the Fly Clone Project

hey guys, i have a couple of flat springs, and i noticed that I have two different 9 gauge springs that look completely different and so i'm wondering if one of them was mislabeled somehow. its like they are slightly different shapes/sizes. one of the nines has the "9" written in black sharpie marker so its hard to see. i've included some pics, the first pic is of the 9 spring with a 10 spring next to it, and then i have another pic of the first 9 i have close to the second 9 where you can see how different the two nines look together. and then i have a side view so you can see the 10 spring's thickness next to the 9 spring's thickness. to me the larger 9 spring looks closer to a 10 gauge spring, however in the side view pic it does appear the 10 spring might be ever so slightly thicker than the "large 9 spring"(the 10 gauge spring is on the right side in the side view pic). is it common for various different 9 gauge springs to be different shapes/sizes sometimes?

here's the pics...

9 and 10 next to each other:


9 and 9 side next to each other:


9 and 10 side views:

Apologies for the late reply, @ubik55. I measured a few of my spare springs, rated 9, 10, and 11:

W = Width measured at end, middle, end
L= end-to-end length

[measured in inches because I'm not being the least bit scientific with this ]

9 W 1.506" 1.505" 1.505" L 3.063"
9 W 1.506" 1.506" 1.504" L 3.117"
10 W 1.506" 1.505" 1.504" L 3.095"
11 W 1.338" 1.337" 1.338" L 3.134"

I found the measured thickness to generally be the expected .025" stock, with deviations of +/- .001" found at random points in each spring attributable to user error.

I've read various, contradictory accounts of how the Parker factory incarnations arrived at the ratings sharpie'd on each spring; with none seeming particularly accurate (e.g. "We had a jig to test if each spring could counterbalance 114lbs of tension", "most springs we received were unusable", "Excel perfected the process with zero failures", etc.).

I’ll just add to what Mark has shared, but—stating the obvious—there is a lot to this, but the physical size of the spring, though an observable factor, is not in itself an indicator of how the spring will operate (or its rating).

If your spring floats the bridge properly with a set of strings then it works—the label or any other markings on the spring are not in itself a guarantee that it will operate as it ought to operate.

mmmguitar wrote: Sat Dec 09, 2023 3:09 pm 9 W 1.506" 1.505" 1.505" L 3.063"
9 W 1.506" 1.506" 1.504" L 3.117"
10 W 1.506" 1.505" 1.504" L 3.095"
11 W 1.338" 1.337" 1.338" L 3.134"

Oh wow, okay well that's helpful, thank you. It would seem yea there is some variation in the springs, but hmm... its just strange seeing most springs have the silver sharpie labeling and then a few oddball ones with black sharpie labeling, makes me feel like its less authentic when its just a black "9" written on it, hah. But yea I guess the silver sharpies do cost more, if that was a factor back then... lol. Black sharpies are way cheaper!

vjmanzo wrote: Sat Dec 09, 2023 4:26 pm I’ll just add to what Mark has shared, but—stating the obvious—there is a lot to this, but the physical size of the spring, though an observable factor, is not in itself an indicator of how the spring will operate (or its rating).

Yea it would seem there are manufacturing tolerances that Parker went by which makes sense, no two springs will ever be the exact same. It's kind of like metal springs in microswitches for gaming mice. No two M1/M2 buttons on two identical mouse models will ever feel the exact same I've noticed.

I had measured my pre-refined springs for a 97 Artist and a 99 Deluxe some time ago. The difference I saw was in the width of the springs and not of the length or thickness of material. If this is the case with all production runs of original Flys, then I thought it was an ingenious way to handle the various tensions by using the same alloy/shape and adjusting the width for various string weights. Since I like 9.5's, I stayed with the 9 spring since I lightly use the vibrato and it also gave a lighter touch to it's operation for my tastes. The photos in the first post really nail what I had discovered some time ago. It shows that the "black marked 9" is actually a 10. The overall length isn't going to matter because of your adjustment wheel. Also, see the bend angle on each in photo 1? That, plus whatever use each spring has had or not had, can make some differences as seen in the length but are of no consequence, in my not-so-humble opinion.