An interesting roof.

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ScottyT

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As the title suggests, I recently completed a really interesting roof, fairly large given it was only me working on it, and fairly complex given the nature of the intriguing hoops that were to be placed ‘around it’
The entire thing was from Iroko.
I’ll post up in a few sections as Im still feeling my way round on here.

i should of got more detailed photos along the way but had no need to really, if there is interest in my work on here perhaps I’ll take some more in depth photos on whatever I may be doing in the future.
First up I had to set out the plate on the floor of my workshop, it’s in an old hay barn and the floor is up and down like a Weston donkey so it takes ages to level up with a site level. I use string to set out most perimeters and to find centre, and I can then set where my central boss will be and plumb that up for finished height from underneath the plate.
The plate itself was 305 x 90, standing on edge and mitred! To get things like an arrow I set up extension tables on the surfacer to get a really nice face and edge, then finished up on the thickness machine. I want to say it was something like 3.6 and 2.4 in length, two of each, So fair in weight.
Once they were the rite size I cut a fairly rough mitre and then finished with a smoother to dead(ish) 45. It took some time as they were massive 45’s and the only option was by hand, iroko doesn’t suffer fools with tooling either so it was just about settling in and tackling 8 at once.
FB1DAADD-920F-4D54-8F26-B0DF0FE302B0.jpeg

Here is the first photo I could find of it, those 4 pads you can see are all level with each other and the central pad as the ‘X’ marks the spot centre mark on it, so it’s all set ready for the plates to be slung on.
E70D7C3D-A18E-4BA6-BAE0-9BB7DD439D73.png
I
It is a bit tricky to smooth the ends and not chip any out on the really delicate end, but they went pretty good with a nice sharp iron, It taken some time to get the plate square, the tolerance was very tight so it was a case of trying and retrying until the tape read correctly.
FCC44914-AEAD-4928-AAE0-B1C6E66AAC85.png

and there is the plate, nice joints and squared up so it was time to work out the rafters now, double curved 125x90 (from memory) up to a central round boss, and they live with in the plate, tucked rite into the corners. I can remember working out the mortices for the boss was tricky as they were offset from each other due to the plate being a rectangle.
more on that in the next post.
B54F89F1-864C-4F84-8FC3-52AD89081CF9.png
 
As the title suggests, I recently completed a really interesting roof, fairly large given it was only me working on it, and fairly complex given the nature of the intriguing hoops that were to be placed ‘around it’
The entire thing was from Iroko.
I’ll post up in a few sections as Im still feeling my way round on here.

i should of got more detailed photos along the way but had no need to really, if there is interest in my work on here perhaps I’ll take some more in depth photos on whatever I may be doing in the future.
First up I had to set out the plate on the floor of my workshop, it’s in an old hay barn and the floor is up and down like a Weston donkey so it takes ages to level up with a site level. I use string to set out most perimeters and to find centre, and I can then set where my central boss will be and plumb that up for finished height from underneath the plate.
The plate itself was 305 x 90, standing on edge and mitred! To get things like an arrow I set up extension tables on the surfacer to get a really nice face and edge, then finished up on the thickness machine. I want to say it was something like 3.6 and 2.4 in length, two of each, So fair in weight.
Once they were the rite size I cut a fairly rough mitre and then finished with a smoother to dead(ish) 45. It took some time as they were massive 45’s and the only option was by hand, iroko doesn’t suffer fools with tooling either so it was just about settling in and tackling 8 at once.
View attachment 131961
Here is the first photo I could find of it, those 4 pads you can see are all level with each other and the central pad as the ‘X’ marks the spot centre mark on it, so it’s all set ready for the plates to be slung on.
View attachment 131962I
It is a bit tricky to smooth the ends and not chip any out on the really delicate end, but they went pretty good with a nice sharp iron, It taken some time to get the plate square, the tolerance was very tight so it was a case of trying and retrying until the tape read correctly.
View attachment 131963
and there is the plate, nice joints and squared up so it was time to work out the rafters now, double curved 125x90 (from memory) up to a central round boss, and they live with in the plate, tucked rite into the corners. I can remember working out the mortices for the boss was tricky as they were offset from each other due to the plate being a rectangle.
more on that in the next post.
View attachment 131964
The rafters were worked out on a sheet of mdf, from my given length and height and I messed about with a few radiuses until it looked about rite and cut it out using an old router connected to a piece of ply marked up with my radius points in relation to my where I needed the cuts.
I then had my template that I slung onto some 4” rough sawn, drew round it, banded it, planed and thicknessed, and then finally ring fenced on the spindle to match my template exactly.
the tenons on top of the rafter were being located into a round boss, therefore the shoulders had to be curved to match this, even though it’s 5m up In the air it has to be a clean job.
5272CC59-E669-4490-ACCA-95B8A0E5CB26.jpeg


DA8F458F-3373-48F6-A14C-78C97628C8FE.jpeg

here’s the rafters fitted into the boss, they still need machining on top for two angles to shed water, and one rafter needed a 3/4 x 5/8 groove all the way up it to take a cable for the light. You must always tenon before doing anything with you edges otherwise you’ll blow your shoulders out on the tenon machine.
0E0ACD77-2A8B-43E4-A161-9E4C90EDA907.jpeg

all looking pretty clean for the dry fit stages so i was ready to drop the rafters in to the plate now. A strange design this one and not the way I would of done it but this was how the client wanted it so that was that.
basically my plate sits onto 4 230mm square corner posts, flush on the outside, and the rafters are contained by my plate and sit directly on top of the posts along with the plate.
4189B4F2-18F5-4BDD-92F3-EA8BFEF0F864.jpeg
Rafters are ready to sink into the plate. Only photo I’ve got of it like this so my girls have made it into the shot too.
they work it all out for me and I just do donkey work.
 
The rafters were worked out on a sheet of mdf, from my given length and height and I messed about with a few radiuses until it looked about rite and cut it out using an old router connected to a piece of ply marked up with my radius points in relation to my where I needed the cuts.
I then had my template that I slung onto some 4” rough sawn, drew round it, banded it, planed and thicknessed, and then finally ring fenced on the spindle to match my template exactly.
the tenons on top of the rafter were being located into a round boss, therefore the shoulders had to be curved to match this, even though it’s 5m up In the air it has to be a clean job.
View attachment 131966

View attachment 131967
here’s the rafters fitted into the boss, they still need machining on top for two angles to shed water, and one rafter needed a 3/4 x 5/8 groove all the way up it to take a cable for the light. You must always tenon before doing anything with you edges otherwise you’ll blow your shoulders out on the tenon machine.
View attachment 131968
all looking pretty clean for the dry fit stages so i was ready to drop the rafters in to the plate now. A strange design this one and not the way I would of done it but this was how the client wanted it so that was that.
basically my plate sits onto 4 230mm square corner posts, flush on the outside, and the rafters are contained by my plate and sit directly on top of the posts along with the plate.
View attachment 131971Rafters are ready to sink into the plate. Only photo I’ve got of it like this so my girls have made it into the shot too.
they work it all out for me and I just do donkey work.
Next post which I’ll do asap is where it all gets a bit technical, hope you find this interesting
 
Great work mate. I did a very similar job to this in oak about 20 years ago and remember how challenging it was to get the neat joints with the heavy framing members working on my own. In fact yours is even harder than the one I did as the central boss/filial where the four hips met wasn’t circular so I could just use a flat plumb cut with a hidden tenon.

This is first order carpentry so please post a photo of the roof once it is in and I would also love to see pictures of the day that it is pitched too when the scaffold is still up etc.

Finally, me and a few other guys commented on a post on this site a week or two back about how tempting it is to underquote any jobs that have a circular component so as not to shock your customer. So I hope you put in a good price that rewards your efforts.

Look forward to a few more pictures.
 
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next up was two elliptical rings that rest over the top of the rafters, one small and one large. When the job got taken on the powers that be had no idea how we were going to go about making them, the long and short of it is to imagine a 90x90 post, in an ellipse, and then twisted on itself to from a diamond shape.
now from a machining point of view that is problematic, I work in the traditional sense, no computers, no CNC and no digital aid on the machines. It’s all very 1950’s. That said running a curve out is very simple, make a template, tack that template on top of your work, and either race it or ring it on the spindle and it’s all lovely.
the spindle is out of the equation here, I knew from early on the only way I was going to machine these curves was in half, running from the bottom on each piece. Not a chance of running it off the race as there is zero adjustment and we’re talking of a 45 face of nearly 5” to machine, both sides!
whilst I was mulling how it was going to be done I knew I needed a full size template that I could use to set the curves up on to maintain the ellipse. I could work everything out on of these templates, including how it would land on the roof, where lapped joints would go which in turn I could work the angles out too, and it would be a jig of sorts to glue up on at the very end.
I drew out my ellipses in the usual ‘batten and two nails off a square’ way and set about cutting them out. The large hoop was massive, I needed 3 8x4 sheets for it! I cut them out with a jig saw and spoke shaved them to final size. The centre width of the hoops measured around 135mm!
Once the full size templates were made, I worked out I only needed two curves to construct the entire hoop, if I placed them in such a way with enough length on them, I could make two identical half rings complete off my template, and when one got inverted to go face to face with the other, they would be the opposite of each other giving me a decent lap.
541AAEDF-51D3-478E-9983-A2AA1575BD21.jpeg


these templates are for the small hoop, it’s these I use to mark my rough sawn out from, and start the process of machining these hoops.
 
Now my full size template was made and my two templates to actually machine from were out I was ready to crack the curves out. I started with 4” rough sawn, chained them up to an approx length off my templates and loaded them on the forks to take down to the machine shop.
I surfaced one face, drew round my template and band sawed it out square to begin with. I’m now left with a square hunk of iroko following my template, approx 140ish wide by 105 thick!
luckily we have a very very old, very well engineered Sagar 30” bandsaw with a table that’ll go to 45 degrees, it will stop at nothing and it really is a testament to how we could do things back in the day, amazing.
I had to deep cut effectively two 45 faces off of my surfaced edge, it was the maximum the machine could do with the table cranked over, and a good strong arm was needed to keep to the pencil line through the saw. A shame I have no photos of this process, but when I did this job I did a few short clips for a mate and I still have them so you can better understand it.
The only way I could think of machining the 45s was on the overhead router, one of my favourite machines. I had a nice bed to work off of my surfaced edge, and I had variable height with the ability of the bed to move up and down. All I needed now was to be able to move in and out over centre cutter, for those who are not familiar with a OHR, it’s exactly as the name suggests, a router head over a bed, it’ll take up to 1/2 shank and has interchangeable pins that run up through the bed running centre with the chuck, I worked out I needed to do two passes off centre to get over my work, so i made a crude but effective bearing guide welded to some mild flat bar that I could move in and out at will, so I was set for machining.
 

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I left my OHR behind when I moved workshops in 2015 as it was only getting used about once a year and I wanted more space. It is paying off for you here though. You couldn’t do the last 2 of the 45 degree passes with a spindle moulder.

Thanks for the video.
 
It really was just a case then of getting down to it, the theory was to butt glue to tight joints all the way around the full template, masking tape every piece to said template and leave overnight, then flip the whole thing over in the morning, remove the tape and lift off the template which would then reveal the first half, flat side up, leaving me with my other half to glue up to in the exact same way as if I were using the template the day before.
The only difference being my template was now actually the first half of the finished piece.
A lot of cramps and titebond later I had my first hoop done. It all worked out no issues from start to finish.
5DEEF879-19A1-4E01-801C-5B12DC90E552.jpeg
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A little dry run to just check it all works.
Now for the big one to be glued up.
 
@ScottyT.
You've been with the forum 8 days, but it's clear you've found your spiritual home :cool:

Some lovely workmanship you do. Can I ask though whats the jointing methods on the mitred corners*. Is there some mechanical means or is it just Glue/pinned ?

*I've possibly missed you're explanation.

Nice workshop too, rather jealous :LOL:
 
@ScottyT.
You've been with the forum 8 days, but it's clear you've found your spiritual home :cool:

Some lovely workmanship you do. Can I ask though whats the jointing methods on the mitred corners*. Is there some mechanical means or is it just Glue/pinned ?

*I've possibly missed you're explanation.

Nice workshop too, rather jealous :LOL:
Haha your too kind, i very much enjoy what I do and I think it’s nice to share it with others.

The mitres were fixed using titebond and some big ratchet straps on site, they sat down on stainless locating pins on to the posts! Once the glue had gone off the straps were taken off, two 6x120 screws fired through the ends then plugged (1/2 counterbore just allows a 6 screw to snug in whilst keeping a nice fit in the bore for the plug)
Then to keep it all up there I fabricated out of 8mm mild plate some angle to take 4 M12 coach screws, 70mm long, two to go down into the post and two to go into the inside of my plate. That was that basically. I did the install too, the bottom section was made in the top workshop (im in workshop A at the bottom of the farm 😁) and the two collided on site.
 
I left my OHR behind when I moved workshops in 2015 as it was only getting used about once a year and I wanted more space. It is paying off for you here though. You couldn’t do the last 2 of the 45 degree passes with a spindle moulder.

Thanks for the video.
I love the overhead, we couldn’t do without it. Any excuse and im on it, so easy to do repeat work with very good accuracy. I made this lodge gate a few years back and the curves in the top and the lattice in the bottom was all done off the OH in a matter of hours. So good.
And that’s just one example of where this machine excels over anything else (in my opinion of course I respect others may see it differently)
F4840AAA-4CCF-46EC-8834-EB5C0F3A797A.jpeg
 
They are great machines especially for curved work. Technically my old OHR is still my property I suppose but I imagine that the guy that rents my old workshop considers it his now after 7 years; although I’m sure he wouldn’t mind me using it if it is still running. My customer’s arent asking me for nearly as adventurous a style of work as you’re doing. I am mostly making cabinets, doors, beds etc and doing heritage carpentry.

I like the gate but the twisted ellipses are really impressive.
 
The roof and the lodge gate are beautiful, fantastic work - in fact words cannot do justice to that level of workmanship.
BTW how is the roof to be covered, glazed or tiled or ??????? It will be a crying shame should your efforts not be on complete display.
 
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