I want a short circular staircase to make a little dancing area for a dream sequence and I am not understanding the arcs needed. I can’t get them to match without looking weird. I’m sure there’s a very simple solution.
I’m hoping to cut at least one of the tread sets (preferably two in horizontal opposites for either side of the platform) out of one sheet of ply. I was going to figure out the basic math and then add 1” bullnose to one side, but I don’t seem to even be able to get the basic math.
I have the 3x3 platform already, so all I am trying to do is make the treads match and look less… ridiculous.
First thought: The center of the circle should align with the first nosing of the platform, not the center of the platform - like the upper left, not the lower right.
As far as layout goes on a sheet of plywooe, you can turn every other pie shaped tread 180 degrees and they sort of go in a straight line. You might fit a bunch on one sheet.
Here is what I am giving whichever minion chooses the “math” project (Considering the other two projects are “art” I already know which minion will choose this one.) ((edit: called it. Minion two took the “math build” over the “art builds”))
I like giving them just enough to keep their brains moving. As well as choices in how to get to the desired end result.
You have a 4’x8’ sheet.
You take the top right-corner out 3’x3’.
Therefore you have a 48" radius 1/4 circle for the steps.
You have already this drawn at the origin.
Make a group of all of that to avoid messing with the base template.
At this point we know the 1/4 circle circumference is ‘pi’ feet or ~37.7"
If you want the outer size of the wedge shaped step to be say 4 treads -
including the vertically drawn top-step that’s say 5 risers total.
HOWEVER, depending on your area’s exact regs the tapered tread’s going should be be less than ~2" at the narrowest and ~9" at its center***.
The 1/4 circle at the steps’ center is < 48" so 4 treads could be ~ 12" which is just about OK -
for more treads you could go up to 5, BUT the inner 1/4 circle at 12" radius is ~9.4" long and only supports 4 treads ever.
Your 8" outermost tread dim is far too small - around 18" is more logical.
Now draw a line over the group to be the first horizontal nosing to the step.
Use the Rotate tool + Ctrl to radially copy it around the number of times needed.
Select + Edit>Cut, edit the group then Edit>Paste-in-Place…
You haven’t said what the total rise of the steps should be.
A 7.5" per riser seems common for ‘utility stairs’, so the total rise for 5 is 37.5" - is this within your expectations ?
Other considerations - it’s very common to overlap treads a little - by ~1" to form a ‘nosing’.
So the actual ‘cut size’ of the treads needs to be 1" bigger ?
Or make them the size calculated and locate them so they overlap by the 1".
However, the ‘going’ of the tapered tread is measured ‘in plan’ and ignores the nosing -
so at the inner-most end of ~2" is actually nearer ~3" and at the center nearer ~10".
To achieve the min inner going you are limited to 3 steps [~9.4" total], with 4 risers -
however this means that the center going is then well within limits.
In conclusion 3 tapered steps in a 90° swept arc rising x4 == ~30" total, satisfies all of the rules?
You posted the image while I was composing…
Looks OK - probably - but the nosing issue is nor addressed - you can nail/glue a timber 1" lath on the front to achieve this ?
You’ve angled the landing nosing so limited yourself to the fewer risers…
Also the floor plan occupied by the assembly is larger than the 4’x8’ sheet originally shown…
This is very helpful
I was just hoping to be able to get all the treads from one sheet for cost purposes, less from footprint purposes. He ended up cutting the last tread from scrap, so all was well with my budget. (I get 900 dollars per set for the entire thing).
We end up reusing platforms and stairs and… Well everything… So we always build every staircase to an 8" rise for each step, that way we can reuse platforms and legs and stairs like Legos. In fact, everything is built on 8’s. The walls are all divisible by 8, stripes painted are either 8, 4, or 16… Etc. I also only allow one color of “white” and one color of “brown” per season to try and cut down on the need for repainting furniture and railings and floors.
He took this project and disappeared off into stage left. I ended up in a meeting and he had already cut assembled the left half without overhanging the nose portion, so we decided that he could cut the nose pieces separately and it was his responsibility to reattach them whenever the actors scrape them off in a “fit of acting”.
They’re going to get used in the next show for two minutes, and then two weeks after that they will be parked upstage with a wider center platform behind about 8 tables. I’m not too worried about them not looking perfect.
Legend has it if you hover over it for the right amount of time with your tongue in the right place magic marks will appear that will allow you to snap it into position on the correct axis.
Utter balderdash if you ask me.
Just wait 'till your nephew sticks his head between the posts and gets stuck, screaming bloody murder, tearing his ear half off! I guess you will attribute that to Darwin cleaning up the gene pool.
