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- Formula?? ( not brakes but mathematics ) Question for the builders!
Draw it to scale?

Posted 4 years agoYou need to know the ‘going’ and the ‘rise’ when building steps

Posted 4 years ago

They are the overall height and the distance to be travelled. Look at building regs for advice. The formula is 2r + g = nlt 550/ nmt 700I’m after curving some decking steps thus…

Your looking at the decking, 4 steps left, 4 on the right. each step/ tread on the left is 250mm deep, each on the right 500mm deep, space in between 4m.

I need a steady curve from 0 to 250mm ( which is the difference between 250 & 500mm ) over a distance of 4 meters. Say at an equal spacing every 400mm.Is there a formula?

Posted 4 years agoI know the rise but thats not important atm. the treads are going level from right to left. If you were to look along the ‘ nose ‘ of the step it would curve outwards from 0mm to 250mm over a distance of 4.0m.

Posted 4 years agoBumping up.

Posted 4 years agoHaze – Member

Draw it to scale?Probably a formula, but drawing is easier – also different types of curve possible.

Edit: drawn in plan obviously

Posted 4 years agoThat’s it. The red curve is the one I’m after. I need to transfer it to the decking though. If I was to devide the 4m up into 10 equal bits how much, going from L to R is each section bigger than the previous?

Posted 4 years agolay it all normally with an overlap – then mark the overlapped decking in situ with the curve you want

cut.

Posted 4 years agoI have to curve the ‘ Rise ‘ which is a length of decking face on. Once I have the rafter ends cut to length to form the curve I can fix the decking riser. Once the ‘ rise ‘ is fixed i will overhang the decking tread and cut to length.

Posted 4 years agoTrail Rat has it in one.

The pro’s preferred method. No fannying about. Quick. Easy.

Posted 4 years agogot a good jigsaw ?

Posted 4 years agoYep, my trusty Festo.

Posted 4 years agoWell, for the puroposes of closure……….some check dimensions to the nearest mm based on a steady curve (radius shown).

Posted 4 years agoThanks mrben. What formula/ program did you use?

I lined up the riser today and clamped it into what I thought was the right position. When measuring I had 310mm and 370mm right.

Just goes to show that you can’t beat the squint of a tradesmans eye.. ðŸ™‚

Posted 4 years agoIt’s a beam camber (assuming you want the curve to be part of a true circle as shown by mrben above) there are a few different ways to lay it out, a compass method and a straight line method – google beam camber calculations (boatbuilding) and you’ll probably find them.

Posted 4 years agotymbian – Member

Thanks mrben. What formula/ program did you use?Just did it in CAD innit (as use it for work), what your seeing is just a screen shot, drawn 1to1 scale and measured the results. I would only be able to figure out a formula having already drawn it.

Posted 4 years ago

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