Math doesn't seem to be working

[Keith Christopher]

Panel 5 9/16 wide, by 24 1/8 tall

Opening to cover.. 11 5/8 wide, 29 3/8 tall


For the panel to be centered how wide to the rails and stiles have to be.

The math told me 3.03 for the stiles and 2.125 for the rails, but these are too short. What am I doing wrong ?

This is a raised panel door.

[Adam Strong]

Your Rails will be 5.5625 x 2.625 and the stiles will be 29.375 x 3.03125 Then you need to account for the depth of the panel grove in both. Your math is mostly fine (just not sure where the 2.125 came from, I got 2.625).

[Myk Rian]

Your Rails will be 11.625 x 2.625 and the stiles will be 29.375 x 3.03125
Did you mean to put a + sign in there, instead of an x?

[Jason Roehl]

Did you mean to put a + sign in there, instead of an x?

No, he didn't--the "x" means "by", as in Width x Length.

[Bill ThompsonNM]

the widths are ok if you correct for the depth of the groove minus
the glue space, but the rail length is way to big. If you visualize
a frame and panel you'll note that the rails are just about as
long as the panel is wide. Should be about panel width plus
the two glue spaces at the bottom of the groove (1/8 inch each
for some doors)

[Keith Christopher]

Thanks for the replies. For some reason the math didn't work for me on the rails, but It got worked out.

final dimensions stiles were 3" wide and the rails were 2 5/8 for some reason I kept getting .125 or 1/8. So there was my problem. I had already accounted for the rabbets on the panel in the dimensions I provided. It fit like a glove. :)

[Myk Rian]

No, he didn't--the "x" means "by", as in Width x Length.
....Duh... :D

[Adam Strong]

the widths are ok if you correct for the depth of the groove minus
the glue space, but the rail length is way to big. If you visualize
a frame and panel you'll note that the rails are just about as
long as the panel is wide. Should be about panel width plus
the two glue spaces at the bottom of the groove (1/8 inch each
for some doors)



Yes, you are right... I only did the math and did not sketch a layout to see this, nor did I really think any more past the numbers.


Glad you sorted it out

[John Coloccia]

I'll just throw this out there - I just purchased one of those dimensional calculators. I just got so tired of converting fractions in my head, and having to double check everything to see if it makes sense.

For some things, I've started converting over to the metric system. I'm starting to use that for instrument building where I don't generally need to worry about using standard imperial parts, bits etc.

It's not that I can't do all these conversions and arithmetic quickly in my head...I can. It's more that it interrupts my flow and forces me to do math. As a pilot, I was taught that math doesn't belong in the cockpit...too easy to make a stupid, life threatening mistake. I believe it doesn't belong in the shop either. Maybe while drawing up plans, but not in the shop.

Just my opinion, and somewhat off topic from the OP :D

[Jason Roehl]

Sorry to hijack a little bit (sorry for the term, John), but I was wondering what an example is of a situation where a pilot COULD use math in the cockpit, but does it another way instead. I understand the basic concepts of flight and aircraft control, but have never had any pilot training whatsoever, unless you count Chuck Yeagers Flight Sim of the late '80s, MS Flight Sim and Falcon 3.0/4.0. :D

[David DeCristoforo]

These calculations will vary based on the depth of the cope and stick cut. The rail length is the net width of the door minus 2X the rail width plus 2X the depth of cut. So if you have a cope and stick cutter that has a net depth of cut of 3/8" (.375) and 3" wide rails, and assuming a net door width of 12" you get:

3" X 2 = 6"
12" - 6" = 6"
2 X .375" = .75" (3/4")
6" + .75" = a 6.75" Rail

Extrapolate from that and your "standard" deduction for rail length from any door width will be 5.25"

But keep in mind that this needs to be adjusted for the actual cope depth. 3/8" is typical but I have some that are 5/16" and some that are 7/16. Plus I use T&G cuts of varying depths so allowances have to be made for that.

[John Coloccia]

Sorry to hijack a little bit (sorry for the term, John), but I was wondering what an example is of a situation where a pilot COULD use math in the cockpit, but does it another way instead. I understand the basic concepts of flight and aircraft control, but have never had any pilot training whatsoever, unless you count Chuck Yeagers Flight Sim of the late '80s, MS Flight Sim and Falcon 3.0/4.0. :D


Sure! It mostly has to do with figuring out headings, and things like that. For example, it's far simpler to simply glance at the directional gyro to figure out reciprical headings than it is to add or subtract 180 degrees. There are other cases too but it would require explaining how different navaids work, what the needles mean, wind corrections, etc. It's very true, though, that's it's far simpler to pick off headings visually than it is to try and calculate them in your head.

And then there are the E6b calculators that allow you to twist a dial and very quickly calculate speeds, distances, times etc.

Here's another case. You're flying heading 135, and someone calls out "Cherokee 12345, 3500 feet, 2 miles Northeast of whatever airport...". Which way do you look to spot him? Sure, I can figure it out. It's much easier to look at a compass rose to figure out he's behind me and to the left.

[Dan Forman]

I find that something about my shop seems to defy the laws of mathematics, They break down all of the time. Must be some kind of warp in the space-time continuum. :)

Dan

[Jason Roehl]

Thanks, John! Makes perfect sense! K.I.S.S. at work...