Measurements for fingers?

[Jeffrey]

Hi everyone,
I'm getting ready to attempt my first set of changer fingers, and was hoping someone could help me out with the measurements? I'm wanting to make an all-pull changer, probably the type with one rivet, that hangs from the changer axle, along side the finger. (hope I described that right ). But would also be interested in the measurements for the two rivet kind(?). I've looked at plenty of pictures but, without a reference, can't get any accurate figures. Thanks, in advance, for all the help!

Jeffrey

[Bent]

Jeffrey, You'll have to sit down and draw a full size profile of a steel body(as if you are looking at the steel thru the front apron at changer end) The thickness of your steel body determines the size of the changer. You need to make sure that the top raise hole in the finger lines up with the top rod hole in the bell crank. There are no hard and fast rules, we all do it a bit different so therefor it is hard to make a drawing and tell you that's how it's supposed to be. Read posts about string height from body; neck thickness, etc
Get yourself a few sheets of 2X2' white Bristol board and go nuts! As you get stumped, fire questions at us, or reference old posts and you'll be off and running!

[Storm Rosson]

Remember that finger length and all associated parts ,is the primary ratio determining factor, I'll post the dimension of a Sho-Bud +3, -2 , finger when I get a chance today. What Bent said is what you want to aim for ie: a straight as possible lineup from changer finger hole, to corresponding bellcrank hole......Stormy

[richard37066]

Bent and Stormy: -

Good points all around for getting him off of the ground. However, Bent, I would slightly disagree with one point:

The thickness of your steel body determines the size of the changer.

I should think that it would be the other way around. If one chooses to use a rudimentary changer with minimal raises and lowers then the body can be made shallower. On the other hand, if a full-blown changer with 3 or 4 raises and lowers is desired then the body would have to be much fuller such that the mechanicals are not hanging out of the bottom.

If the changer design is first settled upon, then the location of axle holes, string height, neck thickness, top thickness, crossrods, bellcranks, pullrods, etc can then be plotted. The body can then be designed around the mechanicals instead of the mechanicals being shoe-horned into a given volume. This affords the designer the lattitude to optimally place all of the components without a nagging concern regarding physical limitations. The downside to this is the possibility of relaxing such things as the spacing of the pullrod holes in the changer fingers. Relax too much and the cabinet then approaches being a coffin with splindly legs.

I would advocate something which has been stated many times: - View accepted practice of the many builders in order to remain on firm ground.

And Bent - I fully agree that a full-size and accurate drawing is the only way to fly - but with the desired changer being the first thing put to paper. As to the Bristol board - I, personally prefer to use Vellum paper even though it's pricey. Attempting to put everything on one sheet of paper can get messy and confusing. Vellum affords one the opportunity to overlay one drawing on another - it's semi-transparent - in order to determine if everything fits as envisioned.

Stormy's ShoBud +3, -2 changer should get Jeffrey off and running. It would be well if Jeffrey were exposed to Bent's design - among others - giving him a choice in the matter.

Didn't mean to get picky, Bent, as I took your statement quite literally - but I felt that you were sorta putting the cart before the horse.

Respectfully, as always,

Richard

[Bent]

Yes, Richard, this has been discussed before and it is the changer that is the deciding factor. Many beginners don't look at it that way though. They see a steel on stage and see it to be the usual 3.5" thickness and think that this is in fact the deciding factor. But yes: Decide if you want a triple/triple Triple/double or double/ double and size your body accordingly. Anyway, Richard, you are right again. Good job you caught it

Sure, velum paper is great if you want to go that route. This then demands more of a permanent drawing. A big 2X2 piece of Bristol board has room for four sketches of the changer end of a guitar and still have room for some measurements at each drawing.This day and age says AutoCad Inventor and that is more likely what a youngish builder will go to. Who knows, maybe Jeffrey is one of those?

[richard37066]

Bent -

My choice of Vellum does allow me to make drawings without those pesky hidden lines that sometimes get lost in the shuffle. I'm still a light box and Vellum guy since I can't afford all of that expensive AutoCad stuff. Besides, they'd have to pack it up and put it in my coffin 'cause I'd still be learning how to use it!

Do they have electrical outlets in coffins? How in hell would I get a coffee break? Woe is me.

Richard

[Jeffrey]

Hi all,
After posting I ran a search and found that this question had been asked/answered just recently. I'll know to look first, ask second next time! Sorry about that.


Bent, everything you mentioned makes perfect sense to me. I've found several pictures of fingers and I'll start measuring and drawing right away. I think I was hoping for an easy place to start. I'm not a CAD guy, although I can see how that would be a good thing to learn for designing.

Storm, if you do get the chance to measure those Sho-Bud fingers I'd sure appreciate it. It would give me a good starting point, and something to compare with while I work out the rest of the measurements.


Richard, I agree that the fingers are the starting point that all other measurements, angles and such should work from. Unfortunately for me, I've already got the body, so I'm gonna have to make everything fit to it. Its an old guitar, of Sho-Bud design (even has the gumby keyhead), and everything in it was rusted and broken. I've never seen the likes of the fingers before, they're terrible! But the body is beautiful, made of maple and cocobolo woods. So my plan is to modernize it.

I do have a couple more questions for y'all, if you don't mind? Which is a better Changer... Wraparound, or the riveted type, and why? Also, how are you guys getting those nicely bent angles on the raise and lower fingers? I've just used a hammer and vice, but they don't turn out looking nearly as good.

Thank you, everyone for the help! The brains and ability found on this forum is truly amazing!

Jeffrey

[Storm Rosson]

Yo Jeff, sorry the writing is so crude but I was kinda in a hurry (illiterate/illegible hehehe)......the measurement of 1 3/8" is from the center of the changer axle to the first raise hole, all the rest of the pull holes are 1/4" apart. ,total finger length from string bridge to bottom of finger is 2 1/4".......

shobudchanger 001.JPG (37.45 KiB) Viewed 2804 times

...keep in mind that this is a Super Pro finger, the distance from string to fretboard is 1/2", neck and changer housing thickness is 3/4",deck thickness is 3/4"........Stormy ...hope this helps bud

[Bent]

Jeffrey, My opinion is that the wraparound is the best. Why? because it gives you more throw on the finger and this in turn makes for a greater possibility of achieving those lowers that require a great throw(like lowering the 3rd G# a whole tone)

[Storm Rosson]

Jeff ,I totally screwed up on the last pic/measurements .Here is the corrected dimension/pic....Stormy

shobudchanger 002.JPG (69.28 KiB) Viewed 2775 times