So, a small metal clip is a bit of an achilles heel for the Eigenharp Tau. It connects the instrument to a strap that goes around the neck. These clips are quite hard to come by these days and was originally sold as an optional extra, so I think several of us in here would like a DIY variant.
The outer rounded part with a hole in the middle will be rubbing against the body when playing. The inner “handle” is a bendable metal plate that releases the clip when bent because the two bronze blocks gets pulled back.
The slot on the Tau that this goes into is attached by screws. So in theory I guess the whole slot could be removed and replaces if there is some existing product that could work. The Tau weighs 2.1kg, so there will be some strain on the part that sticks out at a 90 degee angle and attaches to the inner strap.
Any ideas how to go about this? I think I might have access to a CNC machine in my home town. Perhaps this could be a combination of wood and a metal plate? Wood and 3D-printing? I’d gladly spend some cash to get parts made somewhere if such a service exists…
Part of the clip protrudes aprox. 3cm from the instrument. It is not obvious to me why or if I would even notice if it didn’t. Perhaps to make sure the player’s body don’t rub against the 3.5mm headphone socket and/or bottom of touch strip (seen in the picture below)?
Physically install a guitar strap button/peg where the slot is, and use a guitar strap attached to it. Use a string to attach the other end of the guitar strap to another part of the Tau so that it functions properly.
This idea focuses on accessibility, since guitar straps and their buttons/pegs are widely available, and is heavily inspired by the LinnStrument’s compatibility with guitar straps.
you could just attach with one peg…
the tau (and alpha) are designed to have a good balance/centre of gravity from this single point.
which is why the official straps only have one connection point.
this single point, allows players to move freely between a more vertical or horizontal position, through rotation - which can be useful when using the breath pipe (vs using without).
what’s actually interesting is the bracket over the clip…
at first, I thought it was just so you don’t have the attachment digging into you.
but on reflection I think it is to push the tau a little away from your body, into a more natural position to hold… since the tau is very slim.
… this would be consistent with the Alpha, where the official harness also keeps the instrument position a bit in front of your body, which is very comfortable for your arms/hands when playing.
Eigenlabs spent quite a lot of time thinking about the ergonomics , as the instruments are very much designed to be played standing up, and walking around the stage as part of the ‘performance’
… some quite interesting design stories around about this.
(John had very strong opinions in this area … so quite focused ;))
I was wondering if this might be something that Eigenlabs might be willing to reveal, as it seems far from their core IP. Have you asked them if they can provide a description of the part?
I do not think we can rely on Eigenlabs responding to our inquiries at this point. I have already attempted to send emails to them and John multiple times over the last few months, but either no one responds or the email cannot be delivered due to time out of their mail server.
I like the idea of a super simple “guitar strap adapter”. Something like this, perhaps (both strap ends should go on the same peg, as TheTechnoBear mentioned).
Plusses: Always attached, easy design, just connect strap when needed
Possible negatives: No spacing between body and instrument, danger of the straps coming off the peg?
I measured the actual strap against a normal guitar strap I had lying around, and the guitar strap could be adjusted to be just as short and was looking almost identical to the official Tau one, so that isn’t a problem, at least. Replicating the “inner strap” part should be very straight forward, too, so perhaps the inner strap could end with one of these so that it could easily be attached and removed, but still secure? The adapter part would need a ring or hole of some sort so it can be easily attached, obviously.
EDIT: I too suspect some space between instrument and body is needed/preferable, but I wouldn’t want that always sticking out (the Tau wouldn’t fit in the flight case, etc.)
Do it. As for a secure strap, I used the D’Addario Auto Lock Guitar Strap in Skater Black for my LinnStrument during the earliest days. Consider using this strap or a different colour in your design and see if you can make your adapter more suited for it.
yeah, this clip would be better, more secure (similar is used on the pico) and has the ability turn etc.
good point… yeah, this bracket is part of the connector, so is removed on the official connectors.
as you say, doesn’t need (or want) to be part of the adapter screwed into the tau.
perhaps this could connect to the strap (i.e. strap threads thru it)? also could be a relative simple piece…as its not weight bearing…
(and optional, since it may not be needed)
If the unit consisted of two pieces, one for the guitar adapter, and the other for the bracket, that would solve both problems, allowing the unit to be modular.
I never had a strap for my Tau and there’s no chance to get one anymore it seems; I’d also be interested in something that was compatible with a guitar strap.
Well maybe inquiring Eiganlabs by mail or phone about Eigenharp straps is a potential solution. It is too much of a stretch for me to justify doing so on behalf of the Poly Expression community, so those interested in seeing this through to the end will need to consider these remaining options themselves.
According to John, the factory that manufactured the strap clips (and the cello spike) messed up and lost the tooling they used (and then blamed EigenLabs for it). So that is why another production run never happened and they sold out.
I think I know what the protruding bracket is for, btw. Since it is to one side of the Tau, it tilts it slightly so that it is possible to see the keys when looking down.
Welp, I bit the bullet and tried my hand at creating an adapter. I removed the bracket from the Tau body and measured all the dimensions as best I could. @Kai or others, I need a little help with getting a couple precise measurements (in mm) on the official adapter since I don’t have one:
I have a rough first version of the model (without all the fillets etc) which I will print at a friend’s house soon. The idea is to do it in plastic and see how sturdy it is. The version shown below uses elastic deformation of a plastic tab to hold two the “teeth” in place. I’m not sure how trustworthy that will turn out to be, so I am going to make another version which is a 2-piece assembly where the teeth snap into place.
This version has a bunch of different size holes to test out screwing in different strap buttons. I don’t have much CAD experience, we’ll see how it goes!
the issue is… if you reinforce here, you wont be able to move to ‘snap into place’ as you mention.
also the strap attachment, I can see you modified (as required) to fix directly to backplane , with the long tab of the original (which for sure would break in plastic)…
but I wonder if it might be better to do in parallel to backplane.
this would mean the back plane could be flush to the tau, and which would remove a bit of pressure not the point I indicate above.
I fully appreciate the desire for it to be removable… as some play sitting down (wo/ strap), and standing up (w/ strap) , but perhaps first attempt will be easier for it to be fixed by screws directly?
OR… how about we forget guitar strap… and instead go for a saxophone strap?
saxophone straps have the advantage they have a clasp…
this we could have a simple ring on the bracket to allow for removal, but the bracket could be completely rigid.
what I like about this, is the clasp also is able to pivot a bit, which I think could add a bit of comfort to it.
Looking great! If your friend has a suitable printer with an enclosure, best ask to print this in nylon. Otherwise PETG could work (PLA - the “standard” 3d printer material is too brittle for functional parts).
