RBE Posted April 30, 2013 Share Posted April 30, 2013 The question is really can I realistically print N gauge bogies in FUD without them breaking in use? Also would it be strong enough to print a whole wagon as I prefer the finish or am I better using WSF? Cav Link to post Share on other sites More sharing options...
RMweb Gold Revolution Mike Posted April 30, 2013 RMweb Gold Share Posted April 30, 2013 FUD is definitely strong enough to print a wagon. If the wagon doesn't have much surface detail (or if you can add detail via etches) then polished WSF would be an alternative. What type of bogies are you after? I would either print complete bogie in FUD with room for brass bearings but not sure how easy it will be to get wheels in, or print bogie sideframes separately to go on say an etched inner. Cheers, Mike Link to post Share on other sites More sharing options...
RBE Posted April 30, 2013 Author Share Posted April 30, 2013 Well thats good news. Im planning on doing the bogies in two halves that slot together to grip the wheels in bearings. I will do a model and pop it on for people to comment. Cav Link to post Share on other sites More sharing options...
Etched Pixels Posted April 30, 2013 Share Posted April 30, 2013 I think it depends what you print - laddering, long thin fine detail and stuff like trussing are probably going to be too weak in N. Flat wagon decks tend to warp. If however your wagon is structurally sound for other reasons (eg vans, open wagons, or having enough bracing then you should be ok. So a long wheelbase van is easy, an open you have to fiddle a bit to best hide the thickness of the material but is basically not hard, but a spine wagon is a whole additional world of pain ! For bogies I hit three problems 1. The stuff is very hard to glue so you want them one part 2. It wears rapidly so you need bearings on the wheels and for heavy use possibly also on the pivot and pivot surface 3. It's very hard to get them anywhere near an acceptable width without using 2mm scale association wheels and/or bearings The maths being 15mm over pinpoints means about 14.5mm over the inside end of the bearings and you need about a 0.7mm wall thickness minimum 14.5 + 2 * 0.7 = 15.9 and you've now got 8ft wide bogies which can look ludicrous. I'm dubious you'll be able to print slot together bogies and glue them strongly. It's easier to get the wheels in by dumping the bogie in 70°C water letting it soften a tiny bit and then inserting them. Same trick as resin basically. I did the Great Central 10'6 bogies in polished WSF with printed in pinpoints, NEM coupling socket and etched overlays for the detail and it works but is wider than I'd like. I went back to designing my own etched bogies for the Newton Chambers car carriers I'm currently building. All the other rules for strength you'd expect also apply - you can often make fine parts thicker in places that can't be seen (eg trussing width), make sure you fillet joins so that there isn't a point waiting to fracture under stress, consider where you need bracing and so on. Alan Link to post Share on other sites More sharing options...
RMweb Premium Nile Posted April 30, 2013 RMweb Premium Share Posted April 30, 2013 I've had my HOn30 bogies (same size as N gauge) printed in WSF and FUD. The WSF ones are very tough and will survive being dropped. The FUD ones look better, have finer detail, but are much more fragile. While they will survive normal use, they will break if dropped or mishandled. Definitely a case of handle with care. Link to post Share on other sites More sharing options...
RBE Posted April 30, 2013 Author Share Posted April 30, 2013 Thanks for the comments guys. Could be back to the drawing board if you pardon the pun. I originally considered a WSF bogie with FUD outers for cosmetics but the width was horrendous. My only hope really was a full FUD bogie but from whats been said Im not sure its worth the effort. I can get the bogies Im after as parts in any case I just wanted a cheaper option printing as a multi bogie sprue. The body may still be viable though. Cav Link to post Share on other sites More sharing options...
simon br blue Posted April 30, 2013 Share Posted April 30, 2013 Well thats good news. Im planning on doing the bogies in two halves that slot together to grip the wheels in bearings. I will do a model and pop it on for people to comment. Cav There should be enough flex in the bogie to print it as one part and bend it out to fit the wheels. The Campbells wagon has enough flex to fit the wheels in but I'm sure if it was flexed too much they would break off. I've printed some ladders on the 2mm POA model and they seem strong enough although they are fixed to the side of the wagon. On the 4mm PGA I got printed in FUD the handrails got broken when the model was cleaned and I was told that there wasn't enough support for it to be printed and cleaned. Link to post Share on other sites More sharing options...
RBE Posted April 30, 2013 Author Share Posted April 30, 2013 Was that POA printed in FUD? You got the wheels in that it seems. Am I fighting a losing battle trying to print an N gauge wagon? I really dont want a rough finish as seen on WSF but the wagons need to be strong enough to stand the exhibition circuit. Cav The PGA looks nice though! Link to post Share on other sites More sharing options...
Etched Pixels Posted April 30, 2013 Share Posted April 30, 2013 I really think it depends upon the wagon. Opens, vans and the like can work as they have a structure that stops them warping or bowing, and if you fillet the joins can be quite strong. All the finer stuff like laddering wants to be etched for things like exhibition use, and you'll certainly need brass bearings, and quite possibly want to go with metal buffers. For drilling, getting wheels in etc see my comment above - getting it warm makes it fairly easy to drill and gently bend. Another approach for some wagon types is to do what I do with the range of coaches I've done and things like the O.13 milk brake - use polished WSF to form a smoothed strong shell and then etched overlays. I've done stuff from Midland six wheelers to 60ft GCR coaches that way without problem, and the polished FUD with overlays works to 23m coaches (annoyingly 26m ones don't fit in their polishing spec) Alan Link to post Share on other sites More sharing options...
RBE Posted April 30, 2013 Author Share Posted April 30, 2013 The problem is Im trying to use the 3D printing as a cost cutting exercise. If I start etching and the like it obviously bangs the price per wagon up. I can already get a kit for the wagon Im after but its a little more than I want to pay for a full rake. I was hoping to get a load printed for cheaper. I uploaded a prelim pair of bogies onto shapeways and the price was about £3.50ish for the pair in FUD. If I did it as a full sprue of bogies it would come down a little bit more. I still need to do a body and upload it for a price though. I may be able to print a body and use atm bogies instead if the body price is cheap enough. Cav Link to post Share on other sites More sharing options...
lyneux Posted April 30, 2013 Share Posted April 30, 2013 I've printed 4mm bogies in FUD that are fine: http://www.rmweb.co.uk/community/index.php?/blog/864/entry-9340-arc-hanson-jha-part-6-revised-bogies-fitted-to-scratch-built-wagons Not sure about 2mm bogies. Price per pair is about £15 in 4mm so yes, should be a lot cheaper in 2mm. Having said that, I dropped one on the floor whilst painting last week (butterfingers!) and it broke off one of the 3-4mm square bolsters forming the main load bearing part of the bogie so they definitely much, much more fragile than say, ABS. Which bogie are you planning to model Cav? Link to post Share on other sites More sharing options...
RBE Posted April 30, 2013 Author Share Posted April 30, 2013 Its the Y25C bogie. As I said I can get them off of ATM for £5 a pair without wheels. Might just do that and print the wagon instead. Cav Link to post Share on other sites More sharing options...
simon br blue Posted April 30, 2013 Share Posted April 30, 2013 Was that POA printed in FUD? You got the wheels in that it seems. Am I fighting a losing battle trying to print an N gauge wagon? I really dont want a rough finish as seen on WSF but the wagons need to be strong enough to stand the exhibition circuit. Cav The PGA looks nice though! Yes the 2mm POA was in FUD, the finish doesn't look great but I didn't clean it properly as I messed up and the fit was too tight for the wheels to turn freely. Etched Pixels - where can I get some bearings from? and are they suitable for the Farish wheels? Also just remembered the 4mm PGA was printed in FD not FUD. Link to post Share on other sites More sharing options...
lyneux Posted April 30, 2013 Share Posted April 30, 2013 Its the Y25C bogie. As I said I can get them off of ATM for £5 a pair without wheels. Might just do that and print the wagon instead. Cav It's a no-brainer then. Don't bother with FUD if you can get ABS or resin for £1.50 more. FUD is brittle and cleaning it ready for painting is a pain. Link to post Share on other sites More sharing options...
Ozexpatriate Posted April 30, 2013 Share Posted April 30, 2013 Besides "Fear Uncertainty and Doubt" what is FUD in this context? I presume it is some kind of plastic. (I did do a Google search and didn't find anything relevant on the first couple of pages.) Link to post Share on other sites More sharing options...
lyneux Posted May 1, 2013 Share Posted May 1, 2013 Frosted Ultra Detail - a type of resin used by Shapeways for 3D prints. Link to post Share on other sites More sharing options...
Etched Pixels Posted May 1, 2013 Share Posted May 1, 2013 Bearings - 2mm scale association top hat for the smallest/finest ones. Do work with Farish axles. These are the ones used in most of the Ultima etched bogies for example. These are 1mm diameteter with a 1.6mm 'brim' - Slightly bigger ones (1.5mm) used in things like the Ultima Thompson CCT. Available from various sources in small numbers plus from Markits in bulk bags. Work with Farish axles fine - Parkside Dundas for little 'cap' like bearings as used in their 12ft chassis kit The 2mm SA also does 12.25mm long axles for N gauge wheels, which is about the only way I've found to do a decent width using 3D print, and also lets you do accurate solebar widths for etched dumb buffered wagons - which is pretty much essential. Another source of slightly shorter axles might be Mathieson Models perhaps - at 13.7mm or so. Link to post Share on other sites More sharing options...
JohnBS Posted May 1, 2013 Share Posted May 1, 2013 Cav, I found Shapeways FUD fine for anything that is a 'lump' or that is attached to a 'lump' - see http://www.shapeways.com/shops/SteamPrint . Also see 2mm Finescale forum on the Saint. The loco and tender are 2mm FS. Both have main structural elements 1.0 mm thick but tapering down to 0.3 mm on exposed edges. Things like the steps will be etched or fabricated metal as FUD would be too vulnerable. In the case of wagons, I would go down the route of a printed superstructure with etched frames, to keep thicknesses to a reasonable level. However the tender frames, in the absence of fine tie bars, appear to be robust enough. Generally, FUD is quite easy to drill, cut, file, chisel or Dremel, just like other resins or plastic. I'm not yet certain how well it takes adhesive but I would anticipate a bit of preparation, followed by epoxy, should work. Hope that this helps. John Link to post Share on other sites More sharing options...
Etched Pixels Posted May 2, 2013 Share Posted May 2, 2013 Cleaned I found Evostick Impact works nicely on it. I've had problems drilling it and it cracking but since I took to warming it up first (like resin) it's behaved rather better. Alan Link to post Share on other sites More sharing options...
Dazzler Fan Posted May 7, 2013 Share Posted May 7, 2013 In 4mm I am revising models with a FUD sprue for detail parts, and the main body in WSF. - I think the savings are worth going for, when a final brush coat produces a satisfying model. Noel http://www.shapeways.com/shops/hazelwoodmodelshop Link to post Share on other sites More sharing options...
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