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  • BillH
    Guest replied
    This is for hobby, for my own pleasure. To me, the whole point of using CAD is so I don't need to use a pencil and paper.

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  • oldtiffie
    replied
    Where's my caddie?

    There are a lot of "problems" that some have with geometry and trigonometry as well as "shop math" that can be solved very quickly and intuitively with the simplest of CAD systems.

    Solving for settings, angles or sizes are pretty quick and easy as well as giving you a very quick visual picture of everything without any (or not too much) formal "math".

    Angles for off-sets for taper turning is a prime example. So is sketching for a "3-wire" thread measuring set-up where the formulae and variables in the tables that come with the "3-wire"set can be a real PITA and "slips" too easily made. Just sketch it in CAD and extract the sizes/dimensions you want from the sketch.

    Very quick assembly sketches can be made to ether see that - or how - part do (or don't) fit together - or what options you have to make of fit something in an assembly.

    This is the electronic basic "back of an envelope" stuff.

    All too often all that is needed is a "2-D" sketch/concept without dimensions at all as they can be "picked off" as and if required.

    Many associate it with being an electronic "drawing board" (which in many cases it is - but not always) which suggests a fully formal drawing. I use it as I would a bit of paper in the shop.

    But I can sketch faster and better by hand in most cases.

    That is all going to change when I have to "get my finger out" when I start delving into CNC!!!

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  • Stepside
    replied
    I would have to say this has been a discussion where I agree with most everyone. It boils down to what you want to get done, how you approach a problem, how much you want to learn as well as available funds and output devices with their needs/requirements.

    I just finished a lighting device for our kitchen--sketch on the back of an envelope and a rendered Rhino drawing for the wife. built it from the sketch.

    Needed some cams for a mechanical timing device--draw in Rhino as a 2-D drawing and sent to the laser engraver for acrylic parts.

    Building a Side Lever Steam Engine from HSM ---draw 3-D metric in CAD insert it in a "inch" drawing and scale 1-1/2 to 1. Then adjust fasteners to fit the enlarged model and machine with RhinoCam.

    Building some machine parts for an important customer -- redrew his drawing with CAD to find his error and then machined part on a manual Bridgeport.

    Drew a 3-D drawing of a foundry pattern-- had it printed with a 3-D powder printer and sealed it with epoxy resin and painted. Rammed up the pattern in green sand and cast in aluminum.

    My point being -- Use what you have to solve your problem with the ammount of effort you wish to expend. There are a multitude of different software programs available but they are just tools just like the lathes, milling machines, welding sets ect.

    So play safe and play often.

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  • toastydeath
    replied
    Originally posted by loose nut
    Toasty, the whole point of these newer 3D cad programs is for designing equipment from start to finish, thats what they excel at. You might sketch out an idea on a napkin but the whole design is done in the cad program. The Boeing 777 was designed on one from start to finish, no paper and pencils or other methods and sent to production without any mock ups or other preproduction work, it's to expensive to do that anymore.
    I am just conveying my experience in a production environment with SW, regardless of the what advertised point of the program is.

    My own experience and other people I've spoken with in other companies, solid modeling is not the space to be working out the top level design of something in most applications. It's possible, but it's cost prohibitive for many businesses from a time standpoint. I have heard of more people at home doing this than I have businesses, because hobbyist time is relatively cheap compared to an hour of time for an engineer.

    Feel free to disagree with your own experiences, but that's my position on the current state of solid modeling no matter what they claim on the box.

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  • loose nut
    replied
    As an alternative to SW you can get Inventor Lite for free, it's similar to SW, they are both parametric modelers and are each other chief competitors, but it has somethings disabled to make it "free", no assemblies and some of the bells and whistle are missing.

    Toasty, the whole point of these newer 3D cad programs is for designing equipment from start to finish, thats what they excel at. You might sketch out an idea on a napkin but the whole design is done in the cad program. The Boeing 777 was designed on one from start to finish, no paper and pencils or other methods and sent to production without any mock ups or other preproduction work, it's to expensive to do that anymore.

    Leave a comment:


  • toastydeath
    replied
    I use solidworks at work, school, and home. Have used Pro/E, have used mastercam both in brief spurts.

    I don't really think of any 3d program as a primary design tool, and I don't think many people try to use them as such. They're second-step design tools at best.

    If I don't know how long I want something major, it's time to get a sheet of paper out and do a hand sketch, or to draw on a bit of bar stock. I draw out what I want, and put the major dimensions on it, or notes on how big I think it should be. After I have a general idea of what it is that I'm making, then and only then do I fire up a solid modeling program. With the major critical dimensions mostly in place, it's then trivial to come up with the other dimensions. But there's got to be a place to start, and that's a hand sketch.

    But also, similar to what TGTool does, I sometimes use solidworks to figure out dimensions for something incomplete very quickly. That's usually as far as it goes, though.

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  • rdesign
    replied
    I use Solidworks (2008, premium, toolbox, a nice seat) almost every day, it is great sure, but out of the hobby realm for sure.

    I own Rhino/RhinoCAM Basic, and I agree it will grow on you. I don't know if it was absolutely the best package for the money but I have figured ways to work around every limitation so far. I am happy with the purchase. You can build accurate solid models it is just a different approach. Learning how to do something new is good for your brain too!

    Is this a business or hobby or is the line to blurry to tell?

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  • kf2qd
    replied
    Problem isn't with the program...

    The problems you expressed with some of the CAD program isn't that the program is so bad, its just that some of the ways to do things aren't very intuitive. I have used Autocad for few years and I use it to whip out a quick & dirty sketch or to go for details in a model design. I can visualize a 3D object ans tehn slap down multiple views with all the internal parts on different layers and in different colors and make modifications and find it a joy to use.

    Now those various 3D programs are a royal pain - BUT then i have not had much chance to use one and get familiar with it so they MUST BE a royal pain-in-the-drain to use.

    If I could get my hands on one cheap enough I might try it, but I still have to get my parts to a 2D surface (paper) in order to make it. And I have seen some pretty poor attempts to use a 3D program to produce those 2D prints. It all boils down to how proficient the designer is with the tools he has. You may like your 3D cad, but I can't afford it and I can get things done nicely with my 2D programs. Pick your favorite poison, but be careful about what you say about the other guys program just because yuo have not had time to become proficient.

    By teh way - In autocad you start out with a few lines, make some parallel lines, some lines at right angles and such just like teh construction lines youi used on paper. Then you delete some, trim some and a drawing appears - kind of like the light pencil drawing that you later inked. (I am old enoughto have done pencil drafting, but no inking...) Don't blast somebody elses tool just because you don't have the skills to use it, be kind of like condemning CNC just because its not manual.

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  • Spin Doctor
    replied
    Cut my teeth on AutoCAD and I confess I like it. But then I am used to it. Rhino's interface is/was very similiar from what I remeber of playing around with it. SolidWorks, I just never had enough time to play with it and now I don't know if I ever will take the plunge. By the time I get to doing it in CAD I've already worked most of it out on paper

    Leave a comment:


  • BillH
    Guest replied
    Originally posted by Stepside
    If the RAM question is in regard to Rhino then the answer is 2 GIG is adequate for most things. If doing some intricate design work then 4 GIG might be better.
    If you even want to take advantage of 4gb of ram, you'll need a 64bit OS.

    Leave a comment:


  • Stepside
    replied
    If the RAM question is in regard to Rhino then the answer is 2 GIG is adequate for most things. If doing some intricate design work then 4 GIG might be better.

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  • TGTool
    replied
    I've used Turbocad through several versions now. When I first got it, version 9 I think, I just got terminally frustrated trying to use it. I couldn't find all the ropes and handles I wanted to make it do things. That may have been my myopia, because I'd worked on mainframe CAD programs years ago and this didn't have the same command structure.

    Finally I got out their 2D and 3D tutorials and went through them. Seeing the way they built things was the leg up I needed. Once I could kind of see where things were going I could poke around for the additional construction tools.

    Also, I initially treated it like a drawing board, stretching extension lines over to another view just like I would with a drafting machine. After I was reasonably comfortable with that though, I started actually making 3D solids so I could generate any kind of view, projection, section or whatever to get to the dimensioned drawing for the shop.

    Still often I'll often just throw a few lines and circles down to get a feel for proportions, clearances and things if I'm making something ad hoc without a complete design and dimensioned drawings.

    Interestingly, a few years ago I was in a shop for a couple weeks that built custom machines for manufacturing. Some of it was pretty complex indexing table assembly machines and so forth. The owner was a degreed engineer and did all the design, but he never did generate a complete machine drawing set. He'd have an idea to start with, lay out a few weldments, look at places for slides and ballscrews, then print out essentially just a one page sketch of stuff with essential dimensions and take it around to the machinists. By the time they'd have that done, welded, and heat treated (stress relieved) he'd have more sketches of what to machine next. Damndest system you ever saw, but lovely, lovely machines.

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  • noah katz
    replied
    "I have 8gig of ram "

    Do you need anywhere near that much?

    I use high end IDEAS solid modeler s/w at work and we only have 2 GB.

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  • BillH
    Guest replied
    Originally posted by oldtiffie

    A broader discussion will assist.
    Well what do I use cad for...

    I use cad for design and layout, from start to finish. I use cad for taking drawings of a live steam locomotive that may have been drawn in metric, I convert it over to imperial inch and redesign it to use standard imperial stock sizes. So I must assemble it in 3d, make sure everything fits, and even simulate the valve motion if I had to redesign any linkages. I have a kozo A3 engine that I drew in Solid works 2006 as a tutorial in learning the software. The results are simply amazing.
    Some times I do simple things like quick design theory. I may need to figure out an angle inside of a triangle and I am too lazy to use trig and a calc, so I use cad to tell me what the angle is. Other times I use cad to design a part for paper printout before I machine it.
    CNC work is in the future, perhaps far future, still need to pay off a 50,000$ loan for flight training...

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  • oldtiffie
    replied
    Wider

    There are many variations in CAD as regards price (initial and on-going) as well as versatility and value for money.

    So far the discussion is more toward the "top end" than not.

    Many may only require a simple sketching package, some may require a "try before you buy" package, others may only require 2D, others 3D, others a modeling package, and others may just require something that they can export DXF files from for use in processing for CNC code.

    The "all-in" cost of CAD is not just the software as there may be considerable other investments in hard-ware and time as well.

    Consequently, people's perception of "value" may not necessarily be just the features in a CAD package.

    Just to "stretch" things a bit, a "High end" package will not make you an expert nor will it necessarily solve all of your problems or meet all of your objectives. Neither, on the other hand will a "low end" CAD package necessarily not meet any or all of those objectives.

    A broader discussion will assist.

    Leave a comment:

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