The model is finished, I sent it to the printer last night, and got a look at it today. Some of this printed, some didn't! More to come soon!
Ok, got busy and didn't have time to post more than the finished models, but I've got a bit more time now, and on to the results of the print! So first things first, yeah, it was a failure. Unusable model, but part of the learning experience. What failed so badly then? Well the first thing is that the model broke away from the supports at the rear of the model; so the pilot and stairs on the short hood end of the model are completely mangled. Looking at the sill, it could be that some of the supports detached from the model there as well, but that is more likely due to the forces involved in using the scraper to detach the model from the build plate. It tends to cause the model to bend and can cause broken supports. I'm now using Lychee for the first time in generating my supports structure, and that possibly is the root cause of my supports failing. Looking at earlier in the thread, I did have a successful shell print, so I know a good print is possible! Okay, right, the print is a failure in terms of failed supports, but still, the above photo shows a concerning issue. The end of the deck is warping, and the handrails are not working! The deck, right at the end of the hood seems to have detached from the support, and the warping I'm seeing might be related to the vertical part of the handrail that merged into the deck. But the handrail itself is expanding too much, enough that it's bending the posts! Now I have no idea what to do about this. @SLSF Freak, you posted a picture of a 3d printed handrail in one of Sumner's threads a while back, do you have any advice for the handrails? Also, what radius have you found works for you? In my case I used 0.5mm for the handrails, 0.4mm for the grab irons. Other than the warping handrails and the problem with the supports, the rest of the details have printed rather well! The radiators printed very nicely, including all the slats in the the large rectangular air intake. The Sinclair antenna is likely fragile, but printed even with the gap! All of the little eyeles on the top of the hood printed, but they are super fragile, I broke some off just handling the model. However I didn't bother completely removing all the supports, and so I did not post-cure the model under UV lights, so of course the details a lot more fragile than they would be normally. Even the bell printed rather well.
The slits in the side cover are looking awesome, and the air filter cross hatch pattern came out perfectly well. As for the front of the shell, at the end that did not detach from the supports, there's some good and some bad. First, the MU hoses did print fine. I'm rather happy at how the hoses are each individually bent into a different shape, just like real hoses. Obviously if I printed more than a single, it might look repetitive, but I only want one for my layout. The button "step" is warped, but that's due to the inadequate supports. The bars that attach to the front of the pilot did not work. The bar that sits just above the coupler is sagging, despite the supports I added to it, and the bar at the top of the pilot came out as a mess. Maybe my problem here was that I tried to print them at 0.4mm. So all the details I'm going to keep as is, except for the bars on the pilot. I gave it a try, but maybe it's best to do as the manufacturers and just mold those bars into the pilot instead of trying to make them free standing like the real thing. Either that or I would need to use brass. Anyway, that's it for now, if you have any suggestions on how I could fix any of the issues, I'd be happy to hear from you!!
This thing is going to look so good in paint! It's a little hard to see in the raw print, but you can tell the details are really going to pay off. So, the ends ripping off supports is something I'm familiar with. So much so that I've done my own type of support for that area - there is nothing delicate about the supports I use on the ends (see pic) Basically the supports are just a support rod going right up into the model - no tapered point. You have to use cutters to cut as much as you can off, then a small file to get rid of the rest. Other printers will tell you to print it tipped up at an angle so the pull forces aren't so strong - that is an option. I don't like the streaks and artifacts that causes in mine so I print horizontally if it will look better that way. I use the same diameters as you're using for handrails and grabs... .5mm and .4mm respectively. I do print them separately though. In the calculus of deciding how to print these I count on things like handrails failing at a higher rate than something like a shell. Hate to throw away an entire shell because the handrails failed (and if I break the handrails later, I can replace them) So handrails are printed with rectangular mounting pins that fit into sockets on the side of the sill piece. I have another design for the CF7 that I'm trying where it's just the handrails and stanchions, with the stanchions having the mounting pins almost like an Atlas or Kato shell: http://alwayssolutions.com/kits/cf7/index.html. Oh, and one other note about handrails - this may not be the same issue you're having with them but if I soak them in the alcohol for a while they get "waterlogged" and expand causing them to bend between posts... kind of like a spaghetti noodle. Once they dry out completely they tend to shrink again and take their intended form back. YMMV on that though. In conclusion- it's a pain to do setup like this where literally I'm doing all the supports by hand and designing pieces (handrails, horns, cab, sill/walkway, shell, plows) that fit together like a puzzle. But for a project where I'm printing several kits that other builders will be putting together and painting it makes sense to take the time and do it that way. For your RS18 I'd maybe give the separate handrails a try so you can replace any that break in the future, but leave most of the shell as a single piece since it's a one-off. Cheers -Mike
Thank you! I've been working on this model since early July, so it's a lot of hours, though I'm not sure exactly how much - some weeks I didn't even open the file. The thing is it's relaxing! I just open the program, and just start building away. It's like Lego I guess If it's any indication of "work", so far this model has 168 sketches, my biggest by far! For comparison, the gondola I made previously was only 50 total sketches. Of course, a Fusion 360 expert might have done it in half the sketches Mike, thank you so much for your post!! A lot to go through, so just going to start with the supports. As you know I took the recommendation to print "flat" from you in previous discussions and I completely agree with you about the better detail and fewer streaks. I did try making some of the support structure in Fusion 360, but honestly, I didn't like it. For me at least it was super slow and just didn't work out (just the amount of sketches was getting to be a pain!) However, I'm now in the 30 day period of evaluation for Lychee Pro, and honestly, I'm really impressed by the program. There's a few features that really stand out for me: 1. The mirror tool!!! You can enable a plane along the x, y or z axis, and whenever I place a support, the support is automatically placed on the other side of the model. For locomotive shells, this is a huge time saver. 2. Accurate placement of supports. I setup the grid that appears on the plate to show 1mm x 1mm dimensions. Unlike Chitubox, when you view the model from the bottom, the grid does not disappear! So I just press the '0' key to switch to Orthographic display, and then look straight up, and I can accurately place my supports at the spacing I want. 3. Adding bracing. In Chitubox, the app decides for you when to add bracing between supports. But not here, no bracing are added, and when you decide to do so, you can select just the supports you want and then have it add the bracing. Super convenient. 4. The biggest one yet, and this is my favourite! You can modify the base model and keep the same supports! For example, I was halfway through adding supports to the model when I realized I forgot to mirror the window frame to the other side of the shell. In Chitubox this would be half an hour lost. But In Lychee, I was able to go back to Fusion, fix the model, re-export, and then update the model in Lychee. The supports didn't move. That made me so happy you wouldn't believe. Anyway, so getting back to the actual issues I had with my print. I think the problems with the failed supportsis that I used smaller supports than I normally would have in Chitubox. That and it could be that my garage is getting colder - I may need to add a bit more time to my printer. So yeah, the solution is simple, I'm going to re-position the supports under the model, especially at the ends, increase the support size, and I will add those massive supports at each corner, thank you for the picture for that! Yes! I've been busy yesterday so I just left the uncured model on the workbench and went to Halloween my my daughters. Checked when I got home last night and the posts are nearly back to being straight. I'm curious if they would have bent back to shape had I post-cured them in the UV light?? I'll have to remember to do a test on whether I should let a model dry out before post-cure. However, this does bring up another little thing that came up... In an earlier post in this thread, I showed a video of the last print mounted on the mechanism. It doesn't fit anymore! I noticed this just a few days ago, when I wanted to fit the shell to the mechanism to measure a clearance. But the shell is now too tight front to back. I printed the shell at the very beginning of August, and I did not add any primer or paint. But the model was not sitting in the sun, just on my desk under regular basement lighting. Anyway, the front and rear walls of the shell are 1.5mm thick, so to prevent any problems I had already carved out .15mm out of each end before printing. Just a weird thing that I didn't know could happen with these prints. I'm going to see about printing the handrails separately, that's what I'm working on for now. It makes sense and I do agree that it will be easier to repair once I inevitably break one in the future Again, thank you so much for your post and the pictures. Giving me great ideas on how to setup the handrails on my RS-18!
Alright! this weekend is print "take two" I separated the handrails and front/rear guard rails from the body. Should make it easier to print and clear the way to stronger supports on the shell. The only thing standing in the way is chores unfortunately - gotta change to winter tires on the cars and a bit of yard work for the coming winter. Lucky, at least the horn and brake wheels I had already designed to print separately. It's not easy going through the Fusion 360 sketches and making changes. Everything is relationships, and mess with one and 3-5 different things can break 50 or 60 sketches down the line. 'Manage Lost Projections' only goes so far. I'll post pictures once I get a new print, hopefully later this weekend.
Bah! Another failure. I have a nasty gash that runs roughly midway up the shell - you can see it in the above picture, on the side of the short hood, beneath the door handle. Nasty thing goes around the entire shell... On this side, it caused the supports for the lowest grab iron to fail (and the drop grab iron is half failed), and the gouge is readily visible on the side of the cab, below the window I think it was caused by static electricity. I usually have a rule to not touch the machine while it's running. And today, during the print, I touched. I wanted to see if the machine was hot, and I broke my rule and touched it. sigh. I learned this mostly with my older Anycubic machine, I once touched it during a print, felt a shock, and the print stopped with the hardware crashed. I had to reset the machine for it to work again. Anyway, I have no proof that the line was caused by my touching the machine, but well, here we are. Still, all's not lost. The print mostly worked! I did have few support failures, but only the secondary tiny ones (0.30mm) that I use for little details. It's weird though, because I used those same 0.30mm tiny supports on my previous attempt and those had not failed For example, in the above first picture, under the little step leading up to the cab, there's a 0.30mm support. On my previous print, all of these tiny supports survived; here only one survived. hmmm, you know, maybe those broke during washing? The steps all printed fine (and the bell, and the grab irons, etc), so the support must have broke post print. In any case, You can see that in the pictures, the shell and details are still on the build plate. So despite this being a bad print, I still want to try removing some of the supports for the details (bell, steps, grab irons, pilot, etc), and then post-cure the shell partially before removing the rest of the supports. I want to see if I can minimize the warping this way. Might as well test the handrails on something that will be a throw away as well. And next time - don't touch the machine while it's running
I removed the supports, cleaned up the print a bit. Still having trouble seeing details with this blasted clear resin, so I blasted it with an mostly empty can of tamiya primer, just the rear of the shell... Seems a bit rough, but it's also just 15 minutes after putting on the primer, which is an old can. The pilot detail I think is okay, the top "bar" kinda merges with the pilot itself, but the end loops and visible. The lower bar (coupler lever? not sure what that might be) I'm not sure I like. The outer ends are fine, but it's the middle part that I'm not sure about. I might just do away from the middle part. That's what Rapido did on the dash 8-40CM models I have The biggest problem I have is the hand rails. They printed fine, but the pins I added that go into the deck are 0.3mm diameter. The holes are not printing at that size. And I don't have a drill bit small enough for that. So I'll have to try and see if I can order smaller sized drill bit. Even then, I have a feeling those hand rails are going to be a pain to clean up properly and attach. I wish I could make the pins larger, but then the holes will be too close to the edge of the deck and will cause failures. This is a bit of a head scratcher right now. Almost wish I was in HO scale, sheesh, the details there are HUGE! Barely an inconvenience!
Why not fabricate the handrails instead of printing them? You could print the stanchions separately, and use a brass or copper wire for the railing. Do you think it would be possible to print a hole or drill one in them? A #80 drill bit is 0.3429mm in diameter. You could do the same for other parts like grab irons and cut levers. Instead of fiddling with getting these tiny details to print correctly, why not use aftermarket superdetail parts? You could print the mounting brackets for the cut lever, but then install a bent-wire version after the model is complete. You could do the same for grab irons, either print through holes or drill starter points and then add wire details after the print is complete. I feel like that would be the more traditional method for detailing a model. I'm not sure if you addressed this idea earlier in a different post, as I'm just jumping into the middle of a thread.
I want to see how much and how far I can 3D print. I do have some .10 and .16 brass wire (K&S) that I briefly tried bending to grab iron shape. But the things are so small, not easy to get them bent just right, and repeatable. I know there is a tool available, but at 50$ US plus shipping, that's ridiculous. Maybe I'm not using the right wire, but the brass wire I got from the hobby store is so soft, it's super easy to bend out of shape. As for buying aftermarket details, that's just a preference, but I'm trying to not use any of these on purpose. There's absolutely no good reason for this, just a weird rule I set for myself on this project. A while back I thought about 3d printing only the stanchions and using brass wire for the handrail, just like you said, but before today, I did not know that drill bits smaller than that #80 you mentioned existed, so hadn't thought it possible and dismissed the idea. However, a few minutes ago I ordered a set of drill bits for PCB boards, ten sizes from 0.1mm to 1.0mm. I'm looking forward to experimenting with this. It would certainly make for cleaner handrails if I can use wire.
You could print a jig to help with repeatable wire bends for the handrails at least. I'm not sure that would work with the grabs though. Here's a better (I think) view of how I designed my handrails. With each you can see there are hefty mounting pins into the shell to keep things sturdy. The areas where I do use small pins to mount are less for strength than for just holding those ends in place at the cab and steps. For the U-Boats you can see I opted for using one large panel for strength, then for the CF7 (right side) I wanted to try to get completely separate handrails but still use chonky pins. They both work pretty well: The issue with your RS-18 is that those stanchions aren't on the side but are top mounted. Even so, you could still do something similar to what I've done with the U-Boats if you want to put in juuust a few more hours. Here are these rails on the models: Cheers -Mike
I'd be happy with Mike's above. Look great to me considering the restraints of trying to do all things to scale in N scale. I did make some from.... ... guitar strings. They are .010" about 1.6 inches scale. First attempt. Probably could get a little better with practice. Here is the info on those... http://1fatgmc.com/RailRoad/Locos-1/page-7.html Sumner
Might have gone a bit heavy with the primer, but after six months, I'll leave it as is! printed the shell at 30 microns, first time I do this. Made for quite a long print, but worked well overall. The hand rails are 3d printed, but not yet glued into place, same with the guard rail op front and in back. Brake wheel (I assume it's a brake wheel?) and the horn are also not glued in yet, just press fit into the shell. So now it's time to paint, and I'm not sure which colour to use yet. I initially wanted the green/yellow, but I just don't know how I'll do the yellow, I've got decals for them, but impossible to apply around the bell, headlights, number boards etc. So I may just do the black/red scheme.
Beautiful and the detail is fantastic. Looks like you got the handrails down. You should be mighty proud to of going from a blank sheet of paper (blank CAD screen) to this. I think most of us have no real idea of the time and CAD skills it takes to accomplish doing a shell like this (same to Mike and his efforts). I'll bet you get the paint job also, Sumner
Awesome job! I hope you're able to look at that with a sense of pride for what you've accomplished. Now you've proven there's no stopping you since you've done the hard thing. So much work and it looks incredible. Looking forward to seeing the next phase - paint, then back on the rails!! Cheers -Mike
Thanks all! I am very happy with it at this point Trying to find decals is getting to be annoying though, the microscale 60-567 are sold out everywhere I know of, even the local hobby shop.
7-8 hours to mask and paint the nose crests on each end. Basically, I started the masking over and over until I finally got it right, and then sprayed the yellow. Only to find that the paint leaked under the masking tape, and the layers of yellow needed to cover the green made it so thick, ARRG! So with a fine brush, alcohol and patience I was able to correct the overflow and get something done that looks good when squinting from across the room Anyway, the photo is after applying another coat of satin varnish, so I'm plunging forward with the decals next and just gonna see this one through using this scheme. The black and red ends could have been so much easier, but I just couldn't find decals for it, and I have the decals already for the green/yellow scheme. I should probably go back to the 3d model and build the hood and deck separately too, but the Fusion 360 file is nearly corrupted. If any change is made to the timeline it takes several minutes for the computer to update, and then breaks half the model. Though that's entirely my fault, I caused the problem by extruding parts as 'join', but with some of the bodies that would be joined set to 'hidden'. Don't ever do that to try and control the join operator, it just makes your fusion 360 life so much harder later on, lol. To fix the model would be to delete all the railings and some of the pilot details, and properly define them as components. edit: my next shell, if I ever got to do another, will have separate grab irons and handrails, too much of a hassle to do them together.
Looks good to me and I can't imagine the hours you have into it to get to this point. One thing that might help is after taping spray some of the color you are painting over at the tape edge first and then go onto the new color. The old color should seal the edge and help prevent bleed. Use light coats and don't spray at the tape, 90 degrees at it if possible On the Fusion are you saving/exporting the file to your computer so that you have versions to fall back on if needed? I probably over save files. I've been working on my coal mine the last few days and have over 30 copies of it saved. I save anytime I make maybe 5-10 changes to the design. So I have lots of copies to go back to. Also the whole main coal mine building has thousands of surfaces due to the siding. It will start taking a few minutes to update or save and I bought a higher end computer a year ago to help with that. When that happens I save what I'm working on as a new component by using the 'Create new component from body' command. Then copy that and put it in a 'new design' and save and export that. Usually working with it then results in much faster updates and I have the last version saved in case I have to go back to it. You probably already know all of that. Oh, and I can't imagine that this is the last loco you do Sumner
