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I know some of you have bought a set of the OM plans from the forum. I am in process of drawing the SJ plans and am looking for feedback and suggestions that my need incorporated in the SJ plans. So let me know what you think or need added.

[QUOTE=MichaelP] I know some of you have bought a set of the OM plans from the forum. I am in process of drawing the SJ plans and am looking for feedback and suggestions that my need incorporated in the SJ plans. So let me know what you think or need added.[/QUOTE]

All that I can see that needs to be added is more and bigger walls in my shop The last plans look great and I don't personally see anything that needs to be added. Nice job Michael.

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Don Atwood
Arlington, VA

Sorry about your shop walls but what good are a set of guitar plans if they are not full scale?

Michael plans came today and really nice and easy. I do different than most probably, but use decimals rather than fractions, but that isn't a problem, I will just write the decimals next to fraction and have both for reference. Thanks and great work. WELL WORTH IT FOLKS

I would like to see measurements in millimeters as well.

[QUOTE=Robbie O'Brien] I would like to see measurements in millimeters as well.[/QUOTE] We can do that with no problem. I actually thought about that after the release of the OM. The SJ will be in both in. and mm. Good sugestion.

Michael, Or others John K probably knows math better than most from physics. I know the formula and how to convert fractions into decimals. What if formula or converting decimals into fractions. I do entirely decimals. I was a land surveyor and draftsman as one of my cop moonlighting careers TIA

[QUOTE=stan thomison] Michael, Or others John K probably knows math better than most from physics. I know the formula and how to convert fractions into decimals. What if formula or converting decimals into fractions. I do entirely decimals. I was a land surveyor and draftsman as one of my cop moonlighting careers TIA[/QUOTE] It is real easy for me to give dims in 3 formats per one dim line. I was thinking of giving dims in inches frac, inches dec. and mm. this takes no time difference and very very little space. I think this would be convenient for beginners, journeymen and our European members and visitors all.

Heck I don't mind converting the fractions, kind of fun sometimes to sit back and do that on other things. Just don't know how to do the fractions to decimals

I spent so many years as a draftsman that I still have most fractional/decimal conversions memorized. Still, if buying a plan, my preferance would always be decimal inches. Never could get used to the metric system...

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

I like MM's for measuring fretboards. It is so much better than fractions or decimals, which are actually two measurements, the whole inch, plus the decimal equivalent of the fractional inch. So it's just easier to read it in millimeters, for fretboards at least. Of course the same is true when get into partial millimeters.   

Neither system translates to the other evenly, you always have to settle for the "closest" conversion which can be akward. I prefer the English system but don't much care either way as long as it's consistant.

[QUOTE=stan thomison] Heck I don't mind converting the fractions, kind of fun sometimes to sit back and do that on other things. Just don't know how to do the fractions to decimals[/QUOTE]
Stan it's easy. Just divide the upper denomonator by the lower. for example to convert 1/8" to decimals 1 divided by 8 = .125 , 1 divided by 4 = .250 etc.Bobc38376.8619328704

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Sorry had it backwards meant formula for converting decimals to fractions

I'm comfortable with either system as well. However, when an instrument is designed, it is going to be either an English design or a Metric design. If both units are given, one will be reasonable, ie 1-7/8 whereas the other will be strange. ie 47.45mm

It is even weirder going from mm to english fractions. For example 2cm is just about 4/5 of an inch. But we don't use 5ths in the English system. How do we convert 4/5th into the nearest English fraction? The simplest way I know is through successive approximation.
4/5 = .8
.8 is greater than 1/2 so there is one 1/2 in .8.
We subtract the 1/2 from the .8
.8 - .5 = .3
There is one 1/4 in .3 so we subtract it from .3
.3 - .25 = .05
There are no 1/8ths in .05
There are no 1/16th in .05
1/32nd is .03125 so there is one 1/32nd .05 so we subtract that.
.05 - .03125 = .01875
1/64th is .015625 so there is one 1/64th in .01875 so we subtract that.
.01875 - .015625 = .003125
That is as close as I want to get so I will represent the value as 64ths.
1/2 + 1/4 + 1/32 + 1/64
32/64 + 16/64 + 2/64 + 1/64 = 51/64th
2cm = 51/64 approx.

All in all, it is not worth it. If you have a plan that is metric, get a meter stick.

OF course 2cm is closer to .787 inches and the result is closer to 25/32nds with a resolution of 1/64th.
Mike Mahar38377.3611689815

I'm afraid that eventually it will be a case of bowing to the inevitable, Metric is the future. It has the great advantage in being a purely decimal system no 7/16ths 38/64ths to deal with. When dealing in Inches I only ever use inches and thousanths of an inch thus converting the Imperial (English) system into a metric system. One of the most costly errors NASA ever made involved both European and US manufacture in one satellite. Unfortunately the US engineers converted the metric plans to English measurements in the software design and the whole project once launched became hundreds of dollars of flying junk!

By the way in English schools the English system hasn't been taught for 20 years!

Colin

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I don't believe in anything, I simply make use of a set of reasonable working hypotheses.

Was this Hubble? I remember there being a mathematical error grinding the lense. Required a space mission to replace the lense or give it corrective vision? Hmmmm. So sad it's going to die.

I have heard for the past 30 years that English measuring system was history. That the Metric system would become the standard in the U.S.. I have to tell you that a system that is built on increments of 10ths of units is easer and in many ways more accurate than a system of fraction based on 128ths, 64ths, 32nds,16ths and so on. Now that's apples to apples. On the other hand, metric decimal to U.S. decimal is a different situation. You can be just as accurate with either. And this is the reason the push to convert to the metric system died here in the U.S. in the 1980's There is just too much money tied up in tooling based on the U.S. decimal system to justify the change with no real gain in accuracy. After 30 years in the engineering side of the manufacturing I have yet to see it happen in any major way. I don't see a conversion to the metric system here in the U.S. happening in my life time.

What is funny we do alot of inches with the decimals in luthery or mm also, but try and find a good ruler with decimals. Stew Mac and others have rulers but they are only in mm, 32nds and 64th. I had to go to an engineering supply place to find mine in decimals and fractions. Maybe a ruler with all 3 would work say in 32nd, .000's and mm

Yeah Michael, I was thinking the exact same thing. In college I was a physics minor and all we ever used was metric. It felt awkward to use anything else.

However, in the wood working world I am comfortable either way, but I have such an investment in tools that there is no way I would switch. I suspect businesses / engineering / manufacturing are in the same boat. It is just too expensive to change with no (substantial) net benefit.

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Brock Poling
Columbus, Ohio
http://www.polingguitars.com

The English system is based on the principle that it is often useful to divide things in half and then again divide that in half. The metric system doesn't care about that (mostly). I remember the first time I went to Europe and ordered a beer. On the glass was a mark showing that the glass had .4 litres in it. Up until that point it had never occured to me that people would choose sizes based on their measuring system. (I can be a bit slow at times). I just thought that they would have half a litre, 1/4 litre, 1/3 litre, etc. I have since seen bottled water in .33 litre bottles while in Holland. (Spa Blau, I think)

The metric system does, in fact, care about halfs. If it was fanatical about being decimal they wouldn't mark their pecision rules at .5mm intervals. They would make them at .1mm intervals. Of course you wouldn't be able to see the lines without a magnifying glass. Meter sticks have the fifth mm between the centimeter marks a little longer just so you don't mis count the millimeters. I found a metric ruler that didn't do this almost unusable. I could never convince myself that I had counted the lines correctly. "Was that six or seven ticks.?"

Quite. I'm only familiar with both 'by force', mostly because almost all guitar measurements are given in both measurements. I tend to also know the conversions without doing the math these days. The thing is, most fractional inches don't mean anything to me, while a size in metric will have me going 'oh, that big!'.

I've got a nice steel rule with metric on one side, fractional inches on the other, which is handy sometimes. For rough, large dimensions, inches are nice and simple. For detailed, small measurements, it's gotta be mm. If I'm laying out a fretboard, it's not even a question which one makes most sense.

I guess being an engineer and having worked with both most of my life it is easy for me to think of a unit being a unit. you could drive your self crazy trying to remember conversion factors. Plus when converting with conversion factors you add rounding error into the equation. Be sure to use a decmal with enough places so that entire decimal equivalence of the fraction is used. Example 5/16" = .3125 x 25.4 = 7.9375mm. However rounded to 3 decimal places 5/16 = .313" x 25.4 = 7.9502mm a rounding error of +.0127. In a fretboard this could bit you quick and keep add up as you go further down the fretboard.

I'm with ya Mattia of MM for FB's. Of course if you buy the template from LMI or StewMac, then well, it's a moot point....

Bruce: that's certainly true, and I do gots one. But I've been 'adding' lower frets to the templates I have for my baritone, and I'll be adding one for a long-scale medium jumbo I'll be making, so I gots to measure at least two or three fret slots real darn accurate-like :-)