Sunday, July 30, 2017

Traditional Upholstery Conservation: Uncovering Evidence

American Victorian Louis XV Bergere circa 1850
I have spent the past few weeks doing upholstery projects.  I finished conserving a rather large marquetry armoire and wanted something different to work on.  Upholstery allows me to hammer and that relaxes me...

You may have read my post recently about how modern museum methods are causing traditional upholstery methods to be lost and the craft of upholsterer subjugated to that of the frame maker.  As I was working on restoring upholstery I thought it would be a good educational post to demonstrate how I approach conserving upholstery in my business.

I had to recover two English Georgian Lolling Chairs, an early crewel wing chair, some embossed leather Belgium side chairs and a nicely made circular Victorian bergere chair.  All of these are now completed and the last one, the Victorian chair, provided me with detailed step-by-step photos of the seat conservation.

In general, I follow as close as possible the methods used by the original upholsterer , conserving the springs and stuffing material, except the cotton batting.  I replace the damaged elements using materials which are as close as possible.  Jute webbing, spring cord and twine, burlap, muslin and cotton batting are added as required.  If necessary, new 100% sterilized horsehair is added where previous stuffing was lost.

Here is a photo sequence of the procedure as it normally happens:

Bottom "Cambric" 
Usually a black muslin (called "cambric" is used underneath the seat.  This acts to keep dust from falling out during use.  These days it is a cheap fiberglass material which I detest.  I use more expensive black cloth when I can find it.  However, this chair was recovered at some point and the worker used burlap.

Replaced Jute Webbing
Removing the burlap exposes the springs, which are sewn to the jute, but only in a few places.

Evidence of Original Webbing
Under the replaced jute webbing is a fragment of the original webbing.  This narrow webbing was common during the 19th century.

Webbing Removed
Now you can see the failure of the burlap on top of the springs.  This is usually what happens when the cord breaks or the burlap tears.  The stuffing falls into the spring package and is damaged.  I always tell clients to stop using the seat when this happens and bring it to me for conservation before it is damaged beyond repair.

Back Foundation Still Good Condition
On this chair the original upholsterer did a fantastic job of building the back foundation.  It is not easy to work on circular backs and his work has stood the test of time.  I plan on leaving it in place as it is still serviceable.

Maker's Mark 
This chair was probably made in a large workshop where the number system was used on different styles of furniture.

Torn Burlap/Hair Dislodged
This is a close up of the torn burlap and the horsehair falling out of place.

Previous Conservation Stitching
This photo is sideways.  It clearly shows the original burlap and stitching used by the worker to create the front edge of the seat.  At some point another upholsterer was asked to recover the chair and he added stitches to the edge to hold it in place.  His stitches are the newer twine.  I was the first person to remove the seat foundation, which lasted 150 years.

Back Layers/Original Burlap and Stitching
This shows clearly the layers of the back upholstery.  The fabric is lifted up and the cotton batting is pulled aside.  You can see that someone added white horsehair to the original black horsehair.  Also the original burlap is stitched and tacked around the edge of the frame.  Undisturbed.

White Hair added by Previous Conservation
Now that the springs are clean on the bottom, it is time to remove the top foundation.

Original Burlap/Spring Cord/Twine
The horsehair foundation is removed and the original burlap is exposed.  It is rotten and must be replaced.  Note it is stitched to the tops of the springs.

Seat Foundation Removed/White Hair Added Previously
This is the complete original horsehair seat foundation, with white hair added later.

Underneath Seat Foundation
This is the underside of the seat foundation.  Care must be taken to remove all tacks from the edges.
It can be cleaned with a vacuum or actually washed and dried using TileX as a detergent.  If necessary it can be fumigated by a professional.

Original Spring Cord Undisturbed
Chair with seat completely removed.  The original spring cord is left in place.

Back Foundation Stitching Original
Again, the back is fine.  Just leave it in place for future upholsterers to admire.

Same Mark on Seat Frame

Cleaning With Alcohol/ Fresh Shellac Added
A quick cleaning with alcohol and a fresh coat of shellac restores the wood nicely.

Springs Sewn to Jute Webbing (4 knot)
It is important to stitch the springs to the webbing.  They must be placed carefully in a vertical position.  I use a curved needle and tufting twine.

Springs Sewn to Webbing
This shows the bottom with all the springs stitched in 4 places.

Original Spring Cord Pattern (8 knot)
The original spring cord in place.  I noticed that the outside springs are missing the diagonal cord.  This contributed to a weakness in the front center of the package, where the burlap broke down.

Note Method of Holding Springs
The proper technique for tying the springs is to hold them at different levels on the seat edges.  This makes the spring sit flat on the top and move directly up and down under load.  If the top only was tied then the middle of the spring would bulge out sideways under load.

New Cord Added over Old (8 knot)
I use Italian Spring Cord and tie each spring with 8 knots.  All cords are also knotted where they cross.  I added cord directly over the original cord.  I also added the missing diagonals which will provide more support to the front center.

This Will Last a Century More
Some might call this "overkill" but I want it to last under use for a long time.

New Burlap Cut to Fit Around Arms
To cut fabric around a wood element use the "Y" cut.

New Burlap Sewn To Springs
The first layer of burlap is added, tacked to the top of the frame and sewn to the springs.  If I were building a new layer of fresh horsehair I would also use twine to hold the hair to the burlap.

Lead Weight Holds Seat in Place for Tacking
One of the tricks I use in upholstery is to add a heavy weight to the seat while I am fitting the fabric or stuffing in place.  This tends to simulate the person sitting on the seat and allows me to pull the material from all sides without it moving around.  Note I added new burlap to the top of the seat foundation and this burlap layer is carefully tacked to the outside top edge of the frame.

Seat Conserved Ready for Fabric Selection
I use tufting twine to hold the seat foundation in place.  Since it is stitched to the new burlap it will work properly and not shift around.  I left all the older stitching in place and I suspect that the next worker who uncovers this seat will understand the various methods which were used to create it as well as the process used to conserve it.  It will survive as an historic artifact with all the evidence conserved in place.  In addition it will be providing comfort for the owner for many years to come.

POSTSCRIPT:  After some time the client finally came in to select the final fabric.  I have kept surplus upholstery fabric from jobs over the past 40 years.  It is getting difficult these days to find traditional material and anything made with natural threads, like cotton, silk, linen and wool.  This client selected a wonderful imprinted silk fabric, in a light green color.  I had enough to do the chair.

I should point out that tub chairs with deeply curved backs are fairly difficult to cover without wrinkles.  You need to pull the tension evenly top to bottom as you work your way around the curve.

Here is the final result:

Ready to go home.


Renewable Community Power said...

Fantastic stuff. I'm wondering how does the back foundation hold its shape so well?

W. Patrick Edwards said...

Many different materials have been used over the centuries for stuffing. Some of them do not last or perform well, such as rag wool, straw and excelsior (wood shavings). Others perform better, such as Spanish moss. The best material historically is animal hair, either from horse, cattle or hogs. This hair is processed to give it a curl, which lasts a long time.

Certainly the worst upholstery stuffing is modern foam, which quickly breaks down as a chemical reaction to the atmosphere, creating a disgusting solid that crumbles into a fine powder.

Feather down is in a separate category, as it provides loft and insulation, but needs to be manipulated from time to time to keep it loose.

The best hair is horsehair, and the best I have seen over the years is bleached white. Either white or black hair is worked by hand into an even layer, building layer upon layer to several inches in height. Trapped between layers of burlap, this hair is carefully and uniformly stitched in the center and along the edges to create the desired shape. Nothing else is as effective as this method to create a firm shape and provide comfort over many years of use.

On the back of this chair the foundation was in perfect condition, even after more than 150 years of use. The seat, however, broke down due to the tension and action of the springs, which is expected. Most conservation work in upholstery has to do with repairing the damage caused by springs, either on the bottom (jute) or on the top (cord and burlap). In most cases the hair foundation can be safely removed and then put back in place without much trouble.

This provides exactly the same degree of sitting comfort as was original when the chair was new.

That is the purpose of conservation and restoration, in my opinion.

maco said...

Just finished reading this post, it was wonderful. I was able to relive my joy and curiosity doing my first difficult upholstery job. Wish I could have seen how you handled the front edge/piping/top area? Sorry I don't remember all the correct nomenclature.
I am finally starting to read your posts. I discovered them thru Jack Plane's Pegs-and-Tails, and have spent many months reading his.
Looking forward to more.

Anonymous said...

Truly beautiful work, and I admire your keeping the original materials, whenever possible. I noted that the remnant of the original webbing was linen, not jute - no? As a textile conservator, I notice these things!