Monday, January 13, 2014

Making A Boat Paddle Tenor Ukulele - Part 6 - Sides + Front and Back

Okey-dokey, some time in the shed at last and getting back on track.

Sides
The moulded sides are well and truly dried and are holding their shape quite nicely.
The cutaway section is in two parts and needs some re-inforcing gussets to prevent chipping and to strengthen the joins.  I have chosen a couple of pieces of African blackwood, both for strength and because it matches both the fretboard and the headstock.


These two gussets will be glued in place before the linings are added to the inside.

Here is a view from the inside.


This end block will become the corner of the block that houses the neck.  It will be made from cedar for lightness and strength.
I'll cut a block from this piece of Australian cedar and I will also shape the mortice in it before gluing.  This so much easier to do while the cedar piece is long - it is also safer when using a router.


Gluing Up the Front and Back

The front and the back are made from book-matched thin (2mm) pieces of mango.
Before gluing, each piece has to have its glue-edge perfectly straight.  I do this with a plane on a shooting board.
This timber is not mango, but black wattle - but you get the idea.

The edge-trued pieces are glued together and held in place under tension by nothing more than masking tape.


A flat surface is placed on top to keep the drying skins from warping and this is held down with a small weight.

The finished results are shown with the mango skins dried and flat.


The skin on the left will be the front and that on the right will be the back.

 This skin is most highly figured of the two, and will look best on the back where it will be able to show off its lovely grain to advantage.
The other will have a sound hole cut into it as well as a bridge glued on top.


Finally I have cut some strips from what was left of the mango used for cutting the sides.  These strips will be used for bracing and strengthening pieces on the backs of the front and back skins.

Next time I'll work on the neck.

Monday, January 6, 2014

A Damaged Plane Blade - Bringing It Back to Life

I received in the mail a much abused Turner handplane blade from Dylan's newly acquired number 5 jack.
See the comments from this post
Turner Hand Planes

Here it is as he received it:


The blade is near full and shows signs that it has been sharpened in the past.

Sadly someone has abused the cutting edge over its life, so that it now looks like this:


One corner is missing and there is a chunky chip out of the edge near the other corner.  The bevel has become rounded chipped and jagged.

 It is easier to see the damage up close .........

The back shows that a previous owner tried to flatten as part of the sharpening process, but that is such a while back that rust has started to appear.


First step will be to square off the blade by grinding back the old bevel to remove all the chips and jagged points - leaving the blade straight from one corner to the other.
Bench grinder to the rescue.


Care must be taken to keep the edge cool so that the steel doesn't "burn" and lose its temper.


The edge, ground square from corner to corner.  Grinding a new bevel comes next.  Most handplane blades like this one use a bevel of 30 degrees so that's what I will use.

Once the new bevel is ground, it needs honing to remove the coarse grinding marks and to begin to form the cutting edge.


This bevel is well formed but there is a dag of wired edge on the left corner that will hone off on the oilstones as a secondary bevel appears.
This will be honed at 35 degrees along the front edge of the bevel.

I'll use coarse, then fine oilstones, and then finally a hard white arkansas stone for polishing.
This is so similar to the chisel sharpening that I showed back in April 2012 that I will use an image from there:


Just think of this chisel as the Turner plane blade OK.
Sadly, I packaged the blade up and posted it off before getting a shot of the finished bevelled and sharpened edge - rats!

When it arrives  it will go back in Dylan's number 5 Turner plane just like this one:

Happy shavings to all.