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PostPosted: 06 Jan 2010, 13:09 
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Seems that the pictures were lost from this particular thread, so I re-did the description of the build, and posted it on http://southernfreedivers.org.au/forums/viewtopic.php?f=3&t=4162&p=36117#p36117

I have also put in information on a DIY railgun, and it can be found at http://www.spearboard.com/showthread.php?t=153277



Original text
I wanted to make a gun that would suit local conditions, and could be built by someone without too many tools or wood working skills. The materials should be easy to come by too.

I dubbed it the Southern Speargun.

It features:
• 1.1 metre stock
• hand cut spear guides
• 7mm diameter, stainless steel, mono head, spear
• “Brett’s” closed muzzle
• single, dropped, 16 mm rubber, with a soft spectra bridle
• Picasso shot engine

I made the gun from Tasmanian Oak mouldings I purchased in Bunnings. It’s glued together with polyurethane glue sourced at the same place. The eye bolt in the muzzle came from there too. The spear etc came from Legendary.

I kept to tools to a minimum. I specifically avoided a router, and hand cut and individually positioned the spear guides on the stock. The primary shape of the stock comes from pre-cut mouldings purchased off the rack. I kept the handle simple (still trying to keep the lines flowing aesthetically of course).

Most of the shaping is done with a rasp purchased from a $2 store, followed by sand paper.

I am reasonably satisfied with the gun’s looks. The shapes don’t flow quite as fluidly as I would hope, but that’s got to be expected I suppose. The front of the trigger guard looks a little blocky to my eye, but it has to be robust to support the glue joint. I will work on the design, and maybe the next gun will look a little more elegant.

I deliberately limited myself to timber I took off the rack in Bunnings, but still managed to get a little variation in colour and grain, which adds a little to the looks of the gun I think.

The gun came in a little cheaper than something you might purchase off the rack (not costing the construction time of course) but there is no dramatic saving. There are ways it could be made cheaper – for example substituting radiata pine for the Tasmanian oak.

It took me about three weeks to finish.

How does it shoot? I haven’t taken it into the water yet, so watch this space for further postings.

I am very happy to share details of how I built it, if anybody is interested.

Ric


Attachments:
File comment: the tools used to build the gun (gluing clamp arrangement not included)
gun with tools.JPG
gun with tools.JPG [ 59.69 KiB | Viewed 12036 times ]
File comment: Handle and line clip arrangement
handle and line clip2.JPG
handle and line clip2.JPG [ 53.18 KiB | Viewed 12029 times ]
File comment: A "Brett's" muzzle
Bretts muzzle.JPG
Bretts muzzle.JPG [ 36.07 KiB | Viewed 12013 times ]
File comment: saw dust anti slip applied to handle
antislip on handle.JPG
antislip on handle.JPG [ 62.92 KiB | Viewed 12012 times ]

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Ric Fallu started spearfishing in Pt Phillip in the early 1960s, and never really stopped


Last edited by ric.fallu on 13 Nov 2012, 10:42, edited 4 times in total.
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PostPosted: 06 Jan 2010, 16:06 
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Thanks for that Ric! Hopefully that'll get a few of the guys started on their own!

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PostPosted: 07 Jan 2010, 20:00 
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Yeah great ric, impressed me so much i made it a sticky. Will help a lot of curious people.


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PostPosted: 07 Jan 2010, 21:13 
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I'm very curious and have a huge garage full of tools that i could make one with but don't have the time currently although i could do this over a number of weeks...

Might be in contact soon Ric. Cheers !


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PostPosted: 08 Jan 2010, 12:35 
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Hi Ric
Thank you for your posts and, in particular, this very latest "easy to build gun" which I believe is at the reach of most. I'll be very interested in reading/hearing the result of your tests in the water.
Have you ever entertained the idea of a club workshop? ... say, for example, a 30min run-through on the making of this gun before the start of a club meeting? or perhaps as an add-on to a club event?
You have very valuable knowledge that people who are interested in the same hobby would greatly benefit from. It could also be the springing point of something profitable, if you wanted it to be so. Also, I believe it would give the club a lot of credit. I would certainly make an effort to attend.
Just an idea.
Pietro

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PostPosted: 08 Jan 2010, 17:59 
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The whole idea of building this gun was to get a design that anybody could make, and produce a gun that would perform along with the best off the rack products. As far as I am concerned, it won't be a "success" unless other people make similar guns.

I'm amenable to the idea of a workshop at a club meeting. Of course, it would have to be after the Nationals. That would give me time to shake-down/trouble shoot the gun too. (I have yet to take it into the water and shoot anything with it, but hope to do so in coming days - but I have yet to have much success even seeing size pinkies this season)

Ric

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PostPosted: 09 Jan 2010, 09:26 
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looking forward to it ... I'm sure there are people challenging themselves to build their first rail gun (some threads on the forum suggest that) and others might just be interested.
All the best in the water and at the nationals

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PostPosted: 09 Jan 2010, 16:51 
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Components for the Southern Speargun
I’ll document the process of building the gun, but won’t try to do it in one hit, as the document would be too long. I’ll do it bit by bit. For starters I will list the components.

Spear
I purchased a 7 millimetre diameter stainless steel spear. The spear was 1.3 metres in length, but anything within 10 centimetres of this length would have been OK. I got a spear with rounded bridle slots, so as to reduce wear on the soft bridles.

I got my spear from Legendary Spearfishing Supplies, but other spearfishing supplies should be able to provide.

I got a few dollars change from $100

Spear release mechanism
I purchased a Picasso shot engine

I got the mechanism from Legendary Spearfishing Supplies, but other spearfishing supplies should be able to provide.

It set me back about $60

Timber
I went to the “interior timber” section of the nearest Bunnings. There was an area devoted to mouldings, which were labelled “DAR” (which means “dressed all round”). I went to the part selling “hardwood” which was comprised almost completely of “Tasmanian Oak”

There is no actual “Tasmanian Oak” tree. The timber can come from a variety of species, and consequently can vary in colour and grain pattern. Looking closely, som of it was pinkish and had little discernable grain in it. Another piece had a lovely, if subtle, brindle appearance. Seems to me that this variation enhances the aesthetics.

I purchased:
• a piece of “square edge 40 x 8 millimetres” 1.8 metres in length
• a piece of “round edge 30 x 8 millimetres” 2.4 metres in length
• a piece of “30 x 18 millimetres” 2.4 metres in length

These were all longer than I needed, but were the next closest thing I could find on the rack. The spare bits were useful when I stuffed-up and had to re-cut the bit. If I had have gone to a specialist timber supplier who cuts to length, I may have been able to shave the price a little (perhaps).

I went through the racks and only purchased pieces that were dead straight, and were clear of knots or splits.

The wood set me back about $40.

It may be possible to save money by using pine mouldings instead of Tasmanian Oak.

Adhesive
I purchased a 125 gram bottle of polyurethane glue. I selected “Vise” brand as it was the cheapest. It cost $6.
Surface coating
I like to use “Estapol” two pot floor varnish, and I had some waiting in the cupboard. Any other varnish will do fine.

Stainless fastenings
I purchased
• two 10 x 3/4 countersunk (CS) HD self tappers (shorter, ½ inch, would be better still)
• four 6 x 1, countersunk (CS), HD self tappers
• one eyebolt, nut and washer, 6 x 40 millimetres

I got these in Bunnings, where I had to pay about $24. I had to purchase packages containing more screws than I needed. It might be possible to shave costs by going to a specialist supplier, and only purchasing the exact number needed.
Rubber
I used 16 millimetre diameter rubber. I wanted a 3.5 stretch for the 1 metre stock, so I purchased 57 centimetres.

I got the mechanism from Legendary Spearfishing Supplies, but other spearfishing supplies should be able to provide.

I don’t remember what it cost me

Cordage
I purchased five metres of 2 millimetre spectra cord.

I got mine from the local yatching/sailing shop, but I imagine that something similar could be easily obtained from a spearfishing supply shop.

At a pinch, 2.5 millimetre Venetian blind cord could be used.


That’s it for materials.

Ric

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PostPosted: 09 Jan 2010, 19:37 
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3 species go by the name tassie oak, Messmate, mountain ash and and alpine ash. In Victoria we call these Victorian ash. They all make nice guns but I wouldn't suggest them for beginning woodworkers because of there tendency to "break out" . This is what happens as tool exits the back of the piece and breaks away fibres from around the edge of the cut.
If your going to use this timber make sure your tools are sharp and the piece you are machining/cutting is well supported with a piece of timber underneath to cut into rather than just having it hanging over the bench or in a vice.

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PostPosted: 11 Jan 2010, 12:37 
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Thanks Greg, some useful information.

I thought that "Vic ash" was Mountain Ash (E. regnans - if my memory serves me right). Do you have the scientific names of the other species?

The "Tassy Oak" you buy at Bunnings, is bloody hard stuff, and hard to work. Takes a bit of effort to shape it. This is regardless of whatever breed sold under that name. You can see differences in the timber if you look - different colours and grain patterns.

However, the way I designed this gun, using pre-cut mouldings, only a limited amount of work needs to be done on the actual piece of wood, mainly minimal cross-cutting and drilling, so I wouldn't worry too much about how hard this stuff is to work. It can be satisfactorily shaped with a rasp and 80 grit sand paper.

Having said that, I see no reason not to use radiata pine mouldings instead, which is cheaper, and easier to work. I would be a little cautious about using it for long thin stocks though.

Ric

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PostPosted: 11 Jan 2010, 12:41 
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Building the Southern Speargun

Some info on the actual construction.

The stock is to be laminated, with the 30mm x 18 mm as the centre laminate, with the 30mm x 8mm “D” shaped strips down either side.

Cutting to length
The first act was to dock-off the 30 x 18 to 1.1 metre.

After cutting to length, I decided which side was be the top, and which end would be the muzzle. I marked them with a pencil to prevent any confusion later.

Spear guide slots
Before gluing, I needed to cut some recesses in the top of the rectangular piece. These recesses are to take the spear guides.

I cut five recesses. The front spear guide would be not far behind the eye-bolt in the muzzle. The rear spear guide sits just under, and very slightly behind the front slot in the spear (which takes the rubber bridle). The spear guides in between are equally spaced apart.

I used the saw to cut the edges of the recesses, which were 30 millimetres apart. The cuts extended down 4 millimetres. I used the rasp to take out the unwanted wood between the saw cuts, leaving a square edged “U”-shaped recess. I took care to keep surfaces as flat and square as possible.

Also, while I was doing this, I also cut a 5 millimetre cross wise slot for the eye-bolt in the muzzle. This slot was 50 millimetres back from the front tip of the gun.
Laminating the stock
The next step was to laminate the main stock.

I cut two lengths from the “D”-shaped round edge 30 x 8 millimetres strips. The lengths needed to be 50 millimetres shorter than the stock centre-piece, that is, 1.050 metre.

On the rear end of the rectangular centre laminate, I marked lines 50 mm from the end. These lines indicated the area which would eventually mate with the handle, and didn’t need any “D” shaped strip covering them.

I glued the “D” shaped strips onto the rectangular centre-piece. Its best to glue-up the strips one at a time. This takes longer than doing both at once, but usually results in a more accurate outcome.

The stock needs to be dead straight, and the way the gluing is done has an impact on this. I use a straight form, which started life as a square aluminium fence post, but any straight thing will do. I have used the top of the back gate of my ute.

Before placing the strips together, I laid the rectangular centre laminate on a flat surface. I covered its side with polyurethane glue (except for the rear 50 mm) and smoothed out the glue using an icy-pole stick. The idea is to ensure total coverage of the surface to be glued.

I laid one of the “D”-shaped strips on top of the glue. I took care to check that the edges of the two strips were flush.

To get the neatest join, the two pieces of wood need to be held close together. I use wood workers clamps, but there are cheaper (if not so convenient) options. You can lay lead weights on top of the two pieces of wood. Another approach is the “Spanish windlass” where you loop a piece of cord around the wood and the forms, then put a stick into the loop and twist it up tight. Another bit of string on the stick will make sure it remains twisted and keeps on the pressure.

When the glue had set hard (overnight), I unclamped the wood, turned it over and glued on the second “D”-shaped piece to the other side.

Cleaning up
Once the glue has set, there were be messy bits over the sides of the stock, and in the spear guide slots. I cleaned this away as best I could can, using sandpaper, or a chisel (if you don’t have a chisel, a screw driver will do at a pinch).

Spear guides
In the final gun, the spear rests in spear guides. These keep the spear running straight, and reduce spear whip. The result is a more accurate spear.

The spear guides sit up above the stock. They have a groove running in the top of them in which the spear sits. The bottom of the groove, that is, the level of the bottom of the spear (when its in the gun) is 2 to 3 millimetres above the level of the top of the stock. The tops of the sides of the guides should not be so high as to foul the rubber bridles and shooting line when the gun is fired, that is, the groove in the guide should be about 3 millimetres deep.

The guides are cut from left over pieces of the rectangular 30 x 18. They are cut just long enough to fit into the recesses cut in the top of the stock.

Precisely, the bit of wood that make the guides should be 30 millimetres long (to match the length of the recesses in the top of the stock). They should be 4 millimetres deep (to match the depth of the recess) plus 3 millimetres (clearance between the spear and the top of the stock), plus another 3 millimetres (to allow for the sides of the guides coming halfway up the spear). That is, 10 millimetres. I made mine a tad thicker to allow for mistakes and cut them off a little later on. Since the guides are cut from the same wood as the centre laminate in the stock, that thickness should be right.

I cut a groove along the centre of the top of the guides using the side of the rasp. I neatened the groove with sand paper wrapped around a drill bit. The grooves were about 3 millimetres deep and 4 millimetres wide. I made the groove in the front guide a little bit wider to help the spear stay in it when the gun is tilted on an angle. I rounded the outside edges neatly.

I put some glue in the recesses on the top of the stock, popped in the guides, and clamped them down till the glue set.

Later on, when I had done the handle and had fitted the trigger mechanism, I placed a spear in the gun, and found the grooves would be more level if I took the sandpaper and drill, and sanded a couple down a bit more.

“Brett’s” muzzle hole and slot
The “Brett’s” muzzle features a stainless steel eye bolt as the final spear guide, with the shank of the eye bolt extending down through the stock.

When the first cuts for the spear guides were being done, I also made a narrower cut to house the bottom edge of the eye bolt. This cut was 5 millimetres wide (same thickness as the eye bolt) and was 50 millimetres from the front tip of the gun.

Slap bang in the middle of the narrow recess in the centre laminate, I drilled a 5 mm hole vertically through. This snugly fitted the shank of the eye bolt. However without further attention, the eye still sat too high. I turned the rasp on its side, and used the thin edge to remove a bit of wood from the “D”-shaped side plates.

I dry -fitted the eye bolt to ensure it sat at the right depth (which is when the spear, in the loaded gun, sits in the middle of the eye).

Drilling the rubber hole
The Southern Speargun features a “dropped” rubber. That is, the rubber goes through a hole in the stock, and is not on the same plane as the spear.

I measured back 20 mm from the front of the stock. In the middle of the side, I marked a cross – which was to be the centre of the rubber hole. I did the same for the other side.

Using a small drill (2mm or something similar) I drilled a pilot hole. I first drilled in about half way from one side, then drilled in from the other side. (If you are moderately accurate, the holes will join and be at right angles to the side of the stock.) I took a 16 mm spade drill, placed its point on the pilot hole, and drilled halfway. I turned over the stock, and drilled in from the other side till the drill broke through. To get the best result, be gentle.

I used the round rasp to take the corner of the rear end of the hole, and then used 80 grit sandpaper, rolled-up to make a tube.

Rounding the front
I took the rasp, and rounded the edges on the front end. I did each side first, then rounded the corners. I used 80 grit sandpaper to smooth it down. I also cut a vertical slot to take the shooting line.

Shooting line hole
I measured back approximately 100 millimetres from the front tip of the stock, and then marked in the middle of the stock. I used a square to mark the opposite side. Then I drilled a 4 millimetre hole half way through the stock. Turning it over, I drilled in from the other side, to join the hole. Using a larger drill, not pushing at all hard, I countersunk the edges of the hole, and then sanded over to smooth it.

The next posting will detail the construction of the handle and fitting the shot engine.

If some of this was confusing, I have pics that can be posted.

Ric

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PostPosted: 11 Jan 2010, 15:42 
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Messmate= E. obliqua alpine ash=E. delegatensis mountain ash=E. regnans
To make things more confusing the call messmate "brown topped stringybark" in Tassie. Then to make it more confusing we call E. nitens or shinning gum and E. exocarpa or grey gum Vic ash as well over here. Life would be so much easier if we just stuck to scientific names.
On another note have you ever tried Forstner bits, they leave a very clean hole and you don't need to drill pilot holes, you just go straight through in one go. The hole is nearly as clean as a planed edge. I won't use a spade bit again for anything other than doweling where i want a rough hole for the glue.

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PostPosted: 12 Jan 2010, 11:10 
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Thanks for the info - seems that the names of timber and trees are more complex than fish names. The odd few fish have different names in the water and the market, but this seems to be really common in timber.

I suppose it just takes lots of experience and familiarity to be able to recognise a timber.

With Tas Oak I purchase in Bunnings, there seem to be two main types - one has a fine straight grain and is pinkish in colour, and the other has darker brown streaks in it, and is also not so hard. Sometimes you get a timber that is whiter too, with a fine straight grain.

I have Forstner bits (well, Carbatech forstner-style) bits, and they do make a lovely clean cut, and are particularly good if you want to make a hole to take plugs, as the hole is perfectly circular.

An advantage of spade drills is that they will follow a pilot hole when you use a hand held drill, and the hole can come in from either side of the wood. When I use forstner bits, I use them in the drill press, and have to have a piece of wood that is dead square for them to come out the same as they go in.

For the Southern Speargun, I wanted to minimise the tools used, and have them as cheap as possible. I managed to get my spade bits in a $2 shop, where they were really cheap. The blades are not symetrical, blunt quickly and may differ as much as 1 or 2 millimetres from the widths marked on them. But for the purposes of the job, are the satisfactory and very cost-effective.

Ric

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PostPosted: 12 Jan 2010, 11:20 
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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
handle-piece with mortise.JPG [ 30.47 KiB | Viewed 11495 times ]
File comment: After the top side plates have been attached, the handle is built up by gluing on other pieces
building up handle.JPG
building up handle.JPG [ 41.45 KiB | Viewed 11498 times ]

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Ric Fallu started spearfishing in Pt Phillip in the early 1960s, and never really stopped
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PostPosted: 16 Jan 2010, 17:22 
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Joined: 23 Nov 2007, 12:20
Posts: 305
Location: Melbourne/Sth Gippsland
I took the Southern Speargun for its initial swim this morning.

In the shallows, I noted that it had negative buoyancy. It sank to the bottom, and hung, handle-up. There is no need to add ballast.

When I picked it up, I noted that it was a bit front-heavy. No doubt, the stainless steel eye bolt in the muzzle contributed to this. A gun being a little front-heavy is not necessarily a bad thing. Holding it at arm’s length for the duration of a dive was not a problem in the slightest.

Loading was not a problem. I put the butt on my belly, and loaded to the first notch. Then I lifted it to my chest to load to the last notch. I could probably do it to the second notch in one go, but why make things harder than they have to be?

The shooting line needed to be arranged during loading. If it was not, it tended to lie in the spear alignment grooves, and put the spear a little off to one side. I pushed it to one side, outside of the spear guides. If the line was appropriately arranged during loading, it stayed where it was supposed to be.

Swimming and diving with the gun was quite easy. The “blocky” shape of the trigger guard did not prevent leaving my index finger outside of the trigger hole (until a fish was seen that is).

The small simple handle did not give quite as much purchase as one with a second finger notch, and a bit more ergonomic modelling, but it was more than adequate.

The gun was not hard to swing in the water, and its narrow stock did not create too much water resistance. In fact, it was quite easy to manoeuvre.

There were pinkies around, and they came in readily to my berley, but whilst some might have just made minimum legal size, none were large enough to justify a shot. I had to look for other species to shoot.

While I was lying on the bottom watching pinkies, a school of King George Whiting came in. I normally find KGW hard to hit, what with them being a long and slender shape. I lined one up, and fired. I got it dead centre, just behind the gills. This was an accurate shot. The gun’s first blood was not much of a trophy fish, but it did prove the gun could be accurate.

A little further on, I spied a flathead lying on the bottom. I swam around to shoot it head on (that way the fish swims up the spear, not away off it). I hit it OK, but the shot was about 15 to 20 millimetres to the right of where I thought I aimed. More than likely this was my fault, and not the fault of the gun.

A little later I encountered another school of whiting: not real large, but legal size. These fish were not to keen on coming in real close (despite my doing a bust). Eventually, I let off a shot, with the fish maybe two metres from the end of the gun. I hit the whiting just behind the gills and it was strung on the shooting line. However, it tore off and swam slowly away. I chased after it, but lost it around a ledge.

So, the gun is easy to load, comfortable to carry, and is reasonably accurate. It is easy to swing. The viz wasn’t really good enough to assess its long distance accuracy. Attention needs to be paid to how the shooting line lays along the spear guides during loading.

Ric

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Ric Fallu started spearfishing in Pt Phillip in the early 1960s, and never really stopped


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