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A cut string stair in oak, blow by blow.

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MikeG.

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Right, let's start at the beginning. I have a temporary staircase made of bits of construction pine, open tread, totally non-compliant with regulations, and we've put up with it for long enough. So I bought some oak. This stair will be the first and probably the last that I have ever made, and I wanted to make it individual but still traditional, so I settled on a cut string stair. Better get on with it......

I haven't any photos of running the waney edge boards through a friends big planer thicknesser, because that's just dull. Two boards that I couldn't take with me, though, were the strings, because of their length and the position of his machine. So I had to clean those up by hand:



I used an electric hand held plane as a scrub plane, then followed up with a belt sander across the grain, then along the grain, then a number 6 hand-plane to flatten, then a belt sander to finish. It was hard work to clean up the two strings, but on each of them I only had to get to a finish on one side, and just flatten the other side to something like:



Proper joiners would no doubt make the strings first, but I was a bit nervous of cutting into these massive timbers, especially as I wasn't clear how to reference the cut-string side and the straight string side.....so I did a production run of ballusters:





..........and ground to a halt. 25mm was too skinny. So I raided my stores and came up with a whole heap of assorted bits:



Thank goodness for a bandsaw and a planer thicknesser:



Thirty mm square was a whole lot better. I sanded them in pairs:



I wanted to have stopped chamfers, but I think I worked out this was over 300 stops, and I really didn't want to do those all by hand. I hate chamfers which stop in a burnt half-round feathery mess, and eventually, with a little help, came up with a plan involving a bearing-guided straight cutter and a jig or 3.

















On the end of each of the stair ballusters (which are two different lengths) is a dovetail. For those used to me hand-doing most stuff, sorry:







However, I did shape the dovetails by hand:







I also cut out the treads:



With a cut string, the end of the tread projects out past the string, but you don't see the end grain (normally). You mitre in a piece, which performs the job of trapping the ballusters in their dovetail mortice. Another job for the guided cutter and a pattern:



This time the guide was on the top:



There was also the bullnose step at the bottom to deal with:



 

Nelsun

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Thanks Mike. Looking forward to the rest of the build. Is this your first set of [making] stairs? From other folk I've seen either restoring or building anew, it's something easy to get lost down some dark rabbit holes with. Would love to build one some day... in theory at least.
 

Steve Maskery

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That is absolutely the right way to mould the ballusters. Many people (such as the bloke who made my SIL's very expensive oak staircase) would have just routed with a 45 degree cutter, so that one face has a straight lead out and the adjacent face has a curved one. He also dealt with the @two different length problem by buying in a load of ready-made ballusters and sticking and extra bit on the end, end-grain-to-end-grain. Not even making the joint at a cove or bead. It looks awful. Listed building. But she was married at the time to a bloke on 300K p.a. More money than taste, that's the phrase that comes to mind.
Glad you are showing how to do it properly.

Of course, I am shocked that you didn't do it with nothing more than a shave horse and a spokeshave. Standards are slipping, Mike, standards are slipping... :)
 

MikeG.

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Steve Maskery":9jpmgbgw said:
......... I am shocked that you didn't do it with nothing more than a shave horse and a spokeshave. Standards are slipping, Mike, standards are slipping... :)
:lol: :lol:
 

MikeG.

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Back to ballusters. Here's the pile of dovetailed ballusters, for the stairs only. It's a different detail on the landing:



Having made the tenon, time for the mortice. The location of these is absolutely critical. With a straight string you just space the ballusters out along the string, taking no account of the step position. With a cut string stair the ballusters actually sit on the tread, and need to be in the same place on each one, and evenly space up the stair. So I worked it out carefully in CAD, then made a router jig:



The straight sided mortise was adjusted to a dovetail, using a chisel another little pattern piece in ply:











Now.........deep breath........time to tackle the strings. Firstly, do a careful drawing, and make a jig. This one just for marking out. After much thought I decided to start with the cut string:







I used a jig because I don't have the little round screw-on thingies that pros use on a roofer's square (or similar). The jig simply had the rise along one side and the going along the other, with a right angle between.



I also had check dimensions so that I could see if there were any accumulated errors. I checked a few times before I picked up a saw:





Now, it's important to understand that one string (the cut string) uses the underside of the tread and the back of the riser as a reference, and the other side (the straight string, against the wall) uses the top/ outside. I haven't the first idea how they set out the two different sides in relation to each other, when other than the floor and top newel lines there isn't a single point of reference relating one to the other. I made up another little jig:



I placed the cut string on top of the straight string, marked off the reference points top and bottom, and then used the little jig to transfer the step and riser locations across:





I raided the scrap bin for another jig, this time to make a template for routing out the housings for the tread and riser. Lots of careful measurement ensued (the sliver of cereal packet cardboard represents a wedge):









Again, I worked out how far apart each jig station was, and marked that down the string. I did a trial cut on the back of the string:





As you can see from the trial fit, I needed to adjust a tiny bit, so I added a few layers of tape:



This was the first go in earnest:



Disaster! Running around the corner on the underside of the nosing (overhang), I assumed that a square corner on the jig would produce a square corner in the cut.....but it didn't. It rounded it. So I had a little think:





I now could make the cuts in two different phases, and so never actually run the router around the corner.

I found it easier to work on the tall horses:



I don't seem to have a photo of the finished straight string. More tomorrow.
 

Trevanion

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That is the only downside with stair trenching jigs, they leave a little radius on the riser/tread junction which can be unsightly but more often than not nobody notices. You discovered the workaround anyway!
 

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Steve Maskery":5prxdc65 said:
Of course, I am shocked that you didn't do it with nothing more than a shave horse and a spokeshave. Standards are slipping, Mike, standards are slipping... :)
There is photographic proof on another thread that Mr Maskery not only owns a chisel, but has used it in anger, with a mallet! And a hand saw !The universe is turning inside out. It feels like a Doctor Who episode, where alternate realities are on collision course. It's not going to end well.

Perhaps there is a simpler explanation. MikeG and Steve Maskery have swapped bodies. It's all starting to make sense now...
 

MikeG.

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Here's a couple of photos I missed from the process yesterday, which prove I am not Steve Maskery. :lol: The strings need a dead straight edge for setting out the geometry of the stairs. There's no way I can handle 12' by 1' by 2" boards through a planer alone, so I sat them one at a time on the horses and did it with a hand plane. Once I got close to straight I used my aluminium straight edge to show me the high spots, just by rubbing it backwards and forwards:





That smear of grey is oxide of aluminium, and all you do is plane off the high bits that it reveals.

Oh, and by the way............that's what a workshop floor should look like, you extraction fiends. :lol: :lol: :wink:
 

MikeG.

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I was developing a small pile of scrap by now. Just to give me a mindless task for half an hour I made the wedges and support blocks, using up the scrap pile in the process. All done on the bandsaw:



After that orgy of machining (the stock preparation and cutting to size of the treads and risers had alone taken over 2 days), I felt the need of some handtool work. Time to make the brackets.

I printed out full size my drawing, and pasted it on a scrap of MDF. I used this as a template just to draw around, and then cut out the brackets on the bandsaw:



I had taken the unusual decision to dovetail the joint between the brackets and the risers. This meant that ideally they would be the same thickness, so the stock for both had been machined to 12mm. After sanding the edges on my mounted belt sander and just a little hand finishing, then running a tiny chamfer to remove the arris, they were ready for the dovetailing:



Locating the bracket in relation to the risers was the biggest head-scratcher of the whole job, by a country mile. Neither the top nor the bottom lined up, with the bracket being 30 or 40mm narrower than the riser. I calculated, offered up and marked, calculated again, offered up again......and in the end just had to make a decision and live with it. Seriously, that was a sleepless night.

Tails first:





Someone here (UKW) insists that chopping all the waste out with a chisel is the quickest way, rather than using a coping saw, and that a relieving cut up the middle of the waste helps its removal. Well, I tried it, and it was decidedly second best. the waste jams horribly on tails this small. The half done with a coping saw were quicker and cleaner:



I set an adjustable square to the dimension I had sweated over for so long, and chopped out the sockets. Dry fit:





That was the trial board, and everything was left over-long for potential adjustment, hence the deepened sockets. This was one of the subsequent boards (time to sort out that RAS blade!):



Then a few hours happily spent with marking gauge, knife, saw, chisels and mallet:



I glued that lot up and left them to dry overnight, and tackled the three tenons on the ends of the strings to take to the newel posts (1 at the bottom, 2 at the top). Mark, knife cut, chisel chop, saw, chisel, router plane:





(That's a Sandvic. Great saw.....and being 12" long the perfect length for a job like this).



I cleaned up the dovetailsthe following the morning, and did a trial assembly:





It's worth noting that the two strings still have no commonality. I had to prop the straight string on piles of off cuts to bring it up level with the cut string. When it comes to the final assembly I shall by doing this more carefully, and with a spirit level.
 

AndyT

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That's a lot of impressive hard work!
Is your bad back better?
 

Doug71

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Trevanion":14ifxim3 said:
That is the only downside with stair trenching jigs, they leave a little radius on the riser/tread junction which can be unsightly but more often than not nobody notices. You discovered the workaround anyway!
When I made my stairs I used a scotia bead to cover the gap

Makes a nice decorative feature but probably a bit fussy for the style Mike is making.

step.jpg
 

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MikeG.

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Next job was the end caps for the treads. These are the part of the tread that project past the ballusters and the string, between the ornate brackets. First job was to plane the bits down to the right thickness, and cut a mitre on the end. I have a beautiful SCMS hanging on the far wall of my workshop, but it's big and heavy, and I simply couldn't get to it with all the bags of waste in the way, and finding somewhere to use it looked difficult too. Imagine a full sized staircase occupying the middle of your workshop!

So, I cut them by hand, and shot them on the shooting board:





There are minor variations at each step, so this wasn't a production run. Besides, I did my best to colour match them, so they were individually made:



They then needed rounding over to match the stair nosing, so first up are some shots of setting up the router table:







....and finally the resulting end cap. I suppose I should have mitred in the near end in a separate piece, but life is too short, and I just rounded over the end grain:







Difficult taking a photo one handed with a big SLR camera whilst trying to hold the joint tight with the other. I failed!

Now to the newels. These are cored with a piece of 45x45 softwood, which I first adjusted to complete straightness:



After seeing nothing but oak shavings for the last week or more, this was a change:



You don't want to see me ripping and planing boards, so here is the two stage glue-up of the first newel:



......and then jumping on a day or two, the second stage of the process. This is not the way to do it, I realised, and did the other two differently:





The job I had been looking forward too least was the bullnose bottom step. This involved bending solid oak around a 150 radius curve, and although I had 1 spare board just in case, I broke 3 pieces of scrap in experimenting before tackling the job for real, so I was pretty apprehensive. Firstly, I made up a former in softwood:





Note the tight angle on the near side of the top photo. This is to link into an under-squinted (half dovetail, if you like) element on the end of......never mind, the photos probably explain it better:



I reduced the 12mm thickness of the riser to just 2mm over the whole area of the bend. I then offered the dovetail element of the former into the corresponding part of the riser, and held it roughly in place:



I then applied an old towel, and some water:



The weight of the former and the towel started to curl the wood, and I just kept on checking, watering, and tightening the curve over the next 3 hours:





You'll forgive me for not having any "during" photos of the actual glue up, as it was hectic and fraught. First, I glue and screwed the former in place, and then hauled the riser around it carefully, anchoring one end with the dovetail/ under-squint. Once I finally got it all the way around the former (all this with glue smeared everywhere), I tapped it down into the groove on the underside of the tread, an clamped everything loosely, before driving in some folding wedges which pulled everything up tight. You can see that I had to pack the wedges out a little:









That was actually late into the evening. I had planned on leaving the board soaking overnight, but on my last check before going to bed I had found that it was ready, so I started a glue up at 10.30pm, which isn't always a great idea.The following morning I de-clamped, marked up, and cut it to size:





With a bit of cleaning up and sanding it looked OK:



What a relief. That was the biggest remaining obstacle to finishing the job. The rest is just donkey work.
 

MikeG.

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I cleaned up the newel post by hand:



The other two newels were made in one stage, not two, and this saved a faff with the plane getting an exact fit between the two pieces. However, it did mean a lot of glue spread in a hurry, and lots and lots of clamps:



I had to go back to the wood yard for more supplies. This is how all the wood for this stair started:



I mocked up two or 3 handrail sections for my wife to choose from, and very wisely she chose the simplest:





I had found the most perfect piece of 2" oak for the handrails at the yard, absolutely dead straight and blemish-free. With one sensibly place cut up the middle, at the correct angle, I could save time and waste:



I'm seriously short of space for dealing with big pieces of wood, and had also to revert back to my old horses:







That will plane down to 65x45mm. I've decided to do individual mortices for each ballusters, rather than a groove with infill pieces, so there will be no full-length routing on these handrails. Thank goodness, as I've no idea how I could have managed in the constrained space I have left to work in.

That brings us up to date. It won't be fast from now on as I am somewhat busy with work for a few days.
 

sammy.se

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Amazing WIP as always Mike, thanks for sharing with us!!

We're you tempted to mitre the oak on the newels, to give the illusion of solid oak?

Sent from my SM-G973F using Tapatalk
 

MikeG.

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I hate mitres. Hate, hate, hate them. They'd open up and make me look a fool. No, my cunning plan is to do some stop chamfers and a lowered panel which will be close to the join line and take your eye away. I also tried pretty hard with the grain matching, in one case using adjacent pieces from one board. I also chose rift sawn boards so the face and side grains weren't too contrasty. But you are right, I'll see the join.....
 
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