stupid technical question

[salrcr42]

I have read alot of posts concerning the "X" demension of props and outdrives. how did the term X become X. understanding in the law of math an "X" is condsidered a variable determined by a function of other variables, but why not call it a "Y" dimension?
How and why in boat rigging did this become an X demension?
I know some of you can set me straight pretty quick.

[MOBILEMERCMAN]

X marks the spot. I don't think it has anything to do with math terms.

It is for determining where to drill and cut the transom. It is the spot where the vertical and horizontal center lines meet on the transom. It is needed to position the template or cutout fixture for drilling and cutting. Many times the term of X dimension is used incorrectly.

Here is a drawing that shows the X dimension.

[salrcr42]

thanks jim, i had a feeling you would answer....

[salrcr42]

also adding that people raise the "x" dimension.. you can raise it with adapters/ spacers... the transon is already drilled... does it now become a "Y" dimesion since the transom is already cut?

[MOBILEMERCMAN]

Propshaft height is a more accurate term.

[Geronimo36]

Let's confuse some more... Let's call it a "t" dimension... lol

[Geronimo36]

I have read alot of posts concerning the "X" demension of props and outdrives. how did the term X become X. understanding in the law of math an "X" is condsidered a variable determined by a function of other variables, but why not call it a "Y" dimension?
How and why in boat rigging did this become an X demension?
I know some of you can set me straight pretty quick.

It's the intersection of your X and Y axis points on the transom.... Your X axis is your horizontal plane from which everything else get's measured. I can see what ya mean by why not a Y but the measurement of "Y" determines the height of "X"; http://www.we-r-here.com/cad/tutoria...es/xy_axis.gif

That's why builders will say you have a 17" X dimension (horizontal Axis) on 35" centers (vertical axis).

[Griff]

also adding that people raise the "x" dimension.. you can raise it with adapters/ spacers... the transon is already drilled... does it now become a "Y" dimesion since the transom is already cut?

When people say that, that is one of the times that the term X dimension is used improperly. The X dimension remains the same unless the transom is recut and the engine is also raised or lowered.

What they are doing with spacers and/or shorty drives is changing the propshaft height. This is much easier than chnaging the actual X dimension and allows for testing with various propshaft heights.

[salrcr42]

It makes a little more sence especially since the diagram from the manual posted above actually has it labeled "x" which I guess makes it an "x" demension.
Thanks all for the input...

[jeffswav]

I just changed my x dim on my boat. I replaced the entire transom and recut the hole 3" higher. It is well documented under the "construction and finishing" section. The thread is "Raising the x" check it out. Geronimo also raised his last year.

[Chris]

And if you really want a piece of truly arcane but relative information, it's called the Cartesian Coordinate System.

[salrcr42]

And if you really want a piece of truly arcane but relative information, it's called the Cartesian Coordinate System.

Which in my opinion by raising the prop hieght would be a "Y" dimension.
which was my confusion to start with..

[Tony M]

Which in my opinion by raising the prop hieght would be a "Y" dimension.
which was my confusion to start with..

Who's on First , and Y .

[catastrophe]

And if you really want a piece of truly arcane but relative information, it's called the Cartesian Coordinate System.

I've finally figured it out......someone fished you in to buying a set of encyclopedias a long time ago.