Handle end
The handle, and the Picasso shot engine contained within it, involve complex shapes, and building the handle involves similarly complex shapes. Personally, I am not very strong when it comes to numbers, so I won’t give a lot of measurements but will describe the steps of how I fitted it all together
Lipping the tenon At the rear end of the stock, there is a tongue of wood (tenon) 50 millimetres long. The “D”-shaped cross section side laminates do not extend all the way to the end and the tenon is comprised of the rectangular cross-section central laminate. The tenon is the basis of the joint between the stock and the handle.
The front of the Picasso shot engine abuts onto the rear of this tenon. Three small lugs protrude from the lower part of the front of the shot engine. To make allowance for the lugs, the lower part of the rear face of the tenon needs to be cut away. Using the saw, I cut out a rectangle 4 millimetres deep into the tenon, and 25 millimetrers up from the bottom. There was now a lip on the top of the tenon, and the lip was 5 millimetres thick.
To check the dimensions, I placed the front of the shot engine next to the rear of the stock. The lugs fitted up under the lip, and the edge of the taper on the front of the mechanism was flush with the top of the tenon, and I now had the shot engine nicely abutting the rear of the stock.
Trigger-guard middle-piece The handle features a wooden trigger guard. As well as reducing the chance of unwanted firing of the gun, the guard also reinforces and strengthens the handle assembly. The guard is crafted from a piece of wood glued under the tenon. The wood is a 200 millimetre strip taken from the same original piece of lumber as was used for the stock central laminate.
To make the joint, a rectangular section was removed from the piece. This section was 50 millimetres long (to come to the rear end of the “D”-shaped outer laminates) and 12 millimetres on depth. When dry-fitted on the tenon, the front of the piece came flush with the rear of the “D”-shaped side laminates
The trigger-guard middle-piece was glued to the bottom of the tenon, taking care that the sides were flush and parallel.
When the glue had cured, I removed drips and flattened down the wood. This left me with a blocky piece that needed cutting down. I had to work out where the trigger hole would be – which also defines the top shape of the trigger guard
I dry-fitted the shot engine. There was room for the lugs, and the bottom of the engine did not foul on the top of the trigger-guard middle-piece, but the trigger did. To get an idea of how things would be when the handle was assembled, I took a pencil and drew around the position of the trigger at rest, and also when it was pulled back fully.
The remaining wood (that would make the trigger guard) looked a little thin, and really needed to be bulked-up, so I glued on another thin strip of wood underneath. For this, I used a 200 millimetre strip of the square edge 40 x 8 millimetres.
When the glue had cured, I removed the unwanted extra width of wood with a saw, then flattened it with sand paper.
Then, using the coping saw, I cut away the unwanted wood to leave space that would take the trigger and my trigger finger. I made the cuts a little short of what might be ideal as, if later I found it needed changing, it is easier to cut away more, than it is to add extra.
I now had a prong sticking out from the bottom of the rear of the stock. This prong (the trigger guard) would engage with the handle, and be jointed-in. I trimmed the rear end down to make a tenon (tongue) which would be engaged with the handle piece.
The handle was laminated from several pieces. The core of the handle had its grain running along the length of the handle for strength. I had glued together two strips of 30 x 18 millimetres to make a single piece 60 x 18 millimetres. This would be central in the handle.
To join the trigger guard to the handle, I cut an angled slot into the handle-piece. The tenon on the end of the trigger guard fitted into this slot. I glued them together. To keep the plane of the handle true with the plane of the stock, I clamped a flat piece of spare wood onto the tenon at the rear of the stock, and lapped this over the handle piece, and clamped it. This piece was to hold the other bits true, and was not be glued, as it would be removed later.
When the glue had cured, I dry fitted the shot engine onto the gun again. The handle piece wouldn’t let it sit right. I drew around the rear profile of the shot engine, then cut it out with a saw. This was a little tricky as at this stage the unsupported trigger guard is thin, and could break if too much force is applied. But a bit of care and careful clamping in the vice let it work without disaster.
The shot engine could now slip in sideways, but there was, as of yet, no side support for the handle.
Side plates and mech The next thing was to install the 8 x 40 millimetre side plates. There are two side plates of course, but I fitted them one at a time.
The shot engine sits up in the handle, above the top of the stock. It has a flat top, and needs to bear on the top of the handle, but this is 5 millimetres higher than level of the stock, so the side plate has to be lifted appropriately.
I dry-fitted the shot engine into its slot, and laid on the side plate, moving it around till it all fitted. I marked where the side plate would go with a pencil.
Once one side plate was glued on, the handle was much stronger. I took the opportunity to cut out the shape of the handle and clean up the profile a little. It was starting to look like a speargun handle! I also cleaned-up the front of the side plate, taking the bottom to about 6 millimetres below the line of the bottom of the stock.
I dry-fitted-in the shot engine, and used it as a template to drill the holes for the securing screws through the side of the plate.
I glued-on the other side plate, let the glue set, re-inserted the mech, and drilled through from side that already had holes. I was gentle, trying to minimise the chance of removal of plastic in the mech.
As they sat, the side plates prevented finger access to the trigger. I took the opportunity to cut out the upper parts of the trigger finger hole using the coping saw. As this was the initial rough cut, which would most likely need to be fine tuned later, I left spare wood.
Building-up the handle The centre-plate of the handle was too thin, and needed to be bulked-up. I did this by gluing-on short pieces of the 40 x 8 millimetres crosswise. I did them one at a time, waiting for the glue to set, cleaning out the waste, then gluing on the next plate
Once the glue had set, I cut off the waste wood with a coping saw, and neatened it with the wood rasp. Then I glued-up the other side. I also did a bit of preliminary shaping inside the trigger hole.
I didn’t glue any wood onto the sides of the trigger guard, as I wanted it to be thin on the final gun
In profile, the handle was more or less the shape I wanted, but it was square and blocky. I took to it with the rasp and then improved the finish with 80 grit sand paper. The textured grain in the Tasmanian Oak came up a treat, with a brindle look (a like a brown camo suit).
It occurred to me that I could have left the rough texture left by the rasp for an anti-slip surface, but the brindle grain looked so good I thought I would sand it smooth and shiny.
The tricky bits were on the edges of the trigger guard. It was hard to get at them with the rasp and the sand paper, and I wasn’t sure what shapes I wanted, but persistence brought success.
You want the handle to fit your hand, and the best test is to hold it. If something feels sharp or uncomfortable, remove it with the rasp. When I tried the handle in my hand, it was a little longer than needed, so I trimmed about ten millimetres from the bottom.
Line clip The Southern Speargun was to hold one clip of shooting line. This line was to be retained, at the handle end, by a wooden clip. The clip relies on the natural spring in timber to allow the line to be slipped into a recess, and to be pulled out when the gun is fired.
The clip is located under the stock, with its rear abutted to the front of the handle.
I took a piece of eight millimetre Tasmanian Oak, and cut it 90 millimetres x 12 millimetres. Using a rasp, I removed a wide “U” shaped piece, 4 millimetres deep and 40 millimetres long. The recess started about 15 millimetres from the front end of the piece, and ended about 35 millimetres from the rear end.
In the rear end of the clip, I drilled two countersunk holes, wide enough to take stainless steel screws. I clamped the clip where I wanted it to be finally located, and drilled down through these holes, into the stock, with a 2 millimetre drill. This created pilot holes for the screw threads.
I screwed the clip on to the stock.
Using the rasp (followed by 80 grit sand paper), I shaped the front of the underside of the handle so that the lines of it aesthetically flowed into the lines of the clip.
And that was the construction finished. I had next to varnish the gun, fit the rubbers, screw in the shot engine, fit the spear and shooting line.
The construction steps were not really all that difficult, but its hard to describe them in words. If this all seems a little complex, and difficult, I have pictures, but too many to post, so if somebody wants something clarified, ask and I will see if I can provide a picture that explains it.
Ric
Attachments: |
File comment: The trigger guard extends into the handle centre piece, and will be glued in
handle-piece with mortise.JPG [ 30.47 KiB | Viewed 11619 times ]
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File comment: After the top side plates have been attached, the handle is built up by gluing on other pieces
building up handle.JPG [ 41.45 KiB | Viewed 11622 times ]
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_________________ Ric Fallu started spearfishing in Pt Phillip in the early 1960s, and never really stopped
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