drduncan

No I hadn't seen it - an interesting approach. Thanks. D

Today’s progress on the BG 3521 st… The bus bars were glued in place and then wipers from thin PB wire soldered in place. Then an 8 pin dcc socket connected up. Next job will be fit and quarter the wheels and then fit coupling rods. And test - and hope everything works as it should! Duncan

More progress on the Broad Gauge 3521saddle tank. I’ve now fitted the motor and gearbox - a high level box and a Mashima 1220. I also soldered the rocking trailing axle bushes to the pivot bar. I have also been given thought to pick ups. Naturally I thought about this after I printed out the chassis, but that is what files and dental burrs are for! It struck me that the top of the gap between the inner and outer frames might be worth a shot, so I filed and ground a slot to take a bus bar on each side on to which phosphor bronze wire scraper pick up will be soldered. After trying some 0.8mm brass rod for the bus bars, I decided on .5mm. I’ll be able to incorporate the groves for the bus bars and pickups on the CAD for the BG 3521 0-4-4t which is coming in behind the saddle tank version in the CAD queue. Next job is to increase the width of the footplate by 0.25mm each side and move the balance out by the same amount as the clearance in the rocking (from) coupled axle is non existent! And then reprint with better supports to hopefully cure the poor printing of the front sandboxes and rear of the lower boiler.

The Wessex symbol is a red wyvern or there is the medieval https://commons.m.wikimedia.org/wiki/File:FlagOfWessex.svg#mw-jump-to-license Mercia is a yellow saltire on a blue background, again a medieval creation. Given Victorian interest in antiquarianism any of these might have been co-opted by the M&WJR. The wyvren might have been seem as a bit too Welsh (and Arthurian) for taste, but on the plus side both medieval coats of arms share a blue background which might allow the company to play around with. Duncan

Yes but you’re 2mm so build volume is a fraction of the problem faced by us 4mm types… I mean, I could print 2mm Dreadnoughts on my printer (probably) …. But I’m not going to design them while I have so much Broad Gauge to sort out!

@corneliuslundie You mean like this… Not the best lighting or photo I admit, but it is a GWR broad gauge 6w composite (yes I know it’s missing the middle axle). In standard gauge days these were diag U20. This was done on a Photon mono so 31footers or less are no more difficult in terms of cad techniques than a wagon. There’s just a lot more mouse clicks… The biggest problem is build plate size/volume. You need something like a Saturn or mono x for short bogie coaches c40-45’ (although I did manage to print a 48’6” GWR E19 brake tri comp as a single item (sans roof) on a Form 2 but that was almost printed on its end to fit it in the build volume to see if it was even possible). The Anycubic M3 max (approx £900) gives a build plate big enough to print 70 footers in one piece… Dreadnoughts and Concertinas anyone? Duncan

Hi Bill, thanks for the post. That’s fair enough regarding trade secrets. I’ve used a form 2 at work and their standard resins (and had the finance officer scream at me when when ordering more…) but I haven’t used any engineering resins hence my interest. I admit the Formlabs products are very nice but way out of the hobbyist price range - including their resins (which as far as I’m aware are specific to their printers using special chipped containers).

@Schooner is, as usual, being too kind. What he had from me was effectively an accident. When I did the original design there were a lot less parts than his picture showed but I had designed for EM and P4. It was only after I had offered to do some for Louis that I remembered that some people did use OO! So to make it something usable for all 4mm modellers it had to be more kit like than I had hoped. I certainly wouldn’t want to disparage @billbedford ‘s approach. I’m testing his new 3D printed replacements for the brass lost wax couplings he used to do via Eileen’s Emporium. I’m happy to say these are seriously impressive and I’m looking forward to getting them onto my stock. That I think it does show is there things that are at the heart of the 3D printing relationship: The printer The mix of resins used The designer’s preferences @Andy Vincent and I have discussed machines and resin mixes to both strengthen the print and ease post production processing. It can be a highly trial and error process and once the designer had something they think gives the quality they desire it’s only natural to repeat it and avoid doing something that will displease the printer gods! I don’t know what resin mix @billbedford uses (but would love to know) partnered with what printer but this will make a difference as to the art of the possible. Also, we should and can avoid being proscriptive about the designer’s philosophy. 3D printing gives us a lot of options and the ability to effectively print on demand means we don’t have to tie up large sums of money in unsold stock (unless we want to). This, I think, gives space in the market place for a range of small business that may do similar things but in different ways - the customer can then chose the design philosophy that suits them for that given project. No one solution is right but we can all benefit from seeing a range of responses to the same basic design and production problems. Duncan

@MikeTrice There is a small amount of up and down movement in the build plate when grasped. I’ll investigate anti backlash nuts and hue on earth to fit one to the photon mono. D

My mistake, I need 7’ ones

So while trying to sort out distortion at the point closest to the build plate - see @garethashenden thread on the subject - I’ve been working on my broad gauge 3521 saddle tank. I have printed the chassis and I have started a test build to see what is or isn’t working. The fitting if brass top hat bearing for the fixed driven axle worked ok and today I made up full width bearing for the rocking trailing axle and fitted it. The plan is that the motor will sit vertically in the firebox. The footplate has been printed with the lower part of the boiler included so that this can be used to hold the DCC chip. This printed well enough to test fit, but it printed poorly at the rear of the lower boiler and the front sand boxes so some revision is needed. I need to fit the horn blocks to the front driving axle but to do this I’ll have to negotiate the Alan Gibson ordering system to get the 7’6” coupling rods that are needed. I do have two sets of Lancashire Model Supplies variable length rods for planned models of GWR 13 and 34 both in original condition - ordering them was a doddle, just a couple of mouse clicks and done, but unfortunately they don’t do 7’6” rods for a 4 coupled loco. All the best, Duncan

Thanks D

Hi Mike, Thanks for the reply. The FEP seems ok - the photon mono comes pre-fitted in a replacement frame. When you say lead screws what do you mean and any suggestions as to the best lubricant? (I use PTFE to reduce print’s adhering to the FEP too) Regards, Duncan

I have been following this thread with interest because I too am experiencing distortions at the earliest part of the print. You can see the buffer beam is twisting away from its correct alignment. Folluwing suggestions from @MikeTrice @njee20 @stevel and @Durley… I have tried printing with the floor towards the build plate with a twist as well. You can see that this merely changed where on the model it occurred - although still at the point closest to the build plate. It also produced heavy striations which can be clearly seen. I tried breaking any vacuum by putting 0.25mm slits between the planks at the low end. This removed the horizontal marking seen on the body of the first image but did not eradicate all distortion of the solebars and headstock at the point closest to the build plate. I then wondered if it was due to the thickness of the buffer beam or weakness at the join between the solebars and headstock that might be the cause so printed a wagon with reinforced corners and one with a thicker headstock Niether solved the problem but the one with an extra 1mm thickness on the headstock appears to be slightly better. The distortion of the solebars abs headstock rather than above the wagon floor makes me wonder if it is entirely a vacuum issue and whether angle supports might be contributing. I intend seeing if changing the angle of supports alters things. Thoughts and observations very welcome. Duncan

If you can identify any inter-regional workings that might help with the exLMS stock. In GWR days you could look up the working of through coaches (available in the National Archives now) which gives the origin of through coaches and owning company. You’d still need the divisional local coach working diagrams to get the local workings and their composition. Regards, Duncan

I seem to recall the map of the Greenwich nuclear free zone showed the boundary going round the RN college…

A bit too catholic for my tastes. How about the Mercian and Wessex Junction Railway? D

The impact of the London naval treaty is quite fascinating. Not only was it (and the Washington naval treaty in 1922) the catalyst for appeasement, but it also led to a marvellous piece of British duplicity in the shape of the 1935 Anglo German naval treaty. While this annoyed the French and broke the Stressa front - things which weren’t going to stop Germany anyway - it let the Germans have a u boat arm again. This seems mad until you understand the level of deviousness in the Admiralty. Up until the Treaty the Germans were building a highly specialised commerce raiding fleet (think pocket battleships) something that might stretch a resource strapped RN (thanks to naval arms limitation) to breaking point. The clever bit of the treaty was to play on German naval cultural insecurities and persuade them to build a smaller version of the RN (Raeder’s 1945 plan). How is this clever? Because that was the very fleet the RN was best able to defeat - a smaller version of itself. Submarines were not the problem that they were in 1917 thanks to convoy and sonar. The German development of pack tactics on the surface after the summer 1940 was unforeseen (as was the collapse France and fall of Norway which transformed the Strategic maritime picture in a way no one could have foreseen); even so, convoy casualty rates never reached a point where the British war effort was imperilled. D

You should enjoy the suggested reading then. Lambert’s Seapower states is a good starting point as it covers a lot of the high level political, military and cultural stuff.

There is a lot to unpack here: war v peace policy and construction; pre and post Napoleonic ship design; impact of new technologies; balanced fleet v threat/scenario specific fleet (to use Richard Hill’s terminology); impact of globalisation on the preeminent sea power; seapowers v naval powers; fleets in being and how to deal with them; frigate and cruiser development; political v military role of navies; globalisation of trade and its impact. First, President (1829) was a direct copy of the USN ship. This made her immediately obsolete in construction terms (the Stebbings system was already in RN use, as was iron for structural components, both of which permitted larger ships or heavy armaments for a given size and was possible during the Napoleonic period). She was also too big for trade protection and scouting duties - what RN frigates and cruisers were for. Therefore her purpose was not military, it was political - which is why she was used on the N American station. The US super frigates were the creation of a naval power interested in military issues (the means) not a sea power interested in economic matters (the ends of naval power). It was the precursor of the Mahan/Corbett debate that is still alive today. (BTW, Corbett was better at strategy than Mahan. (James should warm to both Corbett and Prof Andrew Lambert is they both trained in law before realising there were greater things out there…) Super frigates were designed to break blockades and carry out commerce raiding. They were not battleship substitutes despite there size. The RN needed lots of frigates for trade protection and blockade work; making them small meant they could be afforded, could be built quicker with less resource and needed fewer crew. We see this carried on right up to the London Naval treaty in 1930 when the US wanted large 8” gun cruisers to support a battle fleet while the RN wanted numerous small 6” gun cruisers for trade defence (because seaborne trade was politically and economically import to the UK in a way it wasn’t for the US). The UK Labour government over rode Admiralty advice and imposed a cut on RN cruiser numbers to get a deal. It was one of the principle causes of appeasement (together with a battle fleet too small to fight 3 enemies at once - hence all the efforts in the 1930s to keep Italy on side and appease Germany while the RN (until c1936) got ready to fight Japan (after 1936 Germany was the main foe). Warrior and the black fleet - yes very interesting period. But warrior was not a frigate! What is going on is the RN has developed a new strategic system to do two different jobs. A power projection fleet to push sea power ashore (and solve the what happens when the opposition refuse to come out and die question - you go in a get them) in the shape of a costal attack fleet (low freeboard, steam powered turret ships) developed from the littoral attack fleet that won the Crimean war (yes, RN won that war too, only it was won in the Baltic, making the armies attempts to gloss serial incompetence the most inappropriately named war in history). Warrior was from the other fleet, high freeboard, sailing with auxiliary steam power able to move long distances and remain at see for long periods to carry out trade (and imperial the two terms being synonymous at this point) defence. I have gone on enough… Suggested reading: A Lambert, Seapower States A Lambert, the Crimean war J Beeler, Naval policy in the Gladstone Disraeli era. E Grove, The RN since 1815 M Robson, A history of the Royal navy: the Napoleonic Wars M Farquharson Robert’s, a history of the Royal Navy: WW1 D Redford & P Grove, The Royal Navy since 1900: a history D Redford, A history of the Royal Navy: WW2

I would say that the consistency in style across several hands up to WW1 is probably more to do with the education system (and the system around Swindon) at that time than anything else. D

These are the standard gauge books. There are only 3 broad gauge wagon stock books that the NRM admit to. The highest BG number there is 12000, build date Apr? 20, 1889, but this is clearly not the end of the run as it seems far to convenient a number or finish on. D

@Compound2632 You are quite right. Here are the correct entries.

So it is ?47?. The first and last numbers are rounded so possibly 5, 6, 8, 9, 0 maybe 2. The brake lever guide is to the left of the w-iron, not the right where one would expect it for a 9ft wheelbase wagon, suggesting it is a longer body and longer wheelbase. Looking at the possible numbers the wagon stock books give: 5470: 17.6x7.3x0.11, wood frame, single brake, tare 4,16,0, grease a/bs, 10ft w/b, built ?Glos Wgn Comp? Jan 21 1862, cond 31/8/1885 5472: 17.6x7.3x0.11, wood frame, single brake, tare 4,15,0, grease a/bs, 10ft w/b, built ?Glos Wgn Comp? Jan 21 1862, cond 25/6/1906 5475: 17.6x7.3x0.11, wood frame, single brake, tare 4,14,0, grease a/bs, 10ft w/b, built ?Glos Wgn Comp? Jan21 1862, cond 23/4/1910 5476: 17.6x7.3x0.11, wood frame, single brake, tare 4,17,2, grease a/bs, 10ft w/b, built ?Glos Wgn Comp? Dec? 3 1861, cond 13/7/1912 5478: 17.6x7.3x0.11, wood frame, single brake, tare 4,16,0, grease a/bs, Ok oil ab fitted Apr? 1908, 10ft w/b, built Glos Wgn Co Dec 31 1862, cond 18/5/1896 5479: 17.6x7.3x0.11, wood frame, single brake, tare 4,16,0, grease a/bs, 10ft w/b, built ?Glos Wgn Comp? Jan21 1862, cond 31/8/1885 6470 isn't a 1 plank. 6472 isn't a 1 plank. 6476: 15.6x7.5x0.11 1/2, wood frame, double brakes, tare 4, 4, 0, grease A/bs, 9ftf w/b, built Worcester lot a, 30 Aug 1865, cond 14/10/1905. Double brakes rules this one out. 6478: 15x7x0.11, wood frame, double brakes, tare 4,10,3, grease A/bs, 9ft w/b, built ? could be Gloucester Wagon? 1867, no lot number, cond 1/4/1905. Double brakes rules this one out. 6479: isn't a 1 plank. 8470-9 are all 'timber trucks', so not them. 9470-9 are loco coal wagons so not them either. So one of the batch 5470-9 seems the best bet. These do seem to have been built by Gloucesters, so can anyone with access to the Gloucester records confirm or point to any surviving builders photos? Hope this is useful to the other GW wagon enthusiasts out there... Duncan

If I remember the events correctly (no, I’m not that old, but more that it’s not my area of history), the USS President was so badly damaged that she couldn’t be commissioned into the RN, so to ensure the name went into the RNs books (and to ensure the noble traditions of rubbing ex enemies noses in it aka ‘showing off the prizes’ could continue) an exact copy of the President was made and it was this that entered service with the RN. If my recollection of one of Prof Andrew Lambert’s anecdotes is correct HMS President was used as the Flag Ship of the N America station during several periods of tension with the USA just to make sure the don’t mess with us message was received loud and clear in both the USN and Washington DC….