Scale to weigh guitars

[CoreyT]

Sometimes I see threads on here from the PRS dealers with the weight of their guitars listed, and also a pic of the guitar on a scale.
What is a good scale to get for doing this?
Something like this perhaps?
http://www.amazon.com/American-Weig...8&qid=1453199568&sr=8-1&keywords=postal+scale

Amazon lists quite a few.
http://www.amazon.com/s/ref=nb_sb_n...keywords=postal+scale&rh=i:aps,k:postal+scale

 

[Fro]

Go to your local Walmart or sporting goods store and get a fish scale. It'll have a nice little hook that you can hang on a peg head or a loop of string around the headstock.

 

[CoreyT]

Thanks, I ended up ordering that postal scale as I want to be able to lay the guitar down flat on top of my guitar case cabinet.
Easier to weigh that way instead of having to hold the fish scale in one hand.

 

[Kynlore]

I'm not sure how accurate you are looking to be, but if you are laying it flat it will show lighter than it really is. Standing it on end and supporting it with your hand may give more accurate results with that type of scale.

 

[rugerpc]

I'm not sure how accurate you are looking to be, but if you are laying it flat it will show lighter than it really is. Standing it on end and supporting it with your hand may give more accurate results with that type of scale.

Ummmm...

Huh?

 

[Kynlore]

Ummmm...

Huh?

If you are trying to weigh a guitar flat on a 6"x6" scale you aren't going to get an accurate representation of its weight with the rest of it hanging off the side, to say nothing of the neck and headstock. Putting it on a case and putting the case on the scale will disperse the weight even more.

If you want to be accurate you need a scale that is big enough to the support the entire mass of the guitar or a hanging scale as suggested above.

 

[rugerpc]

If you are trying to weigh a guitar flat on a 6"x6" scale you aren't going to get an accurate representation of its weight with the rest of it hanging off the side, to say nothing of the neck and headstock. Putting it on a case and putting the case on the scale will disperse the weight even more.

If you want to be accurate you need a scale that is big enough to the support the entire mass of the guitar or a hanging scale as suggested above.

Ummmmmm...

Huh?

Are you saying that parts of the guitar hanging over the edges of a scale and not touching anything else but air somehow don't contribute to the mass seen by the scale?

 

[Kynlore]

To some degree, yes. I'm not saying it's invisible. I'm saying it's reduced.

The neck and headstock handing off the end will create a fulcrum and counter the body, causing a slight lift of the body, reducing what the scale reads.

 

[rugerpc]

To some degree, yes. I'm not saying it's invisible. I'm saying it's reduced.

The neck and headstock handing off the end will create a fulcrum and counter the body, causing a slight lift of the body, reducing what the scale reads.

So, this Tele actually weighs more than 6.59 lbs?? How much more?

Please tell us more!

 

[watelessness]

Fish scale all the way. It's very convenient for taking to stores and PRS Experiences.

And I also call shenanigans on Mr Kynlor's proposed laws of physics

 

[rugerpc]

words...

I'm loving that YOU weighed in on this...

 

[László]

Kynlor's Theorem postulates that if the square of the hypotenuse is exceeded by the angle of the dangle, the fish scale is the tool to wrangle.

However Ruger's First Law Of Scale Dynamics states that it ain't weighed until it's laid.

Ruger's First Law of Scale Dynamics won him the Nobels Prize:

I don't see how we can refute the First Law.

Yeah, Kynlor you should probably have stayed awake a little longer in Physics class...

 

[Dusty Chalk]

If you want to be accurate you need a scale that is big enough to the support the entire mass of the guitar or a hanging scale ...

Correct, but if you move the guitar so that the center of mass is above the platform, it doesn't matter how much is hanging over the edges, as long as the entire mass of the guitar is supported by the platform of the scale.

A postal scale should be fine.

 

[CoreyT]

Not looking to weigh a guitar case too, just the guitar.
So if Kynlore's theory is correct, then all the vendors on the site here who weigh their guitars and show us pics of the guitars sitting on a scale are wrong then and their ads are false?

 

[Dusty Chalk]

Except it isn't, so...no worries.

<-- has a degree in Physics

 

[AP515]

<--- Also has a degree (in engineering), and there is also one more thing to consider. If the weight is not centered on the scale (center of mas at center of scale, the reading can be off because internal to the scale the weight is shifted. Try standing "mostly" on one foot and see how much the scale moves around. The weight needs to be stable. If stable, the reading will be correct if the guitar is free standing.

 

[CoreyT]

On the scale above that I just bought you can see it has a big enough surface to lay down not just a guitar, but also big boxes that can overhang.
People are using this brand of scale daily to ship out packages via Ebay.
I would think with this style of scale you could put just about anything on it so long as nothing touches the lower base since it is just the top part of the scale that does the weighing.
Much different than a bathroom scale.

Anyways, this is going to be a fun project for me as I want to record the weight of each of my guitars.
I already know which one will be the heavyweight, that would be the SE Tremonti Custom, and the lightest will either be the little Fernandes, or the Gibson SG.

 

[Dusty Chalk]

<--- Also has a degree (in engineering), and there is also one more thing to consider. If the weight is not centered on the scale (center of mas at center of scale, the reading can be off because internal to the scale the weight is shifted. Try standing "mostly" on one foot and see how much the scale moves around. The weight needs to be stable. If stable, the reading will be correct if the guitar is free standing.

Yup -- depends on how the scale is engineered, it might read different if the shaft (of the scale, the shaft holding up the platform) is frictioning* against something, or if there's torque somewhere else.

Hopefully the center of mass will be over a flat surface that you can balance on the scale. Worst case you might need to put something like a pillow to keep it stable, and then subtract the weight of the pillow.

 

[rugerpc]

I was hoping to hear the "physics" behind Kynlor's post, you know, the pound of feathers stuff...

But what is really going on isn't that hard to understand.

Guitars, like everything else in the world, have a single balance point for each orientation. Place the balance point over the center of the scale platform. (See pic in post 9) It doesn't matter if the platform has a single central shaft or multiple "voting" shafts, the weight will be accurate within the tolerance of the scale.

 

[toothace]

What Ruger said...If the guitar is balanced on the scale, isn't the center of mass over the scale, so it's giving a correct weight?

< has neither a physics nor engineering degree, but was adult Pinewood Derby champ 2 years in a row.( so I know how to manipulate a scale)