I am trying to build a spiral staircase with gaps in the treads with a solid handrail. I can create a spiral staircase with solid treads and handrail, but unsure how to create something like the staircase attached? Ignore the irregular handrail in sections. Any assistance would be greatly appreciated. Thank you in advance! 
SPIRAL STAIRS.skp (885.4 KB)
It loos like you’ve got what you are requesting. Is there something different that you want?
Hi @DaveR,
Thank you for your reply. Yes, this is a SU example, however I am unsure on how to re-create this as that model wasn’t done by me. Creating gaps in the treads with a solid handrail is where I am unsure? Hope that makes sense?
If I were going to model something like this I would probably start with the Curve Maker extension to drag a helix and then use Upright extruder to extrude the raills/walls.
The treads I would make as components instead of groups and use a Copy/Rotate thing to make the copies at the desired interval.
1 Like
Thank you @DaveR for the explanation. Is there a way to create this with native tools and not extensions?
Yes. It can be done with native tools but it’s more work.
Apologies I wasn’t clear from the beginning, I need to build this using only native tools as students aren’t using extensions in SketchUp.
You could do it the same way we worked it out in your earlier thread on spiral stairs, but cut out the space where the ‘gap’ needs to be.
Thank you @Box. I’ll try that and see how I go
@Box I can’t create a gap using push/pull as the tread is angled. Any other suggestions? Thank you.
If you use components to create the repeating geometry it is quite simple to construct what you need. Here I have done a very basic version, from these couple of components you can modify it as you want and create a slopped handrail and a flat bottom or slopes on both ends etc. This also allows you to make an incredibly detailed set of stairs by only making the details once.
Because it is all solid components it can easily be made into a single solid and smoothed or parts like the treads kept as individuals. No extensions or anything fancy needed. If you want it smoother or more stairs per circle increase or decrease the number of segments used.
The component I start with is just a wedge from a 24 seg circle, divided into two components. One for the tread and one for the handrail and then nested into another for ease of copy/moving.
1 Like
@Box thank you so much for taking the time to explain and demonstrate. I truly apreciate it
@Box I followed your instructions and it all worked great, however I don’t know how to get the inner solid handrail to look smooth without it looking distorted? I tried the Outerbox and smooth edges, but it doesn’t look smooth. There is no problem with the outer handrail. I’ve attached the model if you don’t mind taking a look? Thank you so much!
Spiral open treads.skp (241.8 KB)
You need to go back to the point where you have separate components. The inner one needs to be a smooth slope like the outer one. Since you have used 48 segments for 16 stairs you have 3 segments per curve. To make them slope properly the easiest way is to weld the long edges, then pull down one short edge. This should give you a smooth looking slope, albiet triangulated.
For example.
You’ll get a smoother result if you draw in and smooth the top segments before welding, but that may be more confusing to explain.
1 Like
@Box thank you so much. Your generosity in offering your time to demonstrate and explain is amazing!! Many many thanks. I’ve got it working now. You are an absolute legend!!
1 Like