How to add quadrant to this stringer?

[redhexagonal]

I have a winder staircase that has a section of stringer that has three cuts that form a sort of curve. The corners of the cuts have been rounded a bit too. I’d like to add a quadrant to the top of the stringer - I was going to use a rip cut of a bullnose mdf architrave here because the stringer is a bit too wide on this wall to use a quadrant. I’m not sure whether to try and cut three pieces to fit these cuts, or try and bend a piece of the mdf and fill the gaps between it and the stringer somehow. What do you reckon?

 

[redhexagonal]

Any ideas about how to do this?

 

[johnny2007]

Wrap the quadrant in a cloth, wet it and bend it to your requirement.
Leave it until dry (1 or 2 days) and you'll have a nice curve that you can pin or glue.
The corners need to be mitre cut, so you'll need to calculate the angle.

 

[redhexagonal]

Wrap the quadrant in a cloth, wet it and bend it to your requirement.
Leave it until dry (1 or 2 days) and you'll have a nice curve that you can pin or glue.
The corners need to be mitre cut, so you'll need to calculate the angle.

I’m using a rip of mdf not sure wetting it is a good idea

 

[johnny2007]

Use wood

 

[redhexagonal]

Use wood

I was going to use a rip cut of a bullnose architrave because the stringer is about 30mm wide on that section. The rest is 18mm. Maybe I can bend another bit of wood next a wood quandrant.

If I bend wood(or mdf) to fit this section, there will be gaps between the quadrant and the stringer because the stringer isn’t actually curved , its 3 sections that have been sanded a bit. Should I sand the stringer hard into a curve or can I fill the gap with wood filler or something? And nail it where they touch?

 

[opps]

If you want to eliminate the rounded edges, why not use two pack filler to straighten them up?

 

[opps]

Wrap the quadrant in a cloth, wet it and bend it to your requirement.
Leave it until dry (1 or 2 days) and you'll have a nice curve that you can pin or glue.
The corners need to be mitre cut, so you'll need to calculate the angle.

Can you bend quadrant in the same way that you can bend a wood pole? Wouldn't the timber twist as it is bent?

 

[redhexagonal]

If you want to eliminate the rounded edges, why not use two pack filler to straighten them up?

That would mean three straight sections and lots of mitres. I was thinking a curve might look better. Im not sure what will look best tbh which is why I’m asking!

 

[opps]

I was going to use a rip cut of a bullnose architrave because the stringer is about 30mm wide on that section. The rest is 18mm. Maybe I can bend another bit of wood next a wood quandrant.

If I bend wood(or mdf) to fit this section, there will be gaps between the quadrant and the stringer because the stringer isn’t actually curved , its 3 sections that have been sanded a bit. Should I sand the stringer hard into a curve or can I fill the gap with wood filler or something? And nail it where they touch?

I think you need to rethink your choice of moulding given the 18mm Vs 30mm. IMO, there is no way you can make quadrant look consistent, I may be wrong though.

Hopefully @JobAndKnock will be able to give you the benefit of his extensive knowledge.

 

[redhexagonal]

I think you need to rethink your choice of moulding given the 18mm Vs 30mm. IMO, there is no way you can make quadrant look consistent, I may be wrong though.

Hopefully @JobAndKnock will be able to give you the benefit of his extensive knowledge.

There are actually two curved sections (its a double winder staircase) , one is 25mm wide and one is 38mm. The rest of the stringer is all 18mm

 

[opps]

That would mean three straight sections and lots of mitres. I was thinking a curve might look better. Im not sure what will look best tbh which is why I’m asking!

On reflection, I am not sure that understood your original question. I had assumed that you meant that the edge of the timber had become rounded over time and that you were planning to fit the moulding to hide it.

 

[redhexagonal]

On reflection, I am not sure that understood your original question. I had assumed that you meant that the edge of the timber had become rounded over time and that you were planning to fit the moulding to hide it.

No, I’m putting a quadrant on the square edged stringer, to smarten it up and hide any cracks and on the wider bit to hide a 20mm wide section of easifill/foam

 

[opps]

There are actually two curved sections (its a double winder staircase) , one is 25mm wide and one is 38mm. The rest of the stringer is all 18mm

Jobandknock is the forum member that I think is best suited to advising you. Hopefully he will be along soon.

 

[opps]

No, I’m putting a quadrant on the square edged stringer, to smarten it up and hide any cracks and on the wider bit to hide a 20mm wide section of easifill/foam

Going slightly off topic. The house that I am currently working in has a plaster ogee type moulding running along the top of the strings. They had a 5mm tall crack where they meet the 120yr old strings. I noticed that there was some bounce (in and out of the wall, rather than up and down) in the strings, so I drilled a series of small holes through the strings and squirted in expanding foam to eliminate the bounce (and did so until the foam filled the crack).

I find it works incredibly well. I don't like drilling through strings and in to the wall (with screws and plugs) unless I know that there are no pipes or cables.

I am a decorator, I seldom use Easifill. In your original scenario, I too would have used foam but I would then have used one of the lightweight fillers such as Toupret RedLite or Red Devil One Time. Powder based filler tend to "blow" over time when in contact with timber.