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Forum topic by Partridge posted 04-10-2008 09:22 PM 1374 views 0 times favorited 25 replies Add to Favorites Watch
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Partridge

296 posts in 2623 days


04-10-2008 09:22 PM

I know we live in a world of Google Sketh and this is easy to finger out but i do not have a computer in shop so.

I am putting a box together and the ends are tilted 10 deg. and flush with edges. So if the sides are 3/4×2. what would be the the ends 3/4 x ??

_ \ \
———————

-- I get out in the shop when I can


25 replies so far

View GaryK's profile

GaryK

10262 posts in 2655 days


#1 posted 04-10-2008 10:02 PM

Do you mean that the box narrows from top to bottom at 10 degrees?

Not sure what you are asking. Do you have a drawing?

-- Gary - Never pass up the opportunity to make a mistake look like you planned it that way - Tyler, TX

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Partridge

296 posts in 2623 days


#2 posted 04-10-2008 10:08 PM

no it is a SQ box. just the end tilt

-- I get out in the shop when I can

View motthunter's profile

motthunter

2141 posts in 2466 days


#3 posted 04-10-2008 10:09 PM

from your writing, I am not sure what you mean. Can you do a hand drawing and post it?

-- making sawdust....

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Partridge

296 posts in 2623 days


#4 posted 04-10-2008 10:47 PM

math

i what to now the height of ? before 10deg angle

-- I get out in the shop when I can

View leonmcd's profile

leonmcd

204 posts in 2638 days


#5 posted 04-11-2008 04:58 AM

My guess would be 2.114521888” and the 3/4” face will be slightly larger than 3/4 at 0.769840042”

Is this what you had in mind?

Might want to try this on some MDF just to be sure.

-- Leon -- Houston, TX - " I create all my own designs and it looks like it "

View fredf's profile

fredf

495 posts in 2377 days


#6 posted 04-11-2008 05:29 AM

I am a bit rusty with my trig but I make it out to be 2.163 or not quite 2-21/128

try doing an actual sized drawing and measuring . . .

fred

-- Fred, Springfield, Ma

View swied's profile

swied

74 posts in 2429 days


#7 posted 04-11-2008 06:10 AM

I think we are all struggling to understand your diagram. Here is my guess.

sin(x) = opposite / hypotenuse

In this case x = 80 degrees, the opposite side is 0.75”, and you are seeking the hypotenuse.

You can use Google as your calculator…

http://www.google.com/search?q=0.75%2Fsin%2880+degrees%29&btnG=Search

My answer is 0.761569959”

-- Scott, San Diego

View Partridge's profile

Partridge

296 posts in 2623 days


#8 posted 04-11-2008 08:50 PM

thank you swied,

that got the length of the long angel but i am looking for the length of the 90deg.

all so the wright way of fingering it out.

-- I get out in the shop when I can

View GaryK's profile

GaryK

10262 posts in 2655 days


#9 posted 04-11-2008 09:06 PM

I can’t figure out your drawing either. If you could draw it like a blueprint filling in the numbers you
know I could fill in the blanks.

-- Gary - Never pass up the opportunity to make a mistake look like you planned it that way - Tyler, TX

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Partridge

296 posts in 2623 days


#10 posted 04-11-2008 09:23 PM

how about this if you had a triangle that was 10-90-90 and one of the 90deg lengths was 3/4 what would be the other. you are looking strait on at a board 3/4 thick standing up at 90deg. then you cut the bottom 10deg.

i want to no how much do i have to measure up to get that 10deg angle

-- I get out in the shop when I can

View GaryK's profile

GaryK

10262 posts in 2655 days


#11 posted 04-11-2008 09:31 PM

The hypotenuse (the length of the angled side) for a 90 degree right angle triangle with an angle of 10
degrees and one side 3/4” is 4.3191”.

The length of the 3 sides would be 3/4” x 4.2535×4.3191

-- Gary - Never pass up the opportunity to make a mistake look like you planned it that way - Tyler, TX

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Partridge

296 posts in 2623 days


#12 posted 04-11-2008 09:47 PM

garyk

i do not know how to say this.

-- I get out in the shop when I can

View Peter Oxley's profile

Peter Oxley

1426 posts in 2541 days


#13 posted 04-11-2008 10:24 PM

Okay, you have a box where the vertical sides are 2” high, but one side is tilted 10 degrees. You want to know how tall your angled workpiece should be so that when you cut 10 degrees off of the top and bottom, you are left with a 2” high piece. Correct so far?

AutoCAD says your blank should be 2&5/32” ...
End view 10 degree cuts off top and bottom
The solid black lines are an endview of your workpiece, the dashed red lines are your cut lines.

If you have trig tables or a calculator that does trig, you can do it that way, but I’m just not up to it today!

-- http://www.peteroxley.com -- http://north40studios.etsy.com --

View Partridge's profile

Partridge

296 posts in 2623 days


#14 posted 04-11-2008 10:53 PM

thank you for the pic. peter

iam trying to do it the long way

-- I get out in the shop when I can

View Grumpy's profile

Grumpy

19484 posts in 2518 days


#15 posted 04-12-2008 02:39 AM

Partridge, the answer is 70.9276mm or 2 51/64”by trig calc.

-- Grumpy - "Always look on the bright side of life"- Monty Python

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