Plastering Rounded Corners: Forming Quirks around Staff Bead

The plaster in our house has rounded or bullnose corners and we want to reproduce these in a new extension. My understanding of how these were formed is as follows:

A staff bead, a 1 inch dowel with approx 1/3rd shaved off the back, would be set on the external corner by the joiner on site fastened to wooden plugs which were set into the brick/block seams or to the wood frame. Plaster was run up to the corner then "quirked". In architecture a quirk is a small 'V' shaped channel used to insulate and give relief to a convex rounded moulding, and here it is used to hide the eventual small crack that will form between the staff bead and the plaster. I have attached a sketch to illustrate what I mean.

My question is, how best to form the quirk? I have read that you plaster backing coat (browning) right up to the outside face of the staff bead, and then cut out the quirk in the backing coat a little larger than the finished size. When you skim, again you skim the staff bead fully in and then using a straight edge, re-cut the quirk to the finished size, usually on an approx 45 degree angle into the bead. But this sounds a bit tricky to get consistent over a number of corners, and if all the quirks are slightly different it could look a mess. Does anyone know if there are special tools or techniques for forming the quirk other than just using a straight edge and experience? I am thinking of grinding a tool that would ride on the staff bead to form the two quirks at the same time but I have no idea how practical this would be. Any comments or suggestions gratefully received!

Regards - Brogden Fields

Brogden, I've no answer to your question but I've wondered how these corners were constructed, so thanks for your explanation!

hello Brogden,
I had some chimney corners missing and some damaged. I copied existing ones.
A rough diagram of the detail is attached below.
The building is around 1760 - 1780
The plaster edges were incrediblt square, protected by the dowels they remained very sharp even after 200 years.
I got the exact dowel size from Homebase and cut the fixing shape out of it with a plunge saw.
The wood strip the dowel fixes to was fixed to a corner timber that the laths were fixed to.
In another case, the dowel was nailed into wood wall pegs directly into the brickwork. (old wallplugs). The plaster edge was straight here also.
To replicate the square edge, I plastered against a piece of wood, then removed and replaced with the dowel.

On my house I think the whole job was done in-insitu using keens cement and a runner (1894) - no wood. And they manage to do the curved arch at the same time and down the other side (both sides). Perhaps they had a complete template which they moved from site to site and just pegged it to the wall as needed? Because of its size 4' wide 6" thick and best part of 9' tall and its very thin where it is bonded to the brickwork, I doubt if its a plaster casting which was bonded to the brickwork, unless it came in a demountable transit frame to protect it from the manufacturers.
Frank

What period is your house?

The most likely method would have been to make the whole thing in plaster, running it in situ like a cornice.

A thin metal template the shape of the corner would have been fixed in a rigid wooden frame. Vertical batterns would be fixed to both walls so the the box could be run up and down with great accuracy as the bead was formed. The same principle would be used in running the bead on a arch. My book on plastering shows a "hanging mould" in which a curved batten is fixed jut above the arch to act as a rail to guide the template which hangs below.

I will try to post pics when I have got to grips with by new digital camera.

ljn said:

To replicate the square edge, I plastered against a piece of wood, then removed and replaced with the dowel.

Click to expand...

Nigel Watts said:

What period is your house? The most likely method would have been to make the whole thing in plaster, running it in situ like a cornice.

Click to expand...

Hello ljn and Nigel,

Thanks for your replies. We think our house is about about 1860 / 1870 judging from the facade - I have uploaded a picture to give you a better idea.

I understand ljn's method, but it won't look like the quirked beads we want to achieve. We went to Henbury Hall which was built 1984-6 based on Andrea Palladio’s Villa Rotonda of the 1560s and saw the exact detail there, so we know there exist plasterers who have the techniques to do it.

Nigel's is wrong about the corners being run in situ. Although we do have have cornices that were run in situ {How to tell - you look at the edge where the cornice meets the ceiling: if it was run in situ it is usually very fine and, more importantly, exactly the same depth all the way around. If it is a moulding that has been stuck into place on the finished ceiling it will be very uniform thickness down the two sides where it runs parallel to the joists, but vary slightly in thickness on the sides where it runs at right angles to the joists} I know that the corners I am trying to replicate are constructed as I described with wooden dowels - it is easy to tell when looking at one of the corners in the existing house. Although I don't doubt that corners could be made the way Nigel describes, a corner run in situ purely in plaster would not have much strength to take the inevitable knocks, which is probably why dowels were used, and nowadays the metal corner bead.

Any further suggestions gratefully received!

Regards - Brogden Fields

That's interesting. My mother's 1928 house has a number of beaded corners which are definitely run in plaster. My 1840 house, although it doesnt have any beads, has wooden battens on the external corners such as the chimney breasts.

To answer your original question I think a hand held template may well do the trick. I used this method once to repair the edge of a cornice some four to five feet long. The result was pretty good.

You can run the "Staff Bead" on a bench in plaster, You are wrong to say plaster would not be strong enough, when we run staff beads we use either "Alpha K " plaster or "Crystacal R " both plaster's set very very hard.

hope this helps
hoppy

Nigel Watts said:

My 1840 house, although it doesnt have any beads, has wooden battens on the external corners such as the chimney breasts.

Click to expand...

Hi Nigel,

The wooden battens you have on external corners such as chimney breasts are exactly what I am talking about. These wooden corners are called "staff beads" when they are used in this application, and would originally have been quirked as I have described to hide the small crack that will form between the staff bead and the plaster. If your corners no longer have the quirk it will be because the room has been wall papered at some time and the quirks have been filled in to support the paper.

I am encouraged by your successful use of a template to repair the edge of a cornice - may I ask how you made the template, was it thin sheet steel or thicker, and how did you cut out the required shape?

hoppy said:

You can run the "Staff Bead" on a bench in plaster

Click to expand...

Hi Hoppy,

I had not heard of "Alpha K " plaster or "Crystacal R " plaster before - I'm not in the trade. Although I don't think I will use them this time it's useful info thanks. What staff beads do you use them for - corner beads like the one I am trying to reproduce? If so, how do you attach them to the corner, and wouldn't it be easier to run them in situ?

Thanks for the replies and suggestions guys, any more gratefully received!

Regards - Brogden Fields

We use "Alpha K" and "Crystacal" anywere hardness is required I.E skirtings, column casings, staff beads etc,etc.
running in situ is never easier, we only run insitu when specified by english heritage, architects etc,etc

aplogies in advance (No Advertising intended),, Brogden, if you look at our listing in the fibrous plaster section (PDS) you will see some images of staff bead we run on a bench and then fixed on site

I am not convinced that my house ever had quirked beads on the external corners of the chimney breast. I have no reason to believe that the wooden battens are not original and having done a good deal of replastering and plaster repair around them I found no evidence of any filled in quirk - on the contrary the wooden battens were all square. Traces of old wallpaper were found, which the V&A said were compatible with an 1840s date, so my belief is that the room was papered from an early data and, as you rightly say, quirked beads would have got in the way.

However I do have quirked beads on the junction between the staircase ceiling and the wooden string of the stair above. These had been filled in and papered over the years but I cleaned them all out. The areas needing repair were small and I did them by hand.

The template I used for my cornice repair was made from a piece of hardwood which I had first tapered towards the edge where I filed the profile, but I think a thin metal sheet attached to a piece of wood is the more conventional construction. I used a lime putty and plaster of Paris mix.

What a fascinating thread.
I only wish I'd had access to all this information a couple of years ago. But there are one or two corners of our house long overdue for some tlc where it will come in very handy indeed.

[quoteThe template I used for my cornice repair was made from a piece of hardwood which I had first tapered towards the edge where I filed the profile, but I think a thin metal sheet attached to a piece of wood is the more conventional construction. I used a lime putty and plaster of Paris mix.][/quote] If you are going to attempt to run insitu, you are going to want 0.005 guage zinc cut to profile, filed then attached to timber cut to same profile but set back 5mm (Running Mould).
Good luck

In my Wenselydale cottage the round staff beads have always been "unquirked", as they are nailed (blacksmiths made nails) into wopping big wooden wedges driven in between the limestone blocks. The lime plaster was finished off to the wood and I am wondering how to fill/repair the rather ugly cracks/gaps at this junction.
Frank

chuckey said:

In my Wenselydale cottage the round staff beads have always been "unquirked", as they are nailed (blacksmiths made nails) into wopping big wooden wedges driven in between the limestone blocks. Frank

Click to expand...

Hello Frank,

Are you sure they have always been without quirks? The method you describe for fixing the staff beads to wooden wedges driven between the limestone blocks would be the standard way of attaching the beads to the corners, and wouldn't preclude quirks - unless I am not understanding something specific about your situation. Forming quirks, even quite small ones, would be the obvious way of avoiding the feather edge resulting from running the plaster flush with the bead, and the cracks and breaking away of the feather edge that must inevitably follow.

Regards - Brogden Fields

Brogden,

My rather simple house (north Lancs, 1900 ish) has the same dowel corners you (and Chuckey) describe, crudely nailed into crudely driven wedges. I guess they didn't have too many options back then. In all cases the plaster has been taken right up to the bead forming a feather edge. Having read about quirked beads in one of Hugh Lander's books I have been looking carefully to see if any of my corners had quirks, but no.

Where I have had to replaster I have tended to replace the beads with new 22 or 25mm dowel. I have secured this by nailing a run of expanded metal mesh onto the 'back' of the dowel, then bending this into a right angle to attach to the stonework of the corner, either by screws into the mortar, or by dabs of plaster onto the stones. In this way it is possible to set the bead up vertical in both planes (near enough). Once plastered in the beads are solidly held along their whole length which I feel is a better solution than the couple of nails typically found in the original work.

In the first room we had replastered the plasterer used modern steel beads around the windows which just looked awful. When he'd gone I hacked them out and replaced with wooden beads as per the original. I've done all my own plastering since.

You are right about the problem of plaster breaking away at the feather edge where it meets the bead. This is not such a problem with gypsum plaster, but lime, being softer, does tend to crumble. I've cheated in places by knocking off the cracked featheredge once dry and making good with polyfilla, which seems to adhere to wooden bead much better. More often than not the room get the lining paper treatment anyway, so it's not such a problem.

If you do want to make quirks then I'm sure your idea of running a steel profile along the bead would work well. A bit of old saw blade or simialr would do nicely, filed to profile, or shaped on a bench grinder, or even with an angle grinder. I think the key thing would be to use a suitably fine mix for the finish coat which could then be scraped back when set but not dry. A bit of experimentation needed - have fun and let us know how you get on!

Andrew Bodenham said:

My rather simple house (north Lancs, 1900 ish) has the same dowel corners you (and Chuckey) describe, crudely nailed into crudely driven wedges. I guess they didn't have too many options back then. In all cases the plaster has been taken right up to the bead forming a feather edge. Having read about quirked beads in one of Hugh Lander's books I have been looking carefully to see if any of my corners had quirks, but no.

Click to expand...

Hi Andrew, it's interesting that you, like Chuckey, think that your corners never had quirks. I thought that when beads were used quirks were inevitably formed, but I guess that because this would add to the time and cost of the job, just plastering straight up to the bead may have been the "standard" or "economy" job, and maybe quirks were rarer than I thought. I know that none of the corners in our house have quirks now, but I was assuming that they had been filled in at some stage. I would like to choose one and carefully investigate, but this plan may fall foul of a higher authority who won't want her neatly decorated rooms despoiled!

Andrew Bodenham said:

Where I have had to replaster I have tended to replace the beads with new 22 or 25mm dowel. I have secured this by nailing a run of expanded metal mesh onto the 'back' of the dowel, then bending this into a right angle to attach to the stonework of the corner, either by screws into the mortar, or by dabs of plaster onto the stones. In this way it is possible to set the bead up vertical in both planes (near enough). Once plastered in the beads are solidly held along their whole length which I feel is a better solution than the couple of nails typically found in the original work.

Click to expand...

I had been contemplating the best way to fix the beads to the corner and your method is far better than anything I have thought of so far, and I congratulate you on your ingenuity. If I stick to the original plan and use wooden beads then I shall shamelessly copy your method of attaching them. However, I have been swayed by Hoppy's posts to consider bench run corners which can be attached and then plastered up to, which would probably save a lot of messing about on site and may result in a neater job. With the wooden beads it's quite difficult to disguise that the round bits of the corner are in fact wood; the grain always seems to show through.

I have also discovered that the details at each end shown in my original sketch where the round corner turns smoothly into a right angle before meeting the skirting board or cornice are called "birds beaks" - why? I have no idea; any explanation welcomed. However, armed with this knowledge I did a bit more digging and came across "Plastering: An Encyclopaedia By William D. Stagg, Brian Pegg" which contains the following sections on forming and running rounded corners in situ. Although I don't intend to follow either of the methods described I have uploaded it as it may be of use to somebody else. Interestingly, although the section on forming corners doesn't mention quirks, the running mould for running corners in situ clearly has the shaping for quirks built in to it.
As ever, any comments or contributions gratefully accepted!

Regards - Brogden Fields

"Bird's Beak"... when stopped in correctly, from a side on view your profile should resemble the same profile as a birds beak,,, hence the name

Brogden wrote:

Interestingly, although the section on forming corners doesn't mention quirks, the running mould for running corners in situ clearly has the shaping for quirks built in to it.

Click to expand...

In the text by Stagg/Pegg under the heading Angle, External Run, Internal Plastering the first sentence reads: "The three basic types of angle bead are the ovolo, the staff bead and the moulded chamfer." With fig 2. showing the running of a staff bead. It may interest you to know that the staff bead is also known as a quirked bead, as referred to in J. B. Taylor's book Plastering, published by Pearson (isbn 0-582-05634-9). It has a small chapter on running beads with a diagram on page 47 entitled Staff or quirked bead and text on page 45 which reads: "Run angle beads include a variety of moulded shapes, the most common being sunken ovolo and double quirked bead." though it's only mentioned in passing as it concerns itself more with metal beads.