Kestrel Shutters & Doors – Blog

Posts Tagged ‘Woodworking’

Stave Core Doors & Shutters

Most of the shutters and doors we make here at Kestrel, both interior and exterior, are built out of solid, kiln dried wood without the use of any laminates.  We can do this as the wood species that we use, American Basswood and Sapele Mahogany, are dimensionally stable and react minimally to changes in humidity.

So what happens when you want doors or shutters made from a different species of wood that is not as stable?  If we were to make our doors and shutters out of solid woods like Hard Maple, Birch, White Oak and Red Oak, while they would be beautiful they would also be likely to warp.  Especially when made to the sizes of doors or larger windows.

This is where Stave Core enters the picture.

What is Stave Core?

When 2 or more pieces of wood are glued together the chance of warping drops dramatically.  This is because if any of the boards try to warp they end up “fighting” against the other boards and are held straight.  The only problem is that the glued up boards don’t look as nice as a single piece of wood.  So, you take those glued up pieces of wood ( that are now very, very stable ) and glue a solid, but thinner, piece of wood to each face and to edges as well.  This is what stave core is:  Thin strips of wood, laminated together to make them extremely stable, then covered in pretty much any wood that you want.

Mahogany stave core door stile

This photo shows a cross section of a Mahogany Stave Core door stile.  The front and back faces of the door stile are 1/8″ thick Mahogany and the edges are 3/4″ thick Mahogany.  These are wrapped around several smaller pieces of poplar.  All of these are laminated together to make a super stable stile which ensures that the interior door made from these will remain straight.

What are the Benefits of Stave Core Doors

Stability.  Using stave core for the stiles ( the vertical frame pieces of the doors ) will make sure that your doors will not move over time from changes in humidity.

Over-sized doors are not a problem.   This ties in with stability but the idea is that by using stave core for the stiles, and even the rails, you can have doors that are much larger than normal.

Eco-friendly.  Stave core is made up of smaller strips of wood that would otherwise have been discarded.

Lighter weight.  The cores of our stave cores are made from Poplar or Pine which are both lighter in weight than the hardwoods used on the outside of the stave cores.  This helps to keep the overall weight down.

Fixed louver sliding doors made with Mahogany stave core stiles and rails

Maple doors, built with stave core, cover a corner media center in this Hawaiian home.

Fixed louver sliding closet doors made with Hard Maple stave core

If you would like an option for stave core doors just make a note of that in the comment section of our quote request form.

Recently many customers have asked us about the hardwood pegs found in our doors and shutters. These pegs and their mitered layout on a completed frame are a signature mark of Kestrel Shutters and Doors.

The pegged mortise and tenon joint is a time honored cabinet makers joint with a use that extends very far back in time. Just google “mortise and tenon ship building” and you’ll see for yourself the amazing use of this joint. Even in today’s world, the pegged mortise and tenon joint is still one of the best wood fastening methods.

The peg, which acts as a cotter pin locks the connecting joint together. Pegs are usually pinned through the pocket joint and are revealed on both sides of the frame. However, one modern modification that we made to our mortise and tenon joints is to not have the pegs exposed on both sides. This design change allows us to provide our doors and shutters a distinct appearance to both sides. It also eliminates the slight possibility of the peg sliding out while doing it’s job in holding the joint together.

Our standard practice for our custom sized, made to order, wood doors and shutters is to build the frames with the pegs clearly visible on the front face. But, time to time, some customers do not want to see these pegs and for good reason such as the traditional joinery does not match their interior design. Whatever the reason may be, it’s an easy modification to have the pegs not show by inserting the pegs on the back side.

If having the pegs visible is a concern please let us know and we will accommodate your design preference.

Want to learn more about mortise and tenon joinery? Click here: Defining the Mortise and Tenon, Old and New

Kestrel Shutters & Doors, Inc. www.DIYShutters.com sales@diyshutters.com

Now in our 20th Year
May 4, 2009

If you haven’t read my posts before, I sometimes add other odds and ends to share…

I took this picture just the other day of Black Angus grazing on the lush June grass.

Defining the Mortise and Tenon, Old and New

The mortise and tenon joint is one of the oldest methods of joining two pieces of material together and certainly is still very much a mainstay in fine cabinetry work today. There are many references to mortise and tenon joinery throughout the ages. Historical monuments such as Stonehenge, the hulls of early boat and ship vessels, and even Egyptian sarcophagi were made with this frame construction. Whether stone, metal, or wood, the construction method is still very much the same.

The mortise is essentially a slot or a hole cut into or through one piece of material. The tenon is an extension milled onto another piece of material that will be fitted into the mortise. The outer dimension of the tenon matches in both shape and size to the inside dimension of the mortise. When the tenon is inserted into the mortise, the two pieces of material are joined.

In traditional woodworking, door and shutter frame mortises are milled into the vertical inside of each upright frame member. This upright frame member is called a stile. Mortises are placed where horizontal cross rails intersect. Cross rails, or simply rails, are the horizontal frame members. Rails are made over sized in length allowing for the ends to be milled down creating a tenon.

A well made deep fitted mortise and tenon is very strong since there is quite a bit of surface area contact between both pieces of wood. A snug fitting joint is the best as it will help to prevent the frame from racking. With the use of pegs, wedges or both wedges and pegs, as shown in the pictures of the shutters below, the parts are held tightly together creating a fastened joint.

These aged shutters are well over 100 years old. They are great examples to show mortise and tenon construction with the use of both peg and wedge fastening methods.

The shutter frames are fastened together with both pegs and wedges. The wedge is inserted in the opposite side of where the tenon was inserted. The peg is just below my thumb.

I pulled this wedge out for you to see. It is pretty amazing that someone a long time ago cut this and at least 11 more, all fitted perfectly by hand, for each pair of these exterior window shutters.

The mortise shown on these old shutters is called a through-mortise simply because it is open on both sides, milled all the way through the stile. This mortise and tenon was made to fit a wedge. The wedge pinches the tenon into the mortise slot and holds the joint together much like a wedge shape door stop holds a door open or shut.

Through mortises are seen on objects made in periods in time when milling machinery was not available or advanced enough in order to mill the material quickly and easily.

With the advent of machinery, through mortises for the most part were replaced with “pocket” mortises. Pocket mortises are just how the name sounds. The pocket mortise is open on one face only for the tenon to be received.

We have seen wedges used on many old shutters that we reproduced. However, since we use the pocket mortise and tenon method we only need to use pegs. Pocket mortises are very good for outside applications since end grain is not exposed. The reason that end grain should not be exposed is because just like a drinking straw will suck up water so does end grain. End grain is essentially very much like many tiny straws bundled together that supply the tree and it’s canopy with water. When end grain is exposed and proper maintenance is not provided it will eventually lead to deterioration.

More then likely these old shutters would still be hanging if they had had just a little more maintenance with finishing as it appears that this paint is the original finish. For being as old as these shutters are they are still held together rather well because of the well made mortise and tenon construction.

Pegs are inserted into a hole that has been drilled through the face of the shutter through the mortise and tenon joint. The peg acts much like a cotter pin locking the two pieces together.

The mortise and tenon joint is a very old construction method and still one of the best woodworking types of joinery today. Our interior shutters, exterior shutters as well as all of our doors are assembled using this method of joinery.

When we assemble door and shutter frames a light application of glue is applied to the mortise and tenon joint areas. Then the parts of the frame are fitted together along with the components that will be inside of the frame such as operable or fixed louvers or even solid wood panels. The shutter or door is then clamped together to tighten and flush all of the joints. When the joints are flush and tight a hole is drilled through the mortise and tenon for the pegs. After the pegs are inserted the joint is now locked together and the clamps are released. At this point this joint can take extreme force and still not pull apart and it will undoubtedly last as long as the old shutters shown in this post, if not longer.

Did you know? Just because a wood product can mention made with “mortise and tenon construction” does not imply that it is good unless it is properly made. When mortise and tenon joints are too loose, improperly fitted, the joint will fail and the frame will rack.

Post written by Jewel Foulds, April 2008

Spring is no doubt one of my favorite things. Nature is fresh and full of color. I was lucky to capture this picture just recently. This spring time beauty known as ‘Bleeding Heart’ is an Old Fashioned favorite in many gardens.

Kestrel Shutters & Doors, Inc. www.DIYShutters.com

Celebrating our 19th Year in business on May 4, 2008