Trem Questions

[Dirge for november]

Hello,

I've just taken up a school assignment on designing a tremolo system. As I'm not to experienced on trems, and don't have acces to all the different models to answer my questions, I thought I'd ask here. Some of these questions might seem a bit lame, but bear with me:

1. What exactly causes the bigsby trem to detune easily?

I reckoned looking at the design that the spring holds quite some more tension then the strings (as opposed to floating systems), which should keep the strings from detuning while using bends. I would think it should even be possible to break a string and remain tune.

2. A really strange question, as it's not logical to know or want to know....But by any chance does anyone here know how much tension is actually on guitar strings? I know it differs with tunings etc. But just to get a general idea. (to see if some spring systems I was thinking about are realistic)

Probably a lot more questions coming up, but just can't think of any specific ones right now.

Thanks in advance.

PS the trem I'm thinking about is going to be top mounted.

[WezV]

look on the back of a pack of strings for tension measurements - or on the string makers website!!

[j. pierce]

As mentioned above, I know one of the string manufacturers has the info on their website - I believe it's D'Addario. I'll have to check later, now I'm curious.

As for Bigsbys, in my experience, any tuning stability problems tend to come from the headstock end - binding at the nut of the guitar, string windings slipping at the posts of the tuners, etc. With strings that have been stretched a few times to break them in, and care taken to avoid things sticking at the nut, and as straight a string path as possible, and careful stringing, I find I can be pretty heavy handed with a Bigsby before I have problems, and all my experience is with vintage style tuners. A roller bridge helps, as well.

The only time I've had a real hard time keeping a Bigsby in tune was when I had one where the bearings on the bar had totally shot. This was a second hand unit, I have no idea how that occurred, but they were in pretty bad shape.

[j. pierce]

http://www.daddario.com/Resources/JDCDAD/i...nsion_chart.pdf

D'addario's tension charts. The first section has all the forumlas needed, the second lists numbers for their various types of strings at traditional scale lengths.

[Mickguard]

A Bigsby will stay reasonably in tune if you're not too heavy handed with it --but they're not meant for heavy hands anyway. And nothing sounds prettier than the Bigsby flutter. Since the saddles don't move, the other strings will stay more reasonably in tune if you break one.

I remember the first time I broke a string on my strat -- I couldn't believe it. I blocked the trem the next day....

One thing about the Bigsby design that might affect its tuning stability is the fact that the spring is only on one side. At least I always had the feeling that was what was going on. And that the spring should have been on the bass side, really. Or at least in the center.

I suggest you check out the Trem King design -- I'll be installing one very soon (another couple of weeks of curing time), so I'll give more of writeup later. But one thing I like about it already is that they really seemed to have looked at every aspect of existing trems to see what they might improve. I can't speak about its tuning stability yet (but I bought it for that--at least, the claims).

[Dirge for november]

Thanks a lot for all your answers!

I'll check out the d'addario site.

I found out about the trem-king yesterday by pure chance. There's a lot of good stuff in there! To bad I didn't think of them first . Now my goal is to have somewhat similar results to the trem king but then on a top mounted tremolo. Impossible I know, but aim for the stars....

As for the location of the spring, that's one of the things I'm definitely looking at. Not only the location, but also the type. (This also to improve the situation with the spring popping out pulling the arm up to far)

Some more questions:

Is the bigsby stable enough to play drop-D?

Is it a problem if a spring works both ways? (As in to heavy to comfortably pull the arm up)

[Mickguard]

As for the location of the spring, that's one of the things I'm definitely looking at. Not only the location, but also the type. (This also to improve the situation with the spring popping out pulling the arm up to far)

!!!!

I've never been able to achieve that...I don't think the Bigsby was made for this....

I also have a headless trem bridge based on the Steinberger. It has a single thick spring, similar to the Bigsby, but it's placed in the center --but beneath the bridge unit. Which means it's close to being a top-mount, but not quite. Haven't built that guitar yet, so I have no idea how good the bridge is at staying in tune. Looks like you can go more extreme on it though.

[Dirge for november]

With changing the spring position, I'm not actually referring to the bigsby, I want to use the "bar" idea of the bigsby, combined with it being top mounted. So I'm also talking about a different spring, for instance a torsion spring (if that's what you call it in English). Could you post a pic of that headless trem bridge? Would be interesting for inspiration I think!

[Dirge for november]

I just realized I might even be able to build a prototype at school (CNC router). Would be cool to try anyway!

[Mickguard]

Could you post a pic of that headless trem bridge? Would be interesting for inspiration I think!

PM me with your email address, I'll send you a few photos.

[Dirge for november]

It's been quite a while since I worked on this project. I finished up a prototypical design and used it as an extra assignment in my internship report. Now I'm getting the itches again and would like to make it for real with the CNC router at school. When actually wanting to build the tremolo some more questions popped up. I hope I can find some of the answers here. Some of these questions I could find the answer to by myself if not for one problem. I'm stuck in bed for the time being.

As I don't have acces to a bigsby... And can't go out to check one out:

1. Could someone with a bigsby determine the diameter of the bar around which the strings are situated? and also the one that keeps the strings down.

2. Could someone please take a detail picture of the bearings?

3. A TOM style bridge is angled with the bottom end slightly more towards the neck, doesn't this cause a slight angle of the strings on the string saddles, thus causing friction? It must be a negligable amount, but I want to improve as much as possible...

I hope someone can find the time for this... It would be really cool!

[j. pierce]

As I don't have acces to a bigsby... And can't go out to check one out:

1. Could someone with a bigsby determine the diameter of the bar around which the strings are situated? and also the one that keeps the strings down.

These are from a Bigsby B-500... these are the import "licensed" models, so everything seems to be metric, I think the original models are standard? The measurements seem to line up more with metric on the unit I have. The measurements are all a little off, probably from the thickness of the plating on the plated parts, but they line up more with millimeters than inches as far as being numbers that make sense.

The bar with the string retainers is 10mm in diameter. The retainer bar is 10.5mm.

2. Could someone please take a detail picture of the bearings?

When I can find some camera batteries, I'll do what I can - looks like I need to take the unit apart a bit to do so.

3. A TOM style bridge is angled with the bottom end slightly more towards the neck, doesn't this cause a slight angle of the strings on the string saddles, thus causing friction? It must be a negligable amount, but I want to improve as much as possible...

I'm not sure what exactly you mean here - Are you talking about the bridge being perpendicular to the string path rather than the back of the guitar? The stewmac plans for an LP that I have show the bridge being perpendicular with the plane formed by the back of the guitar, but I may be misunderstanding what your saying.

I've not found problems with that area because I use roller saddled bridges on the guitar I had a bigsby on.

I'll get pictures up when I get a chance.

-j

[j. pierce]

Eh, here's the best I can do right now - unless I get my hands on a split ring removing tool (I swear I had one!) I can't get better shots of the bearings. They definitely feel like there's ball bearings in there, but perhaps they're like bicycle bearings, with just a race and balls, or a half cup, not sealed units like on a router bit. Can't really tell what's going on until I can remove the nylon. I'll see if I can't get the tool I need from my father or one of the guys at work.

Here's the photos:

From the bass side

from the treble side

from the inside of the bass side

from the treble side, with the arm removed (the arm retaining grub screw definitely confirmed this unit is in metric.

Sorry they aren't great photos.

Gets me thinking about a project I wanted to tackle - reworking a jaguar style trem, with bearings underneath, rather than just two large plates bearing against each other.

I feel like part of the instability of the bigbsy trem is from the placement of the spring - it just feels kind of lopsided, especially with certain strings. But I'm really just making a gut feeling judgement on how the thing feels in use, I can't say.

FWIW - if you want a real unit to look at, I might be willing to let this one go, as it's obviously not being used right now.

[SwedishLuthier]

Dirge, what’s the main idea behind your tremolo if I might ask. I'm curious as I myself did a school project (some 20 odd years ago, together with a class mate) with a Bigsby style tremolo that was designed to lower/rise the pitch evenly on all strings. Sounding more or less like a steel player moving the steel along the neck. We did the most critical parts on a CNC lathe but newer got around making a complete unit. We also did a bunch of math on sting tension vs note pitch, finding out that it has already been covered by Pythagoras some 2-3000 years ago…

If you need some more measurements or pictures I might also be able to lend a helping hand. I have some Bigsbys here and I have made a CAD draft of one from at least two angles. I’m a bit curious were this is going and would love to see the finished result.

[Dirge for november]

Hey! Thanks for the very helpfull replies! The reason I needed those measurements is to be able to continue my design. The side hight is based on the diameter of the bars and of course so is the amount of pitch change. Mm's are fine, even better as I'm dutch and dutch people don't like inches . The pictures are also very helpfull, as I had no idea how it looked. About your bigsby, how much do you ask for it?

@SL

Your project sounds very interesting and complicated! I think this is a bit more basic. My idea is basically a bigsby and tunomatic in one without the problems of the existing bigsby. Difficult to achieve perhaps, but it would be fun if I pulled it of. The looks will be quite different from the bigsby, and so will the spring system. I'm also interested in you CAD drawing, would you be willing to share it?

I'll post as soon as I have an update..

Cheers

[SwedishLuthier]

Yupp, our project was too complicated as we never were able to make something that worked in real life. But the project didn't include making a a finished product so we nevertheless got good grades.

The CAD isn't 100% accureate but pretty close. PM me your email adress and I'll send it to you.

[LarsXI]

I was thinking about modifying a Bigsby a couple months ago. I thought about using a torsion spring or two. It would be interesting to try one on each side of the bar. Also, I thought about actually increasing the diameter of the bar thinking that this would allow more movement and thus more pitch range. Finally, I had vague thoughts about changing the arm/lever itself into one that used a simple gear ratio for better movement. Unfortunately, I didn't actually try any of this. But hey, food for thought.

[SwedishLuthier]

E-mail with drawings (B5 and B7) sent.

If anyone else would like them too, just send me a PM with your E-mail adress.

[j. pierce]

Dirge - forgot about this thread entirely - just got my hands on a split ring removal tool, so I can take apart the Bigsby more and take pictures and measurements - but it sounds like Swedish Luthier's got you covered with his drawings?

S.L. - what file format are your cad drawings? Are these from the top? Could be useful to folks (like me!) who plan their instruments in CAD or vector art programs - should see about getting them added to members download area!

[SwedishLuthier]

J. I use TurboCAD and can save in a numerous different type of formats, DWG, DFX, GIF, JPG, PDF and so on. I think it is almost 20 different formats availible. Is there any special format you need? It is a quick job to resave the drawing in a different format. The drawings are from the top and from one side, bottom side. I'll be happy to help if you need the drawings.

[j. pierce]

I do my layout in Inkscape (open source version of Illustrator) so SVG is the keenest for me. PDF works great as well. Illustrator files work all right, particularly 9.0 and later. .DXF is sort of workable.

Unfortunately, I don't have much of a way of getting DWG files to work without converting to bitmap in the process, cleaning up the results and then making it into vector again, which is usually fine for layout, but just means more work. I need to go searching for a decently priced tool for converting DWG to other vector formats on a Mac.

Anyway, didn't mean to thread jack - but I would love a copy of those files, (PDF is probably sounds easiest) if you get a chance. No hurry.

[Dirge for november]

@J.pierce,

Yeah I've got all the info I need for now, thanks for all the work! I've got a proto design in solidworks now. When a buddy of mine comes back from studies abroad we'll start calculating the springs. Something I'm not looking forward to at all. After this we'll adjust the design and see if we can pop it into the CNC.