# Dumb question about building a pyramid.



## Hanman (Jan 6, 2012)

I have a very simple question that I'm sure most people here will know. I'm honestly a little bit embarrassed to even ask this but I would rather just get a confirmation from some of you before wasting time with trial and error and looking like I don't know what I'm doing in front of my son! My son is to build a Valentine's Day box for school and he wants to make one in the shape of a pyramid and then decorate it. My dumb question is this: When cutting the angles to miter the four sides of our pyramid are they still 45 degrees? Logic tells me it has to be so but for some reason I'm wondering if it would be different. He wants to paint it so I'm just going to use some scrap plywood pieces and sand it down. Correction, I meant to say that HE will sand it down! lol Thanks in advance and feel free to add any jokes you might come up with for me not knowing this simple geometry problem


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## donjohn24 (Oct 15, 2010)

The sides need to be cut at compound angles, and you can get those needed for your particular project here: http://jansson.us/jcompound.html

You can choose a square-based pyramid or one with more sides if you want.

I've not used it myself, but I wish I had found it when I abandoned trying to make a a 'pointy' 8-sided font cover 'cos I couldn't do the math - perhaps with this guide I'll get to it one day!


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## Hanman (Jan 6, 2012)

Wow this is very helpful, thanks for the link! Gonna bookmark it, might come in handy for some other projects as well. Thanks again.


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## DIYaholic (Jan 28, 2011)

Hanman,
That was not a dumb question! The ONLY dumb question is the one you don't ask! That is when mistakes, accidents and even injuries occur. So, KUDOS to you for putting foolish pride aside and asking the question. Actually, could be a good teaching moment for your son!

I do have to say that, I knew it was a compound angle cut. What I am not sure of is the math needed to figure it out. Because you asked the question, I now have a way (link) to figure it out. So, thanks for asking the question. Also, thank you, Don Johnson, for providing the link.

This is excactly what makes LJ's such a GREAT site!


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## DS (Oct 10, 2011)

Cool calculator link. I lost myself in there for a moment.


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## Hanman (Jan 6, 2012)

after looking at the calculator link I realized I hadn't even considered dimensions such as width at the base and height of the pyramid at it's apex. Duh.  One other thing that I didn't see or just may not be understanding is what angle would you cut the bottom of the pyramid so it will set flat on a piece of plywood? Would it be the same angle you use to join the 4 sides together? I could just sand it down pretty easily but it's really bothering me that I can't visualize this! lol Plus it would be really cool if I could get that angle cut properly to miter perfectly with the base so that after a little sanding you wouldn't see any plywood edges.


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## redryder (Nov 28, 2009)

Ya, that's a dumb question. Now how do I save that link to my favorites?


> ?


??


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## MrRon (Jul 9, 2009)

By the way, a true pyramid only has 3 sides, 4 if you count the bottom.


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## North40 (Oct 17, 2007)

Tell that to the Egyptians MrRon!


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## Hanman (Jan 6, 2012)

well we have an imperfect pyramid then. lol Got it assembled, and thanks to Don's link we were successful in our first attempt! Now we're just waiting on some wood filler to dry, then sand and paint. We're gonna post a blog about it when it's finished, which will probably be tomorrow night. The boy is pretty excited to show off his creation.


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## Bill1225 (Oct 31, 2011)

why not dumb it down and mill your stock so you can nest it and cut it like crown moulding


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## Dennisgrosen (Nov 14, 2009)

Beside second DIYaholic 
then you deffently have a big job in front of you since they have calculated 
you wont be able to make a thrue pyramide timely 
and you are about 20000 workmen short ,still need to find the right mountain to cut the blocks out of
anf transport them to location of the building of it 
but never say never 
good luck with the job …... LOL

looks forward to the blog of copying a 1:1 pyramide )))

Dennis


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## Hanman (Jan 6, 2012)

Bill1225 I'm not sure I understand what you mean by nesting it. I'm always looking to learn something though so I'd love to hear your thoughts in more detail.


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## Bill1225 (Oct 31, 2011)

Hanman I'm not the best at explaining things so i went and made one real quick and took a bunch of pictures.Nesting is when u sit the 2 bevels on you miter saw fences and cut it while its standing.


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## Hanman (Jan 6, 2012)

ahhh, I follow ya' now. Thanks for going to that trouble for explaining it to me. I'm better with pictures than words anyways. lol


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## Bill1225 (Oct 31, 2011)

its also an easy way to make a scrap to set your miter gauge to make bigger ones then your miter saw can handle


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## bobsmyuncle (Jan 12, 2011)

>By the way, a true pyramid only has 3 sides, 4 if you count the bottom.

You mean a tetrahedron; that is only one type of a pyramid.

http://en.wikipedia.org/wiki/Pyramid_%28geometry%29


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## BrittanyReviews (Feb 6, 2012)

Wow, that came out great. I want some justfor decoration! Have loved the pyramids ever since I learned their secrets. But thats another for another forum!


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## A3Sneezer (Oct 11, 2013)

Thanks for the web site to calculate angles. Worked great for my , excuse me - my daughters school project.


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## Hinge (Oct 11, 2013)

Bill1225, nice.


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