Mick B1 | 14/09/2018 19:04:26 |
2444 forum posts 139 photos | I made this from Richard Stewart and Donald Heyes book 'Scale Model Cannon' as one of the most realistic of the selection in the book. It's still awaiting a number of rope-eyes and I'm debating whether to try building a section of dummy hull with rope tackle etc. I used oak stripwood from B&Q instead of the BDMS flats the authors recommended. It's rather small - about 5" OAL, and another thing I'm thinking of is building it again at double scale. I tried bluing it with a paste similar to the G96 product available in gunshops. Whether the stuff was too old (it had dried hard and I added distilled water to try and revive it) or the mild steel was unsuitable, it didn't take well. I went black quick enough, but adhesion was poor to nonexistent, so I scotchbrited and WD40'd it all off again. Might try again when I can persuade myself to buy some proper G96...
Edited By Mick B1 on 14/09/2018 19:06:46 |
duncan webster | 14/09/2018 20:14:01 |
5307 forum posts 83 photos | I have a recipe given to me 40 years ago for a witch's brew containing sodium nitrite and caustic soda (from memory). This is to be made into a strong solution which boils at considerably more then 100C. Sounds like a recipe for disaster to me which is why I've never tried it but if you're interested let me know and I'll try to find it. I have a vague idea where it is! If you do decide to try it, use a bit of scrap first, it would be a shame to mess up all your excellent work. I'm assuming it is steel, if cast iron all bets are off. |
Vic | 14/09/2018 20:20:16 |
3453 forum posts 23 photos | I’ve found Sandblasting to be a good base for blacking, you get a really deep black on steel. |
Jeff Dayman | 14/09/2018 20:43:17 |
2356 forum posts 47 photos | Mick B1 - I think it looks just great as is. Nice job! |
Mick B1 | 14/09/2018 20:45:21 |
2444 forum posts 139 photos | Posted by duncan webster on 14/09/2018 20:14:01:
I have a recipe given to me 40 years ago for a witch's brew containing sodium nitrite and caustic soda (from memory). .... I'm assuming it is steel, if cast iron all bets are off. By 'eck - it's a non-shooter, but at first I wondered if you were suggesting some sort of fiendish propellant... Yes, it's plain BDMS, allegedly EN1a, though it's not quite as free- and clean-machining as some I've had.
As for Vic's sandblasting - isn't that likely to give a matt finish? The other cannon in my album was also turned from BDMS, washed in near-boiling detergent water immediately prior to applying G96 paste, then washed again, oiled and polished. That produced a glossy finish that's lasted 16 years with little maintenance. |
duncan webster | 14/09/2018 21:07:47 |
5307 forum posts 83 photos | found the brew on the interweb, as I said liquids boiling at 140C. I wouldn't try this on the kitchen stove, if it works let us know**LINK** |
Clive B | 15/09/2018 02:57:19 |
46 forum posts 21 photos | Nice model Mick. A carronade is on my list of things I'd like to make. Where are you getting the rope eyes from? Clive
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Mick B1 | 15/09/2018 09:16:19 |
2444 forum posts 139 photos | Posted by Clive B on 15/09/2018 02:57:19:
Nice model Mick. A carronade is on my list of things I'd like to make. Where are you getting the rope eyes from? Clive Let's see if they're any b100dy good first... |
Eric Cox | 15/09/2018 10:14:37 |
![]() 557 forum posts 38 photos | How did you fit the pivot block on the under side of the barrel.
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Mick B1 | 15/09/2018 12:06:43 |
2444 forum posts 139 photos | Posted by Eric Cox on 15/09/2018 10:14:37:
How did you fit the pivot block on the under side of the barrel.
Threaded it 5/16" x 32 x approx. 6mm deep, then did part-turns of the die on the spigot till the block lined up. |
Brian H | 15/09/2018 12:50:42 |
![]() 2312 forum posts 112 photos | There are drawings of a long 12 pounder & carriage and a carronade & carriage in C Nepean Longbridges book " The Anatomy of Nelsons Ships". There are also full details of the ships construction. Brian |
Brian H | 15/09/2018 12:50:46 |
![]() 2312 forum posts 112 photos | There are drawings of a long 12 pounder & carriage and a carronade & carriage in C Nepean Longridges book " The Anatomy of Nelsons Ships". There are also full details of the ships construction. Brian Edited By BDH on 15/09/2018 12:51:33 |
Glyn Davies | 15/09/2018 13:18:50 |
146 forum posts 56 photos | As regards bluing the metal - I think you'll find that the sodium nitrate is now classed as an explosive precursor so that, for our safety, the freedom we once had to buy it has been removed. An option is to rust blue it. You can still buy ammonium chloride (sal ammoniac) on ebay and if you dissolve 2 grammes into 100 grammes of water, you have an effective rust bluing solution. I'd try on scrap steel first and see if you like the result. Method is to swab the solution sparingly onto the degreased steel and leave supported above a dish of water for a couple of hours until a light grey/brown rust forms on the surface. Then immerse the item in boiling water for a few minutes, let it cool and rub off the loose fine rust with 0000 wire wool. Repeat the swabbing, rusting, boiling and wire wooling five or six times until the metal looks a sort of grey colour after the final wire wooling. The last step is to rub in some linseed oil, which will give some corrosion protection and turn the colour from grey to blue/black. You can actually use sodium chloride at a pinch(!) in place of ammonium chloride but the process might take longer to get to a good blue.
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Ian S C | 15/09/2018 14:38:47 |
![]() 7468 forum posts 230 photos | I hope the Oak doesn't attack the mild steel. At our MenzShed one of the guys thought he had the answer for storing some black smith drills (1/2" shank), drilled some holes in a block of wood, put the drills in, and the next week the drill shanks had rusted and had to be forced out of the holes, not too much damage, but what a mess, I made a new rack from steel. I'v only ever used heat for bluing steel. Ian S C |
Neil Wyatt | 15/09/2018 15:07:50 |
![]() 19226 forum posts 749 photos 86 articles | Excellent model, well done Mick. |
roy entwistle | 15/09/2018 15:24:41 |
1716 forum posts | I would agree with Ian S C regarding the use of oak Roy |
Mick B1 | 15/09/2018 16:49:42 |
2444 forum posts 139 photos | Ian and Roy, Ain't no rust to speak of on me 24-pounder trunnions after 16 years in contact with oak:- I think the trunnion caps are 9/16" silver steel, and I may have varnished the oak before laying in the barrel - but I think that's unlikely as I was looking for a close running fit and reckon I cut the mount with a 9/16" slot drill, but it's all a bit vague now... Oh yes, and I think I've got the grain in the oak running the wrong way - should be horizontal. And thanks for kind words. Edited By Mick B1 on 15/09/2018 16:52:30 |
Robert Atkinson 2 | 15/09/2018 19:50:29 |
![]() 1891 forum posts 37 photos | Sodium nitrate isn't on the EPP list, see https://www.gov.uk/government/publications/licensing-for-home-users-of-explosives-precursors/licensing-for-home-users-of-poisons-and-explosive-precursors So you can buy it OK . Try ebay. Robert. |
duncan webster | 15/09/2018 22:20:34 |
5307 forum posts 83 photos | Looking at ebay, sodium nitrate is quite expensive, potassium nitrate is quite a bit cheaper. It is used in curing ham amongst other things. No idea whether it would work as well, perhaps some chemist out there can comment |
Mick B1 | 16/09/2018 07:08:27 |
2444 forum posts 139 photos | I think buying saltpetre to go with a model blackpowder cannon might generate questions? I'd imagine if it were set up to fire, it would perform much like one of those small flintlock or percussion pocket pistols, say like an original Deringer. Any road up, family are saying they like it as it is, as have some on here - so for the time being I'll not be following up on bluing/blacking. |
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