Working in metric and imperial

[Captain Caveman]

Here's a real life example of fitting some spindles on a staircase.

Diagonal length between posts 2715 mm

Spindles 41 mm

Pitch 42.1 degrees

My workings. I take the tangent of 42.1 and multiply the 41. I use Pythagoras and square that number, I add it to the square of 41, then take the square root of that answer. The spindle cut at 42.1 degrees has an angled length of 55.26 mm.

I take the cosine of 42.1 and multiply it by 2715, that gives me the horizontal run of the staircase, 2014.46 mm.

If I subtract 14 spindles off the horizontal, the gap between the spindles is 96.03 mm. And if I subtract the angle length of the spindles from 2715 mm, my fillets are 129.43 mm long.

Regs means as long as the gap is less than 100mm (approx 4"), then 96.03 mm is good.

So I decided to convert that all to inches.

No chance in hell.

Can you guys show workings out in inches and fractions please? The thing is, if you went to the nearest 1/8 or 1/16 or 1/32 of an inch, 14 and 15 times the error is a big discrepancy.

 

[Auld Phart]

Here's a real life example of fitting some spindles on a staircase.

Diagonal length between posts 2715 mm

Spindles 41 mm

Pitch 42.1 degrees

My workings. I take the tangent of 42.1 and multiply the 41. I use Pythagoras and square that number, I add it to the square of 41, then take the square root of that answer. The spindle cut at 42.1 degrees has an angled length of 55.26 mm.

I take the cosine of 42.1 and multiply it by 2715, that gives me the horizontal run of the staircase, 2014.46 mm.

If I subtract 14 spindles off the horizontal, the gap between the spindles is 96.03 mm. And if I subtract the angle length of the spindles from 2715 mm, my fillets are 129.43 mm long.

Regs means as long as the gap is less than 100mm (approx 4"), then 96.03 mm is good.

So I decided to convert that all to inches.

No chance in hell.

Can you guys show workings out in inches and fractions please? The thing is, if you went to the nearest 1/8 or 1/16 or 1/32 of an inch, 14 and 15 times the error is a big discrepancy.

NOPE


I'm retired.

I don't do any work anymore.

 

[White 6]

Here's a real life example of fitting some spindles on a staircase.

Diagonal length between posts 2715 mm

Spindles 41 mm

Pitch 42.1 degrees

My workings. I take the tangent of 42.1 and multiply the 41. I use Pythagoras and square that number, I add it to the square of 41, then take the square root of that answer. The spindle cut at 42.1 degrees has an angled length of 55.26 mm.

I take the cosine of 42.1 and multiply it by 2715, that gives me the horizontal run of the staircase, 2014.46 mm.

If I subtract 14 spindles off the horizontal, the gap between the spindles is 96.03 mm. And if I subtract the angle length of the spindles from 2715 mm, my fillets are 129.43 mm long.

Regs means as long as the gap is less than 100mm (approx 4"), then 96.03 mm is good.

So I decided to convert that all to inches.

No chance in hell.

Can you guys show workings out in inches and fractions please? The thing is, if you went to the nearest 1/8 or 1/16 or 1/32 of an inch, 14 and 15 times the error is a big discrepancy.

I assume you are talking about a post to post system, with the hand height the same as a level run, or you would have hired somebody for an over-the-post system install. Her is the LJ Smith Balustrade installation guide. Be advised, if using the correct Newels, you can do the installation with a chalk line, if all bausters are equal spade. This holds true for pin top balusters on non-plowed rail, as well as square head balusters, for going in plowed rail with fillet.

https://static1.squarespace.com/static/60eb48a70423516ca6e90cce/t/60ebbb9ef229ba2ea853c88a/1626061733004/Balustrade+Installation+Guide+%28English%29.pdf

 

[DGS49]

If you are not comfortable with 1/4" and such, we have these things called, "decimals." 3-1/4" is the same as 3.25 inches. Works out fine.

 

[Captain Caveman]

I assume you are talking about a post to post system, with the hand height the same as a level run, or you would have hired somebody for an over-the-post system install. Her is the LJ Smith Balustrade installation guide. Be advised, if using the correct Newels, you can do the installation with a chalk line, if all bausters are equal spade. This holds true for pin top balusters on non-plowed rail, as well as square head balusters, for going in plowed rail with fillet.

https://static1.squarespace.com/static/60eb48a70423516ca6e90cce/t/60ebbb9ef229ba2ea853c88a/1626061733004/Balustrade+Installation+Guide+%28English%29.pdf

It's an existing staircase. When the house was built, it was the imperial measurement days, but things don't seem to equate to easy inches and fractions.

Maybe I'm being too mathematical, they probably just used bevel mitres etc.. as opposed to calculating things on paper.

I know that the max angle of a staircase is 42 degrees, so even my digital spirit level is getting a bit too exact.

 

[Winco]

Easy Math.
But don't PM Me, I don't know shit.

 

[luiza]

Here's a real life example of fitting some spindles on a staircase.

Diagonal length between posts 2715 mm

Spindles 41 mm

Pitch 42.1 degrees

My workings. I take the tangent of 42.1 and multiply the 41. I use Pythagoras and square that number, I add it to the square of 41, then take the square root of that answer. The spindle cut at 42.1 degrees has an angled length of 55.26 mm.

I take the cosine of 42.1 and multiply it by 2715, that gives me the horizontal run of the staircase, 2014.46 mm.

If I subtract 14 spindles off the horizontal, the gap between the spindles is 96.03 mm. And if I subtract the angle length of the spindles from 2715 mm, my fillets are 129.43 mm long.

Regs means as long as the gap is less than 100mm (approx 4"), then 96.03 mm is good.

So I decided to convert that all to inches.

No chance in hell.

Can you guys show workings out in inches and fractions please? The thing is, if you went to the nearest 1/8 or 1/16 or 1/32 of an inch, 14 and 15 times the error is a big discrepancy.

One of the most important ways of becoming a genius is learning how to successfully delegate and how to avoid blame when things get blown off course .

 

[Zebra]

what is not decimal ….


24 hours

7 days


12 months

 

[The Duke]

It's an existing staircase. When the house was built, it was the imperial measurement days, but things don't seem to equate to easy inches and fractions.

Maybe I'm being too mathematical, they probably just used bevel mitres etc.. as opposed to calculating things on paper.

I know that the max angle of a staircase is 42 degrees, so even my digital spirit level is getting a bit too exact.

Maybe not to you, but I got a tape measure and know how to read it.

 

[Captain Caveman]

Maybe not to you, but I got a tape measure and know how to read it.

Read it then and give me the figures

 

[White 6]

It's an existing staircase. When the house was built, it was the imperial measurement days, but things don't seem to equate to easy inches and fractions.

Maybe I'm being too mathematical, they probably just used bevel mitres etc.. as opposed to calculating things on paper.

I know that the max angle of a staircase is 42 degrees, so even my digital spirit level is getting a bit too exact.

Post to post rail or over the post? Plowed or unplowed rail? Don't overthink it. I have seen and worked with very good stair people, that could pass a geometry test on their best day, that built excellent stair systems, within their capabilities.

 

[Captain Caveman]

Post to post rail or over the post? Plowed or unplowed rail? Don't overthink it. I have seen and worked with very good stair people, that could pass a geometry test on their best day, that built excellent stair systems, within their capabilities.

Well. I did the job today. The existing base rail was 5 mm too long. Both newal posts are out of plumb in both planes (8 mm left to right and 7 mm front to back and out of wind), the existing top handrail bracket was fitted upside down, hence why it shows and needs a small wooden cap below it to hide it. I can't redrill the newal post and fit the bracket correctly because of the butchered holes in it. And the customer and I decided to add an extra spindle. The handrail was 20 mm longer than the base rail, so I pulled the two newal posts in with straps so both base rail and hand rail are now the same length.

The problem is, when I do a job, everything has to be done exact to the fraction of a millimetre. The original staircase is not (in my book) within tolerance, the carpenter was obviously on the beer. The guy that did the base rail, hand rail, and incorrect spindle spacing was equally drunk, if not worse.

It'll have been, I guess, originally built to imperial measurements, but fitted to beer tolerance. I would have followed suit in imperial if it worked out as such.

So it's done, bill will be handed over tomorrow.

 

[White 6]

Well. I did the job today. The existing base rail was 5 mm too long. Both newal posts are out of plumb in both planes (8 mm left to right and 7 mm front to back and out of wind), the existing top handrail bracket was fitted upside down, hence why it shows and needs a small wooden cap below it to hide it. I can't redrill the newal post and fit the bracket correctly because of the butchered holes in it. And the customer and I decided to add an extra spindle. The handrail was 20 mm longer than the base rail, so I pulled the two newal posts in with straps so both base rail and hand rail are now the same length.

The problem is, when I do a job, everything has to be done exact to the fraction of a millimetre. The original staircase is not (in my book) within tolerance, the carpenter was obviously on the beer. The guy that did the base rail, hand rail, and incorrect spindle spacing was equally drunk, if not worse.

It'll have been, I guess, originally built to imperial measurements, but fitted to beer tolerance. I would have followed suit in imperial if it worked out as such.

So it's done, bill will be handed over tomorrow.

Re-work of finished carpentry is always a pain in the ass, as having to work around or cosmetically cover original mistakes. I take it, replacing original newel(s) was not an option for one reason or another.

Is the customer happy? I wouldn't mind seeing a pic, unless you are so unhappy with finished effect, you would rather not be associated.

 

[Captain Caveman]

Re-work of finished carpentry is always a pain in the ass, as having to work around or cosmetically cover original mistakes. I take it, replacing original newel(s) was not an option for one reason or another.

Is the customer happy? I wouldn't mind seeing a pic, unless you are so unhappy with finished effect, you would rather not be associated.

Only took a couple of photos, normally I don't bother -





The top newal was out of plumb, the half newal was also out of plumb and twisted. The bottom was 88 degrees and the top 86 degrees. Theoretically, the handrail at the top should match the dimensions of the base rail, but it was nearly half an inch difference. Just means the lobe spindle is not plumb.

The customer is over the moon, so I have to be as well despite knowing everything is not accurate!

 

[White 6]

Only took a couple of photos, normally I don't bother -

View attachment 946916

View attachment 946917

The top newal was out of plumb, the half newal was also out of plumb and twisted. The bottom was 88 degrees and the top 86 degrees. Theoretically, the handrail at the top should match the dimensions of the base rail, but it was nearly half an inch difference. Just means the lobe spindle is not plumb.

The customer is over the moon, so I have to be as well despite knowing everything is not accurate!

Nice job on the Knee wall stair. I think I would have used an oval rose on the newel post to cover existing holes or at least suggested to the owner.

 

[Captain Caveman]

Nice job on the Knee wall stair. I think I would have used an oval rose on the newel post to cover existing holes or at least suggested to the owner.

The bannister rail was fitted to the upside bracket that was bent against it's hinge, so I drilled a counter sunk hole and whammed a screw in to stiffen it up. After the photo, I filled the drill hole with glued in wood and sanded it.

The decorator is there today and tomorrow to do the hall, landing, and stairs. So it'll just be white satin wood off.

 

[Captain Caveman]

White 6

I believe staircases in the US are different to the UK. Yours are like saw teeth with the risers and threads nailed on, then newal posts and stringers fitted.

Our stringers are usually routered to take the risers and threads. Then the newal posts and stringer(s) are morticed, tenoned and shaped etc.. The staircase is then fitted as a oner. The bottom of the landing newal often sticks down below ceiling height in the room below. So replacing them is kinda tricky.

I think we can cut the newal off about 6 to 8 inches above carpet height and the new post has a dowel shaped end. So you drill a vertical hole in the old newal stump part and glue in the new newal with the dowel part.

 

[alang1216]

Here's a real life example of fitting some spindles on a staircase.

Diagonal length between posts 2715 mm

Spindles 41 mm

Pitch 42.1 degrees

My workings. I take the tangent of 42.1 and multiply the 41. I use Pythagoras and square that number, I add it to the square of 41, then take the square root of that answer. The spindle cut at 42.1 degrees has an angled length of 55.26 mm.

I take the cosine of 42.1 and multiply it by 2715, that gives me the horizontal run of the staircase, 2014.46 mm.

If I subtract 14 spindles off the horizontal, the gap between the spindles is 96.03 mm. And if I subtract the angle length of the spindles from 2715 mm, my fillets are 129.43 mm long.

Regs means as long as the gap is less than 100mm (approx 4"), then 96.03 mm is good.

So I decided to convert that all to inches.

No chance in hell.

Can you guys show workings out in inches and fractions please? The thing is, if you went to the nearest 1/8 or 1/16 or 1/32 of an inch, 14 and 15 times the error is a big discrepancy.

Don't feel too bad, the engineers who built Hubble got confused and a space flight was required to fix it.

 

[White 6]

White 6

I believe staircases in the US are different to the UK. Yours are like saw teeth with the risers and threads nailed on, then newal posts and stringers fitted.

Our stringers are usually routered to take the risers and threads. Then the newal posts and stringer(s) are morticed, tenoned and shaped etc.. The staircase is then fitted as a oner. The bottom of the landing newal often sticks down below ceiling height in the room below. So replacing them is kinda tricky.

I think we can cut the newal off about 6 to 8 inches above carpet height and the new post has a dowel shaped end. So you drill a vertical hole in the old newal stump part and glue in the new newal with the dowel part.

View attachment 947913

They probably are very different. I am kind of old school, not ascribing more fad mountings of newels on newel plates, sitting on top of treads or landings. All newels should be mortised and locked in the supporting substructure. I shake my head, when walking through what is supposed to be show home and can feel a wiggle on the newel at that starting tread or going across balconies, figuring, somebody likes shortcuts and somebody else has too close a relationship with the building inspector. I am no fan of false treads and risers, preferring full treads and risers, even on carpeted stairs. Use of those things only reflects saving money on parts, while spending more on installation to assemble parts, not structural, but meant to cover structure to fool the eye. I was trained by Jack Breed of Breed sales, one of the earliest reps for LJ Smith Stair Systems. He noted, "when the little pot-bellied ten-year-old comes flying down the stairs full speed, grabs that newel and swings around the corner, he shouldn't end up in the floor with the bottom half of the balustrade lying beside him." A well-built stairway becomes the focal point of the home. It is the only millwork assembly, required to be structural, not simply trim for eye appeal, and is the pinnacle of the finished carpentry trade. Back in the day, the wholesaler, I worked for carried the largest selection of stair parts in 6 states, and as an outside sales rep and then buyer, was intimately familiar with just about all facets, but have not been associated with the trade in 20+ years.