Changing a square newel to a turned newel.

Preparation.

It is worth getting the newel turn, spindles and handrail parts (Illu’ 3) made before cutting the post down, this will allow you to determine the the height of the post before cutting and having some tolerance in the length of the handrail for adjustment once the post has been cut.

Opening cap.

The opening cap size will depend on personnel choice a lot of the time, I find a good balance is normally about 1 ¾ to 2 times the width of the handrail, the one in this illustration is at 1.9 times the handrail width. (Illu’ 4)

This may change depending on the profile of the handrail and how the straight section of the under ramp cuts into the opening cap.

It may be best to draw the opening cap and handrail profile out before getting the cap made.

To find out how the cut angle is calculated and to be able to draw it out, see our article on how to get the cut angles for an opening cap.

Under ramp.

To determine the size of the under ramp, (Diag’ 1) it is best to keep the springing line at the bottom of the under ramp about 50mm 2″ away from the outer edge of the opening cap.

We know that the cap is going to be approximately one handrails width in radius, plus the 50mm/2″ of straight to allow for adjustment, therefore the straight on the bottom of the ramp will need to be 1 handrails width plus clearance, about 200mm/8″ should be enough, it will not harm making this a bit long; as this will be cut to length once the post is fitted.

The top section of straight, at the other end of the ramp can be about the same length, this will be adequate to bolt to the main straight section of handrail.

The curve used for the change in pitch will depend on personal choice, I would normally use the minimum of around 250mm/10″ for the internall radius and generally prefer about twice that to give a comfortable transition.

Newel turn length.

The turn length will be from above the closed string or stringer capping to the underside of the new opening cap position.

Newel stub height.

An allowance will need to be left above the stringer capping for the dressing of the newel post, this dressing of the post is to give the impression that the newel stub was turned as part of a newel that had the turned section done at the time of manufacture.

This distance will also accommodate the newel dowel at the base of the turn, this dowel is used to locate the new turn into the existing newel stub and should sit above the tenons from the stringers to avoid cutting into the tenons and weakening the joint between the stringer and newel. (Illu’ 5)

Height gain for under ramp.

The handrail will lift in height from its original height, with the under ramp and opening cap sizes calculated, a rod may be drawn to show the lift in height.(Illu’ 6)

Total newel turn length.

The total length of the newel turn is from the top of the stub newel where it is cut to allow for the newel dowel, to the underside of the under ramp. (Diag’ 2)

The overall diameter of the newly turned newel section should be a minimum of 6mm ¼” smaller than the width of the newel post

Cut the Handrail.

First, the handrail will have to be disconnected from the newel post and the first couple of spindles (ghosted in illustration.) removed to get longer spindles turned.

When the fixings can be found, the handrail may just be undone, when the fixings are not obvious or will not come undone then the handrail may be cut away from the post.

This is best cut about 100mm or 4″ away from the post to avoid cutting into any fixings. (Illu’ 7)

Cut the newel down.

With the cut height determined, the newel post can be cut to height and levelled.

It is important to get the top of the cut level as the new newel will use this as its base.

The top face may be planed or sanded level, I will normally use a belt sander for this; as working on end grain with a plane can prove to be a slow process.

A set square may be used to draw the cut line around the post, I would then cut from the first corner along the first face, cutting to a depth of about 6mm 1/4″, I will work around 3 sides like this, then I will cut the full way through with the saw. (Illu’ 8)

this keeps the saw guided on the face I can’t see, by the cut already on the line.

Draw diagonal lines.

Once the post has been levelled the next stage is to draw diagonal lines on the top surface, these will be used to find the centre for drilling the hole to take the new newel post bottom dowel.

This is best done before the edges of the newel post are removed in the dressing in stage. (Pict’ 1)(Illu’ 9)

Draw Newel post base size.

Draw a circle the size of the newel turn base or the size that you want the top of the post to be shaped to, on the top of the newel stub. (Pict’ 2)(Illu’ 10)

In the pictures for the cast newel, the newel is much smaller than the stub, in this scenario I find it is nicer to leave a fair amount of flat land around the base of the post, it normally looks better when the top circle is bought in about 3mm 1/8″ from the edges of the newel stub.

In the picture you can see the circle on the top of the stub is about the same size as the stub itself, this was probably as I did not have a compass with me and found a paint tin or something on site that came close to the size I wanted.

Marking the sides of the post.

To get the marks for the sides of the newel post, a diameter about 1 1/2 times the width of the post is suitable, in the picture here I used a paint tin that was nearby. (Pict’ 3)(Illu’ 11)

The easiest way is to make up a template, from a thin peice of material the same width as the newel, with the curve shaped on the top of it, making sure the curve is symetrical over the centre line, then offer that up to each face to draw round.

When using a paint tin or other circular item to draw the curve, cut the teplate material to width and use a set square to draw a line across the template, then set the tin with the curve touching the line at both sides of the template, this should ensure symetry.

When you have a compass at hand, it is easy enough to mark a centre line and measure down from the top, to get the curves drawn on.

Shape the sides.

Most of the material may be chiseled away, this can be done by chiseling upwards, to save the newel splitting out along the grain. (Illu’ 12)

This will be awkward over the tread and a spoke shave may prove easier.

If you are adept with a belt sander, these can be shaped quite quickly.

The power tool of choice is a power file, these are easy to minipulate and you can see more of what you are doing than with a belt sander.(Pict’ 4)

The shape of the post is to resemble a turned newel stub top, therefore the sections chopped away should be domed.

Drill for the turn dowel.

With the newel stub shaped, the hole for the dowel on the bottom of the new turned section may be drilled.

When confident with a drill in that the hole will need to be kept vertical and that the drill bit may try to wander; as it is going into end grain. A hole may be drilled to the required depth to take the dowel.

The safer option is to make a simple platform out of a piece of scrap material, that will act as a base for a router to sit on.

This platform can be any peice of flat material with a hole cut into it that is the same size as the newel stub. This can then have a piece of 2 x 1 screwed on two opposing sides of the cut out, the platform can then be set over the newel stub and clamped level with the top of the newel stub and checked with a spirit level. (Illu’ 13)

This can then be used to confirm the top of the stub is level.

Draw a circle on the top of the newel stub for the size of the turn dowel.

A hole can be drilled that is smaller than the finish size required; to remove the bulk of the material.

Using the router set to a depth of around 9mm 3/8″ and gently trim the hole to the size of the dowel, the router may now be set to a greater depth and the hole routed out close to the edges but can be a couple of mm 1/8″ away from the edge.

The final cut can be done with a top bearing guided router cutter, that is set for the guide to run round the initial routed face that was cut clean to the dowel size, this can be moved down as many times as necessary to get the required depth.

Determine the cut angle.

The first stage in fitting the new parts is to cut the “v” joint into the opening cap, as this will give the bottom end cut position for the under ramp. (Illu’ 14)

To determine the angle, width and depth of the cut, see how to here.

Cut the cap joint.

With the angle of the joint determined the next stage is to cut the “V” into the cap. (Illu’ 15)

To see how this is done.