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1982shawn

Plastic
Joined
Jan 5, 2008
Location
washington dc
I have only used cad a few times. I downloaded a free program and toyed around with it for a couple of months.

A project that i am working on needs certain pieces laser cut. My local laser cutter said to just email them the dxf file and they can cut the pieces. The problem, the blueprints i have are on paper. Id really like to find a cheap cad program and draw the pieces over again so i can make some changes and improvements to some of the parts. Most of the parts are on flat plate and what i consider pretty simple(and hopefully wont take long to learn to draw)

What cheap cad programs do you guys recommend that use the dxf file format?

I saw turbo cad version 10 on ebay for like 20 dollars. It says it saves in 25 different formats but doesnt specify which ones.

Thanks Everyone for the help!
Shawn
 
Well, since you've said laser cut, I assume 2D is best.
You've also said existing paper print to be copied and then perhaps modified, I'd have to say geometric is a far better choice than parametric.
Lastly, price to be low.


How'bout A9CAD?
A very decent knockoff of Autocad's interface and is quite capable. Native format is DWG, and it will fully convert to DXF.
Price, last time I've checked is free.

http://www.a9tech.com/
 
In a really really general term?

In geometric, everything you draw as it is intended to be. A 2" horizontal line is drawn as a 2: horizontal line. A 2" circle at the end of this line is drawn as a 2" circle with the center points at the end of this line. Period.

In parametric, you throw a line and a circle on the screen anywhere, and then tell the program that the line is 2" long and horizontal, while the circle is 2" in diameter and it's center is at the right end of the line.

Benefits of the parametric is obvious for the designer or engineer. As long as you've established your constraints correctly, any change you make will reflect in the entire drawing. In the case above moving the line will also move the circle, as it is defined that the center of the circle is at the end of the line.

The same thing for geometric would require you to select the line and the arc, and move them together. If you move either one, the other remains put.

Ok, sounds great, parametric is king, right? Well... not necessarily.
You see, depending on the constraints, while moving the line will move the circle, the opposite may not be possible. IOW, you may not move the circle at all unless you break the relationship between it and the line. That now require a 3 step process. Break the existing one, establish a new one, and then verify that what you just did does not violate any other constraints you may have. Imagine if there was another line, who's definition depended on the circle. Quite possible that moving the circle will make the line impossible to create.

In geometric none of these restrictions exist. You're free to do whatever you want whenever you want, albeit at the risk of creating invalid geometry without the obvious signs.
Not to worry though, the ability to use so called snaps help to completely eliminate that risk.


Anyway, since you're copying a drawing, it may or may not be properly dimensioned as to determine the design intent. If you cannot do that right off the bat, you'll have a much harder time using a parametric program. Also, in order to follow a properly dimensioned drawing, you must be drawing in the exact order the design intent is suggesting, otherwise you'll have a wicked mess on your hands. This may go head against the obvious drawing flow, and proove to be quite time consuming.

Lastly, this is a sheetmetal to be laser cut. My guess is that it would also need to be nested.
More often than not a nest is the most efficient with parts rotated, flipped, mirrored without any geometric regard to the other nest items. As long as they fit with the laser's kerf, you're fine.
This is a virtual nightmare with parametric, as each item NEED TO BE constrained in space with respect to the other items. As you put more and more items in the nest, the more difficult it gets to define them.
OTOH if this is a straight array of each item, then parametric is the boss, as you only need to change the X and Y increments of rows and columns, change the # of rows and columns and Bang! You just re-nested from a 12" x 12" to a 4' x 8' sheet.

Anyway, check out some of the freebie stuff first.
 
I'm semi-satisfied with DeltaCAD, and it exports in dxf format, I guess. It's very easy to use, as far as it goes, though missing some features I wish it had.
 
Solid Edge 2D drafting is free, and parametric. It's the 2D only part of Solid Edge V20. It is vastly superior to the 2D portion of the cheap 3D solid modeling softwares.
 
just do Fusion 360 its free to enthusiast or $500 a year for everything.

or Onshape free for a limited number of files.

both are cloud based, but Fusion has a work offline mode too.

or ask the laser guy how much for him to do it, he has to have some sort of CAD.
 
To the OP. A lot of your choice will depend upon your priority, right now I'd guess it's getting this project to the machine. If that's true then select the program that's easiest to learn so you accomplish the task at hand, likely a 2D program will be fine. Files can be saved to types most commonly used so that shouldn't be a big concern but do ask the operator which file types the machine uses just to be sure. Some lasers and water jet machines use a propriety file type (or so I was told by the operator) and need to be converted at the machine itself but that shouldn't be a concern either if it does because the machine should be able to convert the common types to what is required.

What you should aslo be asking yourself is what you intend to be doing with a CAD program in the future. Some are just fine using 2D programs for sending plate work out for machining. Nothing wrong with that either. The 3D programs have much more potential (and can still produce 2D files/drawings) but the learning curve requires more time for proficiency. If you need/want to design parts, work with assemblies of parts, or explore the possibilities of creating things that aren't flat then perhaps 3D CAD software should be considered. Most of the 3D programs even come loaded with tutorials that help get you up to speed in fairly short order. I won't advocate one over another, there are many flavors to choose from that all have inherent advantages/disadvantages but there are enough out there to pick one that suits your targeted capability/budget. Use 2D to get the task at hand finished but try learning 3D if you think it would benefit your future. JMO. :codger:
 
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A newbie cannot choose what CAD system is easiest to learn, be it 2d or 3d.

Imo, as an expert, rhino 3d is far better and faster and easier to learn and use than anything else.

30 years experience, from adesk 3dstudio to proengineer to acad to cadkey to catia to solidworks.
And coreldraw and photoshop to pro prepress and press levels.

The main problem is too little tutorials on "howto" make a simple shape.

All the sw will need a good bit of tutorials and exercises to get good at it.
Not hard, but laborious and takes time.
 
Imo, as an expert, ....
30 years experience, from adesk 3dstudio to proengineer to acad to cadkey to catia to solidworks.
And coreldraw and photoshop to pro prepress and press levels.
...
Not hard, but laborious and takes time.

Holy Crap Hanermo!
Is there ANYTHING you haven't done in your lifetime and not an expert on?

I mean you have done it all! CAD, CAM, machinetool distributor, car manufacturing.
Expert in the investment sector, specializing in the transportation and energy markets.
Traveled the world 5 times over, lived everywhere. For years !
Curious, was it you that took the pictures of the moonlanding also?
 
I have only used cad a few times. I downloaded a free program and toyed around with it for a couple of months.

A project that i am working on needs certain pieces laser cut. My local laser cutter said to just email them the dxf file and they can cut the pieces. The problem, the blueprints i have are on paper. Id really like to find a cheap cad program and draw the pieces over again so i can make some changes and improvements to some of the parts. Most of the parts are on flat plate and what i consider pretty simple(and hopefully wont take long to learn to draw)

What cheap cad programs do you guys recommend that use the dxf file format?

I saw turbo cad version 10 on ebay for like 20 dollars. It says it saves in 25 different formats but doesnt specify which ones.

Thanks Everyone for the help!
Shawn

Hi Shawn,
if you only wants to make flat plate cuts, just scan your paper-blueprints, save them as PDF, JPEG, BMP or some other Graphic-extension,
if you are finished and have them all together you can send them by mail and i will convert them to DXF or STEP/IGES file,
depends on witch 3D-Cad modelling program you are going to install, and use to do some changes or updates/corrections to your
then digitalised blueprints.

YouTube

Take a look at the you-tube-link, its all not that difficult,
and for the CAD modelling program i would advice to free download and use FREECAD in combination with INKSCAPE,
all free and super to use for what you want,
cheers, Jack.
 








 
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