View Full Version : Misc Needing a math formula

Over-Head

02-01-2011, 04:54 PM

I rememebr back in school there was an equation which I can figure out how long the arc of a circle is from the 0-90-180-270 sections? c= (pie) x d

Is there a formula which you could work to deturmin how big an arc you need, or just work the same one backwards?

Math wasn't my strong point in school

Say I'm running a 2 ring medallion with an outer script.

Radius ring 1 = 18 inches

Radius ring 2 = 42 inches

Client would like me to run a script around the outer ring about 6 inches away from the second medallion.

each script section is a certian lenght, and I want even spacing between them.

C= pie x d

then just divide it would tell me how long each section is, will working it backwards do the same thing?

I'm figuring it will

I tried dumping Antifreeze on my loose leaf, then hanging it up to dry with nutt hooks....didn't help.:D

Jenson71

02-01-2011, 04:57 PM

I tried dumping Antifreeze on my loose leaf, then hanging it up to dry with nutt hooks....didn't help.:D

Did your loose leaf come from an AIDS tree?

Crush

02-01-2011, 05:00 PM

http://img.photobucket.com/albums/v84/kontxouso/GifScanners.gif

Over-Head

02-01-2011, 05:01 PM

Did your loose leaf come from an AIDS tree?

couldn't tell ya. Normally I do a live mock up in 1/4 sections on site, I'm designing this one for a house 6500 miles away

notorious

02-01-2011, 05:03 PM

Diameter x 3.14 / 4 = each 90 degree length.

If I read you question right, the diameter of the outside Medallion is 84 inches. 6 inches out from each side would equal 96 inches.

Diameter is 96. 96 x 3.14 = 301.44 for the circum.

Circum/4 = 75.36 inches per 90 degree section

If I read your question right, this is your answer.

Extra Point

02-01-2011, 05:07 PM

Arc length of 90 degree swept angle=3.1416*d/4=.7854XD

Double the angle, double the arc length.

Is that about it?

Over-Head

02-01-2011, 05:11 PM

Diameter x 3.14 / 4 = each 90 degree length.

If I read you question right, the diameter of the outside Medallion is 84 inches. 6 inches out from each side would equal 96 inches.

Diameter is 96. 96 x 3.14 = 301.44 for the circum.

Circum/4 = 75.36 inches per 90 degree section

If I read your question right, this is your answer.

Yep.

ok, question,

if you work the equation backwards from the starting point of

I want to add multiple peices each X number of inches long,

with an equil spacing around the ring.

Can I take the length of the piece, plus the spacing, and create a ring that way as certian peices are different lengths.?

The 6 inch spacing from the outer ring was for the sake of a number, It might have to be 7 or 5. This is what i'm trying to figure out "on paper"

notorious

02-01-2011, 05:17 PM

Yep.

ok, question if you work the equation backwards from the starting point of

I want to add multiple peices each X number of inches long,

with an equil spacing around the ring.

Can I take the length of the piece, plus the spacing, and create a ring that way?

The 6 inch spacing from the outer ring was for the sake of a number, It might have to be 7 or 5. This is what i'm trying to figure out "on paper"

I am not the best at creating equations, just practical application.

I was the kid that the teacher didn't like because I could give her correct answers without using equations.

Practically speaking, I would figure your spacing between each ring and figure your equation mutiple times until you have the desired amount of rings.

Over-Head

02-01-2011, 05:22 PM

I am not the best at creating equations, just practical application.

I was the kid that the teacher didn't like because I could give her correct answers without using equations.

Practically speaking, I would figure your spacing between each ring and figure your equation mutiple times until you have the desired amount of rings.

Thanks.

Math was never my strong point, and truth be known if it wernt for a certian photo the appeared from a teachers staff party my band played at in a bar one christmass, i'd never have gotten the 3 points I needed for a math credit to graduate :evil:

Hell I spent more time in the hall than I ever did in math class, and from Grade 8 summer school, right to grade 12 I never did pass a year in math.

Sure hating myself fot it 25 years later let me tell ya!!

notorious

02-01-2011, 05:26 PM

Sorry, I just read your edited post.

It would take me awhile to think a linear equation to figure that out.

How many rings do you want?

What is the desired outside diameter?

What is the desired inside diameter?

cdcox

02-01-2011, 05:40 PM

Not sure if I understand the question but here goes.

If the circle has a diameter of d the circumference of the circle is

C = pi * D

Now unroll the circle so it lays out flat.

The circumference must equal the sum of the pieces plus the spacings with everything laid out flat and straight. If your pieces are already curved, you could measure their flat length with a flexible tape or something.

Over-Head

02-01-2011, 05:40 PM

Sorry, I just read your edited post.

It would take me awhile to think a linear equation to figure that out.

How many rings do you want?

What is the desired outside diameter?

What is the desired inside diameter?

Yeah, sorry about that. I realised I had forgotten "part" of the question when I posted it...(hey Raiders fans aint too bright ya know !!)

This currant project will ues the exact dimensiuons of a past one. (room size just worked out that way.)

More of a "if i'm in this situation, how do you figure it out".

So a linear equation is what i'm looking for...got it.

If I had even know what to call it, I could have started googling.

notorious

02-01-2011, 05:54 PM

Yeah, sorry about that. I realised I had forgotten "part" of the question when I posted it...(hey Raiders fans aint too bright ya know !!)

This currant project will ues the exact dimensiuons of a past one. (room size just worked out that way.)

More of a "if i'm in this situation, how do you figure it out".

So a linear equation is what i'm looking for...got it.

If I had even know what to call it, I could have started googling.

When I put in a wood floor that has some wild designs, it's off to the drafting board

If I were doing circles in ring radiating from a point, I put a screw in the center, measure and cut the string to a desired length and a attach a pencil. You can tweek the length by screwing/unscrewing the line around either the screw or pencil (I prefer the line around the screw to just be looped, that way it doesn't have a very small change in length as it wraps around).

The more rings you add, just cut a new line that much longer and remark the line.

I hope this helps. Sometimes I run into a wild shape that will screw with me a little bit, and I work on something else while I think about it. Next thing you know it becomes very simple.

Over-Head

02-01-2011, 06:06 PM

Not sure if I understand the question but here goes.

If the circle has a diameter of d the circumference of the circle is

C = pi * D

Now unroll the circle so it lays out flat.

The circumference must equal the sum of the pieces plus the spacings with everything laid out flat and straight. If your pieces are already curved, you could measure their flat length with a flexible tape or something.

Pieces are stright, by placement, and design I create the illusion, of them arcing

Thanks

Never hurts to double check with folks who actually know math, then guess at it.

Over-Head

02-01-2011, 06:11 PM

When I put in a wood floor that has some wild designs, it's off to the drafting board

If I were doing circles in ring radiating from a point, I put a screw in the center, measure and cut the string to a desired length and a attach a pencil. You can tweek the length by screwing/unscrewing the line around either the screw or pencil (I prefer the line around the screw to just be looped, that way it doesn't have a very small change in length as it wraps around).

The more rings you add, just cut a new line that much longer and remark the line.

I hope this helps. Sometimes I run into a wild shape that will screw with me a little bit, and I work on something else while I think about it. Next thing you know it becomes very simple.

Basically the same spinning medallions on the ceiling, you just need a fixed center point that everything runs off.

Most the stuff I do, is done on site, and I have extensive notes on past ceilings i've done for re-creation.

While great for former projects, as I expand my line, all my pieces to teh puzzle change as well.

I have a friend of mine getting me a copy of a computer program he uses for designing graphics which suposewdly will do it all for me.

But I always like having a pen and paper back up just in case.

notorious

02-01-2011, 06:44 PM

Basically the same spinning medallions on the ceiling, you just need a fixed center point that everything runs off.

Most the stuff I do, is done on site, and I have extensive notes on past ceilings i've done for re-creation.

While great for former projects, as I expand my line, all my pieces to teh puzzle change as well.

I have a friend of mine getting me a copy of a computer program he uses for designing graphics which suposewdly will do it all for me.

But I always like having a pen and paper back up just in case.

You have 3 dimensions to worry about. I only have 2. :)

Your work is very impressive, BTW.

acesn8s

02-01-2011, 06:56 PM

C= pie x d

then just divide it would tell me how long each section is, will working it backwards do the same thing?

I'm figuring it will

I tried dumping Antifreeze on my loose leaf, then hanging it up to dry with nutt hooks....didn't help.:DIt depends on what type of pie we are using. Cherry pie and pumpkin pie have different consistencies and could change the factors enough to give you a headache. However, if we use hair pie then the results would be very unpredictable. Of course this could be avoided if you were to use pi.

Hog Farmer

02-01-2011, 07:02 PM

I always take the volume of ejaculate in ML and multiply it times the concentration of sperm and then divide it by 3 billion to give me the number of doses I can use to inseminate my females.

hope that helps.

notorious

02-01-2011, 07:03 PM

Oh, don't forget to include the width of the lines.

Over-Head

02-01-2011, 07:17 PM

Oh, don't forget to include the width of the lines.

The lines just give me a refrence point to `guess`the flow.

My plaster medallions can go any where from a 1 or 2 inch wide outer accent ring to 12inch or larger width `King Edward` centerpiece.

It`s not so much the mesurments have to be dead on like say a custom floor where a run out of half and inch to an inch can throw a room off. Or trim work which needs to be within a 64th or better.

If i`m within half to and inch and a half on center, it generally works.

My stuff is more of Ět looks right`put somewhere about *here*, now make the rest of it flow and fit the room.

And thanks for the complaments

Over-Head

02-01-2011, 07:19 PM

I always take the volume of ejaculate in ML

.

Does my hart good to see a Yankie Doodle use Metric for measurments and catch up with the rest of world :D:clap::D

Over-Head

02-01-2011, 07:22 PM

It depends on what type of pie we are using. Cherry pie and pumpkin pie have different consistencies and could change the factors enough to give you a headache. However, if we use hair pie then the results would be very unpredictable. Of course this could be avoided if you were to use pi.

Would the thickness of the apples skin affect the total offset spacing....damn me and my piss poor spelling.

Cant add, can`t spell, no wonder I root for Silver and Black :D

notorious

02-01-2011, 07:27 PM

The lines just give me a refrence point to `guess`the flow.

My plaster medallions can go any where from a 1 or 2 inch wide outer accent ring to 12inch or larger width `King Edward` centerpiece.

It`s not so much the mesurments have to be dead on like say a custom floor where a run out of half and inch to an inch can throw a room off. Or trim work which needs to be within a 64th or better.

If i`m within half to and inch and a half on center, it generally works.

My stuff is more of Ět looks right`put somewhere about *here*, now make the rest of it flow and fit the room.

And thanks for the complaments

Ah-Ha....

I understand it now. You are dealing with Art, and I am thinking Geometrics. You need that visual boundry that the circles create to assist you in the freehand aspect of your design. It would probably be damn near impossible to just draw out something that large and have it anywhere near balanced without references.

As for the compliments, they are well deserved.

Bwana

02-01-2011, 08:34 PM

Your work is very impressive, BTW.

Yep, kick ass work OH.

When I put in a wood floor that has some wild designs, it's off to the drafting board

If I were doing circles in ring radiating from a point, I put a screw in the center, measure and cut the string to a desired length and a attach a pencil. You can tweek the length by screwing/unscrewing the line around either the screw or pencil (I prefer the line around the screw to just be looped, that way it doesn't have a very small change in length as it wraps around).

The more rings you add, just cut a new line that much longer and remark the line.

I hope this helps. Sometimes I run into a wild shape that will screw with me a little bit, and I work on something else while I think about it. Next thing you know it becomes very simple.

I use way more math in estimating flooring jobs than I ever thought I would need to know back in high school. Some remedial geometry/algebra would probably be helpful but I doubt I'll ever get around to it.

Rain Man

02-01-2011, 09:10 PM

I don't quite understand the question, but if you can draw it I can probably help. I like geometry and trig and stuff. Unless notorious or someone else has already solved it and you're just chatting now.

Over-Head

02-01-2011, 09:16 PM

Ah-Ha....

I understand it now. You are dealing with Art, and I am thinking Geometrics. You need that visual boundry that the circles create to assist you in the freehand aspect of your design. It would probably be damn near impossible to just draw out something that large and have it anywhere near balanced without references.

As for the compliments, they are well deserved.

Both kinda, geometric art, ...which is why my origional question now don't seem so stunned, as much as the back aswards way I asked it.

Worst of it is, I can look at almost ANY ceiling, and within a matter of seconds, I already have a design in my head.

My next process is usually, take a pencil, and walk around under the ceiling , loosly drawing it out.

If my "squigly lines" kinda somewhat look like what I had in mind,,,I start laying plaster.

And figure the math out as I go.

.

Over-Head

02-01-2011, 09:28 PM

I don't quite understand the question, but if you can draw it I can probably help. I like geometry and trig and stuff. Unless notorious or someone else has already solved it and you're just chatting now.

In a nut shell Kevin

you have gum drops, chaulk erassor, Pez dispencer, what ever.

Your client says "hey, that would look real cool going around in a circle just outside that $15,000.00 light fixture.

-You already know the first ring will be roughly a fixed diameter.

-Your second ring (if applicable) will be spaced out further to "look astecitly" correct.

- You know you'd like to put the (what ever) roughly 6-8 inches out side the Outer ring, but your not too sure how many you need, or how far off the second ring to place them.

Maybe I did actually complicate the way I tried to ask teh question, but is there an easy way to figure out

Ok, my what ever is x in length (which you cant change) how far out do I need to go to allow for equil spacing (or equil lenght spacings) of the objects.

is it just bacisally C= pi d in reverse where your trying to determin your Radius or Diameter to see how many you would need.

After you make a "trial mark", deturmine the lenght of the D, then divide.

I pretty much got it now.

Kinda what I thought, but wanted to throw it out there to someone MUCH better at math, or engenering per say than myself.

vBulletin® v3.8.0, Copyright ©2000-2015, Jelsoft Enterprises Ltd.