Units in Mathcad

[hydromech]

Hello all...

I am familiar with gear calculations...but not with Mathcad.

I have a gear PCD and I want divide it by the module to get the number of teeth on the gear.

The PCD is in mm and so Mathcad quite rightly assumes the resultant figure from PCD/2 would be in mm.

I want it to have no units because it would just be an integer.

How can I stop Mathcad assigning units?

Mathcad 14

Thanks

Adrian

 

[israelkk]

The module should be in mm too.

 

[hydromech]

Thanks for the reply...

yes it should be in mm, but adding mm to the module makes it worse.

What was 63mm is now 6x10^4m^-1 mm...I just want it to show 63 teeth.

 

[jghrist]

It sounds like Mathcad is interpreting mm not as millimeters but as something else unrelated to length. Have you redefined mm somewhere? Maybe by mm;=1?

Attach the worksheet (Version 11) so we can look at it.

 

[hydromech]

I have attached it as v11.

Thanks for the help...

 

[IRstuff]

Why did you add units to the answers? Mathcad is simply trying to balance the units you added to the quotients.

TTFN

FAQ731-376

 

[Occupant]

This is ,obviously, not a version 11 file - that would be *.mcd and if you define Mod as mm and PCD as mm then PCD/Mod would be unitless. Isn't that what you wanted?

 

[PetieSmo]

hydromech,

Looked at your file - same comment as IRStuff: There is no need for you to add units to this answer.

To fix: Delete "mm" from behind the answer and Mathcad will give you a unitless answer, which is correct for this formula.

Peter

 

[hydromech]

It was as simple as that then...

I promised I tried to do that before I bothered you all with such a trivial issue.

Occupant...it is V14 file saved as a V11 file.

Thanks again for your help.

Regards

Adrian

 

[IRstuff]

Sorry, it wasn't saved as M11. The .xmcd extension postdates M11 and earlier, whose extension is .mcd

TTFN

FAQ731-376

 

[zdas04]

Looks like you've got your answer.

Just as a general statement, don't EVER use a variable name like "M" or "m" or "L" etc. I keep seeing people do L:45*mm and then want a volume in liters and don't understand the answer. So in your example, use M.gear:2mm or something like that. When you put the period after the variable you are adding a text label (not a subscript) that ensures that it is not a system variable.

David

 

[hydromech]

OK...thanks for the tip.