9 Pound Naval Cannon 1786 by AON - FINISHED - 1:12 scale

[AON]

I will be getting back to my slow progressing scratch build of HMS Bellerophon with a goal to complete all the frames before next summer... but after a summer of home renovations, grass cutting, fishing, and a little carving, I found myself being drawn to something a couple members of our local club (Model Shipwrights of Niagara) brought to one of our monthly meetings earlier in the year (before the summer).

This project was started on 24 October 2018.

[AON]

One had brought in a naval gun assembled from a kit and the other had 3D printed various size naval cannon barrels at his local library.  I found this fascinating and now had an itch to build my own naval gun.  Our local library posted a notice of a 90 minute compulsory course (on the evening of 20 November) to allow library card holders to use their 3D printer, so I signed up.  A search on their website revealed they allow a 8Mb maximum size STL file of any non-copyrighted 3D image.  The build area size is 230 mm long (9") x 150mm wide (5.9") x 130mm high (5.1").  They have a variety of colours and black is an option.

 

I started my research on this forum, and concluded with a wider search on the internet and books in my personal library.  I decided on a 9 Pound Naval Cannon that would be found on the quarterdeck or forecastle of HMS Bellerophon (1768), a 74 gun Man of War.  Having gathered all the data I could, I made a full size model using Autodesk Inventor.  I would rescale it to 1 inch = 12 inches (1:12) later.  I settled on this scale because the dimensions of the 9 Pdr fits the 3D printer build area size at 1:12.

 

I brought my info to the October meeting of the Model Shipwrights of Niagara and was told by the single member with experience that the 3D printer needs to start the build on a flat surface (so the object doesn't roll away).  This gentleman had made several very small prints in one file (all at once) and oriented his cannons to stand on their flat muzzle.  It was suggested by a well weathered modelling member I might split the cannon in half to create a flat surface to build up from and then glue them together afterwards.  My model was altered and I added six cannon balls (with a flat underside) to add to my display.  The STL file for these items is 7.68Mb in size.  I may need to make changes after I attend the  compulsory 3D printing course.

[AON]

I then created a 2D drawing of the carriage assembly and details using the free downloadable software version of DraftSight. I inserted images and scaled them to full size so I could refer directly to these to create the drawing. This was drawn full size, fitted on 8.5 foot x 11 foot rectangular borders scaled up from the dimensions of a standard A size sheet of paper (8.5" x 11").  I added a cannon ball rack as an afterthought.  Below is a screen shot and a downloadable PDF of the 2 sheet templates on the left.

 

9 Pdr Naval Carriage Dwg (1 of 2) - AON - 25OCT2018.pdf

9 Pdr Naval Carriage Dwg (2 of 2) - AON - 25OCT2018.pdf

Edited February 13, 2019 by AON
reloaded PDF's of drawings as link to second sheet reported as broken

[AON]

While waiting for the 3D printing course I decided to build the carriage assembly. The first thing was to select wood material.  The real carriages were originally made of elm and later this changed to be oak.  As a scaled down version the normal choice would be something with a tighter grain.  Since the wood was getting  painted it really didn't matter what I used but the song "Hearts of Oak" came to mind so I decided to use oak.  I have old oak shipping planks that needed to be cut down to near size on the table saw and then sanded to thickness.

The first items made were the two piece BRACKETS or CHEEKS.  I've found them called by both names.  The pattern was transferred from the plan to the wood using carbon paper and a pencil. I decided to soften the edges by rubbing them with fine sand paper.  This was done to all pieces I made for the carriage.  Although initially cut square, the axle tree and gun barrel trunnion pockets needed to be filed at a very slight angle because the brackets are set at 7°.

[AON]

Next came the FORE and HIND AXLE TREES.  I decided to make each of these in multiple pieces.  The round axles would be made of maple dowels sanded on the lathe to the proper diameter.  I drilled pockets into the oak blocks and later glued (yellow wood glue) the maple rounds into them.  The dowels were purposefully made about 1/4" too long.  After curing overnight I sanded these down to the proper projected length.

Note that both ends of the rectangular block parts are rounded to the pockets prior to gluing the dowels in place.

 

I will not be adding metal bands at the end of the rounded dowel parts as to my understanding this was a feature added later in time.

The BOLSTER was simply a rectangular block of wood... easily the simplest part to be made!

[AON]

The third pieces to make were the HIND and FORE TRUCKS (or wheels).  These were also made of maple dowels of diameters just larger than required and sanded down on the lathe. I sanded down a length adequate for two trucks, then scored the proper widths leaving a 1/4" gap between each truck.  I drilled the axle hole through on the drill press, and lastly cut between the 1/4" gap with my band saw.  The individual trucks were then sanded to the score marks.

 

I chose to make my TRUCKS in one piece as I understand the bolted two layer/four piece sandwiched Truck with grains running at 90° was a feature that followed at a later time.  I did not use metal trucks as they were never used on the wooden decks of ships since they would cause too much damage to the deck.

[AON]

Then came the TRANSOM.  This item sits under the cannon Trunnion pockets, between the Brackets and directly on top of the Fore Truck set at an angle leaning aft.  The sides mating to the Brackets (set at 7°) needed to be sanded slightly at opposing angles to butt properly.

[AON]

The last wooden pieces were the STOOL BED and QUOIN (wedge) used to set the firing angle of the gun.  These were the toughest parts to research as there seems to be quite a bit of conflicting information. Some show their mating surfaces to be flat.  Others show a keyseat or pocket in the Stool Bed and a key extending below the Quoin to fit into it.  Yet, others show the top of the Stool Bed and underside of the Quoin to have engaging sideways racks of teeth to lock the Quoin in place (keep the Quoin from slipping).  Some show multiple stacked wedges being used. Some have a handle on the Quoin whereas others do not.  The Stool Bed on some were square sided whereas others were tapered on the sides.

 

I chose to taper the sides of the STOOL BED and simplify the engagement with a simple keyseat and key.

 

The keyseat was sawn with a fine 24 tooth saw, chiselled out with mini a chisel and finally filed to shape.

[AON]

The QUOIN was made similarly with the key fitted to slide in the keyseat.

[AON]

The QUOIN HANDLE was made of maple dowelling, filed and sanded to shape while mounted in the drill press chuck.  A pocket was drilled in the Quoin with the nearest sized number drill I had and the Handle was filed once again to fit quite snuggly in the hole and so is one of the few pieces not glued.

[AON]

Here is the final dry fitted assembly.  The Transom is held in place and kept from falling with a small temporary shelf board clamped to one Bracket.  It requires a few more holes to be drilled in the brackets before I start on the hardware.

[Osmosis]

Nice work so far. These are a lot of fun aren't they. I built the kit from model shipways in 1/24 scale and just had to build the carriage from scratch as theirs was not quite up to snuff. Can't wait to see yours finished. Keep the updates coming please.

 

Regards

 

Edited November 6, 2018 by Osmosis

[Tigersteve]

Very nice. 

Steve

[AON]

Prior to this, I decided to put my thoughts down on paper for the display case.  The topic of our October Model Shipwrights of Niagara club meeting happened to be on building display cases.  If you are interested in downloading a very informative PDF of this presentation go to the blog page of our website      ( https://modelshipwrightsofniagara.weebly.com/ )  and search for October 2018.

 

I copied the top view of my carriage and added a crude tracing of the cannon to get the overall size so I could pick a display mounting base size.  To this I added the cannon ball rack to get the full effect.  6" x 10" seemed perfect. The inside of the Plexiglas case would fit over this.  I decided the model would be displayed as if it were on a ship's deck.  I drew the planks at 12" width, added a few staggered butt joints and the treenails.  Then I created the information plates and decided their placement.  I have yet to decide if they will be engraved brass or white on black lamacoid labels with bevelled edges... or something else.  I've also played with the text quite a few times and am still not quite happy. Less is usually more but sometimes not enough.

9 Pdr Naval Carriage Display Board Size Dwg - AON - 28OCT2018.pdf

[AON]

I have a sheet of 1/2" maple finished plywood that I can make the mounting base from.  The planks can be scored in and the joints darkened with a lead pencil.  The treenails holes can be drilled and filled with 5/32" diameter dowelling.

 

The mounting base will be placed on a sub plate that will create a ledge for the Plexiglas case to rest on.  The Plexiglas will be pinned to the mounting base so it doesn't separate from the base if picked up by the glass.  The outside of the sub plate may be completed with finish moulding.

 

My next part to work on was the CANNON BALL RACK.  This was cut out on the scroll saw, sanded and the divots were marked off and drilled in.  I am considering leaving this single piece unpainted as this is how they seemed to be when mounted on deck.

[AON]

I went back to the BRACKETS (CHEEKS) and slightly countersunk three holes in each using a small brad bit.  Then I drilled in the missing bolt holes on the top for the trunnion Cap Square and the bottom for the Fore Axletree support bracket.   This was followed with some light sanding

[AON]

LINCH PINS were made from copper wire.  One end flattened in the vise then filed to shape.  Measured and cut to length and the lead "pin" end was filed round.  The wire was straightened as best as I could and test fitted.  Three of the four wheels needed to be sanded thinner so the pins could be driven into place.

[AON]

Prior to starting the other metal pieces I decided to cut and lightly mark (with a soft HB pencil) the deck plank and treenail layout.

[AON]

I practised with a scrap piece of plywood to assure I had the treenail dowel drilled hole size and the scribed caulking line cut technique correct.  I scribed the line with my Veritus Scriber drawn against a cork backed straight edge held down firmly with one hand.  I then went over the lines with a mini Vee notch chisel to widen the line.   The line was darkened with a sharp HB pencil. The pencil required continuous sharpening to assure it reached the bottom of the notch.

[AON]

I drilled out the holes and cut my treenails from 1/8" diameter dowelling at 1/2" long.  I pushed them into the holes with a dab of yellow wood glue with a small amount projecting above the board.  I cut them flush with my Veritus Flush Cut Saw, wiped the board with a damp cloth and later sanded it all and wiped it once again.  After all of this I needed to run my V chisel through the notch and re-darken the caulk lines with the my pencil.

[AON]

To get a better idea of the size and be able to better determine the display case dimensions I made a mock up of the cannon, mounted it to the carriage and placed everything on the base.

 

I originally thought the case would be 5-1/2" tall (measured from the open bottom lip to the inside top of the case) but this mock up had me drop the 1/2". 

 

I did some pricing.  To purchase an adequate supply of 3mm (1/8") thick clear acrylic sheet (Plexiglas), some Plastic solvent glue (Weld-on #4SC), an applicator (20cc syringe with 16 gauge blunt needle), and acrylic cutting tool would cost upwards of $251 CDN plus taxes and shipping.  I asked for a quote from people who do this for a living and all said and done it was $200.56 CDN including taxes and my picking it up.  This is the first cover I will have ever had and I fear it will be prettier than my model.

 

I ordered my Plexiglas from a local company named Plastruct Polyzone in Vineland, Ontario.  They have my base to fit the case to and called to let me know my case was a total of 1/32" out of square from short end to short end (at 1/64" skew per end).   The long sides were parallel.  This company did work for the firm I was last employed with, and those items were to four and five decimal place tolerances, so I know they are that good... but my table saw is not.  They notified me the case would be ready for pickup on the 14th of November (shy one day of two weeks away as today is 1 Nov).

Just received another e-mail the following day (Friday the 2nd of Nov) that the case is ready for pickup.  I cannot get there until Monday.

[AON]

Now was time to yellow wood glue the carriage together, wipe it all down with TACK CLOTH to remove all the dust particles, and finally prime the wood with GESSO SURFACE PREP.  This is a white water base coating that dries to the touch quite quickly, but I let it sit over night.

Some of the grains popped out a bit (swollen) and a few feathery bit poked out.  I like the look of the wood grain but the feathery bits need to be removed.

 

As for the finish coat colour of the carriage, I've seen them painted grey, red, black, brown, and left bare. Mine was to be YELLOW OCHRE in colour as I've read that this was the original colour of the ship's gun carriages for the time (ref: https://www.dailymail.co.uk/news/article-2583165/Nelsons-flagship-HMS-Victory-true-colours-blue-deck-none-hideous-orange.html).  The very first photo at the beginning of this build and the following image are the proof.  Unfortunately I found Yellow Ochre to be too brown for me, and so after some testing I went with Naples Yellow Hue which is slightly less brown and more yellow.  I used Liquidtex Professional Heavy Body Acrylic series 2 paint.

 

All fittings will be black and the TRUCKS (wheels) will be left bare.

[mtaylor]

Nice work, Alan.  These large scale cannon builds are usually quick and very satisfying. 

[AON]

Yes, just what the doctor ordered to get me back in the groove!

[AON]

Now was the time to tackle the fittings.  There are a number of eyebolts and a couple with rings: Train Tackle Eye, Gun Tackle Eye, Gun Tackle Loop and Breeching Ringbolt.  These are all rather large diameter bolts  ( 1"  to 1-1/4" diameter) and gave me some grief to make.  After numerous attempts I finally stumbled on a method that worked for me.  I used an Allen Key (of a size similar to the inside diameter of the eye) as a mandrel to wrap the copper wire around. To start the end was clamped in place with smooth jaw pliers as I pulled and wound the wire through slightly more than 360°.  The wire loop (eye part) was then squeeze tight against the key with the same pliers to make it a snug fit.  The loop (eye part) was than squeeze snuggly against itself.  The standing end (bolt part not, the eye part) was straightened out and the overlap of the eye was snipped of.  The eye was knocked together flat with light taps of a hammer on an anvil and then any gap was closed with a couple lateral taps with the hammer.  The round eye shape was adjusted and the bolt was snipped off after filing a couple notches in it to allow something for the glue to gab to when inserted in the hole.  The ring was made in a similar fashion with the finished ring being assembled to the eye before it's loop was closed up.

[AON]

The FORE AXLETREE STAY was made of copper plate.  The actual plate measures about 3/8" (9.5mm) thick or 0.04" (1mm) to scale.  After hunting around my workshop I found some copper water tube that had a wall thickness of 0.032"... close enough!  I needed to slice it open with a hacksaw, and flatten it out with a hammer on the anvil to make the plate.  I started by making a paper template to fit on the model to determine the lengths required.  Then cut it to size with a cut off disc on my Dremel tool, filed off the burrs, bent and drilled holes in the Stays.

[AON]

The next item to make was the CAPSQUARE using yet another flattened out copper tube material and new paper templates.  The plates required a number of attempts at bending.  The slot at the hinged end was cut with my Dremel tool and cutoff disk, then opened with a drill bit to fit the CAPSQUARE EYEBOLT (a simple piece of wire with a bent U at one end to make a staple).  The hinge pin was then roll/clamped in place.   My second and third Capsquare turned into scrap and so there was a fourth before it was done.

Finally the Capsquare Joint Bolt slots were drilled and filed.

[AON]

All these pieces were dry fitted to the carriage to give me a feel for the final look... and I like it so far.  Two eye shafts needed adjustment so the eye sat properly.  The simulated bolt heads are solid brass 1/2" x 18 gauge escutcheon pins bought at the local Canadian Tire store, hardware section.  I cut the length short to about 1/8" and intend to glue these in place after blackening.  I need to drill two new holes for the Fore Axletree Stays and the two missing holes for the Capsquare Locking Key Chain Rings.

[AON]

The CAPSQUARE JOINT BOLT was made out of plate, cut and filed to fit the slot in the Capsquare, and a hole drilled through to accommodate the Locking Key.  The chain was purchased from Michael's, a local craft store in St. Catharines, Ontario (a 20 minute drive).  It is from an 18" long black jewellery necklace collar.  The Locking Key was made twice.  I didn't like the first attempt and so, after sleeping on it, I made a more proper Locking Key.  My copper plate material was too thin so I folded it over to get double the thickness, filed it to shape and drilled the hole to which the chain will attach.

[AON]

All metal pieces are made and need to be blackened.

 

The clear acrylic display case cover and my mounting plate were picked up today.  The case looks wonderful but the fit is questionable.  The case fits very well to the long sides but is too sloppy (too large a gap) on the short sides.  This is likely my fault for not sanding the ends perfectly square to start with.  The clearance measures 0.108" (2.7mm) whereas on the long sides it is 0.0005" (0.01mm).  My solution is to sand both short ends square (as these are slightly out of square) and apply a 1/32" (0.8mm) maple wood veneer over the end to decrease the gap and snug up the fit with the acrylic cover.  I should probably do the long sides also so the cut edges look finished.

 

Went out and bought a $4 pair of door hinges.  Cut one in half and took the pin halves out.  I will use these as the locking pins for the acrylic cover.  This pin will keep the cover from popping off if the display case is picked up by the cover.  Thank goodness I went to last months club meeting to learn this pinning trick.