Drawing board v CAD

[MonomanParticipant @monoman]

Anyone who doubts the ability of Fusion 360 to produce really good quality, buildable models should look at the recent work of 'Crueby' on the MEM (Medel Engine Maker) Website where he has two comprehensive build threads.

'Lombard Hauler Engine' completed **LINK**

and his current work in progress 'Chris' Marion Steam Shovel' **LINK**

If you look at the easrly stages the two projects you will see the quality of the drawings he has made and from which works.

My understanding is that he learned Fusion 360 from scratch to build the Lombard, which you can see steaming and running in the last of his posts on that topic.

[Mike Palmer 1Participant @mikepalmer1]

We all work in our own way and old habits die hard, but those who have looked over the hill to see the sunny new uplands are having a great time. Like a lot of things in life we form opinions without actually experiencing the issue. I took up CAD and CNC around seven years ago without any prior experience with either, and yes, I did struggle but once the penny dropped I was away, after 51 years as a model engineer I was reborn making things that I considered beyond my skills. As a previous contributor mentioned it taxes your brain thus keeping it active and most of all very enjoyable, which after all said and done why we participate in this wonderful hobby.

Go on have a look you won’t regret it

Mike

[NealebParticipant @nealeb]

I started many years ago on a drawing board as an apprentice in the Marconi DO School, but some considerable years later picked up a cheap copy of TurboCAD on a visit to the US. I updated that a few times but always struggled with it in 3D. 2D – pretty good, but never quite got to grips with its 3D capabilities. From what I have seen in demos at exhibitions, this does seem to have improved a lot from my version. One area that I always struggled with in TCAD was making changes. I often ended up deleting and redrawing as being quicker than editing. Again, this might well have improved in current versions.

Then I discovered first of all OnShape, then Fusion 360 which I now use. A lot. Its ability to visualise in 3D (like picking up an object and rotating it in your hand), "change history" (go back and edit a dimension and all the follow-on changes automagically happen – if you've created your drawing properly), parameterise key dimensions to make easy changes – all these speed drawing and reduce errors. For me, anyway. I'm currently redrawing in F360 the Don Young Black 5 drawings (very much for personal use only, I hasten to add). One driver for this was the odd comment in the "build manual" that builders had found an error in a stretcher that caused a clash with the tender wheels. The 3D model shows this clearly, allows me to use sectional views to take dimensions for modifying parts, etc. I could do this with 2D, but given the list of "this then that" dimensional dependencies between wheel flange and stretcher, it would be an error-prone pain to do – which is presumably why DY didn't notice it in the first place. Just one example.

One very important point about using 3D CAD – and especially with a parametric, time-line and constraint-based system like F360 – is to understand some of the underlying principles that make it very different to drawing in 2D. It is much less like drawing and much more like modelling, with the spin-off benefit of allowing you to create drawings from your model. Unless you understand some of these principles, you are never going to get the best out of it.

However, I do accept that a lot depends on your own abilities. Some people (talk to a good architect, for example) have the ability to visualise in 3D in a way that I cannot even understand. They can probably stitch together a 3D visualisation of a set of drawings but many of us cannot. Horses for courses – I find F360, if not intuitive, then at least easy to use after a bit of practice and the combination of visualisation plus producing a variety of drawings for workshop use works for me. And, generally, I can visualise parts for the purposes of holding and machining (even if I then forget and leave out a vital step…)

I am also an enthusiastic user of Vectric Vcarve – great CAD/CAM tool for 2D working, which I use a lot in conjunction with a CNC router for woodwork. Unlike F360, it provides the minimum of well-chosen drawing tools that meet the large majority of needs.

Back-of-the-enveiope works for me as well, sometimes!

[Clive FosterParticipant @clivefoster55965]

Swarf Maker

Thanks for those suggestions. Looks like that may be a better way for me than going via the videos on the main Fusion 360 site. We shall see. As usual formal course based learning needs more connected time than I really have. I can see I'm gonna need some more printer cartridges!

I guess I'm not alone in having come into CAD by the pragmatic route of needing to draw something to make it. But by their very nature 3D systems have to be design first then make (almost) anything within reason so the whole thing has to be much more complicated. Folks like me who pretty much go from vague visualisation and perhaps a few paper scratches direct to 2D drawn parts struggle with the formalities of doing a right design first. Doesn't help that much of what I do is repair parts, modifications or make something that does … to fit this. So the design is pretty much a given making direct to 2D easy. Its getting on board with the formal design process that's difficult because I'm used to a starting point pretty close to where Fusion breaks out the completed design down to 2D parts drawings for manufacturing. Skimming through the tutorials its almost scary how much folks like me have learned to just carry in their heads as they go. Its almost impossible to remember how little I managed with 2D CAD (MacDraw actually) first time round 30 years back and how hard that was.

But paying £1,000 for another upgrade of VectorWorks when Apple system upgrades break what i have isn't attractive and I do want to get this CNC thingy going so I'll have to find a way. Once I find the right mouse hole to wiggle in through hardest part will probably be the what "I'm used to" mindset (I can do this much faster in VectorWorks). As ever a month or three past the Eureka moment I shall wonder what the fuss was about.

Clive.

.

[Russell EberhardtParticipant @russelleberhardt48058]

For me, it depends on what I'm doing as to what drawing system I use.

For initial ideas I usually make freehand pencil sketches on the back of old computer printout sheets.

For making individual metal parts, perhaps to replace a broken part of a machine, I use 2D CAD (Draftsight) which I finnd quick and easy to use having used Autocad on and off since release 1.4 in the early 1980s.

For a part to be 3D printed or a simple assembly of parts I turn to Onshape, chiefly because it will work under Linux. It does full parametric modelling, however gets a bit slow for large files.

I've been trying to get to grips with Fusion 360 but as I have to reboot the computer into Windows 10 and then wait for an eternity for it to configure all its updates and reboot before I can do anything I don't often bother.

Russell

[Ian HewsonParticipant @ianhewson99641]

I agree with Larry, never had much use for drawing boards and certainly do not want to have to learn cad at 73, much too busy making things using my head for the design process.

I may be old fashioned, but the worl seem to have gone totally electronic without many hands on skills being valued.

A recent servay found that the only jobs likely to survive the oncoming robotics would be the skilled Hans on fettling ones, that repaired and things, as not all things are throw away yet.

Wouldnt be without my iMac, iPhone and iPad though.

[Neil WyattModerator @neilwyatt]

The trouble with 2D cad is it ruins you for 3D cad.

If you try and make 3D objects in the same way as you do on paper – thinking it all our in one plane then projecting it into 3D you won't get far.

3D design is best approached like machining, creating primitive, simple shapes that you fuse, intersect and subtract from each other to get more complex shapes.

[blowlampParticipant @blowlamp]

This is a reasonable starter video, which demonstrates some simple techniques to create 3D shapes from 2D shapes within MoI.

The simple interface belies the in-built power of each tool or function.

Martin.

[MuzzerParticipant @muzzer]

And when you are creating 2D drawings from 3D models and assemblies, generally you are extracting and presenting the info you need to machine the parts. Simply ensuring that every feature is fully defined isn't enough. You need to think about the machining processes and sequence so that the various dimensions shown are what you need when standing at the machine. Otherwise you end up going back to the computer to redimension the relevant feature part way through the job. Eventually you get the drawing creation more or less right the first time.

Some of the 2D drawing stuff goes away with CNC but you still need to think about how you will hold and machine the part, ideally before you even start modelling it in any detail. It's still perfectly possible to design stuff that is almost impossible to produce or simply more complex and fussy than it need be.

Murray

[duncan webster 1Participant @duncanwebster1]

I would not go back from 2D CAD to a drawing board for all the tea in China. I'm trying to get #2 son to teach me 3D but he is about as patient with me as I was with him when trying to teach him maths when he was at school. Not very, we both work on the 'I can do it so it must be easy' principle. I'll get there. The beauty of CAD isn't just drawing stuff, it's when you want to make it say 5mm longer. With a pencil you have to rub it out and draw it again, with CAD you just click the stretch icon tell it how far and which direction and bingo, 2 seconds and it's done. If you want to know where the centre of a fillet radius is just ask, with paper and pencil it was a bit of trigonometry. Want one opposite hand, just click mirror, and so on ad infinitum.

Edited By duncan webster on 20/03/2018 15:40:52

[Involute CurveParticipant @involutecurve]

I used to use a drawing board, I actually started at home aged about 7 my grandad taught me, he worked for BEA as an engineer, we used to build model aircraft control line initially and later radio control.

I got into Autocad very early about 1987 on 8086 with Co pro, but had been using CATIA on a Sun system prior to this, I later bought Autocad 10 for home use in about 1989, I still have all the books and discs in the original box, it cost a fortune at the time.

Over the years I've probably used most cad systems, I've seen loads of draftsmen struggle, especially early on, modern 3D modelling systems are a world away from the old stuff and are now true design tools, but only if you know how to use one without thinking about it, by that I mean its native to you, in that you instinctively know what to do to create the feature you want, if you have to look for a method, ie consult the help system, or search through the menu system for some feature, your still learning and are not yet proficient with the tool, it could also be you have the wrong software for the job in hand, organics are still the most difficult thing to design in cad, but its getting better all the time, I've used Faro arms clay modelling software, Sense 3D, but its expensive, we had a play with Zbrush at work looks really good we may will buy a seat if we think it will get some use.

Shaun

[Swarf MakerParticipant @swarfmaker85383]

Clive,

I think that there is a fundamental problem for many people that wish to get familiar with 3D CAD, and that is the lack of basic tutorials. If you are anything like me, who needs the manual!

However, this is one case where it pays dividends to get to grips with two things: One – the nomenclature – which may not be quite what you thought the words meant; and Two – the structure that the programmer expected you to put in place and follow during construction.

For F360 this is important, but contrary to the belief of some, it is entirely appropriate to start with a 2D sketch, the fag-packet equivalent. Indeed, in my case where I sometimes call upon 2D drawings made some time ago, I start by importing a dxf file.

It's not appropriate to try and do a tutorial session via the forum so I have sent you a private message.

Edited By Swarf Maker on 21/03/2018 00:17:05

[Neil WyattModerator @neilwyatt]

See the 'training films' link here:

paulthecad.com/product-category/cad-training/

More details here:

paulthecad.com/product/turbocad-training-films-usb-drives/

Neil

[Russell EberhardtParticipant @russelleberhardt48058]

For those looking for a printed manual for Fusion 360 the official one is here

It is written as a series of tutorials and has a useful list of keyboard shortcuts at the end. Be aware that; if you want to print it, it is about 200 pages.

Russell

[Paul LousickParticipant @paullousick59116]

3D CAD is a complex program to learn, much like learning a new language and the better CAD systems are difficult and time consuming for a new operator. Once learnt, would never go back to the manual method.

I have been a mechanical draftsmen (draftperson to be politically correct) for 35+ years. Starting work on a drawing board and then Autocad 2D. My introduction to 3D was Pro Engineer. Training for basic level operation took 1 week full time at a training centre. 3 or 4 weeks later I returned to the centre for another week of training for the advanced level modelling course. Then again later for an advanced drawing course. It was estimated that it would take 3 to 6 months for a compitent draftsman to be as efficient producing drawings than he had been doing them by hand. After this time it was far quicker to produce drawings than before. Especially if it was only to make midifications to and existing drawing. Modern CAD system are much more use friendly but still take a while to master.

Accurate dimensions on hand made drawings has to be calculated. Overall lengths of multiple parts had to be added together, sometimes with mistakes, To eliminate mistakes before production, the drawings were sent to a second person for checking. CAD drawings are extremely accurate and therefore often do not need to be checked for correct dimensions. The top line CAD systems can automaticall check for interference between parts. They can also calculate the mass and centre of gravity. Some also have finite element analysis modules to calculate stresses.

As projects get more complex there is a high risk of making mistakes. Parts which have to be modified or scrapped. The traction engine which I am building has many parts and everything is modelled on the computer before I commence machining and wasting time and money.

After the model is complete, assembly and individual part drawings can bequickly produced. Dimensions for parts can be automatically (or manually) added to the drawings. When any change to the model is made, all of the associated drawings are automatically updated. Even possible to change the model by changing dimensions on the drawings. Assembly drawings can be automatically populated with item numbers and a Bill of Materials.

I use Solidworks which has a sheetmetal module which can create layout drawings of bent plates in the flat state with position of the bend line for pressing.

Paul.

[MuzzerParticipant @muzzer]

Nice work Paul!

Note that Fusion has most of those features too – sheet metal, FEA (stress, vibration, buckling, thermal, thermal stress, design optimisation etc), animation, rendering, surface modelling and of course full multi axis CAM. It's aimed at the same "mid-range" professional users as Solidworks and must be about 80% there now I'd guess. And free for amateur use.

SW costs an arm and ten legs – and they really don't like it if you refuse the annual "support" (another half dozen arms and legs per year), yet it is so bug-ridden that you need the support in my professional experience. It's that arrogance that Fusion and Onshape are cashing in on although to be fair it is at least relatively easy to learn and use. I enjoyed it but couldn't see any way to justify it for my own use. And then there would be a similar cost for the SW CAM plug-ins….

The more work I did in SW, the more uneasy I felt about whether I would be able to afford to access it in the future. Now everything is in Fusion and of course I can import most of my previous SW (and SE) works.

Murray

[Paul LousickParticipant @paullousick59116]

I'm still running an old version of SW on a 32 bit computer which is pushed to the limit sometimes. Have been building the engine for 5 years now and did not want to change software. Even though you can export/import to a different CAD system, there are always some things thet do not work properly. Like everyone else, I use what I know. Will have to try Fusion soon (still looking for a roundtuit). Although after you have masterred one system, it is normally easy to learn another. Most work in a similar way.

Paul.

Edited By Paul Lousick on 21/03/2018 12:32:25

[MuzzerParticipant @muzzer]

Yes, for one thing you lose all the mates / joints when you import, so assemblies need to be put back together. In Fusion, you can use "as built" joints, so you don't have to move the parts to re-mate them but the whole mate / joint concept is different in both Fusion and Onshape to the way SW does them and takes a bit of getting used to.

My access to SW was either through spare licenses at work or using my kids' academic (12 month) licenses. But once those went away I was on my own and all my work compromised. I certainly wouldn't change horses mid project if I were you and still had a working SW license.

Murray

[richardandtracyParticipant @richardandtracy]

We're running SW2014 and refuse to shell out for the regular bug fixes. As Murray says, they cost an arm and several legs. We just get to know what the bugs are and find work-arounds for them. There are quite a few memory leaks in the version we have, but it's not as bad as the first version we used in anger (SW2006). After half a day's use it's often necessary to re-start the PC to get everything functioning properly again. Not terribly good practice in the programming to make that necessary, but it shows they have better error handling than I can manage to prevent the errors killing the program.

For home use, I doubt I'd find it worth the cost, and would try to go for F360 or similar.

Regards,

Richard.

[MuzzerParticipant @muzzer]

It's ironic that their pricing policy actually rewards mediocre programming. By releasing crap code, users pretty much require the "support" to get new releases up and running, along with "updates" after each major release that patch up the crap code to make it almost workable. If they wrote and tested it properly in the first place, they wouldn't be able to force the "support" on you.

I really struggled with installation of the SW Student release a couple of years back. Obviously, the moment you told them you were talking about a Student license they would tell you there was no support (ie nothing in it for them). And having released it, if there were any issues it was just tough titty. Go sling your hook etc.

There's a lot of jargon used in software to make crap offerings sound almost professional. Our guys used to talk about various levels of "release candidates" before they got around to beta testing and finally more "release candidates" getting closer to the deadline, then follow up the actual release with bug fixes and updates. They would then evangelise about exciting new(?) concepts like scrum, "kanban" and "lean" as if they had some insight into development excellence, or had actually invented the words. With hardware, once it's shipped, re-releases become somewhat more tricky, as you don't have the luxury of endlessly throwing it at the wall until it sticks.

Murray

[Clive FosterParticipant @clivefoster55965]

I know exactly where Murray is coming from with regard to drawings trapped on an unaffordable program or an old, obsolete one. I have a 13 year stash in VectorWorks Mechanical (as was) and the prospect of £1,000 for an update when Apple OS updates break the program is less than appealing. Especially as the mechanical side has been abandoned and hasn't been updated in ages. Fortunately its a pretty complete package for 2D. Never tried the 3D side. Probably great at 2 1/2 D for simple CNC. I use Superduper clones as my back-up system so, if worst comes to worst, I can always clone off a working OS – program pair and use that. On another machine if need be. Scary when replicating hardware is cheaper than updating. There is a 20 year pile in MacDraw too which was my CAD program for far too long. Less than ideal but I knew how to drive it. Less said about the TurboCAD Mac / TurboCAD Mac Pro ones the better. Just started to get my head round it when IMSI canned it.

I suspect that a major issue for folk like us when approaching Fusion 360 is that we are used to learning just enough to get todays job done. Every time we hit something new we make like riki-tikki-tava and run and find out how. Which steadily builds into a good stack of knowledge for doing what we do but leaves huge gaps covering things we haven't yet done. Fusion 360 isn't really geared to that sort of approach.

The official tutorial based handbook in Russells link is quite good. Came out a bit wishy washy on my Brother printer tho'. I always put such pages in clear loose leaf pockets rather than simply punching them. Boxed packs of 100 or 200 can be found for £ very reasonable mail order. Maybe less than 1/5 th of price for shop bought brands, e.g. Rexel et al. Means you don't tear out the holes in the aper and, if its a car manual or similar, proof against greasy fingers. But its no substitute for proper, indexed manual when you want to know how to use that command you can't get to work as it ought or even find the function that you are certain is in there somewhere. VectorWorks help is moderately good but I still sometimes find myself faking through the manual until a possibly relevant picture pops up giving clue to roughly where things are. Can't do that in a help file search. Often serendipitously productive when I find something I didn't know VectorWorks could do. Usually about 5 years after it would first have been handy.

Clive

[richardandtracyParticipant @richardandtracy]

Posted by Muzzer on 21/03/2018 16:22:56:

It's ironic that their pricing policy actually rewards mediocre programming. …

Murray

Got a classic case of that with the payroll/purchasing/MRP software where I work. It's 'Epicore'. The software is provided 'free', they make their money in consulting & programming fees to 'customise' it for you. It's a license to print money. They provide a default template invoice where the user can put in their own address etc. The default template does not include VAT. So Epicore are called in to add a VAT field, and lo & behold it costs around £1k to add at their £200-ish/hr rate. Multiply that by every customer who needs to charge VAT (ie every customer big enough to need an MRP system) and suddenly the rewards for bad programming are astonishingly lucrative. It's years past the point when it would have been cheaper for me to programme the MRP system from scratch. (And further more the data files would have been in ASCII so if there's a muddle, it could have been rescued manually rather than the binary used for the current system).

With the old 'NISA' FEA system there was a £1600 'support' fee which included an update every year. I noticed that bug fixes introduced in year 2 to correct problems in year 1 software were removed in year 3 and put back in year 4. What finally did it for us was the Y2k kerfuffle. They had hard coded the year as 19xx in the output files & never bothered to fix it even despite the 'End of the World, all computers will die' Y2K moral panic that happened in 1999. At this point we went back to the last stable version we had and invited NISA to get lost. I ended up writing my own 3D modeller that enabled models to be created quicker than with the modeller supplied with NISA at the time ( **LINK**&nbsp and for a while it kept our usage of NISA competitive for FEA consulting work.

Regards,

Richard.

[MuzzerParticipant @muzzer]

Richard – wow that was quite a job! Looks pretty capable but clearly must have taken some significant effort. For reference, it seems that Autodesk use Nastran in their FEA offering. Seems to work very nicely on the occasions I've used it.

There's also a bit of a parallel (in my eyes) with the general consumer quality culture and legislation in the States. There they still have that "12 month warranty" concept (remember when we did that?), after which you can go whistle. And worse than that, the moment you walk out of the shop with a purchase, the retailer has no further obligation to you in terms of issues with the product. It is now down to you to contact the manufacturer and fight it out with them. Of course this generally means dealing with a company half way across the continent and requiring their agreement (by deigning to issue an "RMA" number to you) before you can send stuff back to them – obviously a lot of people give up at that stage. I can't help thinking this is one reason there is so much crap on sale over there and many of the local products are so unreliable. Product names tend to include things like "dura", "pro", "reli-" etc and they may offer a more expensive "pro" version that claims better life. They also don't have the same ideas when it comes to advertising standards. So you find that the vast majority of black tea on sale there claims to be "orange pekoe" (ie the very best quality – when clearly it is actually sweepings and tailings) and you can buy "100% real Parmesan cheese" that is made in the US (go figure). God help us all if the idiot Fox manages to open the door to shiploads of their crap assailing our markets….

Murray

[Peter Edwards 6Participant @peteredwards6]

I use Solidworks and have for a long time. For simple items it would be quite easy for a beginner to learn. For more difficult pieces and assembly, and for complex shapes it is a different story. There is no way I would go back to a drawing board, and the ability to rotate/slice/colour/change etc your model and produce traditional orthographic 2D instantly with a CAD package and produce STL files for 3D printing, etc makes CAD essential. I don't think the drawing board is used at all now in industry (or what's left of it!).

[MuzzerParticipant @muzzer]

Companies used to employ vast warehouses (DOs) full of draughtsmen. Nowadays the same work can be done by a small handful of CAD jockeys. Many of today's mechies seem to have very little experience beyond the office but there again, I recall quite a few of the draughtsmen had a chip on the shoulder so were a PITA to deal with. Being a graduate, hands-on and handy with technical drawing didn't always go down too well. Mind you, when I started working in the mid eighties, we were still sending silly paper memos to people in the next room and computers were seen as a silly distraction apart from use for PCB layout. Thank god things have moved on.

Murray

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