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Schwarz-Brot

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Everything posted by Schwarz-Brot

  1. Yes, that is a constraint. Constraints are only available in sketches AFAIK. To define a sketch you work with dimensions, quite obviously, but it is in most cases more elegant to use constraints as well. Things like parallel and orthogonal orientation, centering, tangents and coincidence and some more are available. These help you aligning geometry in sketches without breaking out the calculator. Some things can only be described to the CAD system by constraints - for example coincidence can be calculated and given by numbers, but to make a closed outline that can be extruded you need the coincident constraint. But applying a sketch or a canvas to a plane is a constraint as well, if you think about it. If you work with multipart assemblies and apply joints these are also constraints.
  2. Your klutz approach is actually not too bad at all. If I have to trace a 3d curve in Inventor I'd usually work with splines to define the outlines with some control. Freeform modelling is not allowed at my workingplace. To get fixing points my goto approach is as follows: Add a plane for every known crosssection and sketch that crosssection on this plane, say from nose to back of an airplane. Make sure every sketch is completely fixed by constraints and measurements - this is key in parametric modelling! Next is Crosssections from ground to top: create planes, add the crosssections. To give them something to snap to you need to project the points where the vertical "slices" cross the recent plane. These points are your anchoring points to lay the spline along. as described in my post above. This is how I do it in Inventor. The workflow in fusion might be slightly different. I personally would always opt for the freeform workspace, as it gives better control and we don't need solid models for printing. Maybe I can do some writeup on this with an ongoing project. Edit: In fusion you can open the projection toolbox by pressing [p] when in sketching mode. If this does not give you usable points you may have to leave the sketch and manually place points at the intersection of sketch and plane. These points are available from the same dropdown menu that lets you set workplanes. These points can then be projected in the sketch or maybe even catch automagically.
  3. @Mattlow Fusion sometimes acts funny when placing sketches. It often happens to me that I select a plane to place a sketch on, then place some geometry in that sketch and find it to be snapped to some part far away from my sketching plane. This is a behaviour I really cannot figure out and don't see with Inventor. It might be of help to you to manually place constraints. I think the "coincident" constraint would be of help here: select the constraint in sketching mode, selekt the point you need to fix to another geometry, then select the geometry. A point can be snapped to other points or to straight lines. If you need to snap it to curved geometry it may work in some situations, in others you'll have to project the geometry first, then snap to the projected line. Hope that helps or at least gives you hints what to google next
  4. @Jamie @ Sovereign Hobbies Let me spare you some time... The linked diyodemag tutorial is a good starting point if you come from nothing. The first 3 parts are very helpful to get to grips with the concepts of parametric modelling. Rendering is not important, you can skip that one. Part five may be of interest in some special cases, it essentially teaches how to use (and abuse) the spiral tools. Part six is probably not at all relevant - didn't read through. Part 3 might seem like very useful, but don't be fooled. Building models by blending sections is an operation with very little control, not at all parametric. So you might as well leave the realm of parametric modelling and enter the world of sculpting tools. With these you can control every aspect in every dimension. Not easy to get used to. I'd highly recommend to follow the official tutorials before drifting off to youtube or written sources. It is important with these tools to really understand what they are meant to do. This series is essential imho: https://help.autodesk.com/view/fusion360/ENU/courses/AP-C-CONCEPTUAL-MODELING-FUNDAMENTALS If you follow these videos you'll quickly see this is what makes fusion really powerful for our purposes. Edit: @LostCosmonauts I have plenty of the make books, but to be honest I hated most of them. They are usually helpful if you start from nothing, but leave you with more questions then answers when things get more involved. My main concern is they are usually written by selftaught "experts" and more often then not contain solutions that work in some way, but are often done in a questionable way from a professional view and thus get in the way if you start digging deeper. The diyodemag tutorial linked above contained some things I'd do very differently as a trained CAD professional, which showes the author is not above experienced hobby level. I found no real mistakes, though, just awkward solutions to get to the results. But they work and would do so under all circumstances, so no worries from my side.
  5. Yes, I can rescale easily to 1:8 for Pocher and others. In that scale hex-bolts should work out just as fine if there is demand. Downscaling is not possible as I am at the limit of a robust and repeatable design. I might do smaller ones with the hint of a hole to drill out manually, but to be honest, this is a task I wouldn't recommend doing. I think this is only doable repeatedly with a jig and watchmakers precision tools.
  6. Hi Andreas, the topic title gave me the picture of a Britmodeller internal link list. Great idea! There's great 3d printing topics sprinkled all over BM and it would be good to pull these together in one place with a little comment on what is going on and what is the topic. Ideally splitted into topics like Naval, Planes, military vehicles, civillian vehicles. Would you by chance be interested to curate such a list? Or would you prefer me starting such a topic to curate it? Obviously we'd be dependent on the input of our fellow modellers, as most of us specialize in a specific area of BM.
  7. I foresee quite a lot crossreferencing and copy-editing to get all the information sorted into suitable topics in a digestable format
  8. Nasa has a repository of 3d files: https://nasa3d.arc.nasa.gov/models/printable
  9. I'd like to jump in before @LostCosmonauts gets to write all the articles about 3d printing. My goal with this thread is to collect some information about software tools useful or needed for 3d printing. The list is by no means final, so if you know something or feel the need to correct some information jump right in. If you have some information about software not listed yet, please post it with some additional information. Creating 3d Models for print There's several ways to get models for printing. The easiest thing to start out is using a platform like thingiverse or cgtrader to get some models to start with. Can't find it? Hire a 3d artist - many are taking jobs via these platforms - or create it yourself. First thing to decide is what kind of model are you going to do: Something highly technical with many regular, symmetrical and angular features, or something very organic or with complex curves This gives a hint about the software to chose. Technical parts are ideally designed in a parametric CAD package. You can go back to any aspect of the design and set every part of the geometry to a defined size at any time. This is perfect for scaling and parts of known sizes. Organic parts are better approached with a 3d modelling or sculpting package like used for animation. What is important to understand is that you are not bound into one or the other world. For kit manufacturing it is easy to do the technical parts in parametric CAD, then import the model in a 3d sculpting software and design tubes, cables and tire patterns there to fit to the exact geometric parts. This way the strength of both worlds can be leveraged. For the average hobbyist high end software for professionals is likely unaffordable and for sure the wrong thing to invest in if you just want to test the waters. Luckily there are very powerful free or open source packages available that are not much behind the commercial offerings. Highly recommendable for high end use are the following: After the model was created it is time to export it to a format the printer software understands. This usually means STL format. These days almost all 3d software can export to this format, so no worries here. Checking and manipulating your files Why would you do that? It may happen you downloaded a model that wasn't intended for 3d printing. Then it may have areas that lead to errors - holes in the mesh, unfused edges, inverted surfaces... Things like that. Or the model needs to be hollowed out. You may have overhangs that are not printable and lead to missprints. You'll get the terminology when you dig a little deeper into the topic. Some printing software will throw errors at you, some will simply freeze and some will let you print anyway to find out something went wrong later. You may also have some files you need to cut into several pieces to fit them to your build volume or maybe wont to distort the part in a simple way. This can be done with the big tools above, but some simple tools go a long way here. Printing and slicing A 3d printer works by adding layer upon layer to build up the volume of the model. To do so it needs to know what these layers should look like. The slicer takes the model and breaks it up into layers of a defined thickness. With many printers you are free to use whatever slicing software you happen to have and like. Some printers only accept a proprietary file format. Often your slicer will be able to translate to that format. Sometimes you are bound to the printers original software. Usually the software that comes with your printer is good enough to get you going and do most things. Often it is a specialized flavor of an open Source slicer. Because of this I cannot recommend something specific - all I use these days is chitubox which is packaged with my printer. Please feel free to fill this blank space! Please commit to this topic by adding your goto software and writing about what it can do and where to get it. My hope is to get a little collection over time that helps others to find alternatives and information to get started on the software side at all.
  10. I did a printrun of very simple parts that needed to be done in multiples. https://www.britmodeller.com/forums/index.php?/topic/235077497-wire-locking-bolts-for-large-scale-vehicles/ Thus I could not simply print a lot and then ship them out - I had to ensure a consistent print quality and this was the main time consuming part - redesign, testprint, redesign, testprint. In the end it worked out fine and I did not intend to make real money from it, but it is really time consuming to get a design to the point of consistent and repeatable print quality. I now have the design at a point were I could simply print away and be sure it would come out fine, so further prints won't be a hazzle. Next thing I always have in mind is the bad reputation any kit with poor fit receives. With large scale kits, especially Pocher, it is a real love-hate relationship. I wouldn't risk my reputation shipping out poor fitting or damaged parts. 3d Platforms usually give you the possibility to set a licensing option. Of course this won't prevent copying the files, but our community is quite small, so the risk is at a minimum imho. You might want to check out our new 3d printing area - your topic would fit in there perfectly.
  11. Well, be careful what you wish for. If you consider the hours spend on designing the parts a complete engine would cost you a fortune if anyone would make this a business. Nick, your parts look really good for a newcomer to CAD design. I am really impressed. It shows what powerful tools the average guy has right now to work with. Obviously the time invest is high and leads to a shift in modelling from the real world into the digital domain, but the results are stunning.
  12. Brilliant sculpt. And what a beautiful paintjob! I'll never be able to imagine something different for this one - your interpretation is just perfect. Very moody, very convincing.
  13. So this is where the design started from. The dimensions are according to reneks sketch. The pontons are designed by hand to bind the bolts together in multiples for easy handling. They are needed in the printing process and are part of the support structure. These bolts are nice to print as the support stem also acts as an integral part of the design - this is rarely the case but super nice because there are no suport marks to be cleaned off of the final part. The upright orientation without any angles also means there are no visible layers in the final part. The height of the head was lowered in later parts and the orientation of the holes was rotated 90° - thus allowing me to blow them out with compressed air before postcuring. This was the next iteration in 3d CAD with the smaller head: And after several iterations I ended up with these - the final parts after cleaning but before postcuring. At this stage they are still very soft and sometimes feel sticky. Postcuring hardens the resin further and afterwards the parts feel like regular casted resin. I know at least @Sloucher put his bolts onto his model, showing the result. Maybe I can persuade him to post the picture here as well.
  14. This is a test post, but I think something meaningful is a good idea. A while back on this thread by @Renek he showed a sketch of wire lock bolts he got printed for his Alfa Romeo Monza in 1:12. Some users voiced an interest in these studs, and I jumped at the opportunity to see what I could do. It was the first attempt at creating parts from scratch, not working from existing 3d files. With several active users we developed the design further - the users from a design perspective and me to optimize printing. For example the head of the screw was shrinked considerably to optimize the look. All of course with printability and stability of the part in view. Several testprints were done on the iterations. This way the orientation was optimized for cleaning up the printed parts and aid with painting. The hole size was adapted in several steps to find the best tradeoff regarding print quality, cleaing out and stability. The design itself is very simple, but the process showed all those involved - including me - what it takes to take an initial design and turn it into something that can be printed with repeatable results. I guess we all learned quite a bit from it and I can only encourage all of you who start out with 3d designing and printing to start with such a "simple" design, maybe even go and try to repeat the process - the initial sketch and dimensions can be found in the thread linked above. The discussion was held in private as this section didn't exist yet and it was not really clear how and where to show parts that were intended to be sold. I am most happy to see this makerspace area where such an discussion can be held in the open. I found it most educational. A shoutout goes to all involved: @Sloucher, @colin, @Bengalensis, @Renek, @Armchair Thank you, guys. In the following testpost I'll show some pictures. Test editing: The bolts were made for the Italeri Alfa Romeo Monza Kit in 1:12. They should fit all cars of 1:12 and larger.
  15. Another one from the initial question: Is it affordable? I'd say yes, if you don't mind the time invest and have the skillset to design parts. - Resin printers are easy to setup and very cheap. The cheapest usable would be the elegoo mars at the time of writing. This one is exclusively distributed via Amazon. Add about half of that as additional initial costs: Resin, IPA, gloves, spatulas, containers for cleaning... - FDM printers are ultra cheap to get - my first one cost me about 80€ - but you get what you pay for. These are tricky to get setup just right and you really get what you pay for. For quality results and good community help I'd look at a Prusa i3 - 780€ at the time of writing. These are open source hardware and there are many clones out there you can get way cheaper. But quality is a gamble then. If I was in the market again I'd go with the i3 Mk3s kit. But sind my FDM printer sees no use anymore I probably won't invest anytime soon. Jan
  16. One question wasn't really answered yet: How well do 3d printed parts age? - PLA, ABS, Nylon - most of the extruded materials are your common thermoplastics you deal with in every day life. They might vary in colour over time, but usually won't crumble under the influence of sunlight / UV. - Resin for 3d printing on the other hand is designed to cure under the influence of UV, this means the process never really stops. Freshly printed parts are very flexible and won't break under normal circumstances. They need to be hardened some more using the sun as an UV source or some kind of curing station (Nail polish curing boxes are a very cheap and usable possibility). Overcured parts or unprotected parts harden to the point of becoming very brittle, they are probably not workable anymore without breaking them. This won't do no harm to already assembled parts, but will be a problem with pieces that see some sort of handling. I therefore always inform my clients to store their parts in a dark box and paint as soon as possible. Other points: - PLA can be glued and melted with your usual hot plastic glues and is overall pretty comparable with your average kit plastic. ABS is harder and cannot be melted with the usual plastic glues. CA and 2k glues work well with all extruded plastics. - 3d printed Resin dust is as toxic as usual resin. TAKE CARE and use a mask. - resin is toxic. Not only for you, especially for nature. DO NOT WASH IT DOWN THE DRAIN!!! IPA used for cleaning must not be discarded that way. You can try to harden the washed out resin via UV curing or let the IPA evaporate and cure out the resin fallout before throwing it away. Better yet bring it to your local toxic waste facilities. - Resin printing is messy. Make sure you have dedicated tools for cleaning up uncured parts, cleaning up the work area andeverything else that is handled around fresh resin. Screwdrivers and spatulas, everything will be covered in a thin resin layer that cannot reasonably cleaned away every time. Just make sure you handle these parts always with gloves. - Use Nitrile gloves with resin. Latex won't protect your digits, the resin goes through. - I personally use thicker nitrile household gloves. These are reusable over and over again. - I highly recommend using a resin printer in a dedicated area or better yet room. It shouldn't be too close to where you sit. The stuff is smelly and makes a real mess. - A glass tabletop is ideal - very easy to clean. - All 3d printers should be used in a very well ventilated area. Molten plastic isn't exactly healthy to inhale when you think about it. Resin smells ugly and is probably not better. Hope you find some useful bits of information in here. I do own FDM and SLA printers. SLA has more uses in model building in my opinion. FDM is more for structural parts but can't handle tight tolerances well and leaves messy layers. If there are any questions feel free to ask. Jan
  17. I found the MB archives, but couldn't find the one with measurements on. Had hoped to find more blueprints there as this would be the most reliable source one could ask for. The google picture search is my usual way as well, but with most historicaly significant cars it is hard to determine what you are looking at. Often it is replicas or inofficial drawings, blueprints most often are taken from model instructions and sold as the real deal... Still better than nothing, but nothing beats original plans in my book. Even if I don't intend to build a subject I love to drool over original technical drawings, trying to figure out what went on in the engineers' heads. There's just something special about beautifully handdrawn plans. In my company I sometimes even recognize the draughtsman by their style of placing dimensions and details. Maybe I'm a bit to obsessed overt this...
  18. Are you going to put a little weathering on? To me the panel lines look a bit harsh on the clean bodywork.
  19. These are great plans you dug up there. Where did you find these? I bet Tamiya quality and fitment is a big difference in what you are used to. I expect a gorgeous build - might be a little too easy for you
  20. Don't give up too soon on the Monza. Just give it some time, build up some confidence and then look at it again at a later point. I at some point started to build models anyway, even if I seriously messed up. There's still enough to learn along the way and techniques to test and gain confidence in. Most of these never see the light of day again, but at least you got them finishend and not as a burden on the shelf of doom. Disaster recovery can give you some nice learning experiences as well. Good to see you posting. I'll follow
  21. So brutal - might play a role in the original mad max with that photo backdrop. I love this car and I love your build. Very very nice result. The original cars of that time probably never were polished to such a shine, but it looks soooo right.
  22. Hope to see a WIP thread on the next kit as well. You show some fine work and the pointing out of the differences to the 49 is surely helpful to those tackling such a project as well.
  23. Barry, I have the same train of thought going on regarding my Pocher F40. It would be a shame to display the car with opened doors and chassis as it compromises the raw yet refined lines of the F40. On the other hand NOT displaying all the oily bits with an exceptionally transkit thrown at them would be also a shame. Along these lines I already thought of using the transkit and Pocher engine parts to do all the structural parts with all the technical bits to the highest level I possibly can, and doing a simple scratched subframe for the complete hull with interiour but without unseeable drivetrain and motor detail at all. I love the idea of showing these side by side. The Car itself draws immediate attention a simple display of oily bits would never do. But once you have the attention those overdetailed parts make for a stunning display piece. At least in my mind.
  24. simplest thing to do would be painting it metal all over and using a dark wash to make the lettering stand out.
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