Have You considered getting a 3D printer

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Have You considered getting a 3D printer

Home Forums 3D Printers and 3D Printing Have You considered getting a 3D printer

Viewing 25 posts - 101 through 125 (of 185 total)
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  • #523492
    Steve Pavey
    Participant
      @stevepavey65865

      I wonder what blacksmiths said when the first metal turning lathes and pillar drills were introduced?

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      #523494
      Tony Wright 1
      Participant
        @tonywright1

        Oh that’s a good idea it will make my work more accurate ! But it’ll still be me using it .

        #523500
        Nick Wheeler
        Participant
          @nickwheeler
          Posted by Phil P on 29/01/2021 11:38:21:

           

          When I was on training courses for Solidworks, they told us that people who were moving from 2D found it harder to learn than people who had never used CAD at all.
          We don't bother sending our people on the course anymore, I can get someone up and running on Solidworks in a few days with no drama.

           

          I had an hour week for a year 'learning' Technical Drawing when I was 14. That was 36 years ago and although it's left me able to read a drawing, I can't manage to create anything more than a rough sketch.

           

          What makes 3D CAD a breath of fresh air is it eliminates the need to know how projections relate to faces, scale to fit on the page, work out geometry for awkward shapes, calculate origins/depths/distances or all of the other techniques that try to represent a 3D object on a flat piece of paper.

           

          Instead you make a rough sketch(Fusion 360 even calls it a sketch) of the basic shape, constrain it so it stays looking like it should, add dimensions and extrude it to a solid. If you make the sketch over the mating part you already built, you can use its dimensions so everything fits as it should even when you make changes. Knowing it's a bit of square material with a hole in it with a plate bolted to each end is how you'll make the part is also how to model it. My grinder head was built around the 20mm diameter post and a layout sketch for it and the spindle axes; if I change the distance between them on the sketch, all the other parts alter with it. I actually did this to bring them as close together as space allowed. The rest of it started with an externally modelled ER32 collet chuck, then its holders, slide, pivoting base, work table, uprights, pivot, linear slides and finished with base, trimming and adjusting sizes as I went.

           

          Animating the joints has shown that the table doesn't need 45 degrees of tilt in each direction which will make cutting the locking slots easier. There will be other changes; the rails for both the grinding head and tool slide are currently to be L-shapes milled from solid; I'll be changing them to two sections bolted together with the fasteners needed to attach them. Looking at it, I don't think it needs to be made from 10mm steel sections or a 6mm thick table. Reducing those would mean less work and material cost.

          I could create drawings for each part from the model, but they're deliberately simple so isolating the part to work on and displaying the dimensions directly on it will be enough for most of them.

           

          I've had no training in CAD, but have been modelling most of the parts I've made for the last couple of year to learn about it.

          Edited By Nicholas Wheeler 1 on 29/01/2021 13:14:32

          #523507
          SillyOldDuffer
          Moderator
            @sillyoldduffer
            Posted by Tony Wright 1 on 29/01/2021 09:54:34:

            The skills required for 3d are computer skills not model engineering ! Using a band saw or a hacksaw you still have to physically do it .Carving a piece of wood is hardly engineering is it . I was Just taking it to it’s logical conclusion.Like cnc it’s the computer program that’s doing the work.

            Is this an unusually narrow view of what Model Engineering should be? I spot some misunderstandings too.

            My random collection of Model Engineer magazines shows our forefathers considered almost anything technical fair game. One of my 1919 magazines has no models in it at all, and a long article on Wireless Telegraphy.

            While computer programmers need deep computer skills, most users don't. Only necessary to understand how to stop and start programs, and to learn how to navigate applications of interest. 3D CAD is just another tool that happens to run on a computer. Like anything else it has to be learnt.

            CAD isn't super-human. It saves time and money, for example by automatically adding facts to model as they develop. By designating a part is made of steel, the computer can calculate the weight automatically. Even better, the weight is recalculated if the material is changed to something else, like Aluminium. Once a computer model includes physical characteristics, CAD is able to do more advanced stuff like identifying where designs are too weak or too strong (overweight). Information like centre of gravity is available as a by product – the designer doesn't have to use reference books, do tedious calculations by hand, or build several prototypes. And once a model is defined, it can be imported into other models, so standard parts like gears and fasteners are a doodle.

            CAD doesn't do the most important part of design – imagination! So there's little difference between conceiving a manual design and the same in CAD. CAD has no magic button to convert vague ideas into reality. Designers still have to plan, think, decide and review. Once learned, CAD relieves the designer of most of the drudge work, but it doesn't do creativity. That's our job.

            CNC is just another time saver. In the good old days metal was shaped with cold chisels or forging. Then came files and grinding, which some at the time considered a threat. Milling machines are basically motorised precision files, and they too were disapproved of by traditionalists. Preceded by automatics and other mass-production methods, CNC is just another step down the same road: it keeps machines busier than humans can manage. Each change shifted the nature of the skills and techniques used, but they are all valid. Being different doesn't make anything wrong or inferior.

            I don't have a problem with traditional skills or modern methods, they're both wonderful. Hand and brain are equally admirable. Nor do I have a problem with history, motorbikes, aircraft, electricity, chemistry, astronomy or computing on the forum. Diversity is one of the main attractions.

            Dave

            #523509
            Phil P
            Participant
              @philp

              The very first thing they teach people on a Solidworks training course is that you have to get the "Design Intent" sorted out before you start modelling anything.

              Basically that dictates how you proceed, for instance if you are designing a Tee slotted table for a machine, you would most likely start with a sketch of the end view and then extrude your solid shape form that sketch to whatever length you want the table.
              If the design intent changed it is then very easy to alter the original sketch, or the amount you extruded it.

              If you started with a sketch of the top of the table you would have a lot more work to do if something changed later on.

              Another thing that can be done is "Design in Context", that means if you change a dimension on one part, the rest of the assembly will update to reflect those changes if you do it right, so a design change request can be implemented very quickly and the results seen in minutes rather than hours.

              The other massive advantage of 3D CAD is its ability to produce fully dimensioned manufacturing drawings with very little effort. Then if the design changes, the drawing automatically updates as well.

              I am very lucky to have been using it at work for years, and also use it for my hobby as well.

              We generally only upgrade every three or maybe four years, so at work we currently use SW 2018, and at home I still use SW 2014, the upgrades add a few bells and whistles but are not always going to change much for 95% of what you use.

              Phil

               

              Edited By Phil P on 29/01/2021 14:21:38

              #523515
              noel shelley
              Participant
                @noelshelley55608

                One of the uses given for a 3D printer is that of pattern making. I have had numerous 3D printed patterns sent to me to be cast and almost without exception they have been useless ! The little ridges that are the layers it is built up of make it immpossible to remove the pattern from the sand. Only with considerable extra work in filling and sanding can these patterns be of any use. What is the way to resolve this ? It would be good to be able to advise those who suggest 3D printing as a pattern making method how to achieve a workable pattern. Noel

                #523516
                JasonB
                Moderator
                  @jasonb

                  Usual ways seem to be chemical fuming which disolves the surface so any layers "flow" and become smoother. The other is painting with a few coats of a high build filler primer and light sanding between coats. Obviously the better the printer quality in the first place the less the layers on the printed surface.

                  Funny enough some of the patterns I CNC cut last year originated from an enquiry about using 3D prints for patterns, The stepover between cuts I used was far greater than most 3D printers produce yet they needed minimal sanding and were cast straight off the bare wood and no sign of machine marks, in both cases the two foundries complemented the patterns.

                  #523531
                  Tony Wright 1
                  Participant
                    @tonywright1

                    I’ve just spent two hours making a big end out of a piece of scrap brass Using basic lathe and drill. Most enjoyable.We must agree there is no right or wrong way to make things ? Just enjoy your work before the covid gets you!

                    Tony .

                    #523532
                    Tony Wright 1
                    Participant
                      @tonywright1

                      image.jpg

                      #523535
                      noel shelley
                      Participant
                        @noelshelley55608

                        Jason. The problem arises from the hundreds of little ridges. AND that people fail to understand the need for a good surface finish with a draft angle. The merest hint of under cut causes trouble and 3D printing produces may be hundreds of them. I agree that an industrial quality machine will reduce the problem and other processes help. The hobby printer does not seem able to fullfil the need as a pattern maker without much additional work.

                        Your CNC wooden patterns would have no relavence in this context, being cut from solid and I assume you understood the basics of pattern making.

                        In small items whilst fuming may leave you somewhere near the required dimensions, without very careful design Etc the build up and sanding will leave the pattern oversize, and that is assuming the shape allows you to be able to sand.

                        My point is that before people buy a 3D printer thinking that it will make their patterns It's not that simple, unless their prepared to spend £1000s

                        That Neil, in MEW described a lost 3D pattern process was interesting but without VERY careful melting and burning out runs the risk of inviting disaster ! Noel

                        Edited By noel shelley on 29/01/2021 15:52:13

                        #523537
                        JasonB
                        Moderator
                          @jasonb

                          Noel those points you are making are not so much due to 3D printing but to the skill or lack thereof of the pattern maker. No draft, undercuts, etc . The texture of the pattern is just the last straw. No doubt a poorly made and finished wooden pattern would present may of the same casting problems, I'm sure a sawn piece of wood will also have a problematic texture

                          This comes back to Tony's comment that it is a lot more involved than pressing a button and the relevent skills need to be learnt and an understanding of the basic principals is still needed.

                          I would not say you need to spend 1000s, there are those that know what they are doing who can pull a good casting out of the sand with no layering on the surface with minimal outlay.

                          Edited By JasonB on 29/01/2021 16:24:08

                          #523540
                          not done it yet
                          Participant
                            @notdoneityet

                            without very careful design Etc the build up and sanding will leave the pattern oversize, and that is assuming the shape allows you to be able to sand

                            Don’t castings have a variable shrinkage when cooled down? A quick spray and sand, followed by a finish coat surely should not take the casting out of spec when the shrinkage is not exactly a 100% science?

                            Most certainly the patterns should arrive with a suitably smoothed surface finish, but that is another matter – it should be made clear to the pattern maker before they despatch them, to avoid any groans and moans.

                            #523550
                            SillyOldDuffer
                            Moderator
                              @sillyoldduffer
                              Posted by Tony Wright 1 on 29/01/2021 15:40:41:

                              image.jpg

                              Excellent, but not what 3D printers are for!

                              Can you make one of these Tony?

                              tank.jpg

                              Note the curvy shape of the slotted body, the importance of keeping the weight down, and the need to make dozens of individual track segments that will fit together and run.

                              I bet you can do the design but would struggle to build it. A lathe and pillar drill aren't the best tools for this one.

                              Horses for courses…

                              Dave

                              #523596
                              Anonymous
                                Posted by Tony Wright 1 on 29/01/2021 09:54:34:

                                Carving a piece of wood is hardly engineering is it

                                Well that's put the pattern makers of old firmly in their place. sad

                                Andrew

                                #523601
                                Nick Wheeler
                                Participant
                                  @nickwheeler
                                  Posted by Andrew Johnston on 29/01/2021 20:50:10:

                                  Posted by Tony Wright 1 on 29/01/2021 09:54:34:

                                  Carving a piece of wood is hardly engineering is it

                                  Well that's put the pattern makers of old firmly in their place. sad

                                  Andrew

                                  How about coach builders? Boat builders? The joiner that built the circular staircase in the corner? Can we really afford to exclude everything that doesn't have a toy steam engine?

                                  #523602
                                  Tony Wright 1
                                  Participant
                                    @tonywright1

                                    Pattern making ,piece of cake . As a cabinet maker I made many patterns for vacuum forming also for model aircraft manufacturers. It’s not difficult is it ? Well it wasn’t for me ! Also the tracked device when do you want on ? Give me a shout and I will quote you a price! Also what have these crafts got to do with 3D or model engineering, 

                                     

                                    coach builders? Boat builders? The joiner that built the circular staircase in the corner !

                                    tony 

                                     

                                     

                                    Edited By Tony Wright 1 on 29/01/2021 21:20:49

                                    #523610
                                    Ian Skeldon 2
                                    Participant
                                      @ianskeldon2
                                      Posted by Tony Wright 1 on 29/01/2021 09:54:34:

                                      The skills required for 3d are computer skills not model engineering ! Using a band saw or a hacksaw you still have to physically do it .Carving a piece of wood is hardly engineering is it . I was Just taking it to it’s logical conclusion.Like cnc it’s the computer program that’s doing the work.

                                      When you can stick a persons head on your lathe or mill, scan it and produce the equivalent of a 3d radium mask to accurately pinpoint a tumour inside a brain, give me a shout I will happily come along and watch how a real old fashioned engineer does it.

                                      #523611
                                      Nick Wheeler
                                      Participant
                                        @nickwheeler

                                        They're all engineering.

                                        In 3D.

                                        Model Engineering would be far better if we replaced Model with another term. Hobby? Home? Small? Craft? Or just ' '.

                                        #523615
                                        Roger Best
                                        Participant
                                          @rogerbest89007

                                          I skimmed through the notifications trying not to get irritated by a few provocative comments, and I now find some very good essays here on the thread! Looks like this topic has got people going. smiley

                                          Its great to see that people appreciate that CAD is an opportunity to be creative, and 3D printing allows a lot of creativity. Its real engineering, by making super material-efficient shapes you can make amazingly strong and light structures, ideal for aerospace and satellites.

                                          Its also great for modelling as numerous n-gauge modellers have demonstrated.

                                          The very exciting stuff, using metal rather than plastic, is still a bit expensive for home use but its out there.

                                          As eloquently stated above you shouldn't decry it, its not easier just because its not a traditional craft, its just different. That is as rude as a person looking at a prize model steam engine and saying that it was easy because the technology was centuries old and the design was copied from the original.

                                          #523618
                                          Peter Spink
                                          Participant
                                            @peterspink21088

                                            Horses for courses!
                                            3D printed bracket for cam belt cover/timing set up.

                                            Cam cover bracket.jpeg

                                            Timing marks.jpeg

                                            The rest the old fashioned way.

                                            #523622
                                            Ian Johnson 1
                                            Participant
                                              @ianjohnson1

                                              Out of interest Peter what type of filament did you use for the bracket? I would think it would get hot so close to the engine, maybe hot enough to melt PLA?

                                              I'm just getting into the world of 3D printing, my new toy, the Ender 3 V2 can use PLA or ABS, I'm using PLA at the moment because that's all I've got

                                              Nice engine by the way

                                              IanJ

                                              #523625
                                              PatJ
                                              Participant
                                                @patj87806

                                                I apply a thin skim coat of sheetrock wall patching compound to my 3D printed patterns, and then sand back down to the original surface.

                                                This gets rid of the lines that you get with a 3D printer.

                                                The Prusa produces a much better surface finish than the first 3D printer that I had.

                                                I see people using bondo and wood putty for fillers, but the problem with those is that the are too hard, and so it becomes a chore to get then sanded down, and the pattern is often damaged during sanding since it is softer than these types of filler.

                                                The wall patching compound is not very hard when it dries, and so sanding goes quickly.

                                                The secret is to use a compound that sands very easily.  Don't use hard fillers.

                                                I apply a coat of shellac once the pattern has been filled.

                                                It seems like a tedious process, but with the wall patch compound, it does not take very long.

                                                Below is an example of a frame for a small engine that I filled.

                                                This example uses more filler than I normally use these days, but you get the idea.

                                                This example is also painted, which I no longer do; I use shellac which dries very fast.

                                                If I am making a one-off casting, the wall filler will be sufficiently strong to make a few molds.

                                                If I want a more durable pattern, I use a double shrinkage factor in the 3D print, and then cast a permanent pattern in 356 aluminum.

                                                One feature I like is to make the surfaces of a pattern slightly convex.  A 3D printed pattern with a flat side looks visually concave, and so making the surfaces slightly convex if possible seems to make a part more visually appealing, and not have such stark lines to it.

                                                rimg_2358.jpg

                                                rimg_2389.jpg

                                                 

                                                rimg_2390.jpg

                                                 

                                                rimg_2392.jpg

                                                Edited By PatJ on 30/01/2021 04:42:22

                                                #523629
                                                not done it yet
                                                Participant
                                                  @notdoneityet
                                                  Posted by Nicholas Wheeler 1 on 29/01/2021 21:10:50:

                                                  Posted by Andrew Johnston on 29/01/2021 20:50:10:

                                                  Posted by Tony Wright 1 on 29/01/2021 09:54:34:

                                                  Carving a piece of wood is hardly engineering is it

                                                  Well that's put the pattern makers of old firmly in their place. sad

                                                  Andrew

                                                  How about coach builders? Boat builders? The joiner that built the circular staircase in the corner? Can we really afford to exclude everything that doesn't have a toy steam engine?

                                                  Question: Is this fellow an engineer? See his videos on making factory motorcycles into something considerably different! Look up Allen Millyard on you tube

                                                  Woodworkers are not generally thought of as ‘engineers’. Lots make models.

                                                  Perhaps model engineers were mis-named a generation, or three, ago by a bit of hype at the time when the lowly ‘metal model builders’ were all elevated in status by calling them all engineers, likely by naming a magazine as latching on to the term?

                                                  I have no axe to grind. No thoughts to stop the hobby using the term. Just thinking of where/how the term might have originated – and stuck.

                                                  #523630
                                                  Peter Spink
                                                  Participant
                                                    @peterspink21088
                                                    Posted by Ian Johnson 1 on 29/01/2021 23:59:24:

                                                    Out of interest Peter what type of filament did you use for the bracket? I would think it would get hot so close to the engine, maybe hot enough to melt PLA?

                                                    I'm just getting into the world of 3D printing, my new toy, the Ender 3 V2 can use PLA or ABS, I'm using PLA at the moment because that's all I've got

                                                    Nice engine by the way

                                                    IanJ

                                                    It's PLA Ian, hopfully being water cooled it shouldn't get hot enough to melt it – time will tell!

                                                    #523634
                                                    Nicholas Farr
                                                    Participant
                                                      @nicholasfarr14254
                                                      Posted by Journeyman on 29/01/2021 10:39:53:

                                                      I think 3D printing is part of the engineering skill set. Take a simple job, *****************************************************************************************************************************

                                                      Now I would suggest that drawing is an engineering skill it demands some sort of knowledge of how things are shaped and fit together it is quite possible to draw something that cannot be manufactured, be it whittled, printed or fabricated.

                                                       

                                                      So****************************************************************************************************************************************************

                                                      3D printing – just another engineering skill for use as needed with everything else in the workshop.

                                                      John

                                                      Hi, and here's a typical example.

                                                      Regards Nick.

                                                      Edited By Nicholas Farr on 30/01/2021 08:49:50

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