SGI: Computer Graphics

APT is not foss but it's public domain, even better Not only that but it's proven ... SR-71, Apollo missions, XB-70, Boeing, Northrop, Douglas, North American Aviation, GE, Pratt & Whitney .... Totally parametric, three d, can handle shapes that the graphical apps can only dream of, nice program / language. No point and click though.

$900 seems pretty high to me for something you can't do anything with. I could see an 8" cube as being useful ....

Hello there, Hamei!



Well, I need to reckon I'm completely lost (seriously) and never heared about that! ...could you point me to some useful URL to start to grasp a bit the concept? (APT related, you know)

---

All in all, I knew from the start that FreeCAD is not into the same leagues that the biggest ones. My point was/is that it constitutes a more than interesting app if you use Linux (or any other POSIX with the required libraries) and believe me; you can do lots of things with it!

Just try it, and then let me know!

Of course if you are using a higher end IRIX box, we know there are better things into the the commerical lands, but this is FOSS, you know. At least for me, looks like the best FOSS tool around for the particular. Even on IRIX lands would be a more than nice addition! But my Octane needs some maintenance before to be able to try to port or run anything again.

Remember: I'm saying FOSS... don't bring to the table CATIA, PRO/ENGINEER, etc... because it could not compete (at least now) and there is no point comparing FreeCAD with something pushed ahead with dozens million dollars/euros of I+D behind.



Yes, that was my first point. But for some little lost-wax pouring models would be cool... amateurs, hobbyists, etc. There are many little useful things you can do even with such a reduced workable area/volume... but of course something around a cubic feet would be better!

The problem is, bigger workspace, bigger price!

Oh well, time to go outside to make some carpenter work for a loudspeakers order here!
All the best,
Diego

APT stands for Automatically Programmed Tools or any variety on that theme ... It's both a language and a program, came from MIT originally at the same time that CNC was developed / invented / designed, and by many of the same people. Then the aerospace industry took over development ... it was the very first ANSI standard and most of the aircraft built before 1980 would have been designed with APT. It was still common into the 90's ... the wikipedia page is not bad but if you're lazy ...

First step is to define the part using geometry statements. Common entities include circles, lines (in fact it's all 3d so a line is just a specialized form of a plane), cones, spheres, parabolas, hyperbolas, surfaces, mathematically-defined arcs, whatever. If you've played with FORTRAN the conventions will be familiar ...

CIRCLE1 / CIRCLE, POINTA, DIA 6
LINE2 /LINE, 12, 17, 44, TANTO, CIRCLE6

and so on ... gazillions of ways to define each entity.

The next section is tool movement commands - turn on spindle at 3000 rpm clockwise, turn on coolant, start from point A, rapid to point B, go forward to the intersection of plane one with circle three, turn left on circle three at four inches per minute to the intersection with plane five, rapid to the start point, turn off spindle, turn off coolant, rewind, fini.

Rewind refers to tape, of course. Did you know that SR-71 missions were controlled by a computer running paper (mylar) tape ? I think until the very end. Funny.

These days maybe that's too much work for people but compared to an HP-41, it's a dream. Also, as you can imagine, it's quite a bit more powerful than graphics programs if you are more of a programmer than a clicky-the-picture sort. For families of parts, just change the dimensions on your geometry. Run the part definition through the interpreter again. Viola, new part, same program. GE built entire families of turbine engines with a spreadsheet and APT loooong before MySQL was a gleam in Larry's gimpy eye.

The program is in the public domain - hard to find the source code though, it's so old and not sexy for the anti-aliased fonts crowd. Easiest way to try is to get a trial copy of Personal APT (web search) which is a subset of the complete language. Bob Drewry was involved in the original program, he's retired and messes with this in his dotage. He's created a Windows shell for today's users, I much prefer the DOS version. Price for the whole thing - program, manual, postprocessors - is around $300. Or was, last I checked. It's worth it. The manual alone is a full course in machine tool programming.

There were several other versions of APT out there but I believe most have fallen by the wayside. The military still uses it, I'd imagine. They've got all those B-52 parts to keep in inventory.


I've messed with every free cad app I can find, you can bet on that I don't like any of them very much. To tell the truth I am surprised there aren't any nice ones. There have been a few with promise but they seem to have fallen by the wayside. They are all so busy playing with their dicks that they forget the purpose of a CAD program - to draw/design stuff. 80% of the screen is icons. Hey ! Where's the damn part go ? Over here in this postage-stamp-sized mini-window ?


There is also Irit and that BRM CSG thing. Neither of those seemed very exciting from the point of view of machining tho.


Nah, I understand. But APT is going to kick ass over anything from Open Cascade for the next century. Much five-axis work is still done in APT. Just a few years ago it was all done in APT, because the graphics apps couldn't handle the math


Not to be mean but I can't see it being good for that, even. For small delicate work you want a very high-speed spindle and good rigidity and accuracy and repeatability. Little parts have details in the .0001"s. If the best your machine can repeat is .0005" (with luck) then you're going to be disappointed. That kind of accuracy isn't free. That little thing is so flimsy Ahnuld could crush it in one hand like a beer can. I can't see it being useful for anything at all.

Hamei: I can see clearly that your reply requires and deserves good attention, and I'm willing to read it more deeply than the hours of the midday allows me to do (if you happen to access some spy satellite around the sky, you'll be able to watch me cutting/sanding MDF and wood at my backyard right now!) so I'll read it carefully along next hours!

Thanks in advance and... I'll reply soon!
Diego

Very good, now my mind is ready!



Nice, now that I put to work those old rear sprockets, I seem to recall that in the school we studied a bit about APT around 1988/1989... along with DBase-II/III, FORTRAN, TurboPascal, and a few other things... that would explain why it sounded slightly familiar but I could not tell why...

But now I recall what was the use of APT there!, I think it was used in company of an orangey italian mini-lathe!

Anyway, sorry, you're right... I always use Google and Wiki for everything, but this time I given up too soon when I noticed a lot of non related results. So, double thanks. Yes, here is the APT Wiki



Yes, I know what you mean. I can see easily the beauty behind such no non-sense approach compared to any amateur class GUI, but I would be lying if I say that my actual rythm of life can support such thing for routinary work.

I mean, most part of the time I use CAD to develop a model into a virtual environment, before to build the real thing... but that's the key point: 99.99% of the time I'm not doing it to produce anything serial. My actual workflow depends on CAD mostly to produce blue-prints that then I use to build equipment by hand! So, strictly speaking, most part of the time I only use CAD but not CAM... even if here and there I use CAM too to control a couple of very specialized tools that I've built here.



Very nice, looks like the kind of techie's black-hole in which I use to fall here and there!
...but I can't help thinking how good would be to write some good wrapper to put everything under some GUI! Don't hate me!



Heheh!, nope, I was not awared of that! ...very funny, I guess the dummy mylar-tape sequencer was a lot less heavy than fully equiped PDP-6! A couple places here in the city used to synchro slide projectors by using dummy sequencers with tapes like that. I think our Municipal Planetary used something on these lines, but I think in this case was real paper (not mylar).



Yes, I know that geometry constraints are still a bit hard under FreeCAD, and you got a good point there... but it is not so difficult to find the way to do it right, even if the app itself still has some bugs...



Again, I think the problem is that I say "CAD" and you hear "CAM"!
...of course an integrated CAD/CAM environment is always better, but even if the CAM side of FreeCAD is still too young, the CAD side has little or nothing to do with the first versions... this thing evolved a lot, and for a lot of things you can use it with confidence... even if you end exporting the models to some machine trajectory optimizer.



Well, I'm looking at the site right now: http://www.cncfocus.com/
...I see what you mean. I can't say it is not interesting, and looks very powerful.

Anyway... what is wrong with brand-new apps natively oriented to G-Code / RS-274?
It seems pretty soon FreeCAD could be doing it well:

Organization Chart
Robot Workbench



Well, there are tons of CNC oriented stuff, and people wants to do whatever they do every day faster... I can see clearly that I'm not the only one hurried to get the work done, but I need to accept that I still hold it with some lyrism (i.e.: refusing to switch to MS Win even if many things are targetted to such so called OS)







No, no, no Hamei! ...look at it (FreeCAD) now !
What I'm saying is indeed that three years ago such app was a complete looser and now we (they) have something that is very-very cool and has lots of features that previously were only found into commerical apps! And believe me, has a lot of power under the cover... for first time you can do real CAD work with a FOSS app!

Just go there and download the actual thing! ...if you tried it when I posted this topic for first time, then you got the wrong picture of it...

Anyway, I understand your point: you're talking of mature industrial-grade CAD/CAM. There's no discussion about that. We'll have to wait some years before to see something F.O.S.S. including the whole real dealt.



Ditto!



Sure, I understand. There are lots of things that can't be done with OpenCASCADE on actual state, and even worst, there are still a few resilient bugs (some boolean operations, etc.)



Maybe for simpler shapes without too complex and/or too many curves it could work. I'm still more biased to think about some retrofit including some heavy milling machine, and so on... mainly because any real CNC, even if it is a many years old second-hand, is way expensive in my country. And I'm not even talking about BridgePort style machines. Anything with the "CNC" acronym costs many thousands here, even if it can't work without an investment of many thousands more!

Oh, well... time to eat something!
All the best,
Diego

If you are interested in early computer developments, I'll try to attach something historical. I found it interesting ....


There's a "project" called Heekscad / Heekscam ... kind of funny. Part of what they are attempting to do is re-create APT in python. Except it appears that they don't even know of APT's existence ? APT was written and tested to the max by every major aerospace company in the US, three guys in their mom's basement are going to do better ? It's free and public domain, but they feel they have to recreate the wheel ?

Sometimes you gotta wonder what people have between their ears. A lot of what they are trying to do looks nice but jeeze. Anyway ...


We have a lot of small sign shops making engraved plastic products with small cnc routers (with very basic z-axis control). They aren't very expensive. I've thought for a while that one of those would make a great base for a backyard cnc mill. They are MUCH more rigid than most of the scary shit I've seen on people's websites. Some of that stuff is awful. I'm sure they are having fun but jeeze ... everything you need to do a nice job is readily available but here they are, gluing popsicle sticks together to make a machine. Maybe I should make kits. Then all we'd need to do is make an O2 act as the controller. We could duplicate Jim Clark's disastrous ocean voyage

Of course, I really enjoy such kind of things.



I knew about that, but never caught my interest because when I looke at it it was still too green for any real use. I'm looking at their video right now and looks more interesting than last time I've visited their site...

I've read briefly the PDF about APT that you attached, and everything sounds extremely impresive considering it was around 1958. These giant milling machine at the page eleven made my day... since even for today's standards it is way awesome, and many factories would love to get one even if it has about 54 years as second-hand item!



Well, I could not criticize the hobbies from anyone else, since my own job is so wide in terms of variety of tasks that many times I don't know where is the end of my work and the begin my hobby... so... but, I guess you're right again!



Do you mean, things like the CNC-Sable or maybe bigger and more expensive things?

I know how to build a router, I've tried things along these lines for amateur CNC lands... but since some time now I was (I'm) more oriented to think that a retrofit-job for any good manual milling-machine would make the trick better than most part of the DIY routers that can be built in Argentina for under U$D2000.- (to say something)



I know what you mean, yes.

Anyway, the only time I was required to develop my own CAM software was the time I required to control a very diminute and specialized machine... and there was not any app readily available into the F.O.S.S. domain... for all the rest I use existant apps, including things like EMC2/LinuxCNC and FreeCAD.

Still, for the little app I mention, I discovered that was easier to write a brand-new app than having my brain burned by trying to customize EMC2/LinuxCNC for the required task and controller board... of course, I've developed the controller board along with the rest of the electronic an mechanical system too!

But I would want to add a main motif to develop and build DIY CNC things for some easy tasks: cheapness!




You should make kits, but there is no need to use an O2! You can use EMC2/LinuxCNC which works amazingly well for many things... if you happen to support the first months trying to configure the damn thing to work!

That's a beautiful little piece.

And I wouldn't pay ten dollars for it. For actual use, it's shit.

1) Made out of aluminum. Aluminum is one-third as stiff as cast iron. That means that for the exact same force, it will deflect three times as much as a part made of a more suitable material.

2) All bolted construction. Same problem. Bolted joints are nowhere near as rigid as weldments or castings.

3) The ways suck. It's very difficult to impossible to get the preload you want on round ways. If the female portion had seals and hydraulic oil pumped in under pressure they would be hydrodynamic ways, extremely stiff and very cool. But they aren't. If they are just a female bushing then you can't get the fit you need and can't ever adjust them for wear. If they use small balls for rolling elements then they concentrate all the loads on a very small area and wear very quickly plus have almost no damping effect.

4) The table : how the hell are you going to mount anything to that thing ? Every heard of t-slots, guys ?

5) The spindle : a three-jaw chuck ? Are those people nuts ? Any cutter except for a drill will have a sideways component of force. The very first thing they teach a person in shop class is to never I mean never put any kind of end mill or other cutter into a drill chuck. That means NEVER !

We could continue but will refrain

The point is, here's a very nice-looking device built with no consideration for its intended application. None whatsoever. I like hobbyists - I am a damn hobbyist ! but jeeze ... can we learn a little about the basics before we go making stuff ? Or writing web browsers ?


I don't see the price in this little guy but the sign machines are not nearly as pretty except they have the basics correct. I also have a hunch that the sign machines are a lot cheaper and they come with a working control right out of the box. It's in Chinese, of course, but still .... here's a (terrible) shot of a portion of a sign. Words are about 2 cm tall, workpiece was 14" by 22" (roughly 36 x 60 cm). Bigger letters in other areas, this just gives an idea of the accuracy of small cutters even with a small, cheap but properly designed machine.



If CNC-Sable is the competition, maybe I should go into the biz of hobby NC machines ..... their stuff is crap. Beautiful crap to look at but still crap.

If I was going to take up... milling... as a hobby, I'd get an old manual machine. You know, some old workhors that's worked quietly and just fine for the last 40 years in a shop somewhere.

Hell when I was 16 for a few months I was running a manual mill just fine, had a jig set up and a radio. sand down the sharp edges, have a box of parts ready to be welded together by dinnertime. "put the part in, turn this wheel until it stops, back it off, flip it over, turn this knob, etc, etc, make sure you keep the coolant going and don't break anything. The old man would be welding or assembling bits or something on the other side of the shop. You can always get an old machine (forget the CNC bits) and hire a teenager to run it. he can get you the coffees and smokes and sweep up too. I've seen beefy-looking used machines like that, 3 axis, you know, table moves x-y and the mill goes up and down, for well under a thousand bucks. I'd much rather start with something like that and add servos and a controller, than build the machine from scratch.

"when your only tool is a hammer... everything looks like a nail"

I still love working with glass / carbon fibre. especially for complex shapes. but not the fumes, oy!

That's almost exactly what I said above! But given my limited english, you said it better! ...you know, when I said:



...wanting to significate more or less what you said. As an example, even if you want to go for a brand-new machine (Taiwan), there are always things like this:



...but this is not the kind of machine I'm really thinking about. I'd rather would go for an old and greasy argentinean machine like this one:



...which is a real workhorse with which you can build (i.e.) a whole motorcycle engine if you need to. And there are already good samples of success retrofitting this kind of beasts to run with things like EMC2/LinuxCNC. Of course it will need some money to basic maintenance first, some space, and maybe a three-phase line but you can always use a phase converter.

The things that must be emphasized to read my above posts are:

1) In Argentina everything related to turnkey CNC solutions is valuated into the range of many thousand dollars.
2) In Argentine the major part of traditional heavy weight machine-tools manufacturers are not building anymore their own machine tools but rather re-selling some kind of lower-end asiatic version customized to fit a bit better the needs from their customers. But this benefit (lower price) is not translated to the customer or end user at all; because you'll end paying for the new low cost item almost the same price than for the old-fashioned but extremely reliable, built to last hundreed years, accurate and robust argentinean product!
3) In Argentina you can't import second-hand machine tools, because it is a violation to the customhouse rules. So, everything has to be brand-new , but the fees are insane.
4) In Argentina you can buy brand-new automation stuff, mostly limited to importations from asiatic nations or to manufacturings from local producers; but you can also find good spare components to build it yourself.
5) Still exists some rather limited access to the real thing , that if you can afford to it, and you can get either previous generation NOS or recent generation machines from traditional top quality manufacturers, or very recent higher-end and higher-quality asiatic machines... but this is mostly limited to medium-to-big size companies, because there are many "pluses" that you could not avoid into the form of insurance, extended warranties, maintenance contracts, obligatory support, spares, etc... the sum of this makes this stuff almost prohibitive for little companies (like mine). Modern machines are not built to last as much time as older stuff, you need to go at least with an insurance and extended warraties because you don't know when, but you already know that you'll need it sooner or later. Believe me, I know from two year old turnkey machines hurted to death because a spare needs to arrive from some other place and there is no local replacement even at the dealer's office!

But the bigger problem for us in Argentina is that, even if you can get from an eBay seller some top quality german or north-american milling machine for a few hundreed dollars, it will be completely irrelevant because will be nominatedly impossible to get the item here without paying *A REAL LOT* of money... and that if you are extremely lucky and your stuff does not get "stuck" into some customhouse wharehouse without hopes of freedom anymore.

Think of the actual version of my country into the lines of a '50's Russia mixed with a "Mad Max" film and some happy full-time tropical dance!

That's why second-hand, old-fashioned reliable machines are so interesting to my own taste. What do you think? Air-tickets for some other place? Anyone?

Hello there!



I knew it!!!, heheh!!!
Thanks to god you said it, because one of my customers is selling these shit stuff here in my country to jewellers for medal engraving! So, I'm free of charges! I've not launched the stone!



1) Sure! Anyway, better Aluminum and not MDF! Believe me, there are lots of commerical CNC routers here in Argentina being built over MDF frames!
2) Pretty sure too, yes... but you need to accept that in terms of assembly practicality the bolted construction is easier than weldments. To do it welded you need a good exoskeleton frame, already made with very tight tolerances, to help to hold the joins together in order to be sure that you'll not end with a useless structure once welded. Also, check out the very reduced workable area/volume. But I would go definitively for a casting structure, yes.
3) Do you really want to go all that far? Can be built some frame/structure with hydrodynamic ways for such a reduced workable volume? I mean... again, check out the travels! Look: "Travels: X-200mm * Y-150mm * Z-60mm" ...how would you manage to fit hydrodynamic ways into some desktop frame like this? Is it already possible at all with such a reduced target footprint? (It is not a retoric question, I'm honestly asking.)
4) Here I can not less than agree completely!
5) Ditto!, same as with the previous point (4), something like the Bosch GGS 27 L would be way better than that!

...and we should add...

6) The nuts and screws from the Sable machine are the same ones that you would use to assembly a very basic DIY machine, I mean, they seem to use common nuts and threaded rods from hardware-store! I mean, nothing with recirculating balls or at least some good Acme trapezoidal thread!



Sure!
Let's try with the next best thing for some extra dollars. What about something else from your country? Look:

Bodor CNC Router




Give them a slap on the wrist!



About U$D715.- at eBay U.S.A. for the whole thing, including everything, ready to hook up to your PC box... or if you prefer, you can buy the same thing in Argentina for U$D2599.- but that will buy you a parallel port cable and a cup of coffee too! Oh, well... ehrrr...



You're right, the picture is terrible! ...but I understand the idea!
So, any chance to see a picture from the kind of routers that you make reference? I'm genuinely interested, even if I know that the chances to get them here to my country are pretty narrow, specially if one refuses to sell a kidney to pay to the customhouses... but I'm still interested.



Never better said, and with your knowledge you should go... but I fear that with your (more polished and thorough) requirements, the overall cost would be from the very begin probably a lot higher than those U$D715.- from Sable... what do you think? Is it possible to put along something along the above mentioned lines for less than U$D999.- or something like that?

EDIT: Lots of typos...

Control, this is Qiqihaer 20. Can you give me a ground speed check, please ?


Have to go home, it's getting late here but General ... do you have any foundries available ? Can you run a table saw ? If not, a steel weldment is second-best ... you can make your own and beat the CNC-Sable price and quality.

Well, not that workhorse, but still!
Is it your factory, Hamei? It looks extremely nice!

Anyway... what has these giant thing to do with our conversation about quality/reliability for low footprint milling machines?

Now, talking seriously, what would be cool is some deskside-size milling machine with heavy duty capabilities... that's why I insist to look towards old milling machines instead of DIY routers... but since there is no real rush, I'm open to any good alternative/idea.

Around the '60's / '70's there was some generation of argentinean milling machines, fully manual and with 3D capabilities, enough dependable to be in almost every single workshop toolmaker and enough good to be still now operating with no more problems than an occasional change of ball bearings.

What is wrong with such approach?

The problem is, the little models are sold faster, and I don't want something like a Cincinnati No. 28-120 or anything like that!



Yes, I own both things and I can use them, what is your idea?



Yes, I own an arc welder and a spot welder (this one is manual) and I can use them, sure!

It's kind of two different requirements .... small parts need a high-speed spindle and fast, accurate table movements. Bridgeport work is more general-purpose, heavier cuts, not as accurate ... just different .....


Yes, this is one of the places that makes the routers that little sign shops use. They also make little laser engravers. They are not pretty like the CNC-Sable but the design is correct and the prices are reasonable. Too bad about your import problem ....


Nothing, except that it's kind of hard to put on top of your desk


If you can't beat City Hall, then play their game Make it in Argentina. There's nothing so special about those little machines that you can't build nice ones. And the competition sucks. So .... we don't all have to be "knowledge workers" toiling in the fields so that Google can know every single thing about our previously-private lives.

PM, general

Hello there!



Sure, I know, I thought that was clear. I mean, the problem is, I could apply for both requirements... which is first achieved is a matter of priorities.

Let's say: I frequently use plain parts with complex 2D shapes; that would be fine even for a 2.5D CNC router. Then I also need many kinds of fixation pieces with slightly more complexity into the 3D domain, different metals relatively more mass; that would be nice for a slightly more heavy duty CNC milling machine.

So, I think eventually I'll need both. That's because I'm sure a CNC router will begin to wear very fast as soon as I start to put the heavy stuff there, loosing exactness for more precision demmanding 2D work.

But you're right. I don't think a vertical column mill will do any good for PCB.



They had an importer a year ago, then the stock flown (seems it sold well) and never heared from them again. By those days I was almost ready to buy one from them, and then aborted the mission because they used a proprietary controller that required MS Windows to work... that was bummer, because I don't wanted to remove their nice controller to stuck inside a DIY thing just to be able to run EMC2/LinuxCNC, consumming more money, resources, time... loosing some nice status report features, etc...

But the frame seemed to me between the best things around the country; anyway it is not locally available anymore.



Touché!
Yes, the Barbero unit from above posts is a pretty big machine; but they used to build some kind of variation within the size of a minibar refrigerator, or a deskside Onyx if you prefer!



Well, you know (maybe better than anyone else here) that I was never good "Guitar Hero" player, and I always loved to compose my own music-sheet to play my own song!



Yes, I know there are very nice things that can be built into this field. I know. It is just I wanted to avoid me some time building my own tooling because because I was already there and I know the time it takes.



That sounds so clever, 老師i!

Is there even good 2D-CAD software for Linux nowdays? Last time I used Linux there was only Dia and not much else.

I mainly use RISC OS now, and use ProCad+ and Artworks 2 for drawing. Most things are much easier to draw in CAD software and then drop into vector drawing software for colouring and finishing.

I have no real need for 3D myself, as when in paper you only get 2D anyway.

Hello there!



Yes, there are actually many of them. But I was always more interested in 3D, and I'm very accustomed to it, so, I could not tell you if the 2D offer is bad or good for Linux. CADuntu/LibreCAD and QCAD both seems pretty good, but I'm not a user for any of them.

To be really honest, after I installed and tried FreeCAD, never touched anything else... Art O fIllusion feels like a joke compared to it, and BlenderCAD feels like the kind of a frankensoftware very cool for games or movies but with nothing to offer (at least by now) into an industrial CAD/CAM sense. Love it or hate it, but FreeCAD is the only thing capable enough to compete with a commerical CAD/CAM solution... and every day it gets better and better.

Just add the "Devel" repo to some linux box, and try every night some bleading edge features. Seriously, to my humble oppinion, it is the only F.O.S.S. thing capable for 2D/3D parametric design with a modern GUI today.



Sure, and I already praised many times the excellent quality for the RISC OS apps! I'm mostly sure the RISC OS apps designers are working with strongly task-oriented paradigms, pretty much like lots of IRIX apps that many people here knows very well.

The thing is, I don't own a RISC OS box, and sometimes you need something more portable. If you need to go extreme, there are things for iPad around ( eDrawings For iPad ) and I'm sure you could not go too wrong with it if you need a good viewer. But I don't think you can create anything using it.

So, I'm actually trying to train up my mind into the use of FreeCAD because it seems the kind of app that would be pretty soon avalilable into the repos of all kind of Android and/or Ubuntu tablets pretty soon. And anyway it never demanded from me any extra learning over the general knowledge that one commonly has for the use of all the previous CAD/CAM apps. And it's free!

I may have to check that FreeCAD when I get some Linux box running at some point.


I have never done proper 3D-CAD work, but used to do some 3D-modelling when I was younger. (Well, loaded Solidworks 1 times at school when was studying, but compared to some 3D-modellers the actual modelling tools felt poor.) I had sports injury some years ago and after that more precision work with mouse produced stress on the arm very quickly, so gave up on the 3D-modelling. Most 2D programs have very good drawing aids like snaps and configurable grids, so precision is achieved with very little extra work with mouse.

Drawing isometric pictures with 2D is not that different to working with 3D really. If you know the angle then its is just the matter of drawing some helper lines for the depth and then removing the hidden lines manually. If intention is to give object some colour and shading to make it look like solid, then it goes little differently.

Seems that 3D is the word of the day though, and even traditional 2D work, where linetype and width give most the information needed are switching to 3D and you can rotate the 2D view to get a view in 3D.

Mouse ? All the programs I have used take dimensions entered from the keyboard. I would hate to be limited to snapping or grids.

You might try to find a copy of Cadkey for DOS. Version 7 is the nicest, version 6 is decent. Maybe on fleabay or something ? It sounds like the way you work would fit that program well. It should run in a virtual machine ?


Yes and no ... a 3d model will (obviously) be 3d. To get any other view all you have to do is rotate the model. In 2d you have to make a new drawing for every view. 3d is a little more work upfront but at the end of the day it's a big timesaver.

Th real difference is between wireframe and solid modelling.


It has been for thirty years that I know of Autocad 2.52 was 3d ... the big switch was when everyone went to solids. Are there any wireframe cad programs still sold ?

Dimensions can be entered from keyboard, but for example if I wanted to copy some line or other object and align it perfectly with something. In ProCAD+ I could just use F4 to set snap point for the object, and then with correct snap settings could just drag it with right mouse button to get it copied and snap points correctly aligned.



I studied building services and the things I had to draw were things like pipes, drains, ducts, etc. Pretty simple stuff and remember using software like CADS where everything was 2D only with possibility to generate simple isometric view with correct settings. Later there were some programs that looked like you were drawing in 2D, but could rotate the viewpoint to get 3D-view.