Friday, August 23, 2013

A Staircase Saga, Part 7: Making the Handrail.

With all the treads and risers complete, including the First Two Curving Treads, the next stage was to make and fit the handrail up the stairs. When there are winding treads, it is normal to have the handrail just going up the outside wall, where the treads are at their widest.

Creating the handrail profile.
In an earlier post I mentioned that my customer had found a handrail profile she liked on a US website. With some experimentation, I found I could get close starting with 60mm x 60mm material, and using my table saw to cut two rebates and then use three different router cutters to create the profile.
The picture from the US website, and my profile process.
One correction: Step 3 is actually a 22mm radius, not 19mm.
I need to start with sections of 60 x 60 material - jarrah. You can't just pop in to the hardware shop and buy this stuff!  The timber merchants don't carry this stuff anymore. It would have to be created. Almost the only way to find heavy sections of jarrah is through salvage. Specifically old bearers. These 4" x 3"
timbers sit across the stumps and support the floor joists.  While they were green when the house from which they came was built, they supported the floor (and the walls in a timber framed house) for that 50-100 years before the house was demolished. In that time the bearers have seasoned beautifully.

The sections of handrail I created started out as bearers - 4" x 3" timbers. The longest piece, at 3.6m (12 ') long, actually came out of the old part of my customer's house, where it had been for nearly 80 years. So nice to put it back into its renovated original home now as part of the handrail!

Step 1. Machine the 4" x 3" material into 60 x 60mm straight sticks, the required lengths.

Step 2. Cut the 25mm x 6mm rebates along each side of the base of the sticks, on the table saw.

Step 3. Create the bottom beads by running the router cutter in the rebates.
The router runs along the rebate, from below, to create the lower bead.
Step 4. Create the top big round-overs with a 22mm radius rounding-over router bit.

Creating the top round-over with the big 22mm radius bit.
Step 5. Create the small round-overs under the top, using a 6mm radius rounding-over router bit.
This one's tricky, a long reach. Rounding over the underside of the "breadloaf top". 
That's it! Profile created. Note: The secret is to have three different routers will the cutters set up in them, undisturbed until all handrails and balustrading is completed!
Not a clear pic... but you get the idea. Notice the two tiny  quirks on top?
Planning for the joints.
The normal height for a handrail is the same as that of balustrading. Under the Building Code of Australia, baustrading must be a minimum of 1000mm high. With balustrading on a flight, the top must be a minimum of 865mm when measured at the point directly above the nose of the tread below. While this does not really apply here, it was a good starting point to draw this line 865mm above and parallel to the nose line below - which is about at an angle of 34 degrees. Of course, where there are winders this idea all turns to mud as the angles change from nose to nose around the corners. So then we experimented, to find the best angles around the corners, and the best transition points for where these might meet the ones on the straight flights. After many lines were drawn on the wall, we then decided on the best line to follow.
Hand rail pillars fitted to the back wall on the agreed line. 
The hand rail pillar positions were worked out, and then fixed to the wall. The joint angles and positions were now determined.

One joint, drawn on the wall. Now for the bridle joints...

Cutting the joints and putting the rail sections together.
The interesting thing about these bridle joints is that they were different, depending on whether the tenon would protrude from the top of the adjoining piece or disappear into the adjoining piece.
Cutting the tenon on a bridle joint.
Remember the two tiny quirks along the top of the handrail? These were there to aid the accurate marking out and cutting of the joints, and were used to aid the accurate sawing of the joints. It worked a treat...  otherwise it would have been very difficult to have done the accurate marking out for the joints.
Nice tenon! ...For where the tenon disappears into the adjoining piece.
Nice open mortise! ...for where the tenon will protrude from the adjoining piece.
The three pieces from the back wall, with joints cut ready to glue up.
So how do you do accurate cutting of joints like this on site? It was made so easy by using my trusty "Saw Horse on Steroids", which was so useful for building the winders on site.  You can't do this kind of stuff easily or accurately with power tools. It's hand tool territory! The holding power and options of this bench are wonderful for this work.
Joints pulled up, rail in position on the back wall, and glue drying. Looking good! 
The top joint on the back wall. Protruding tenon has been cleaned off.
Glue dry, so time to clean it up.
Those tiny quirks are now removed with a curved scraper and then hand sanded smooth .
The curved scraper does a great job. Made from a recycled saw blade.
The long run being cleaned up. It's over 14 feet long!
The long run cleaned up and in place.
There was much deliberation about the two corners. With the rails meeting at complex angles, it was not going to be possible to have a clean joint on the corners. Hence the gap between.
Where the long run meets the back wall. A 25mm gap to remove any finger trap.
Where the back wall rail meets the lower section. Another 25mm gap.
Other than the polishing of the handrails, there is one handrail task left (other than the balustrading upstairs). See that bottom end in the pic above? I have still to make the finish... the handrail is to curve and and down, mirroring the curve of Tread #2 below it and dropping the equivalent of one rise. A spiral finish. Eehah! that one will be a challenge! That will happen sometime in the future.

After the handrails were completed, the trim along the walls around the winders were added. The staircase is getting closer to being finished.

To complete the staircase, the remaining tasks need to be done: the spiral finish at the bottom of the hand railing; the balustrading on the top floor; the making of the door into the "hidey hole" underneath the lower sections; and the polishing of the entire staircase.

What a great project. A pleasure and a privilege to make, too.

Thursday, August 15, 2013

Recycling old saws into scrapers.

Sometimes, an old saw is just not worth salvaging.
Sure, if good enough, the handle and bolts/nuts can be all be saved to use again when repairing or re-building another saw. There are times when it is the saw plate that will be utilized instead.

Amongst my huge pile of old saws awaiting rebirth, there was a very tired post WWII  Disston panel saw which had a ruined handle. The saw plate had a bit of surface rust, but nothing too drastic. I had a need to make some more curved scrapers for spoon carving, so set about cutting up the saw. This was initially done with a guillotine.
Saw meets guillotine ... 
Dividers were used to draw curves on the ends of the pieces of saw plate, and the guillotine and  heavy tin snips were used to remove much of the waste. The rest was done with a bench grinder, to create the final shapes of the scrapers.
The first few scrapers taking shape.
Once the required shapes are made good with a bench grinder, the scrapers's edges need to be prepared with a nice fine file. We are looking for a very clean edge , square to the faces. A burnisher is then used to create the burrs which make a cabinet scraper work like a fine plane - taking very thin shavings. Wonderful!

Custom shapes for scrapers.
While I had been making up a batch of convex curved scrapers for spoon making, another task came along yesterday. I am making handrails for a staircase at the moment, and I needed a concave scraper to help clean up the top curve of the handrails.

So I grabbed one of the incompleted spoon scrapers made from the saw above, and re-shaped one side with a concaved radius suitable for my requirements on this job.

The scraper will remove the lines left by the router cutters from the handrail top.

The concave side of the scraper and the type of shavings it created on the handrail. Nice. 
So simple and so effective. Scrapers are fantastic tools which are easily made my recycling old saw blades - so long as they are not too pitted from rust.

I usually make spoon scrapers with a different radius curve on each end. However with the one above, I chose to leave the saw teeth in place... as a reminder of where it had come from, it's former life.
It's a nod to that nice old Disston panel saw. It lives on!

Sunday, August 11, 2013

A Staircase Saga, Part 6: The First Two Curving Treads.

All this year I have have been privileged to be working on a big renovation, where I have been doing a wide range of carpentry and joinery work. An Art Deco home built in the 1930's, the house has been expanded upwards and outwards. The addition of a second storey brought about the need for a staircase. Another job for me, which I relish. Stairs are a wonderful brain challenge and have always been a great chance to push and test my skills.

Where possible, the old original jarrah roof timbers removed to make room for the top storey are being recycled back into the house by way of the staircase, window sashes, and many other uses. Most of the straight treads in the stair case are made from glued up rafters from the original roof.
Yep, it ticks all the right boxes...

Previous posts tell the story of the Staircase Saga thus far:
Part 1: Building a Staircase with Winders.
Part 2: Getting Started.
Part 3: The Big Flight.
Part 4: The Short Flight.
Part 5:  The Winders.

It seems that somehow I don't have a pic of the staircase with the winders completed which shows the missing first two treads.
Winders completed... now for the first two treads.
In the pic above, the lowest tread in the foreground,  is tread number 3. Completing the winders meant that treads 3 to 20 are done. There is still the handrail to do and a few bits of trim around the wall edge of the winding treads - however the priority now was to make the first two treads.

The original architect's plan, showing the first two treads poking straight into the entry hall.

In the original plan, these first two treads were going to stick straight into the entry hall. Discussing this one day, we hit on the idea of making these treads flow out into the room by both curving around to meet the walls on either side. It seemed like a really good idea! Another fantastic challenge for me, and I was looking forward to bringing the concept to reality.

Planning the curving treads.
If you have been following this saga, you won't be surprised to find I start out with a set-out board with a full scale drawing.  It was important first to transfer the positions of the newel posts, walls and other key features onto this board. In this house which is 80 years old, not many of the original walls and floors are square or plumb. I needed to record all this on the set-out board, as everything would need to be scribed to fit the existing floors, walls, and staircase structure.
Part of the full scale drawing board, showing the right hand end.
Never mind the walls and floors, the staircase was all being built to be square and plumb to the planet! So allowances for scribing and fitting would need to be made to all components. All of the winders in the first set were radiating from the same theoretical point in the newel post. The curves would also be drawn from the same theoretical point and from a similar position on the other end. The use of these points and careful marking out would enable the creation of a set of very accurate templates for various components for the two treads.

Formers, riser boards, and nosings.
I needed to decide upon the method to be used to make the curved riser boards. Years ago, I used the multi-kerf method to bend jarrah sides for a couple of coffins I built. I reckon that would be the way to do this. So I did some testing.
A rough test, but it was going to be a winner.
Using my trusty radial arm saw, a series of saw cuts were made across the stick (165mm (5 1/2") wide, leaving approx 2mm of material uncut. These kerfs were cut where ever the curve would be formed, plus about an inch either side. This way one continuous stick (19mm thick) would be wrapped around the face of each former to create the riser boards.
Cutting the kerfs with the radial arm saw.

The formers were made using 16mm (5/8") plywood and bits of jarrah.

Making up the former for Tread 1's riser board.
Lining blocks were glued top and bottom between the radial ribs - just like the inside of an acoustic guitar.

Former  with lining blocks ready to have the riser board attached.

You can never have too many cramps! Gluing the riser board to the former.
The riser board has a rebate running around the top edge, like a continuous barefaced tenon running full length around the top. This would be housed in a groove running full length of the nosing 15mm behind the front edge of the nosing.
Gluing a couple of layers of thick jarrah veneers to the back of the bottom edge of the riser board. 
The former for Tread 1 was made 20mm short of the width of the riser board, to allow for scribing of the riser. There was a 12mm (1/2") fall in the floor from one end to the other.  This 20mm protrusion was strengthened by gluing a couple of 2mm thick veneers around the curved sections.

The nosing for Tread 1 being glued up in its segments.
Each segment joint in the nosing had 6 dowels and a biscuit held with epoxy resin! Cramping it up was tricky, but worked well.

Accurate templates and the router with a long flush-cut bearinged bit would cut the sweeping curves in the nosing.
The rebate cut on the inside would hold the tread insert behind the nosing.

The groove cut on the underside of the nosing, to house the riser board. 

 
The two tread units completed and placed in their stack - except for the inserts. 
Tread inserts cut to fit. Time to do the installation!
The tread units were now complete, and ready for installation. This was going to be a tricky job, as everything would be to be scribed to size and position and fitted.

Installing the two tread units.
First I had to sand the floor in the immediate area to get the floor area ready.
Then I had to scribe the bottom unit (Tread 1) to the floor and walls.

Cutting the horns to length to achieve a snug fit to the walls.
Scribing the riser board to follow the contour of the floor.
The bottom unit was leveled using packers, and scribed to the floor contour using the old trick of a block of wood and a pencil at the lowest common denominator. It is as accurate as the cutting to the line, which was the next stage. It worked a treat, using my rusty hand saw and jack plane. With much checking of the measurements and position, Tread unit No 1 was screwed to the floor. Unit 2 was then made to fit the walls, and fixed to both Unit 1 and the wooden staircase structure in the correct position.

The inserts being fitted to the treads. These were nailed into place.
The final fixing job required me to climb in through a small hole in order to screw the top riser board to tread insert 2,  from behind. It was a squeeze but a great moment. This complex and demanding task was completed!
It's no wonder I'm smiling!! ...All treads now completed.

Righto. Now it's time to contemplate the handrail and wall trim...
I guess I'd better make the door for the hidie-hole too!

Saturday, August 10, 2013

Saw sharpening... a balance between rake, fleam, and set.

At the Perth Wood Show last weekend, I picked up a lovely Canadian-made Disston tenon saw from the second hand tool stand run by the Hand Tool Preservation Society of Western Australia. It's a beauty! However it just needed sharpening...
Yep, a very nice Disston tenon saw, with the handle in very good condition.
I have a few odd Disstons made in Canada. This is a new addition to my Canadian bunch. 

With a three day gig this week at a primary school doing woodwork with the K - 2 students, I needed another sharp saw on hand. I also had another tenon saw needing sharpening for the event -an older Disston saw. So it seemed a golden opportunity to get them both done during a window of opportunity I had on the day before the school program commenced.

The older Disston tenon saw, made in Philadelphia USA.
About the variables in saw filing - rake, fleam, and set.
In a nutshell, RAKE is the vertical angle of the face of the tooth, which also determines the aggressiveness of the cut. If the rake was 0 degrees, the face of each tooth would be straight up and down. FLEAM is the angle of the face of the tooth in relation to the line of the teeth. If the fleam was 0 degrees, the teeth would be filed straight across. Rip saws are commonly filed like this, so that the teeth work like little chisels. Crosscut saws are filed with fleam up to as much as 30 degrees, which makes the teeth like little knives as they slice through the fibres of the wood. Set is the applied by bending alternating teeth either side of the tooth line. Increasing the set widens the kerf cut by the saw, which stops the sawplate from binding in the wood. However, the wider the set the harder it is to push the saw, and the less accurate the cut. Dovetail saws typically have minimal set, which enables greater accuracy.  

These saws are going to be used mostly by small kids. I am still experimenting with filing angles and the amount of set which works best for the little people (age 4 up) who have short arms, limited muscle, and who are often using saws for the first time in their lives. This means that they are yet to get the hang of moving their saws in a dead straight line. The wobbling wrist and arm will tend to make the saw plate bind in the kerf, so a bit more set in the teeth than usual will help to prevent this. The trade off is that they have to remove more material to have a wider kerf, meaning more energy is required. It's a balancing act, and my experimentation is yet to achieve the optimum saw configuration for the little kids. The other ingredient in the equation is the type of material being cut. With the kids, I almost exclusively use softwoods and plywoods. With softwoods you would normally use a greater fleam angle than you would for hardwoods. So, I continue to experiment...

The new saw in the saw vise, ready for sharpening.
After jointing, shaping and setting the teeth, I filed the teeth with a rake of 30 degrees and a fleam of 20 degrees - hence the angles. The kids will be mostly crosscutting in softwoods.

Teeth being filed for cross-cutting, with a rake of  30 degrees and a fleam of 20 degrees. 

Two nice Disston saws, sharpened and ready for action.
I would have between 4 and 6 tenon saws in operation at the school. The picture below shows my standard "sawing station" set up. This 4 saw station is a bit like having 4 bench hooks set up on a pair of sawhorses. It also works really well, for right and left handed students.

The sawing station set up at the school ready for use. 
As I finish this post, I have completed the 3 day gig at the school. Eight classes of students had a great time  making stuff - using hammers, nails, saws, and a  pile of wood pieces. The saws worked flat out for much of that time. Amid all those cutting their pieces of wood to size, there are always a few kids who just love sawing! They might not make much, but they do create piles of little pieces! It's great seeing kids enjoying using tools for the first time. So empowering.


The verdict? For the really little kids, the 4 and 5 year olds, I reckon we might need just a little more set in the teeth...    I'm still looking for the right balance...