on Ultimaker here - Tesla has a similar approach which also causes some confusion).  It would be much better if a company trying to be open with patents actually bound itself to that promise with something like the defensive patent license.  Unfortunately we aren’t seeing that quite yet.

Right now the good news is that we are seeing companies trying to be more flexible with open promises around their patents.  And on some level the reluctance to formalize rules this early in the game are understandable.  After all, no one quite knows how this stuff will shake out under pressure.

Unfortunately, that reluctance means that we don’t know how good that news really is until those promises are tested in some way or another.  A license would make it easier to evaluate the promises, but that’s not something we have the luxury of seeing in the wild yet. And until we see a real license, I’m wary of giving anyone too much credit for handling their patents well.  That’s because it isn’t easy to evaluate how they are handling their patents at all.

Which means we continue to wait and see.  It would be great if someone like Tesla or Ultimaker decided to step up and propose a real defensive open source hardware patent license.  Right or wrong, that would give everyone a firm benchmark to use in thinking about these things.  

In the absence of that we are stuck in a somewhat theoretical discussion.  At this point the best we can say is that defensively holding patents probably should not categorically disqualify a company from being open source.  It remains to be seen if there is a good way to execute that in real life.

This post originally appeared on the Shapeways blog.

Today, Shapeways, along with Kickstarter, MakerBot, and Meetup, filed comments in the U.S. Copyright Office’s multi-year study into how the copyright safe harbors that allow websites such as ours to function are working. You can read about prior developments in this study here.

The role of the safe harbors are reasonably straightforward. Websites (such as Shapeways) that allow users to post content do not know if the content being posted infringes on copyrights held by others. Without the safe harbor, this would require Shapeways (and Kickstarter and MakerBot and Meetup and Facebook and YouTube and every other site on the internet) to clear every model, comment, video, and other type of upload through the legal department before posting. In other words, without the safe harbor protecting sites from the potential copyright infringement of their users, none of these sites would exist.

Fortunately, the safe harbors allow sites such as Shapeways to assume that content posted by our users does not infringe on copyright until we hear from a rightsholder. At that point we quickly take the content down to initiate the notice-and-takedown process (details on how that process works can be found here).

These safe harbors were established as part of the Digital Millennium Copyright Act (often abbreviated as the DMCA) in 1998. In 2015 the U.S. Copyright Office initiated a study of how well they were working.

In this current round of comments, we made two primary points:

First, we noted that the DMCA copyright process continues to be heavily influenced by trademark law. Including a claim of trademark infringement effectively removes an accusation of infringement from the DMCA process. Among other things, that makes it very hard for users accused of infringement to challenge that accusation. We believe any study on the DMCA copyright process should recognize that element of how the process works in the real world.

Second, we raised concerns about the framing of much of the discussion in the Study. In addition to an earlier round of comments, the Copyright Office held a series of roundtables (which, for reasons known only to the Copyright Office, it refused to record or allow to be recorded either in audio or video but did release transcripts of) to discuss the issues. In both the earlier round and at the roundtables, a great deal of attention was paid to how the largest online platform – Google – interacted with the safe harbors. In our second point we tried to remind the Copyright Office that the vast majority of websites protected by the safe harbor are not dealing with millions of automated takedown requests a year. We therefore suggested that shaping solutions or conclusions with that scenario in mind would overlook how the safe harbors operated in the vast majority of cases.

As far as we know, this will be the last round of comments in this proceeding. At some point it is likely that the Copyright Office will release their report on the safe harbors. When they do, we will make sure to update you on the blog. Let us know in the comments if you have any questions.

This is a version of a post that originally appeared on the Shapeways blog.

Today, we’re rolling out a series of updates to the policies that govern what happens here at Shapeways. There are some smaller, incremental changes discussed towards the bottom of this post, but the biggest update is to our content policy. Specifically, today we are fully rolling out mature content tagging for shop owners and visitors to the Shapeways marketplace.

Shapeways strives to be a home for a diverse range of creative communities.  While we have a strict content policy governing what can and cannot be printed on Shapeways, that policy is designed to allow as broad a range of expression in our community as possible. However, we also recognize that not every community on Shapeways wants to be exposed to every type of content that we allow on Shapeways.

That is why we are announcing the mature content policy. Unlike our other traditional content policy (which is also still in place), the mature content policy does not describe things that are prohibited from Shapeways. Instead, it is a set of guidelines designed to make mature content accessible to communities in search of it and avoidable for communities who seek to avoid it.

Starting today, you can opt into seeing mature content in your profile by clicking here and clicking on the “show mature audience content” box.

Once you have opted in, you will also be able to filter searches specifically for mature content.

If you have not opted into seeing mature content, you will not see it in search results or in product categories. However, you will still see mature content if you visit a shop that is home to mature content or if you follow a direct link to a mature model.

Shop owners should tag their models using the instructions here.

Mature content will be identified based on a “mature” tag added to the model by the designer. Generally speaking, mature content includes the types of NSFW objects that you would expect.   You can learn more about the specific rules by looking at our updated content policy page and scrolling down to “Things That are Allowed on Shapeways if Properly Tagged”.

If you come across a model that has failed to be properly tagged as mature, please flag it using the “report abuse” button at the bottom of every listing in a Shapeways shop. All reports are reviewed by our Trust and Safety team.

Like all of our content-related policies, we recognize that establishing clear rules governing all possible types of expression can be complicated. That’s why we look forward to receiving your feedback on the rules today, as well as going forward. If you have specific concerns, I invite you to raise them in the comments below. If you have questions about a specific model you have designed, I encourage you to send them to the same content-precheck@shapeways.com address that we maintain for other content policy questions. Regardless of your level of interest in mature content, we hope that this new policy will make it easier to find what you’re looking for here on Shapeways.

Other Policy Updates

While mature tagging is the biggest policy update, we are taking this opportunity to update our other policies as well. Below is a quick summary of those changes. Remember that you can always compare the current policy to the archived versions available at the top of each policy page.

Content Policy

In addition to mature tagging, we updated the following:

• Made explicit mention of the repeat infringer policy we have had in place for a number of years
• Clarified that, while most gun grips are allowed under our weapons rules, gun grips that integrate magazine wells qualify as functional parts of a firearm and are therefore prohibited
• Provided a link to the rules governing behavior on the forum
• Replaced a reference to forum “flamers” with a reference to “trolls” due to a sensitivity to the multiple meanings of the term “flamers”

Privacy Statement

We made a small addition to “Information We Collect” and “Information You Make Available” sections in order to clarify that the contents of your user profile may change over time as you add information and we add fields.

Shop Owner Terms and Conditions

In addition to a handful of typos and spacing errors, we updated the following:

• Added an explicit reference to the obligation to comply with the new mature content tagging policy
• Reserved the right to modify shop listings ourselves (for example, to add mature content tags if appropriate) in order to bring them into compliance with the rules
• Clarified that all sales in a shop are governed by the standard Shapeways terms
• Made it explicit that the right you grant to us to use images and prints of models listed in shops is sublicensable to third parties we are relying on to prepare marketing materials for us. For example, we can have a third party print fliers with images of models in a shop instead of having to print the fliers ourselves.

General Terms and Conditions

We made the following changes:

• We clarified that our gift card refund policy could be changed where required by law.
• We updated the warranty language to fully incorporate the terms of the Money Back Guarantee.
• We strengthened our prohibitions against automated traffic dumping.
• We explicitly extended indemnifications to our vendors and shop owners who make customizable models available in their shop.
• We clarified that the general terms cannot be unilaterally amended by an order form.

As noted above, you can always refer to the archived versions of these policies if you want to see the changes specifically. If you have thoughts, concerns, or questions, I encourage you to raise them in the comments below.

A version of this post originally appeared on the Shapeways blog.

Licensing is all about setting rules around what people can and cannot do with the stuff you create. If you make something that is protected by copyright, someone else needs your permission in order to make a copy of it. A license is one legal form that permission can take. In many cases, the license essentially says “I give you permission to make a copy of my work as long as you do X”. X can be “pay me $50”. X can also be “give me attribution.”

Technically, the reason that someone else would need your permission to copy your work is because the work is protected by copyright. If they do not get your permission first, you could (at least in theory) sue them for copyright infringement.

There is a flip side to all of this. Not all work is protected by copyright. For example, functional objects are broadly excluded from copyright protection. That means that someone else can copy the functional item you made without legally needing your permission first. They do not have to worry about a license on your work because it is not legally enforceable. In fact, putting a license on a work that is not actually eligible for copyright protection can create all sorts of unintended problems.

All of which means that if you are creating something that is eligible for copyright protection and want to share it with the world, you should release it with a copyright license. And if you are creating something that is not eligible for copyright protection, you should not release it with a copyright license.

Which is all well and good if the thing you create fits obviously into a copyright/not-copyright category. But what if the thing’s copyright status is a bit more ambiguous? Should you err on the side of releasing it with a license just in case? Or should you err on the side of not using a license so you don’t unintentionally complicate things?  This is a real issue in both the world of 3D printing and open source hardware, where many of the objects in those worlds inhabit an ambiguous copyright status.

This is a harder question than you might expect and this blog post does not try to answer it. Instead, this blog post is designed to try and lay out the costs and benefits of each path. It explains what happens if you over-license by applying licenses where no copyright exists, as well as under-license by not applying a license where a copyright does exist. 

It then ends with a plea for your input. The norms around 3D printing and open source hardware, copyright, and licensing are still being established. Although this is an easy question to ignore, there is a benefit to the community coming together to try and come to consensus about expectations. I am trying to pull together some folks to work on this in 2017, and in order for that to end well we will need your help.

Wait, what?

Admittedly, this problem can be a bit abstract. In order to make the following a bit easier to follow, it will probably be helpful to have a specific product in mind. Ideally, it is an object where the copyright status (is it protected by copyright? Is it not protected by copyright?) is unclear. Since I have used this as an example of an object with an ambiguous copyright status in the past, let’s stick with studiogijs’ birdsnest eggcup.  You could pick any number of 3D printed objects or open source hardware projects as an equally good example.

(Note: none of this should be implied to attribute any sort of position about copyright to studiogijs. I am just using the eggcup as an example because it is a good illustration of the type of object that can trigger this kind of problem. The rest of this blog post also assumes that studiogijs wants to share the eggcup under some sort of sharing-oriented license such as Creative Commons, although the core issues are the same if studiogijs wanted to use a more restrictive license)

Birdsnest eggcup quattro by studiogijs

As you may recall, this eggcup combines functional (read: not eligible for copyright protection) elements that allow it to hold an egg and nonfunctional (read: eligible for copyright protection) elements that mimic the look of a birdsnest. Since there is currently a case being decided by the United States Supreme Court trying to determine if this sort of object that combines functional and nonfunctional elements is protected by copyright, it is probably safe to say that the copyright status of the eggcup is ambiguous.

That means it is not totally clear what happens if someone were to make a copy of the eggcup without studiogijs’ permission. If the eggcup is protected by copyright, making a copy without permission would be copyright infringement. If the eggcup is not protected by copyright, making a copy without permission would be (legally) allowed. In the first case – where copying without permission would be copyright infringement – a license would be really useful. In the second case – where copying without permission is totally legal – a license does not matter very much.

But studiogijs cannot do both. They either have to use a license or not use a license. That choice is not a simple as it might seem.

If it turns out that the cup is not protected by copyright, attaching copyright license to it would be an example of over-licensing. Conversely, if it turns out that the cup is protected by copyright, failing to attach a license would be an example of under-licensing. Since right now the copyright status of the cup is unclear and there isn’t an obvious right answer, designers like studiogijs need to decide if they are going to err on the side of over-licensing or under-licensing.

Here are some of the costs and benefits of either path:

Over-Licensing

Over-licensing would happen if the studiogijs decides to err on the side of the eggcup being protected by copyright and releases it under a copyright license.  If it turns out the the eggcup is protected by copyright, “over-licensing” just becomes “licensing.” The eggcup is protected by copyright and there is a license governing how it can be used.

However, if it turns out that the eggcup is not protected by copyright, “over-licensing” becomes “putting a license where it does not belong.” From a legal standpoint such a license is essentially meaningless: without an underlying copyright, there is no actual punishment for violating the terms of the license. It can be ignored by downstream users. But even this legally meaningless license can send ripples out into the world.

Clear up Ambiguity (Good)

The most obvious impact of over-licensing is to remove ambiguity. While there are plenty of 3D printed things that fit cleanly into a “protected by copyright” and “not protected by copyright” dichotomy, there are also many that fall into a grey area. This grey area can exist because the rules around copyright today are unclear, or because there is a chance that the rules around copyright could evolve in the future.

In either case, adding a copyright license can act as a “just in case” tool. Studiogijs can use the license to assert “this eggcup is probably not protected by copyright, but if it is here’s a license that you can rely on.” That makes it easy for downstream users to confidently make copies of the eggcup under clear rules regardless of the ultimate answer to the “is this protected?” question.

Social Signaling (Good)

This benefit is easy for lawyers to overlook, but it is an important one. Licenses act at a legal level and also (probably more often) at a social level. A well expressed license is an easy way for studiogijs to tell the world “here is how I want you to use my work.” Even if that desire is not supported by the law it can still be quite important to the community. People in a community are motivated by all sorts of impulses not grounded in the formal legal system. If you are a fan of studiogijs you may care how they want people to think about copying the eggcup even if they cannot haul you into court for going against those wishes.

Restriction-Free Licenses Reduce the Downside

A license such as the Creative Commons Zero license would dedicate the eggcup to the public domain. It imposes no restrictions or obligations on the people who would make copies of the eggcup and makes no attempt to control their behavior. In this context, it tells the world “the eggcup is probably not protected by copyright, but if it is I hereby remove its copyright and make it freely available to everyone” while asking for nothing in return. If a studiogijs is relying on a truly restriction-free license in an ambiguous situation, the effect of the over-licensing with this type of restriction-free license is almost all benefit with no cost.

This calculation changes if studiogijs uses a conditional copyright license. Even a very permissive Creative Commons Attribution license could create problems because it places a condition on people who make copies of the eggcup (they are required to give attribution). In this context, such a license tells the world “the eggcup is probably not protected by copyright, but if it is you can use it as long as you give studiogijs credit as the creator.”

If the eggcup really is protected by copyright, such a license is great – all you need to do in order to make a copy is give studiogijs credit. But if the eggcup is not protected by copyright, a person who wants to make a copy might think they are required to credit studiogijs where no legally enforceable requirement exists. In other words, the license attempts to impose obligations on people who want to make copies without the actual ability to do so. That can create confusion and disappointment for everyone involved. All the more so if the relatively benign restriction to give the studiogijs credit is replaced with a more aggressive demand for a royalty payment.

Normalizing Expanded Copyright Protection (Bad)

In addition to possibly imposing obligations that are not legally enforceable, over-using copyright licenses can have a long term effect on how people understand the scope of copyright’s reach. It is not hard to see how “if you are unsure, slap a copyright license on it” can evolve into “the widespread use of copyright licenses in 3D printing means that all 3D printed stuff should be protected by copyright.” That could potentially remove countless objects from the public domain and expand the scope of copyright well beyond its intended bounds. Over-using copyright licenses could evolve into a situation where such licenses are actually legally required.

Under-Licensing

Under-licensing is the flip side. Instead of releasing the eggcup under a “just in case” copyright license, studiogijs could simply choose to not apply a license at all. In doing so studiogijs is gambling that the eggcup is not protected by copyright so the license is unnecessary.

Avoids Normalizing Expanded Copyright Protection (Good)

Not surprisingly, erring on the side of not using a license can have the opposite effect of erring on the side of using it. If in ambiguous situations there is no license, it will set an expectation that no license is necessary. This expectation could prevent the expansion of copyright to cover these edge cases. This could preserve the public domain as it is today.

Complicates Social Signaling

A license is not the only way to signal to people who want to make copies of the eggcup how studiogijs wants them to do so (if at all), but it is a clear and easy one. Without a license, would be copiers who want to take studiogijs’ wishes into account have to rely on other cues in order to determine how studiogijs might want or not want their work to be used.

Can Prevent Further Use (Bad)

The lack of a license, even in ambiguous situations, can create problems. If a person who wants to make a copy of the eggcup is risk-averse (or is having risk aversion pushed on them by their legal department), the lack of a license clearly granting them permission might prevent them from copying the eggcup even if there is no legal barrier to doing so. Additionally, if it turns out that there is some sort of latent copyright in the eggcup, the lack of a license could legally prevent people from copying it even if studiogijs wanted them to do so.

Which is Better?

I’m still not sure. Trying to weigh all of these factors will be part of 2017. If you have thoughts, please let me know. There is not going to be a real “right” answer. Hopefully we can come together to help form some sort of consensus around which of these not-great options is better.

Technically you can use this setup to make any kind of interactive ice luge.  But I used it to make a Trump head ice luge, so that’s what this post is about.  To be clear, when I say “Trump head ice luge”, I really mean, “Trump head spout on an ice luge”.  This isn’t a giant block of ice shaped like a head.

The central principle here is fairly straightforward.  There is a sensor that detects fluid.  When it detects fluid, it triggers 1) a random audio clip, and 2) a change in light color while the clip is playing.  My version played one of 45 random Trump clips and turned the lighting from the default orange to red for the duration of the clip.

Bill of Materials

- Wood and screws for the rack (I used some 2x4s and plywood)

- Lots of cardboard, newspaper, and trash bags (for the ice, more on this below)

- 1 Arduino

- 1 Adafruit Music Maker Shield 

- 1 liquid flow meter

- Tubing that mates with the flow meter (I just took the meter to the hardware store and wandered around the plumbing area until I found something that worked.)

- Funnel

- Clip

- 2 speakers

- Hot glue gun

- 4 NeoPixel Diffused 8mm Through-Hole LEDs

- A 3D printed head

- Wires and a power supply for the arduino.

- Audio clips

Making the Ice

This is going to take longer than you think.  Clear out space in your freezer and make a cardboard box that will fit.  The box will expand a bit with the ice, so make sure there isn’t anything built into the freezer wall (say, posts to hold racks) before sizing the box.  The box here was 2 pieces of cardboard thick and then wrapped in tape.  It was about 7 inches by 14 inches by 27 inches when all ways said and done.

Roll up the newspaper tightly. Use the resulting tubes to build a track into the inside of the box by taping the tube to the wall of the box.  This will create the channel in the ice luge.

Next line the box with heavy duty garbage bags.  Once you have done that, you can start filling up the box with water.  Depending on the size of your block, expect this to take at least a week.  A few tips:

- Chill the water before adding it to the box

- If possible, create a large block (still smaller  than the one you want to make) of ice to seed your full block of ice.  Put it in the box and then fill the box with water until the block floats. The water in the middle freezes last, so if that water is already ice things will go faster.  Plus the floating ice will suggest that you are creating enough outward pressure on the walls to get a nice groove.

- When water freezes, the ice floats to the top.  That means that even if the ice at the top of the box is solid, there is likely still water at the bottom/in the interior.

- Add enough water to push up against the walls of the box.  That will make sure that your channel is deep when you pull it out.

- It will take longer to freeze than you think.  Turn your freezer down as low as possible.

Eventually, if you are lucky and patient, you will have a block of ice.  When it is time to use the ice, just cut away the box and pull off the trash bags.  It is likely that bits of bag will be frozen into the block.  If you are lucky there aren’t that many.

Making the Head

Fortunately I did not have to model the head myself.  Thingiverse user digitalcoleman had already created a low poly Trump head and licensed it under a CC-BY license.  I downloaded it and used tinkercad to create the voids for the tubes, meter, and LEDs.  You can download my version here. 

If I had to do it again, I would have created shallow channels in the bottom connecting the spaces for the LEDs.  That would make it easier to connect them with the wires.

Note that if you print the model at scale it is a really long print.  Fortunately Andy at Open Factory hooked me up and printed it for me. Also note that printing it in a clear material makes the LEDs work much better.

The Code

You can download the code here (it’s final.ino.ino).  As noted in the header, I got a lot of help for it in the adafruit forums.  Hopefully the comments are enough to help you figure out how it works. If you are using everything I used, it should just work.  It should also be easy to find the lines to change the colors if that’s your thing.

You will also need to get your audio clips together.  I had about 45.  Label them as track001.mp3, track002.mp3, and so on and put them on the SD card. (There is no link to this on the musicmaker page, but here’s the tutorial for the shield).  The software will randomly pick a track to play every time. It will also know how many tracks there are, so you don’t need to worry about setting that variable in the code or anything.

Putting it Together

Here’s a wiring diagram (it only shows 2 LEDs but my final had 4)(also, when you are wiring the LEDs I had the flat side facing to the right):

I used a hot glue gun to glue the 4 neopixels into the voids at the bottom and then soldered them together. You can see how having channels between the holes would have helped here.  The fifth and sixth hole are for the mounting screws.

The wiring for the sensor can sneak out the back of the head as well.  Once you have that together, just put the tubes in the hole.  You can then mount it on a block of wood.  I found that the default angle for the head wasn’t quite right in my setup so I mounted the head on an angled block of wood.

Finally, you will probably want to mount the tube and funnel.  I designed a clip to hold it in place.  The file is on the github page.

Once it is all wired up, you just have to mount it onto the rack.  Assuming you did the wiring correctly it should be fairly straightforward.  Here’s what it looks like:

I found that even at a pretty loud volume the speakers weren’t quite loud enough for a party full of people.  About half way through I just plugged it into an amp with speakers.  Fortunately there is a headphone out on the MP3 shield so that was super easy.

Oh, and here’s what it looks likes: