Rob R

APL13 All being well I have a couple of outside framed 2-4-0's lined up using standard S axles and Markits axle extensions with either Markits cranks or more likely some of my stash of EmSoc/Sharman moulded cranks. West Midland Railway circa as running 1861, the Hawthorn is ex Oxford, Worcester and Wolverhampton Railway of 1855 and the E B Wilson (with passenger train) is ex Newport, Abergavenny and Hereford Railway about the same date (sorry haven't got the book to hand - RCTS Great Western Locos Vol 3). The Wilson engine of course is slated to use parts from Timbers' Brecon and Merthyr "De Winton"(please!). The WMR also had a couple of "De Winton" 0-6-0's from E B Wilson (Manning Wardle acquired the patterns etc when Wilson folded) amongst many other very do-able locos. Photos linked below. Hawthorn 2-4-0 WMR No.95 All to be found here Hereford History Images - Building the Hereford and Worcester Railway I only stumbled upon these photos recently and they are some of the best views of 1850's goods stock I have seen. More work for the printer! You are more than welcome to as many wheel centres as you need once I have sorted the manufacturing technique. Of course once this wheel is sorted I should be able to do the others as well. Keep safe out there Rob

First go at the 5 ' 7" plain drivers on the Mars. They don't seem to have shrunk on the OD but the square hole is a little snug and the counterbore for the retaining nut is too small in diameter and I am not convinced that the OD isn't tapered slightly. I am having another go now but with the print set to 19 deg to the build plate - the same angle that everything else seems to work at for me - to see if I can eliminate some, or hopefully, all of those issues. Worst case scenario is to place it at a fairly steep angle (say 60 deg or more possibly even 90 deg) but I'm not sure if I will run into concentricity/ovality issues. I may also tweak the drawing a little and put a small chamfer (say 0.1mm) around the back of the square hole just to help the axle sit true and square. Time will tell (about 2 hours and counting). Images taken straight out of the wash and before curing. Rob

The dome was hollowed out with Tinkercad, imported in as an stl, once it was in you can do what you want with it as per normal tinkercad limitations and then exported out again. BUT. There is a limit to the import size - 25Mb, ok for small bits but the Albion boiler assembly was too big at 29Mb. I have not yet tried the boiler on it's own but as all that is needed for a trial print is a hole in the top of the smokebox I might try the hole/hollowing functions in the slicer instead. It will have to wait until I'm off work next (monday) and join the 3d cad queue ( gnr open wagon, wheels etc). Have fun and keep safe Rob Ps. I think that Solid Edge that Jim is using may be able to deal with imported stls more like TC than Freecad or Fusion. Jim, if you see this what to you think? R

Thank You Timber. The first thing to do on the resin wheel front is to print some and work out the shrinkage and adjust the scaling accordingly. There are some quite useful engineering resins out there, about four times the price of the water washable stuff I am using at the moment but only pushes the price up to about 20p a wheel ( for the 5' 7"). I will post any progress on that in the Wheel Thread. Rob

I like the nice thin rim on that one. Would it be possible to thin down the rim on the driving wheel? Earlier locos tended to have a more spidery look. A thinner rim should print ok and once it is glued into the tyre it should be plenty strong enough. Thank you for posting your work on here. Rob

These are Flubrushes Caley boiler fittings he drew up a while ago. Just playing to see if it is feasable to do such fittings at a suitable quality and price for stocking in the SSMRS stores. Wheel centres for SSMRS rims are also on the play list but they may require a different resin. For personal S stuff the butterfly has, for now, settled on the West Midlands Railway, circa 1860 (and Frisco, Kansas City c1970). Keep safe out there. Rob

A close call last night. A run of Caledonian boiler fittings nearly didn't make it. Note too self - check the resin level before pressing go....

Timber, Thank you for posting these especially the wheel. I have a possible need of a 5' 7"plain driving wheel for an outside framed loco so I had a little play. A quick cut and paste:- Whether the resin I am using is up to the job is another issue entirely. Rob Apologies, probably should have put this on one of the other threads. R

Just been playing with the boiler and noticed that for resin printing it will need a hole putting in the base of the chimney through to the smokeboke for drainage/anti-suction (as well as hollowing out the dome). I have also found that at 29Mb the file is too big to import into TinkerCad to play with. I shall have to wait for Timber to upload the components. Rob

I have experimented with (semi) mass production and I seem to have a truckload of the things now.....

The above photos were taken before curing and the lighting has highlighted the layer lines. It didn't look anything like that in the flesh. Post curing the gloss sheen has gone and it photographs much better. The layer lines still show a bit but are virtually invisable on the print and will probably vanish with the first coat of paint. Overall not too shabby for a budget hobby machine. Rob

Cambrain Railways Albion dome kindly posted by Timber on the other thread. I have hollowed it out and thinned the flange a little. Elegoo Mars 2 pro. 0.025mm layer height. Elegoo water washable grey resin.

I think I have scaled the dome correctly -39% for S scale? I have also taken the liberty of tweaking it a bit, hollowed out so it cures properly and thinned the base of the flange a little. Printing now so I will find out in a couple of hours. Thank you for uploading this. Rob

Jim, Would it help with the 16 tonner fault finding if I had a go at printing it on the Mars? Ok, it would mean changing 2 things (machine and resin) but hopefully would eliminate or otherwise any issues with your machine. Are you curing in water? What angle are you printing at? I am printing at 25 micron layer height and Elegoo recommend 19 deg. I was just doing this on one axis but the latest print has been 19 deg on 2 axis and has come out great. Rob

Timber, If you need any test prints give me a shout. I am a lot cheaper than Shapeways.. Rob

Want one already (West Midlands Railway Nos 32 and 33, later GWR 278 and 279, E B Wilson of 1855). Keep up the good work. Rob

The second GNR 4 Plank Open print (with floor brace) is done and the diagonal crease/flex has gone. Still a few other minor issues but the direction is now firmly forwards. The retaining rings for the door catch pins are not printing very well so I will probably either remove them or make them attached to the main body all around. There is a slight mark across the width just above the headstock at the build plate end. This may just be a visible mark that will vanish under a coat of paint or possibly a crease where the weight of the print has deformed the end during printing. I will squirt some paint on it and see. Extra supports around here may help as well. Full steam ahead now on the solebar/floor unit where we shall meet a different set of problems in trying to get the two parts to fit together without too much use of the 10" B'stard file... Steven, The object of the exercise is to create of a range of wagons available to SSMRS members either direct from me, printed themselves or through the Parts Officer, hopefully tempting a few more to join our slender ranks. Suggestions for future project always welcome.

Hando, It is a Manning Wardle Old Class I. R

The modified design for the GNR 4 plank with an internal brace. This will be cut out, probably before curing. The pictures don't show but there is a member lengthways down the centre I know, the slicer screenshot should be in the other thread...........

Following on from the new topic of "Whats on the Computer" I have started this thread provide a repository for 3D Printing posts. There will be some overlap but I suspect the CAD to produce the .stl file (other formats are available) will be in the other thread and the Slicing and Printing process in here. To kick off with is the first test print of the GNR 4 Plank open. Not an unqualified success, although it is not visible in the photos there is a diagonal crease/blemish from one top corner. This is different to the suction issue I was getting with the RCH open, that was starting at the corner nearest the build plate. This is at the other end so I presume it is due to the unsupported sides flexing. Having spotted the crease I didn't bother washing the print too thoroughly before curing. With hindsight I should have as there is a bit of resin build up aroung the door catches so I can't tell if they have worked out ok. I have added an internal brace to the design and another print is on the go now. More details in the Cad thread. I am going to need a bigger scap box......

Michael, The topic of wheels is no less exciting than anything else here - especially 3d printed wheels. Stephen Rabone's Sscalelist email group (Groups.io) might a possible location if it's ok with Stephen. I know the Broad Gauge Society's e-group (also on Groups.io) has a folder for sharing print files - although there isn't actually anything in it at the moment - so I presume it can cope with .stl files. Paul was going to ask our (SSMRS) webmaster (Andy May?) about a place on the SSMRS website where files could be downloaded from but I suspect that they would only be able to be uploaded by the webmaster. Rob

Jim, A couple more thoughts. You had a successful print earlier with a floor so how about something like the attached sketch. Sacrificial floor braces (red bits) as part of the drawing rather than slicer supports, chamfered at the ends so they break out easily. Shape, quantity and width as required. The other thought is have you tried curing in water? The curing process is exothermic and you can get a lot of localized heat stress. I use a handy glass recepticle, just about wagon sized (jam jar!) filled with plain corporation pop. My understanding is that as well as keeping the print cool the water also diffuses the UV a bit and spreads it around more evenly. Onwards and upwards Rob

Jim, Have you thought of putting a small flange on the inside at the bottom to stiffen it? Something about 0.2 thick x 1.0 wide. Could also act as a locator for the floor or even be sacrificial? Just trying to think outside the (mineral) box. Rob

I have stopped work on the RCH Mineral for now as I need to investigate a different way of overcoming the suction issue during printing. I had got round it by just leaving a plank out of the floor but that seems a bit messy, so rather than rehash what I had done already I have moved on to the next project so I can try some new ideas from scratch. The plan is to print the sides and ends with headstocks and do a separate unit with the floor and solebars. Hot off the (virtual) press is the upper works of a Great Northern 4 Plank open. Late enough now, bed time. Rob

Ok. I shall add my tuppence worth. 1923 RCH 7 Plank Mineral Still evaluating the best way of printing open wagons on the Elegoo Mars 2 Pro but we are (to mis-quote 1970's BR advertising) "Getting There".