The MA thread - AKA Everyday Fan Vault Construction for Beginners.

[Adam W.]

The ribs start off like this. I try to chop most of the waste off with an axe or froe and use the thick edge of the riven piece as the part where the moulding is going to be cut.

Cut them to length and shape the top edge.

Cut the waste on the inside curve into blocks with a saw and chop it out.

Plane it flat. The plane doesn't normally live like that, as I prefer to have it standing with the iron on the bench.

I don't fix the piece down whilst planing as I use the bench top to gauge for flatness. If it's skidding around, it's not planed flat.

Mark it out with the templet on both sides and chop out the double curvature with a firmer chisel down to the line.

Strike a line for the edge of the moulding with the second templet and draw a centre line along the inside of the radius. This line has to remain and I'll use it as a gauge line for the central bead of the moulding. I'll refine the radius later when I do quality control before finishing the moulding.

Then I address the top of the tennon to make it central before I cut it down to thickness, about 1/4".

There are thirty ribs and I've made thirty two for luck. There are also four longer ribs which join the springers together at the edges of the vault.

I'll now start to cut out the 1/2" boards for the cusping and sub cusping to relieve the boredom of all the rebating, otherwise I'll lose the will to live.

 

[Adam W.]

Whilst there's lots of planing going on, I get the chance to think about other stuff like joining all the bits together and how I'm going to deal with the spandrel.

I made this drawing before Christmas which simplifies the rib moulding without all the confusing detail of the cusping.

I can use sheets of paper to isolate sections, which I can make from quater sawn boards and duplicate eight times to make the rib moulding for the spandrels.

I think I'll just cut out a templet and dry join them together for carving. I'll have to watch out though as this segment isn't flat, but curves up towards the fan.

I've also been looking at a King Penguin.....

....for ideas on how to deal with the back of the turned springer.

I really like the dog carrying the load.

 

[paulrbarnard]

Whilst there's lots of planing going on, I get the chance to think about other stuff like joining all the bits together and how I'm going to deal with the spandrel.

I made this drawing before Christmas which simplifies the rib moulding without all the confusing detail of the cusping.

View attachment 126710

I can use sheets of paper to isolate sections, which I can make from quater sawn boards and duplicate eight times to make the rib moulding for the spandrels.



View attachment 126711 View attachment 126712

I think I'll just cut out a templet and dry join them together for carving. I'll have to watch out though as this segment isn't flat, but curves up towards the fan.

I've also been looking at a King Penguin.....


View attachment 126715

....for ideas on how to deal with the back of the turned springer.

I really like the dog carrying the load.

View attachment 126716

View attachment 126717 View attachment 126718

Given you have used oak it should be oak leaves and a squirel...

 

[Sgian Dubh]

Quite a few books in a short space of time..

How very odd. It sounds almost as if the thefts were coordinated, maybe even stolen to order or something like that. As I suspect we all know, academic books tend to be relatively expensive, so the theft of even five or six books can mean losses running into hundreds of pounds, and if there's no insurance in place ... well. Slainte.

 

[Adam W.]

Cusping and double cusping.

Continuing on a theme of templets, I've been making the insert template for the cusping and double cusping on the fans and concentric circles of the spandrel.

This stuff, there's lots of it and if I can get it to work, I'll save a big chunk of time.

My aim is to do it without setting each one out with a compass and use this templet instead to draw it and drop the bit in the holes of the double cusping to mark it and just bore it out, stick it together, carve the moulding and remove the central waste at the end.

The vine leaves get attached to the ends of the cusping later.

 

[Adam W.]

I'm finally getting my head around it.....


I need 16 of these and 32 with double the amount of cusping.

I may be......

some time.

 

[Fitzroy]

Gosh. You have a lot of skills and even more patience.

Wonderful thread!

 

[Adam W.]

@Fitzroy Thank you, I'm glad you're enjoying it.

I'm relieved to be cutting wood now, as I've had to do much more thinking and planning for this one than I'm used to. The production line will help me get better as I go along, so it's good practice.

 

[Adam W.]

Normal service will resume shortly.

 

[Adam W.]

Routed out and set out. This is where I'm stopping until I get the 1 5/8" centre bit for the sub cusping. I think it's going to save me quite a lot of time over the course of the 50 or so pieces which I need to make.

I had a blow out on the piece on the right and changed the order of working to avoid that.

I'll start on the spandrels now and do the more complicated conoid cusping once I've got the thing joined together as they are curved and need to match the curvature of the conoid ribs.

 

[Adam W.]

The spandrel....

Templets.

First fit.

I'm glad I've only got two of these to make and join so there are no gaps, and that they fit with the other 300 or so pieces.

I've planed the front flat so that I can join them together, then I'll plane the back side to depth. I think I might glue them up with RSG and chop the holes when it's all in one piece.

 

[Sgian Dubh]

I think I might glue them up with RSG and chop the holes when it's all in one piece.

RSG?

Resorcinol formaldehyde adhesive? Slainte.

 

[Adam W.]

RSG?

Resorcinol formaldehyde adhesive? Slainte.

Rabbit skin glue.

 

[Sgian Dubh]

Rabbit skin glue.

Ah! Thanks. That type of adhesive never entered my mind. I kept repeating RSG trying to find a lead in to the acronym, and then came up with resorc... which got me half way to the wrong answer, ha, ha. SSlainte.

 

[Adam W.]

Ah! Thanks. That type of adhesive never entered my mind. I kept repeating RSG trying to find a lead in to the acronym, and then came up with resorc... which got me half way to the wrong answer, ha, ha. SSlainte.

It's what I've got lots of, and I can undo it with a bit of heat if I screw a section up when I'm carving it.

Belt and braces all the way.

 

[Adam W.]

Ah! Thanks. That type of adhesive never entered my mind. I kept repeating RSG trying to find a lead in to the acronym, and then came up with resorc... which got me half way to the wrong answer, ha, ha. SSlainte.

Here's an handy comparison of various animal glues if you're interested......

Taken from

https://www.researchgate.net/publication/272311539_Animal_glues_a_review_of_their_key_properties_relevant_to_conservation

 

[Jorny]

I can't bring more to this thread more than saying that this is fascinating stuff to follow. I have been fascinated by gothic architecture since childhood, and even more so since architecture school.

 

[Droogs]

here is an overvue article by Yannick Chastang, one of the best modern maraquetarians around, for those that are interested.

https://www.marquetrycentre.com/wp-content/uploads/2014/01/FC192-P39-42-Glue-finishesDtfsfmb.pdf

He also did a fantastic Benchtalk 101 about his nearly 2 decade study of hide glues for use in his boulle marquetry. can't seem to find it on the tube just now though.

 

[Sgian Dubh]

Here's an handy comparison of various animal glues if you're interested......

Thanks. Yes, I'm interested primarily from an academic viewpoint. The truth is that if I reach for animal glue I only ever need to use one or other versions of hide glue, heat up type or the cold liquid type. I've not needed either for many a year, I must admit. Maybe I'll get back to doing some furniture restoration to generate a probable need to use hide glue again; that is if I ever feel like I want to get back into the game of being harangued by dealers or owners that want the job done for little or no charge, ha, ha. Slainte.

 

[Adam W.]

Spandrel piercing underway, temporarily glued together with RSG and I'll probably un-glue it before I fit the cusping inserts to permanently join the spandrel together.

Thanks to @AndyT @Tris & @MARK.B. for the bits, they work a treat.

Head down for the rest of the week if I'm going to get this one done