Hunting the Harp Plug-Loop

I made this set of photos to show my friend Arthur how the harp-loop functions with the harp when he offered to help connect me to a potential manufacturer.  The easiest way to share them was to put them on my blog.  So here they are.

This is not an official blog-post – but if you’re here, feel free to look at it.

This is what the “unbent” harp plug-loop looks like:

This is what the ‘bent” one looks like.  They both work equally well.

This is what the harness clip looks like attaching to the unbent plug-loop:

This is what the harness looks like attached to the bent plug-loop.   Both bent and unbent work fine.

These are my unschooled attempts to draw what a useful plug-loop might look like.

This is what the plug-loop actually looks like, which is fine except it makes the harp too long to fit in some cases, which would mean you’d have to unscrew it, which you DON’T want to do, because if you lose the plug, the harp is unwearable.

To see the harness in action, go to http://bit.ly/vai-dhc

Arthur’s questions & my answers:

1. Can you remind me how many pieces you ultimately would like?  Quantity always has some bearing on how something is produced.Depending on cost, my preference is to start with 100. If that’s unrealistic in terms of their cost, I’m open to suggestion. That would be enough for me to test out whether the project works. If the project works (If people buy my harnesses) then subsequent orders might change.  If they’re like CDs, I’m assuming that the first unit is the one that costs alot and the cost of units 2-through-gazillion are pretty minimal. Is that the same with things like this?
2. How heavy is the harp (approx)? 11lbs (5 K)
3. Is there any reason why the loop needs to be separated from the heavier threaded plug that screws into the harp?  Your piece was made by combining two pieces- a plug with external and internal threads and a screw-eye threaded into it.  The simplest and perhaps stronger way is to make it as one piece- a very different production method but I’m sure pretty trivial for these folks.There’s no reason the loop needs to ever be removed from the plug. I think the engineer who made this one was modifying their harness-plug to make one for me that works with my harness.
4. The loop on your harp is bent.  Is this intentional or is it a modification that you made?  If it was not intentional it is a sign that the piece is not strong enough and this should be addressed in the new part- especially if you are going to sell them!  🙂That’s unintentional, but the loop works either way, and there are advantages to it being bent (it fits in the harp case more easily), and disadvantages (It’s slightly harder to connect the harness to it). In a ‘perfect world’ (Wow, I just realized I can redesign this slightly to make it work even better), the loop would be more oblong because that would avoid making the harp too long for a standard case, and still make it fairly easy to connect the harness to it (I’ll draw a picture of what I mean and attach it)
5. I did not see the clip that attaches to the loop.  What is the size and nature of that?  Perhaps you can send a little photo? (I’ll attach a photo.)

6. How important is the orientation of the loop at the bottom of the harp?  I’m imagining that when it is screwed in and tight it needs to be in a particular direction?  (plane of loop parallel or perpendicular with plane of harp?)  Perhaps not?It’s probably best when it’s oriented a certain way (horizontal to the player) BUT I’m not sure that’s completely controllable (because of how the harps are made – each housing for the plug may be randomly inserted), and I’ve never had the luxury of it being oriented the way I want, so I often untighten it slightly to make the loop orient in the best way for me.
7. Can you think of any other issue or design requirement or need that would be important to consider?Yes! The fact (which I hadn’t thought of ‘til I got your questions) that the loop adds length to the instrument and affects how it fits in the case. The last thing I want to do is to have to remove the plug for any reason, since the harp is unplayable without it (and it’s a small, easily losable thing), so if I’m building the ‘perfect’ loop, I’d build it differently (I’ll make a drawing).
8. Do all small harps have such a threaded insert at the bottom?  If it is a standard thing then perhaps the threads are standard?  (I think you said something like that but we were pretty rushed before leaving.)No, other harps don’t have a threaded insert. This insert is specific to this instrument, the ‘DHC’ electric harp.  The earlier prototypes of this instrument were wood, and I simply drilled a hole for the loop. The threads do not seem to be standard in the U.S. I spent hours in a hardware store trying to find any screw with this particular threading, and couldn’t.  The threads may be standard in France, but I don’t know.  I can write to Fred, the French engineer to ask.  He has offered to make me some, but I don’t feel I can ask for the quantity I need – and if the project is successful, I need to make sure I can get quantities quickly.
9. Timeframe?I’ve been wanting to move forward on this for years, with this problem as the big fly-in-the-ointment. So it’s not urgent. Once this problem is solved I can move forward to finding someone to manufacture the harness itself.
10. Maximum or desired cost estimate if you have one.
    I’d love to spend no more than $5 a plug (is that absurd? I’ve no idea). If I could get it down to $2.50 or less that would be even better. I’ve no idea if that’s ridiculously high, low or totally realistic.