Today is turning into a curates egg of a day. The chassis print is fresh out of the washer and there are obvious failures but 90% of it looks excellent. All the failures were easily explained by a quick look at the chitu file, if you don't add supports the print is very likely to fail. . Back to the drawing board, mean time the floor and internal bits print is running that's another 4 hours+ job.
Meatloaf had a hit with the song 2 out of 3 ain't bad, what do I get for 1 out of 3? One over supported, one under supported and finally one just right. The floor and internal structures look great. I have to say the loading ramps look very fragile, so after clearing the remaining supports it's now being cured but even then will need very careful handling, not my strongest point. A second revised print of the chassis is brewing now but wont be finished till about 7:00 tonight so it will be left till tomorrow morning after which a new body section will be printed. Curates Egg, pah, I just need to remember sometimes less is more. Mossy
The doors have also proved challenging, have initially only printed one set of end doors and one set of side doors. I added 4 set of each to the floor print. So out of 5 sets of each I have 4 righthand end doors and no lefthand doors. A clumsily placed support made every time a tried to remove it I damaged the hinges. Similarly I have 4 righthand side doors and 3 lefthand doors. More reprinting will be needed after revising the supports. The hinges are so fragile any further prints will need extras printing. What I also realised I don't have any sets of closed end doors, i.e. with the securing bar locking the doors closed. More to add to the reprint schedule.
Hmm.. ok Mossy. I’d still like to know what failed on the body? Looks ok with the support so what went wrong? We can all learn and sometimes the photo paints a thousand words.. as they say. look at my experience. ! Or lack of!
Andy Naff photos but its late and the light is awful. Because its an outside framed wagon I added supports to the underside of the outside framing, When I removed the supports it looked like zit city, pimples everywhere and pretty much uncleanable, this was fished out of the bin 5 minutes ago: I did a rerun yesterday, but zit city vanished. All I did was remove the supports on the underside of the framing, now I have nice clean undersides, lesson learned less is sometimes more:
The Bouch Brake Van I am working on this alongside the dgm 25 carriage van. I loaded the body into Chitu and for no good reason for a change I clicked on +All to auto create the support network. I know people like Mr Dundee seriously don’t like this function and when I have previously tried it the results were c...p. This time it look sensible and pretty much what I would have done manually, so rather than just deleting it I took time to examine what was being suggested. The more I looked the more I approved, ok I moved and deleted a few supports, mainly to make the clean up easier, and then thought go for it, print it and see what happens. The body fits on the Mono, so the X would be free to do other things with. 8 ½ hours later I had a perfectly acceptable body, almost. One corner of the cabin had failed but why. After a bit of digging and by recreating the auto supports and comparing it to the actual supports used, I found a single support which I had deleted which caused the failure. Seriously annoying. Perhaps auto supports aren’t as bad as their reputation. The failure: The opposite side: I have been fiddling about again this morning and what I have discovered is pretty simple but telling. If you select medium or heavy supports before auto-applying the supports, the results are distinctly odd, some look fine other awful, but if you selected light supports the results are far better. Ok there are substantially more supports but in the main they are in the right places and far better than the results with the other supports. I didn’t realise selecting which supports to use before auto applying was required but it does seem to matter. Has anyone any comments? Mossy
I always use auto support then check a few bits after. What I’ve yet to master is the % of support. Normally work around 60% subject to size and weight if the print, sometimes go with 70. I also start with small on auto add in my own medium and large to suit.. still can’t get rid of the zits though other than with a file. Would love to know how folk get them so clean?? Andy
Andy, I'm sure Mr Dundee would give you a long explanation, but fundamentally zits go when you print in 2 angles say 25 x 25 rather than parallel to the build plate. It &^%^& the print run times but does work. Best is 45 x 45 but ooooooch the run times. Same components, top printed parallel to built plate and partially clean up, but still zit city, below printed 25 x 25 with supports removed but no clean up, almost as smooth as a baby's botty. Mossy
Andy, I have been playing and fiddling with auto supporting over the last couple of days and basically come to the same conclusion as you, auto support using +All with light supports, then revise the support structures by changing lights for medium or heavy supports where appropriate. I still haven't figured out the difference between +Platform and +All, I can't really see any significant differences, do you know what they are? As for % of support that one shot way over my head, so I can't help with that one. I think I might have to do some research on it. Mossy
Mossy, The % is the density, how much of the surface area needs supports. 5%, 25, 60 etc.. that just depends on what your doing. Now what I don’t understand is the penetration? Your printing a flat surface? How do you decide how far something goes in to something?? Unless it’s simply how much of the points surface area is absorbed … Oh, my… I think the penny just dropped!
Andy Paul tried to explain penetration to me and I think he reckoned there are two circumstances where reducing the penetration helps. a) where there is a lot of surface detail, but support is needed, by reducing the penetration the support is more easily removed and causes less surface damage. b) where a support is actually defining say an edge more that supporting the structure, again reduce penetration, reduced damage, an example where I use this is defining the edge of a roof, most of the support is provided by structures under the roof, but I use light supports with a .2mm penetration around the edges. I use the second but rarely the first, instead I use a a tiny pair of scissors and a very sharp and often change No 1 blade in my craft knife. Mossy
The 3 model sandwich of body, floor/internals and chassis of the D25 hasn't been going very well so for now it's been parked awaiting a rethink. I have however been cracking on with the Bouch Brake and now have everything printed ready for assembly: I have also dug out another wagon, an R1 Coke wagon. It's an unusual one for the NER as it's the only mineral wagon in the NER fleet of over 20,000 which didn't have bottom emptying hopper doors. As with the brake van everything is printed read for assemby: All that's left to do is assemble them. Mossy
Rob Have a beer on me, they look cracking, especially those chocolate brown sides. The R1 is almost finished, on a 1-5 scale of difficulty it's barely a .5, I may well get to Harrogate on Monday. Mossy
With the wife away in the Italian alps for the last two weeks I hoped to chew my way through a backlog of wagons that needed printing but, my daughter managed to badly sprain her ankle, to the point where she could barely walk so I have been on grandad day care duty - it's k&*^%&*ing! Things have calmed down a bit so over the last few days so I have been able to build 2 wagons that have sat in boxes awaiting assembly. The first is an R1 Coke wagon, I love curiosities and is one, the only NER coal/coke/ironstone wagon that didn't have bottom "hopper" doors, and strangely for an 8' 6" wagon it has 4 brake blocks not the standard 2 brake block on opposite sides opposite wheel configuration. The second wagon is a P6 Coal Hopper, I'm not sure why I sketched it as its a post 1900 wagon, whereas most of my interest and wagons are pre 1900. It's pretty much contemporaneous with the P7 which is one of the Salter offering. They are slightly lower than the P7's and built I think because the P7's couldn't fit under the screens of some of the old pits, other than that pretty much a standard NER design, with 8 bottom doors opened by monkey hangers. Mossy
Bouch Brake Stage 1 Floors and all the handrails fitted. Roof just perched, lamp irons to be fitted last as they are very fragile. Next job axleboxes and wheels a nice easy job then the complex bit the brake gear. Mossy
It's bright and sunny in Leeds just now so before setting to with the axleboxes I decided to do the final bits of wire bending. There are 3 handrails on each side of the clerestory, tiny, fitted out with .5mm wire after horrible eye strain. The axle boxes will have to wait as grand day care has just kicked in. Mossy
More of Mossy's 3D prints passed across the workbench this week - painted and almost at the lettering stage. K1 Cattle Wagon V1/2 Brake Vans