Math help

[ScottM]

50+ years ago I wish I paid more attention to my geometry teacher then the girl that sat next to me. TBT she never gave me the time of day but I still remember her name, Martha. Anyway I was given a piece of 3/4" cedar to make a burial urn. The wood is 9 1/2 wide and 3/4" thick. I think if I cut the pieces on a 45 the inside dimensions will be at least 7 1/2". Am I right? I have nothing to spare on a test cut so I have one shot at it.

 

[FredP]

8"

 

[tvrgeek]

But you do have a piece of paper.

 

[Bill Clemmons]

Is it 9 1/2" wide (across the grain) or long (with the grain)? If it is 9 1/2" long by 3/4" thick, then a 45* miter on each end will leave 8" long on the inside, as Fred said.

 

[Phil S]

Fred is correct At 45 degrees the amount you cutoff will equal to the thickness of the wood.
In case you want to know the length of the cut measured along the miter will be the thickness times the square root of 2, approx 1.41

 

[ScottM]

Thanks Fred. That is what I thought it was but every time I tried to think it out I came out with brown hair and hazel eyes. TBT the scary part is most nights I could not tell you what I have for dinner the night before.

 

[pop-pop]

Of all the math courses that I took through Differential Equations, by far the one that I use the most is good old Plane Geometry from High School.

 

[ScottM]

But you do have a piece of paper.

Yes I do but I learned a long time ago that when you are not sure go to people you are sure you trust have the right answers.

 

[smallboat]

Ah… Martha. Tom Waites wrote a song to her.

 

[Dee2]

8" assuming no saw kerf.

 

[Fishbucket]

8" assuming no saw kerf.

The saw kerf will be on/ in the boards edge.

 

[Gotcha6]

If you're planing on mitering across the grain, you could gain a little distance by flipping the board over after the first one is cut and using the backside of the second cut as the front of the second piece, etc. This may give you the opportunity to make the box LONGER, but it won't help with the width dimension. Will you be mitering all sides?

 

[ScottM]

If you're planing on mitering across the grain, you could gain a little distance by flipping the board over after the first one is cut and using the backside of the second cut as the front of the second piece, etc. This may give you the opportunity to make the box LONGER, but it won't help with the width dimension. Will you be mitering all sides?

Yes all 4 sides.

 

[Gotcha6]

Yes all 4 sides.

4 sides, or 6?

 

[Skymaster]

lock miters

 

[ScottM]

4 sides, or 6?

4

 

[danmart77]

Ah… Martha. Tom Waites wrote a song to her.

Tom' s best album by far.

 

[ScottM]

Thanks everyone for your help and advise. I knew where to find the experts. I think I had a piece of wood left over that measured 9 1/2 x 10. I still have some finishing work and personalization do. I will post pictures then.