[Plugin] Stair Maker

[sdmitch]

axys, at present the angular increment for spiral stairs is fixed at 15 degrees. I will need to make that an option. for now, I have attached a spiral stair with 16 steps @ 22.5 degree increment and 800mm wide.

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axys spiral stairs.skp

[axys]

@sdmitch said:

axys, at present the angular increment for spiral stairs is fixed at 15 degrees. I will need to make that an option. for now, I have attached a spiral stair with 16 steps @ 22.5 degree increment and 800mm wide.

Tremendous! Thank you so much. Another useful option would be clockwise or anticlockwise - would it be too much to ask you to make this stair in the opposite direction for me? Thanks again.

[sdmitch]

axys, just copy the spiral stairs using the Move Tool and a tap on the Ctrl key then right click on the copy and choose "Flip Along>Group's Red".

[axys]

@sdmitch said:

axys, just copy the spiral stairs using the Move Tool and a tap on the Ctrl key then right click on the copy and choose "Flip Along>Group's Red".

Got it - thanks again - I'm a rank amateur as you may have deduced ...

[newrui]

Hello sdmitch, just wanted to thank you for such a great plugin! Would you please consider continuous handrails for u-shaped stairs in your next version?

[raineysky]

@newrui said:

Hello sdmitch, just wanted to thank you for such a great plugin! Would you please consider continuous handrails for u-shaped stairs in your next version?

I second that request. Many plugins or native tools can be used for handrails. But I haven't found a way yet to make them look really good without a whole lot of "tweaking". Mine are round handrails. The model I'm working on uses Sdmitch tools heavily. Love 'em. Project Beam is an absolute gift from the heavens, and I hope it gets even better.

[sdmitch]

@newrui said:

Hello sdmitch, just wanted to thank you for such a great plugin! Would you please consider continuous handrails for u-shaped stairs in your next version?

By continuous, do you mean without breaks or that it should be a single entity rather than segments? The rail is added to the stairs as a single entity curve but Sketchup breaks it into segments between the vertical "supports".

I'm assuming you mean the latter since it would only require the addition of one or two edges to make it unbroken. Please clarify.

[Jeggebis]

Hi sd

I tried the plugin and it worked great for creating a simple staircase the first time i tested it out, when i tried to flip it, SU crashed and now i cant get the plugin to create any stairs what so ever, i get this error in the console:

Error: #<ArgumentError: Cannot convert "8.53018372703412" to Length>
/Library/Application Support/Google SketchUp 8/SketchUp/Plugins/Stair Maker.rb:226:in to_l' /Library/Application Support/Google SketchUp 8/SketchUp/Plugins/Stair Maker.rb:226:in get_defaults'
/Library/Application Support/Google SketchUp 8/SketchUp/Plugins/Stair Maker.rb:75:in reset' /Library/Application Support/Google SketchUp 8/SketchUp/Plugins/Stair Maker.rb:66:in initialize'
/Library/Application Support/Google SketchUp 8/SketchUp/Plugins/Stair Maker.rb:22:in new' /Library/Application Support/Google SketchUp 8/SketchUp/Plugins/Stair Maker.rb:22 /Library/Application Support/Google SketchUp 8/SketchUp/Plugins/Stair Maker.rb:226:in call'
/Library/Application Support/Google SketchUp 8/SketchUp/Plugins/Stair Maker.rb:226

Any tips?

[sdmitch]

Stair Maker keeps the default values in a text file with the name of Stair Maker.txt. Some times this file can become corrupted. Find this file, it should be in the plugins folder, and delete it. Stair Maker will recreate it the next time you execute the plugin.

[jeff hammond]

hey sam..

i think the parameters are confusing / not super effective..

generally, when laying out stairs, you'll have a final height which should be one entry..

after that, you basically have a rise/run ratio that needs to be dealt with..
the best way to do this (at least for me) is to have an entry for 'maximum rise'..

in which case i'd enter, say, 8' for the height then maybe 7" as the max rise..
the plugin would then determine that i need 14 steps at ~ 6 7/8" to fill in the space..

having an entry for total height as well as riser height&#of steps is redundant as one fights/determines the other..

does that make sense?

another thing you may consider is not adding the top step.. generally, the top tread is the landing (i.e.- you don't have a tread that butts into the landing at a flush height..)

likewise, it would be nice if there was a checkbox (or something) which gives the user an option to have a railing or not..

……….
all that said, these stairs in particular still wouldn't meet my total requirements so i'm just putting some ideas out there… i'm considering having a custom ruby made which meets my requirements as i imagine it would be far cheaper to do it like that than for me to spend time learning how to make it myself

[TIG]

There already a few free stair making scripts out there...
None of them are perfect either.
Here are a few screen-shots of what can be done, and the options that are useful...

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[sdmitch]

Jeff, I tried to make it so that you could enter any two of three parameters, riser height, number of steps, and stair height. The dominant entry varies with the type of stairs. For "Normal" and "U-Shape", it is stair height. For "Spiral", it is step count. But not being an architect or associated in anyway with the building industry, it is just a wild guess on my part as to what should be the controlling factor.

[jeff hammond]

@sdmitch said:

Jeff, I tried to make it so that you could enter any two of three parameters, riser height, number of steps, and stair height. The dominant entry varies with the type of stairs. For "Normal" and "U-Shape", it is stair height. For "Spiral", it is step count. But not being an architect or associated in anyway with the building industry, it is just a wild guess on my part as to what should be the controlling factor.

right, i see how it's mostly working..
the thing is, the parameter that should be able to vary is the rise per step according to a max rise factor..

ie- the rise is allowed to vary somewhat when building

i can accomplish this with your plugin by setting the height & number of steps but in order to do so, i have to use a (separate) calculator in order to determine the amount of steps.. for instance, say i have a 100" height with max allowable rise of 7.5"..
i have to do 100 / 7.5 = 13.333
so i can then enter 100" in your plugin with number of steps at 14.. (which in turn reports a rise of ~7 1/8")

like i said though.. i'm just throwing this info out there for no reason in particular i'm not sure if other people using the plugin would benefit from it or they like it as is already so don't go changing everything

[jeff hammond]

@tig said:

There already a few free stair making scripts out there...
None of them are perfect either.
Here are a few screen-shots of what can be done, and the options that are useful...

i know.. i think i've tried them all.
i'm thinking that not too many people that build stairs also write in ruby

hence my considering subbing the work out to one of you guys
i'll wait and see if su9 has any dynamic component upgrades and if not, i'm sure i'll be PMing some of you all..

[utiler]

I can't agree more with you re: stair parameters, Jeff!!

To me it seems simple: no matter what type of stair (single run, u-shape, spiral, etc) all start and finish at a know point. That being said floor to floor height is the first input that should be considered. Maximum riser height is the next seeing it is legislated upon. At this point I think it would be handy to see the result of total height / max riser so a fixed riser can be sought.

Where landings are required in single run stairs an input could be entered say 'Landing at Riser No.'

In the case of u-shape stairs, landing location is determined as above only that an additional input needs to be added for the option of the extra top tread at the first stair run which ensures in-situ stairs can be formed efficiently.

[utiler]

Ok, the last post was sent at 2am this morning on my iPad so I didn't have the option to run the plugin....

Sam, I wasn't aware you weren't in the industry so here's a quick glossary of terms which I expect is pretty universal.

I've chosen to make an example of the U-shape in-situ stair as it covers most terms.

My crude attempt at a Dialogue Box

Stair Width: 2600
Stair Height: 3900
Flight 1 Width: 1200
Flight 2 Width: 1200
Tread Depth: 275
Total No. or Risers: 24
Riser Height: 162.5 [I expect this is a system variable that changes as No. of Riser input is changed. This gives the user a visual guide as to their final stair ratio...]
No. risers to Landing: 12 [this locates the landing in the overall flight...]
Rail Height: 900
Rail Offset: 50

[TIG]

This is some UK terminology [alternatives/explanations in brackets[]]

Stair Width [measured from wall to wall or to the string [flight's edge], ignoring handrails]
FL-FL Height [total height through which the stair/flight will rise]
Maximum Riser*** [the statutory maximum height of each step - e.g. 170mm for a public stair in a commercial building, this determines the number of steps in a flight when divided into the FL-FL height and rounded down, the number is also usually min. 2 nr., except at the foot [i.e. the bottom-most step] where one is acceptable]
Minimum Going*** [the statutory minimum tread dimension in plan - e.g. 250mm in a commercial building; note that treads overlap in section, so a 250mm 'going' in plan might be a 280mm flat tread when measured to carpet it]
Nosing [the treads' overlap - say 30mm - the treads overlap in section, so a 250mm plan 'going' might be a 280mm flat tread when measured to carpet it]
***The relationship of Going to Riser is governed by rules too, so you can't use the max/min values to give an unusably steep or shallow pitched stair: e.g. 2R+G>=550mm and 2R+G<=700mm, and the angle of the flight [its 'pitch'] can't exceed 42 degrees too...
Handrail Height [typically 900mm measured from the 'pitch' line drawn through the nosings]
Flight Guarding Height [typically 900mm measured from the 'pitch' line drawn through the nosings - the handrail can guard if it high enough, so with a 750mm high rail [actually disallowed on public stairs where it's min. 900mm anyway!] then additional guarding would be needed up to 900mm if there is no side 'wall']
Landing Guarding Height [typically 1100mm measured from the landing - note that sloping rails can meet this without abrupt changes of direction]
Handrail Diameter [max. 40mm - all but 'fixed' by regs]
Handrail Clearance [min. 60mm]
Thus a handrail can project 100mm into the width of the flight on each side without it being considered restrictive - e.g. for fire-exit widths.
You might need two handrail settings depending on whether or not the side of the flight is against a wall or has an exposed string.
Where two flights pass each other [say with a half-landing] you need to ensure an adequate gap between each flight's handrail and the other flight's string [or its guarding if it is located 'outboard'], this is to avoid 'finger traps' - typically a central 'well' is provided to allow for this 150/250mm wide at the landing.

Other rules include: the 'going' of the [top] landing should be at least the stair's width or 1200mm;
The handrails at the top and bottom of flights must continue 300mm beyond the top/bottom nosing, turning horizontally at 1000m above the landing for their last part [unless forming part of a higher guarding]
It's good practice normally to stagger the nosings of the up/down flights at a landing, as it allows the handrails to works smoothly.
The maximum number of risers in 'public' stairs is limited to 12 nr. limiting the rise per flight to 2040mm.

For 'tapered' treads [like in spiral stairs] there are other complex rules, these vary with usage classes - like...
For flights up to 1000mm wide the going is measured at the centerline of the flight, each going should be a consistent size, the minimum going on the narrow side is say 50mm; the angle of the taper is set at 15 degrees max.; the max/min and 2R+G rules still apply. For wider flights you consider two goings measured 1/3 in from each side, the max/min and 2R+G rules etc apply. Tapered treads running into straight parts of a flight require particular attention to maintain consistency of the treads' going etc...

Staircase design is very complicated.
It needs a lot of customization in all but the simplest of solutions.
I think that the best 'scripted' solution is therefore to give the bare-bones 3d form, perhaps with a line/curve for the rail/guarding so the user can adjust and finish off the stairs...

[rv1974]

There must be ability to set up the net gap between railing posts .

[TIG]

@rv1974 said:

There must be ability to set up the net gap between railing posts .
But that's a 'balustrade' tool not a stair tool ?
The 4"/100mm sphere gap rule will then apply too...

[utiler]

Trust you to try and scare him off the forum all together, TIG!!!

Yes, there are specific max / mins of riser / goings and a 2R+G is the range here in OZ also but for getting a stair modelled effectively and quickly I would have gone down the 'keep it simple' road....