LumberJocks

how to calculate?

  • Advertise with us

« back to Joinery forum

Forum topic by kennyjoy posted 12-30-2017 10:03 PM 562 views 1 time favorited 14 replies Add to Favorites Watch
View kennyjoy's profile

kennyjoy

4 posts in 57 days


12-30-2017 10:03 PM

Topic tags/keywords: question tip

How to calculate the above angle? Thanks!


14 replies so far

View Luthierman's profile

Luthierman

203 posts in 995 days


#1 posted 12-30-2017 10:18 PM

I think we need a little more info.

-- Jesse, West Lafayette, Indiana

View John Smith's profile

John Smith

455 posts in 71 days


#2 posted 12-30-2017 10:23 PM

are those table legs ??
I am terrible with math, geometry, algebra and anything else that contains numbers.

I just get me some cardboard and make templates – then cut from the pattern (when possible).

I just bought a new angle finder at Lowe’s, and if I read it correctly,
the outside line is 103 degrees and the inside line is 113 degrees and the joint line is 62 degrees.
if your drawing is drawn to scale, you could try those numbers on a template and see if the work for you.

.

.

View Luthierman's profile

Luthierman

203 posts in 995 days


#3 posted 12-30-2017 10:45 PM

Am I missing something? There is no picture, nothing. Weird.

All I see is a post asking this question with zero reference to anything.

-- Jesse, West Lafayette, Indiana

View John Smith's profile

John Smith

455 posts in 71 days


#4 posted 12-30-2017 10:50 PM

I guess my 10 year old laptop is Blessed – I see a simple hand drawing.

View ChuckV's profile

ChuckV

3096 posts in 3435 days


#5 posted 12-30-2017 10:58 PM



Am I missing something? There is no picture, nothing. Weird.

All I see is a post asking this question with zero reference to anything.

- Luthierman

As Sgt. Schultz would say, “I see nothing!”

-- “Big man, pig man, ha ha, charade you are.” ― R. Waters

View John Smith's profile

John Smith

455 posts in 71 days


#6 posted 12-30-2017 11:07 PM

this is Kenny’s drawing.

.

View MrUnix's profile

MrUnix

6368 posts in 2107 days


#7 posted 12-30-2017 11:31 PM

It’s a WebP image – a relatively new Google kitchen sink image format they are trying to push on the Internet that isn’t widely supported. Chrome and Opera will (should) display them, but not many others.

Cheers,
Brad

-- Brad in FL - In Dog I trust... everything else is questionable

View pontic's profile

pontic

558 posts in 516 days


#8 posted 12-31-2017 12:41 AM

I look at it this way; The circumsribed angle is 113. You want to cut a miter so it will make a table leg giving a flat surface. This means that you must adjust the miter so that 90 is to 45 as 113 is to X.
solving for x you get 90-45 =45 as 113-X=45 or 68 degrees

-- Illigitimii non carburundum sum

View jerryminer's profile

jerryminer

890 posts in 1349 days


#9 posted 12-31-2017 01:24 AM

It’s not clear exactly what angle you are trying to calculate.

Trigonometry is the mathematical way to calculate angles from known lengths. In your case, there is not enough information to give a “calculated” angle.

Measuring with a protractor is a way to derive angles from a drawing or object.

I often let SketchUp do my calculating for me. In the case of the drawing you posted, I imported that into SketchUp and got these results:

-- Jerry, making sawdust professionally since 1976

View John Smith's profile

John Smith

455 posts in 71 days


#10 posted 12-31-2017 01:30 AM

you lost me at “then you adjust the miter”.

that is why I make cardboard templates and cut from patterns.

.

View jerryminer's profile

jerryminer

890 posts in 1349 days


#11 posted 12-31-2017 01:41 AM

If you are trying to miter two pieces of the same dimension (at the miter), then—as I see your drawing, (which I have cleaned up a little below)—you want to be about 12 degrees off of square, or 102 degrees (90 + 12). The miter angle for each piece would then be 51 degrees.

In order to cut a 51 degree miter, you would set your miter saw or tilt your table saw to 39 degrees (because miter gauges read 90 degrees off from their actual angles—-don’t ask me why).

If you are trying to miter pieces of different dimensions, than the angles will change and will depend upon the dimensions of the pieces.

-- Jerry, making sawdust professionally since 1976

View tomsteve's profile

tomsteve

754 posts in 1127 days


#12 posted 01-01-2018 02:55 PM



are those table legs ??
I am terrible with math, geometry, algebra and anything else that contains numbers.

I just get me some cardboard and make templates – then cut from the pattern (when possible).

- John Smith

keepin it simple sure takes out the complicated stuff and makes it,welp, simple!
i might be mistaken, but with the 62 degrees at the joint, i think the bottom cut on the leg( if its a leg) should be 28 degrees?

View ArtMann's profile

ArtMann

837 posts in 724 days


#13 posted 01-01-2018 03:17 PM

The image has no dimensions so you can’t calculate anything. If I were you, I would make a 1:1 model out of cardboard and then measure the angles and dimensions you want.

View pontic's profile

pontic

558 posts in 516 days


#14 posted 01-01-2018 03:28 PM



you lost me at “then you adjust the miter”.

that is why I make cardboard templates and cut from patterns.

.

- John Smith

I’m with you make it out of card board first.

-- Illigitimii non carburundum sum

Have your say...

You must be signed in to reply.

DISCLAIMER: Any posts on LJ are posted by individuals acting in their own right and do not necessarily reflect the views of LJ. LJ will not be held liable for the actions of any user.

Latest Projects | Latest Blog Entries | Latest Forum Topics

HomeRefurbers.com