Wood Designer forum
Design Questions: additional newel posts and straight tread|Page 5|Forum|WOOD DESIGNER
Home
Hi Michel
Thanks for that. I have had a look at it and will respond to you points in order.
I am OK with 5 newel posts. But please realise that I chose the straight to parts option for the stringers precisely so that I would not have to join boards for the stringers and then cut and finish curved parts.
Newel post #3 on the first flight right. I want the lateral offset back to 0mm(centred) as there is no space issue.
Newel post #1 top of first flight left. Lateral offset previous side back to 0mm as there is no space issue in the angle of the walls.
Lateral offset next side back to 20mm as there is a space issue against the wall. By my calculation this will mean that the post sticks out towards the wall beyond the side of the stringer by 7.5mm, which is what I wanted.
Newel post #4 Lateral offset back to 20mm as there is a space issue against the wall.
Newel post #2 is good.
Newel post #5 cannot stick out beyond the stringer at the side so much. There is a joist at the side to obstruct it. I think it can protrude 7.5mm only. a 90×90 post is sufficient there for space reasons and becasue it is enough just to carry a handrail. So with 90mm square post the Lateral offset of 10mm should give 7.5mm beyond the side of the stringer. Correct?
Steps: I am ok with recess of 20mm front and back for the steps. Could you please explain to me why you and Ness recommend a penetration of only 15mm(I had originally specified 30mm) when the stringer is 55mm thick? Are you concerned that that cutting away 30mm will cut too many fibres and weaken the stringer structurally? Remember, this is an open stair with no risers. Minimum 20mm sounds better to me!
The penetration on the stringers into the Newels was originally set to 50mm because I plan to peg the tenons so I need enough room for the peg to be effective and not pull through. 30mm is not enough for that. The top and bottom recess values of 25mm are ok. I don’t know what you mean by ‘Lateral recess I left at 12.5 mm as you entered.’.
The measurements: I notice that the change in measurements has changed the tread width and raised a flag in stairdesigner. See 3D image of stair with tread with of 238.77mm flagged. I am not sure I have made myself clear about the space available.
The first Flight. Newel #1 overpasses the second stringer but I didn’t include that in the length of the flight as that amount (now 7.5mm as I have specified it) would be absorbed by the 20-25mm space that I allowed against the long wall for ease of installation.
Yes, the first 2 stringers must have 20mm overpassing value vis-a-vis the first step.
The second Flight:
Forgetting for a moment Newel post #1, if we take the measurement from the Left hand side(outside) of the first left stringer, to the face plate(joist) at the head of the stair, we have 3149mm. Above that joist, and overhanging it by 45mm is the floor of the 1st storey. This is, in fact, the landing step. It overlaps the joist(in the direction of the start of the stair) by 45mm because I estimated that I would need 30mm overlap(as for all treads) plus an extra 20mm for the riser to cover the joist, as you have specified. I am 5mm short. so the overlap will only be 25mm on that last landing step. Just to be clear the floor above IS the landing step. So, I think I have 3149mm to spread over Flight #2 on the left hand side. So with 16 treads(not including the landing step) the tread width used to be 247.44mm which was OK. I need to be clear on how Flight #2 willl meet the Face plate(joist) at the head of the stairs. I think that, if you understand what I am saying you will see that there is no need for the 70mm landing step and that 70mm can be shared across all the other steps as in the original design. Does that make sense?
Yes I needed a riser to hide the joist.
I don’t know what a comfortable handrail height is. Can we say 875mm or is 900mm better these days?
I am attaching a slightly modified version of the file you sent me. I have changed the newel posts. Could you add a last rise and remove the small landing step and make the stringers, with the riser attached, and the top newel post end at the same pointso that they can be bolted as one onto the face plate joist. (I am aware that I have to notch the newel to accept the landing step or cut out a piece from the landing step to accept the newel post.)
I look forward to your response.
Cheers
Andy
August 7, 2014
Offline
Hi Andy,
lets take it step by step
first : 5 newels is more then enough. If you feel better with a intermediate newel on the lefhand side to start the second flight then this can be done. I put it there and aligned it with the back of the righthand newel of 120mm. You do not need an extra intermediate newel on the left side of the first flight. This is one is not long and you will never get any flexing there.Also there is no newel on the start of the lefthand side of the first flight. The stringer is more then strong enough to cary any load there.
About the steps . I changed the recess to 20 mm front and back . This is enough. I added again the lateral recess on 5 mm as you like it that way. I understand the router issue you have. Step penetration I set on 15mm.
I changed the penetration of the stringers in the newels to 30mm instead of 50 mm and gave a top and bottom recess for the tenons of 25mm as this is a good value for it . Lateral recess I left at 12.5 mm as you entered.
The corner newel on the back of the first flight. I aligned them flush with the stringer.
Now the measurements . Your first flight has a total length of 1595 . This is from the nose of the first step to the backside of stringer of the second flight. you have to add 20mm from the overpassing value of the stringer versus first step and adding 17.5 mm from the corner newel overpassing the stringer of the second flight. this is a total of 1632,5 mm.
The second flight has a length of 3019mm + the landing step of 70mm is now 3089mm.
I added a riser to the last step to hide the floor joist.
I added a handrail on the righthand side . There you still have to define the handrail value and banisters to your needs. Handrail height is usualy measured from the stepnose with a value between 850 and 900 mm
The fligth width of 850 is measured from the outside of the stringers. So any part sticking out like a newel post has to be added
step width in a flight of 850 mm with stringer of 55 is 740 mm. Depending on the step penetration you have to add the length of the tenons. In the case 2x15mm = 740+ 30 = 770mm
Is this approximatively what you need? If any changes need let me know
regards
Michel
Hi Ness,
I got your design and had a look
Yes, it does need a handrail on the right hand side of both flights. I had one when I started with a template but lost it when I started from scratch. I assume if I add one the system will ‘know’ what height it should have. If not, what is the usual height?
Not sure if you understood what I meant about the stair NOT being capable of being bolted to the walls. I think I need 7 newel posts. I had set them up as I wanted them in my most recent design, apart from not knowing how to get the intermediate posts to be square to the 2 corner posts, because I have not found a way of knowing at what distance from the start of the flight the post is located(and is that the centre of the post of what?). I don’t think a righthand corner newel to the floor and a left hand corner newel to the floor and just the bottoms of the stringers is enough to support the stair in a stable way, given that the left hand stringer would only be supported from the corner post and the faceplate on the joist 3149mm away. I am pretty sure the stair would flex at the beginning of flight 2 on the left hand side.
Perhaps I have not understood you properly. My other concerns are the installation. I assume you are talking about a 2nd lefthand stringer of 4m in length or more. Do you see it as being in more than one piece? If so how can its rigidity be ensured., remembering that it will NOT be bolted to the wall. Not sure if I have timber of dimension for a single piece.
My design was for a lower half comprising the 3 straight steps and the 3 winders which could be stood in place on its 6 legs. Then the prejoined 2nd flight could be lowered into the receiving mortices.
With hand rail it needs posts top and bottom and I would have mirrored all but the top one on the left hand side( but onlty extending above the stringer by 2 or 3 inches) for aesthetic reasons alone.
I tried to explain why the tenons were offset in the newels(to minimise the amount of wood on the wall side for reasons of installation) and the posts are 110×110 and 120×120 for aesthetic reasons which are valid for me
Not sure what this means in your post, ‘The total length of the second flight to be 3089+60=3149mm where 3089 is the distance from the left face of the 1st string to the upper face of the first floor joist. I’ve set the last right post and the end of left stringer up against the first floor joist.’ What is the 60? Did you mean the right face of the 1st string? Is 60mm the thickness of the string? You have it as 55mm same as me. Not sure.
Perhaps I have made a mistake in that actually I should have measured the available distance to travel from the overlapping floor rather than the joist as this overlapping floor is, as it were another step and the tread width really stops where it begins, and so actually the last tread should be the tread width PLUS another 30mm under the overlap? Confused?. I am.
I could do with knowing that you understand me and I understand you before I continue with the design.
I took on what you said about the dowel and screw construction but would prefer the mortice and tenon approach as I used to it. I had shoulders on the treads because I am not experienced with the hand router and they would cover any eventual mistakes.
I think that unless you have some reason why the design I outlined is not workable then I would like to continue with that and I would like some help making the software do what I want it to do. Then perhaps you could generate the cutting list and I could see if the dimensions are what I planned. At present I still don’t know, when I specify a flight width of 850mm with stringers of 55mm what is the actual length of the tread without tenons. Is it 740mm? I am guessing it is. And if I specify that the newel post should be greater that 55mm, does that have any knockon effect on the width of the stair?
Cheers Andy
October 4, 2012
Offline
Hi Andrew,
Sorry to reply so late, but my computer crashed yesterday and I spent most of yesterday afternoon trying to sort it out.
I found the software crashing it and things seem back to normal now.
For your stair, the model you posted has no hand rails is this on purpose?
I’m supposing that you’ll need hand rails at least on the second flight.
I’ve adjusted a bit the model you posted and set up as I would do this project.
The total length of the second flight to be 3089+60=3149mm where 3089 is the distance from the left face of the 1st string to the upper face of the first floor joist. I’ve set the last right post and the end of left stringer up against the first floor joist.
To this you have to add the corner newel post left off set.
I’ve also taken away the intermediate posts which are not structurally necessary, and extended the corner post to the floor.
If there’s no handrail you could also take away the last right post.
I’ve also set all posts to 90×90
This stair will work and be fairly comfortable
I also tweaked a bit the stings, making them curved on the left side to make a smoother flowing curve and making the nosing to edge 30 instead of 50.
I’ve set the step penetration into the strings to 15 without offsets and recesses, the 30 and various recesses are IMHO not necessary and will only make the build much longer.
I’ve also set step to newel penetration to 15 as this was set to 0.
I’ve set the newels to be centred to the strings, except the corner newel that I’ve left as you set it.
I’ve set tenons with shoulders on the strings to newels. You might consider using a simpler joint like dowel and bolt, much faster and easier to make, also much stronger that traditional mortise and tenon.
See this video:
Hope this is helpful.
All the best,
Ness
Hi Ness,
Sorry I forgot to send the .stair file. Here is how far I got with the stair in v7.
Cheers
Andy
Hi Ness,
I want to build and install a quarter turn stair from ground to first storey. It will be in oak which is currently in plank form, mostly 10cm thick waney edged. It was dry for a long time but lately less well kept but now under cover but not yet acclimated to the place it will be used.
I have a 50cm thicknesser/planer with spindlemoulder and fixed router. Just bought a hand electric router which I have no experience of. Plenty of experience with hand tools, saws planes chisels etc
The building walls are stone and mud and the interior has been framed in 2×4 and insulated lathed and plastered. While the framing is fine for the plaster, it is not so strong or supportive that I want to bolt onto it(it is actually largely free of the walls, to combat the potential for damp in an underground position and with underground springs). So, I have decided on a freestanding first flight and turn with the second pair of stringers tennoned into to the back right newel posts and bolted to the stair head(picture well 2.jpg). The weight bearing newels can be bolted into the floor which has been strengthened below to allow that to happen.
I am attaching lots of photos.
well 1. jpg is the general view of the opening. As you can see there are not many obstructions. The one problem I have is that the righthand wing of the french doors which you can see in the picture cuts the LH side of Flight #1. The long wall is a little wavy so I have taken an arbitrary line where the vertical laser line does not touch any part of it and this is between 20 and 25mm away from the wall at its bottom(on the floor). This is my baseline with reference to which the other positions are set out. The short wall by the doors along which flight#1 will run at a an angle no where near 90 degrees. Pictures corner squared.jpg, corner squared 2.jpg and corner squared 3.jpg (with the line projected to the ceiling showing the deviation better). I currently have no intention of trying to accommodate this angle in the treads (unless you have a simple idea) and was content to leave the small void there.
Where the laser line passes the plastered wall corner before heading for the door, it is about 25mm away (picture corner squared 3.jpg). With this layout there is 3143.5mm to the stair head plate (picture well 2.jpg and length of well.jpg) The last time I set it out I was about 20mm from the corner of the set square and had it at 3149mm which makes sense. I was at all times trying to maximise the run to get the treads wider. So I think a starting length of 3150mm would be OK unless you have something to say about difficulty of installation.
The height from lower to upper floor levels is 3029mm below the stair head. Not so easy to measure it in other places but I laid out the joists on the lower floor with the same laser as I’m checking other levels with so I hope so. Obviously the joists may have dried and shrunk and the floor boards have been sanded so there may be a mms in it
The width of the well opening in the stretch before it breaks out from the ceiling joists is 880mm at its minimum.
To allow comfortable installation from that perspective, I was thinking of a flight width of 850mm though I would like to make the treads as long as possible without making the installation difficult.
Stringers 55mm thick and 300mm wide. I wanted to pin the tenons with draw pins so the tenons should be 30mm thick, 240mm long and if I am to be able to pin without stressing the tenons or posts I need them to penetrate about 50 or 55mm minimum. I realise that this may have effects on the installation and would welcome thoughts about it. One pertinent point is that the upper floor has been laid and I overlapped the stairhead by about 45mm or so in order to mimic the overlap of the stair treads (30mm) and to take the stringer face of about 25mm thickness which will be bolted to the stairhead immediately below this projecting landing. This may interfere with lifting the second flight and locating it in the mortices of the 2 newel posts below.
I started the stringers as straight to parts in the design thinking to make all the cuts and finishing simpler
Treads 35mm thick to be tenoned into strings with shoulders all round.
Newel posts. 120mm square section for the inner corner post. 110mm square for the other 3 posts on the turn. The start of the first flight can be supported by posts of 90mm section, and the final post at the stairhead can be 90mm section. I tried to let them stand out a little outside the stringers. The one problem may be the top post by the stairhead.
Pictures Door cutting start of left first flight.jpg and Start of left first flight.jpg show the situation where the right wing of the French door cutting the proposed left hand of the first flight. It sweeps through about the first 15cm of the stair. I had thought about doing something to cut away the stair to let it sweep through. But I’d rather not complicate it and perhaps a door stop will have to do. If you have any ideas le me know.
If there are any other questions I haven’t answered in this then please let me know
October 4, 2012
Offline
Hi Andrew,
Thanks for buying the StairFile Optimised service.
I’ve seen your StairDesigner project and all the great work Michel has already done so the design is well under way.
I’ll wait to see the photos and descriptions and we’ll get the last details sorted.
All the best,
Ness
PS: a big thanks to Michel for his excellent advise.
Hi Ness,
OK I have bought the Stairfile Optimised service.
I have also installed Draftsight and opened the .dxf file that you generated from the original .sds file I sent your colleague. Much good may it do me as I have no idea how to use the application. I tried various things to get some measurements but failed.
Anyway, could we please proceed as you outlined. I will take photos and measurements tomorrow and post them with a detailed description of the project I have envisaged and we could take it from there. I hope you saw my latest effort in v7 which I posted this afternoon, so that you can see where I am going.
Till tomorrow.
Cheers
Andy
October 4, 2012
Offline
Hi Andrew,
The demo version can’t export DXF the export you did was just the DXF parameters for CNC so not at all useful to you.
I’d suggest you download and install Draftsight from our download page:
https://wooddesigner.org/membe…..raftsight/
It’s free and very powerful.
In the project you’ve just posted there are quite a few questions that arise.
To get an in depth revision can you buy the stair file service from our shop here:
https://wooddesigner.org/membe…..discounts/
I’ll wait till I get all the information before starting the revision.
Looking forwards to seeing the drawings.
cheers,
Ness
Hi Ness,
OK I tried to do a DXF export from File>Export. The 1. DXF…. option is greyed out. I next went to File>Export Options and selected DXF and clicked teh Export button. It created a file called DXF.sd-export but I am not sure if that is actually a DXF file. I am in the process of finding a free CAD app with which to open it and the one you sent me. Is this the behaviour you expect from the demo version?
Cheers Andy
1 Guest(s)
